USB2512-AEZG [MICROCHIP]

UNIVERSAL SERIAL BUS CONTROLLER, QCC36;
USB2512-AEZG
型号: USB2512-AEZG
厂家: MICROCHIP    MICROCHIP
描述:

UNIVERSAL SERIAL BUS CONTROLLER, QCC36

外围集成电路
文件: 总76页 (文件大小:1489K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
USB2512/12A/12B  
USB2513/13B  
USB2514/14B  
USB2517  
USB 2.0 Hi-Speed  
Hub Controller  
Datasheet  
PRODUCT FEATURES  
General Description  
Features  
The SMSC USB251x hub is a family of low-power, OEM  
configurable, MTT (multi transaction translator)1 hub  
controller IC products for embedded USB solutions. The  
“x” in the part number indicates the number of  
downstream ports available. The SMSC hub supports  
low-speed, full-speed, and hi-speed (if operating as a hi-  
speed hub) downstream devices on all of the enabled  
downstream ports.  
„
USB251xB/xBi products are fully footprint compatible  
with USB251x/xi/xA/xAi products as direct drop-in  
replacements  
Cost savings include using the same PCB components  
and application of USB-IF Compliance by Similarity  
„
„
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Full power management with individual or ganged  
power control of each downstream port  
Fully integrated USB termination and pull-up/pull-  
down resistors  
Supports a single external 3.3 V supply source;  
internal regulators provide 1.2 V or 1.8 V internal  
core voltage  
Onboard 24 MHz crystal driver, ceramic resonator, or  
external 24/48 MHz clock input  
Customizable vendor ID, product ID, and device ID  
4 kilovolts of HBM JESD22-A114F ESD protection  
(powered and unpowered)  
For a summary of the products documented in this  
datasheet, please refer to the Chapter 1, "USB251x Hub  
Family Differences Overview," on page 7.  
„
Highlights  
„
„
„
High performance, low-power, small footprint hub  
controller IC with 2, 3, 4, or 7 downstream ports  
(indicated by the “x” in the part number)  
Fully compliant with the USB 2.0 specification  
Enhanced OEM configuration options available  
through either a single serial I2C® EEPROM, or  
SMBus slave port  
„
„
Supports self- or bus-powered operation  
USB251xB and USB251xBi products support the  
USB Battery Charging specification Rev. 1.1 for  
Charging Downstream Ports (CDP)  
„
„
„
Lead-free RoHS compliant packages:  
36-pin QFN (6x6 mm)  
48-pin QFN (7x7 mm)  
64-pin QFN (9x9 mm)  
„
MultiTRAKTM  
High-performance multiple transaction translator which  
provides one transaction translator per port  
„
„
USB251xi, USB2512Ai, and USB251xBi products  
support the industrial temperature range of -40ºC  
to +85ºC  
USB251xB products support the extended  
commercial temperature range of 0ºC to +85ºC  
„
„
PortMap  
Flexible port mapping and disable sequencing  
PortSwap  
Programmable USB differential-pair pin locations ease  
PCB design by aligning USB signal lines directly to  
connectors  
Applications  
„
PHYBoost  
Programmable USB signal drive strength for recovering  
signal integrity using 4-level driving strength resolution  
„
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LCD monitors and TVs  
Multi-function USB peripherals  
PC motherboards  
Set-top boxes, DVD players, DVR/PVR  
Printers and scanners  
PC media drive bay  
Portable hub boxes  
Mobile PC docking  
Embedded systems  
1.USB2512A/Ai only uses a single transaction translator.  
SMSC USB251x Hub Family  
DATASHEET  
Revision 1.1 (04-26-10)  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
ORDER NUMBERS:  
LEAD-FREE  
ROHS COMPLIANT  
PACKAGE  
TEMPERATURE  
ORDER NUMBERS  
USB2512-AEZG  
PACKAGE SIZE  
RANGE  
0ºC to 70ºC  
USB2512A-AEZG  
USB2513-AEZG  
USB2514-AEZG  
0ºC to 85ºC  
USB2512B-AEZG  
USB2513B-AEZG  
USB2514B-AEZG  
36QFN  
6 x 6 x 0.5 mm  
-40ºC to 85ºC  
USB2512i-AEZG  
USB2512Ai-AEZG  
USB2512Bi-AEZG  
USB2513i-AEZG  
USB2513Bi-AEZG  
USB2514i-AEZG  
USB2514Bi-AEZG  
0ºC to 70ºC  
USB2513-HZH  
USB2514-HZH  
48QFN  
64QFN  
7 x 7 x 0.5 mm  
9 x 9 x 0.5 mm  
-40ºC to 85ºC  
USB2513i-HZH  
USB2514i-HZH  
0ºC to 70ºC  
USB2517-JZX  
USB2517i-JZX  
-40ºC to 85ºC  
THIS PRODUCT MEETS THE HALOGEN MAXIMUM CONCENTRATION VALUES PER IEC61249-2-21.  
FOR ROHS COMPLIANCE AND ENVIRONMENTAL INFORMATION, PLEASE VISIT WWW.SMSC.COM/ROHS.  
80 ARKAY DRIVE, HAUPPAUGE, NY 11788 (631) 435-6000, FAX (631) 273-3123  
Copyright © 2010 SMSC or its subsidiaries. All rights reserved.  
Circuit diagrams and other information relating to SMSC products are included as a means of illustrating typical applications. Consequently, complete information sufficient for  
construction purposes is not necessarily given. Although the information has been checked and is believed to be accurate, no responsibility is assumed for inaccuracies. SMSC  
reserves the right to make changes to specifications and product descriptions at any time without notice. Contact your local SMSC sales office to obtain the latest specifications  
before placing your product order. The provision of this information does not convey to the purchaser of the described semiconductor devices any licenses under any patent  
rights or other intellectual property rights of SMSC or others. All sales are expressly conditional on your agreement to the terms and conditions of the most recently dated  
version of SMSC's standard Terms of Sale Agreement dated before the date of your order (the "Terms of Sale Agreement"). The product may contain design defects or errors  
known as anomalies which may cause the product's functions to deviate from published specifications. Anomaly sheets are available upon request. SMSC products are not  
designed, intended, authorized or warranted for use in any life support or other application where product failure could cause or contribute to personal injury or severe property  
damage. Any and all such uses without prior written approval of an Officer of SMSC and further testing and/or modification will be fully at the risk of the customer. Copies of  
this document or other SMSC literature, as well as the Terms of Sale Agreement, may be obtained by visiting SMSC’s website at http://www.smsc.com. SMSC is a registered  
trademark of Standard Microsystems Corporation (“SMSC”). Product names and company names are the trademarks of their respective holders.  
SMSC DISCLAIMS AND EXCLUDES ANY AND ALL WARRANTIES, INCLUDING WITHOUT LIMITATION ANY AND ALL IMPLIED WARRANTIES OF MERCHANTABILITY,  
FITNESS FOR A PARTICULAR PURPOSE, TITLE, AND AGAINST INFRINGEMENT AND THE LIKE, AND ANY AND ALL WARRANTIES ARISING FROM ANY COURSE  
OF DEALING OR USAGE OF TRADE. IN NO EVENT SHALL SMSC BE LIABLE FOR ANY DIRECT, INCIDENTAL, INDIRECT, SPECIAL, PUNITIVE, OR CONSEQUENTIAL  
DAMAGES; OR FOR LOST DATA, PROFITS, SAVINGS OR REVENUES OF ANY KIND; REGARDLESS OF THE FORM OF ACTION, WHETHER BASED ON CONTRACT;  
TORT; NEGLIGENCE OF SMSC OR OTHERS; STRICT LIABILITY; BREACH OF WARRANTY; OR OTHERWISE; WHETHER OR NOT ANY REMEDY OF BUYER IS HELD  
TO HAVE FAILED OF ITS ESSENTIAL PURPOSE, AND WHETHER OR NOT SMSC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.  
Revision 1.1 (04-26-10)  
2
SMSC USB251x  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Table of Contents  
Chapter 1 USB251x Hub Family Differences Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7  
Chapter 2 General Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8  
Chapter 3 Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10  
Chapter 4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11  
Chapter 5 Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12  
5.1  
5.2  
5.3  
Pin Configurations and Lists (Organized by Package Type) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12  
USB251x Pin Descriptions (Grouped by Function). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22  
Buffer Type Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27  
Chapter 6 LED Usage Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29  
6.1  
LED Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29  
6.1.1  
6.1.2  
USB Mode 14-Wire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29  
LED Mode Speed Indication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29  
Chapter 7 Battery Charging Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31  
7.1  
7.2  
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31  
USB Battery Charging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31  
7.2.1  
Battery Charging Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32  
7.3.1 Battery Charging enabled via EEPROM or SMBus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32  
Special Behavior of PRTPWR Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31  
7.3  
Chapter 8 Configuration Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33  
8.1  
8.2  
8.3  
Hub . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33  
8.1.1  
8.1.2  
8.1.3  
Hub Configuration Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33  
SMBus or EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33  
VBus Detect. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34  
EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34  
8.2.1  
8.2.2  
8.2.3  
Internal Register Set (Common to EEPROM and SMBus) . . . . . . . . . . . . . . . . . . . . . . . 35  
I C EEPROM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52  
In-Circuit EEPROM Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52  
2
SMBus Slave Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53  
8.3.1  
8.3.2  
8.3.3  
8.3.4  
8.3.5  
8.3.6  
8.3.7  
8.3.8  
8.3.9  
SMBus Slave Addresses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53  
Bus Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53  
Invalid Protocol Response Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54  
General Call Address Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54  
Slave Device Time-Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54  
Stretching the SCLK Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54  
SMBus Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54  
Bus Reset Sequence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54  
SMBus Alert Response Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55  
8.4  
8.5  
8.6  
Default Configuration Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55  
Default Strapping Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55  
Strap Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55  
8.6.1  
8.6.2  
8.6.3  
Non-Removable Strap Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55  
Internal Pull-Down (IPD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56  
LED Strap Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56  
8.7  
Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57  
SMSC USB251x  
3
Revision 1.1 (04-26-10)  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
8.7.1  
8.7.2  
External Hardware RESET_N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57  
USB Bus Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60  
Chapter 9 DC Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61  
9.1  
9.2  
Maximum Guaranteed Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61  
Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61  
9.2.1  
Package Thermal Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68  
Chapter 10 AC Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69  
10.1 Oscillator/Crystal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69  
10.2 Ceramic Resonator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70  
10.3 External Clock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70  
10.3.1 SMBus Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70  
2
10.3.2 I C EEPROM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70  
10.3.3 USB 2.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70  
Chapter 11 Package Outlines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71  
11.1 Tape and Reel Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74  
Revision 1.1 (04-26-10)  
4
SMSC USB251x  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
List of Tables  
Table 1.1 36-pin QFN (6x6x0.5 mm) RoHS Compliant Part Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . 7  
Table 1.2 48-pin QFN (7x7x0.5 mm) RoHS Compliant Part Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . 7  
Table 1.3 64-pin QFN (9x9x0.5 mm) RoHS Compliant Part Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . 7  
Table 2.1 Summary of Compatibilities between USB251xB/xBi and USB251x/xi/xA/xAi Products. . . . . . 9  
Table 5.1 Pin List in Alphabetical Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18  
Table 5.2 USB251x Pin Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22  
Table 5.3 Buffer Type Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27  
Table 8.1 Hub Configuration Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33  
Table 8.2 Internal Default, EEPROM and SMBus Register Memory Map. . . . . . . . . . . . . . . . . . . . . . . . 35  
Table 8.3 PortMap Register for Ports 1 & 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48  
Table 8.4 PortMap Register for Ports 3 & 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49  
Table 8.5 PortMap Register for Ports 5 & 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50  
Table 8.6 PortMap Register for Port 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51  
Table 8.7 Summary of Strap Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55  
Table 8.8 Reset_N Timing for Default/Strap Option Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58  
Table 8.9 Reset_N Timing for EEPROM Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58  
Table 8.10 Reset_N Timing for SMBus Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59  
Table 9.1 DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62  
Table 9.2 Supply Current Unconfigured: Hi-Speed Host (ICCINTHS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63  
Table 9.3 Supply Current Unconfigured: Full-Speed Host (ICCINTFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64  
Table 9.4 Supply Current Configured: Hi-Speed Host (IHCH1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64  
Table 9.5 Supply Current Configured: Full-Speed Host (IFCC1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65  
Table 9.6 USB251x/xi/xA/xAi Supply Current Suspend (ICSBY). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66  
Table 9.7 USB251xB/xBi Supply Current Suspend (ICSBY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66  
Table 9.8 USB251x/xi/xA/xAi Supply Current Reset (ICRST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66  
Table 9.9 USB251xB/xBi Supply Current Reset (ICRST). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67  
Table 9.10 Pin Capacitance for USB251x, USB251xi, USB251xA, USB251xAi . . . . . . . . . . . . . . . . . . . . 67  
Table 9.11 Pin Capacitance for USB251xB and USB251xBi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67  
Table 9.12 Package Thermal Resistance Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68  
Table 9.13 Legend. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68  
Table 10.1 Crystal Circuit Legend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69  
Table 11.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77  
SMSC USB251x  
5
Revision 1.1 (04-26-10)  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
List of Figures  
Figure 4.1 USB251x Hub Family Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11  
Figure 5.1 2-Port 36-Pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12  
Figure 5.2 3-Port 36-pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13  
Figure 5.3 4-Port 36-pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14  
Figure 5.4 3-Port 48-Pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15  
Figure 5.5 4-Port 48-Pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16  
Figure 5.6 7-Port 64-Pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17  
Figure 6.1 Dual Color LED Implementation Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29  
Figure 7.1 Battery Charging via External Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31  
Figure 8.1 Block Write. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53  
Figure 8.2 Block Read. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54  
Figure 8.3 Non-Removable Pin Strap Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56  
Figure 8.4 Pin Strap Option with IPD Pin Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56  
Figure 8.5 LED Pin Strap Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56  
Figure 8.6 Reset_N Timing for Default/Strap Option Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57  
Figure 8.7 Reset_N Timing for EEPROM Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58  
Figure 8.8 Reset_N Timing for SMBus Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59  
Figure 9.1 Supply Rise Time Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62  
Figure 10.1 Typical Crystal Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69  
Figure 10.2 Formula to Find the Value of C1 and C2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69  
Figure 10.3 Ceramic Resonator Usage with SMSC IC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70  
Figure 11.1 36-Pin QFN, 6x6 mm Body, 0.5 mm Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71  
Figure 11.2 48-Pin QFN, 7x7 mm Body, 0.5 mm Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72  
Figure 11.3 64-Pin QFN, 9x9 mm Body, 0.5 mm Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73  
Figure 11.4 36-Pin Package Tape Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74  
Figure 11.5 48-Pin Package Tape Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75  
Figure 11.6 36-Pin and 48-Pin Package Reel Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76  
Revision 1.1 (04-26-10)  
6
SMSC USB251x  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Chapter 1 USB251x Hub Family Differences Overview  
Table 1.1 36-pin QFN (6x6x0.5 mm) RoHS Compliant Part Numbers  
Part  
Number  
Down-  
stream  
ports  
True  
Speed  
Battery  
Charging  
Lower Power  
Consumption  
LED Port  
Indicators  
Clock  
(MHz)  
0ºC  
to  
70ºC  
0ºC  
to  
85ºC  
-40ºC  
to  
85ºC  
24  
24  
USB2512  
2
2
3
USB2512A*  
USB2512i  
USB2512Ai*  
3
24  
24  
24  
24  
24  
24  
24  
24  
24  
24  
USB2512B  
USB2512Bi  
USB2513  
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
USB2513i  
USB2513B  
USB2513Bi  
USB2514  
3
3
3
3
3
4
USB2514i  
USB2514B  
USB2514Bi  
4
4
3
3
3
3
4
Table 1.2 48-pin QFN (7x7x0.5 mm) RoHS Compliant Part Numbers  
Part  
Number  
Down-  
stream  
ports  
True  
Speed  
Battery  
Charging  
Lower Power  
Consumption  
LED Port  
Indicators  
Clock  
(MHz)  
0ºC  
to  
70ºC  
0ºC  
to  
85ºC  
-40ºC  
to  
85ºC  
USB2513  
USB2513i  
USB2514  
USB2514i  
3
3
4
4
3
3
3
3
3
3
3
3
24/48  
24/48  
24/48  
24/48  
3
3
3
3
3
Table 1.3 64-pin QFN (9x9x0.5 mm) RoHS Compliant Part Numbers  
Part  
Number  
Down-  
stream  
ports  
True  
Speed  
Battery  
Charging  
Lower Power  
Consumption  
LED Port  
Indicators  
Clock  
(MHz)  
0ºC  
to  
70ºC  
0ºC  
to  
85ºC  
-40ºC  
to  
85ºC  
USB2517  
USB2517i  
7
7
3
3
3
3
24  
24  
3
3
Note 1.1 *USB2512A/Ai only uses a single transaction translator, whereas all other parts use a multi  
transactions translator.  
SMSC USB251x  
7
Revision 1.1 (04-26-10)  
DATASHEET  
USB 2.0 High-Speed 2-Port Hub Controller  
Datasheet  
Chapter 2 General Description  
The SMSC USB251x hub family is a group of low-power, OEM configurable, MTT (multi  
transaction translator)1 hub controller IC’s with downstream ports for embedded USB solutions.  
The SMSC USB251x hub family is fully compliant with the USB 2.0 specification. Each of the  
SMSC hub controllers can attach to an upstream port as a full-speed hub or as a full-/hi-speed  
hub. The SMSC hub controllers support low-speed, full-speed, and hi-speed (if operating as a  
hi-speed hub) downstream devices on all of the enabled downstream ports.  
All required resistors on the USB ports are integrated into the hub. This includes all series  
termination resistors on D+ and D– pins and all required pull-down and pull-up resistors on D+  
and D– pins. The over-current sense inputs for the downstream facing ports have internal pull-  
up resistors.  
The USB251x hub family includes programmable features such as:  
MultiTRAKTM Technology which utilizes a dedicated TT per port to maintain consistent full-  
speed data throughput regardless of the number of active downstream connections. MultiTRAKTM  
outperforms conventional USB 2.0 hubs with a single TT in USB full-speed data transfers.  
PortMap which provides flexible port mapping and disable sequences. The downstream ports of  
a USB251x hub can be reordered or disabled in any sequence to support multiple platform  
designs with minimum effort. For any port that is disabled, the USB251x hub controllers  
automatically reorder the remaining ports to match the USB host controller’s port numbering  
scheme.  
PortSwap which adds per-port programmability to USB differential-pair pin locations. PortSwap  
allows direct alignment of USB signals (D+/D-) to connectors to avoid uneven trace length or  
crossing of the USB differential signals on the PCB.  
PHYBoost which enables 4 programmable levels of USB signal drive strength in downstream  
port transceivers. PHYBoost attempts to restore USB signal integrity.  
OEM Selectable Features  
A default configuration is available in each of the SMSC USB251x hub controllers following a  
reset. This configuration may be sufficient for most applications. Strapping option pins make it  
possible to modify a sub-set of the configuration options.  
The USB251x hub controllers may be configured by an external EEPROM or a microcontroller.  
When using the microcontroller interface, the hub appears as an SMBus slave device. If the hub  
is pin-strapped for external EEPROM configuration but no external EEPROM is present, then a  
value of ‘0’ will be written to all configuration data bit fields (the hub will attach to the host with  
all ‘0’ values).  
The USB251x hub family supports OEM selectable features including:  
„
Optional OEM configuration via I2C EEPROM or via the industry standard SMBus interface  
from an external SMBus host or microcontroller.  
„
„
Supports compound devices on a port-by-port basis.  
Selectable over-current sensing and port power control on an individual or ganged basis to  
match the OEM’s choice of circuit board component selection.  
„
„
„
„
Customizable vendor ID, product ID, and device ID.  
Configurable delay time for filtering the over-current sense inputs.  
Configurable downstream port power-on time reported to the host.  
Supports indication of the maximum current that the hub consumes from the USB upstream  
port.  
„
Supports Indication of the maximum current required for the hub controller.  
1.USB2512A/2Ai only uses a single transaction translator.  
Revision 1.1 (04-26-10)  
8
SMSC USB251x  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
„
„
Supports custom string descriptors (up to 31 characters):  
- Product string  
- Manufacturer string  
- Serial number string  
When available, pin selectable options for default configuration may include:  
-Downstream ports as non-removable ports  
-Downstream ports as disabled ports  
-Downstream port power control and over-current detection on a ganged or individual basis  
-USB signal drive strength  
-USB differential pair pin location  
„
„
For more information, please contact your sales representative to obtain a copy of the latest Battery  
Charging white paper.  
USB251xB/xBi products are fully footprint compatible with USB251x/xi/xA/xAi products:  
-pin-compatible  
-direct drop-in replacement  
-use the same PCB components  
-USB-IF Compliance by Similarity for ease of use and a complete cost reduction solution  
-PIDs, DIDs, and other register defaults may differ and can be configured to match the OEM’s needs. Please  
see Table 8.2, "Internal Default, EEPROM and SMBus Register Memory Map" for details.  
Table 2.1 Summary of Compatibilities between USB251xB/xBi and USB251x/xi/xA/xAi Products  
Part  
Number  
Drop-in  
Replacement  
PACKAGE  
USB2512  
USB2512i  
USB2512A  
USB2512Ai  
USB2513  
USB2513i  
USB2514  
USB2514i  
USB2512B  
USB2512Bi  
USB2512B  
USB2512Bi  
USB2513B  
USB2513Bi  
USB2514B  
USB2514Bi  
36QFN  
SMSC USB251x  
9
Revision 1.1 (04-26-10)  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Chapter 3 Acronyms  
I2C®: Inter-Integrated Circuit1  
OCS: Over-Current Sense  
PCB: Printed Circuit Board  
PHY: Physical Layer  
PLL: Phase-Locked Loop  
QFN: Quad Flat No Leads  
RoHS: Restriction of Hazardous Substances Directive  
SCL: Serial Clock  
SIE: Serial Interface Engine  
SMBus: System Management Bus  
TT: Transaction Translator  
1.I2C is a registered trademark of Philips Corporation.  
Revision 1.1 (04-26-10)  
10  
SMSC USB251x  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Chapter 4 Block Diagram  
To EEPROM or  
SMBus Master  
To Upstream  
VBUS  
Upstream  
USB Data  
24 MHz  
Crystal  
SCL  
SDA  
3.3 V  
Serial  
Interface  
Bus-  
Power  
Detect/  
Vbus Pulse  
Regulator  
PLL  
Upstream  
PHY  
Serial  
Interface  
Engine  
Repeater  
Controller  
3.3 V  
TT  
#x  
TT  
#1  
Port  
Controller  
...  
Regulator  
CRFILT  
Routing & Port Re-Ordering Logic  
Port #1  
Port #x  
OC Sense  
Switch Driver/  
LED Drivers  
OC Sense  
PHY#1  
PHY#x  
...  
Switch Driver/  
LED Drivers  
USB Data  
OC  
USB Data  
Port  
OC  
Port  
Downstream  
Sense  
Switch/  
LED  
Sense  
Switch/  
LED  
Downstream  
Power  
Power  
Drivers  
Drivers  
The ‘x’ indicates the number of available downstream ports: 2, 3, 4, or 7.  
Figure 4.1 USB251x Hub Family Block Diagram  
Note 4.1 USB2512A/USB2512Ai only supports a single transaction translator.  
Note 4.2 The LED port indicators only apply to USB2513/13i/14/14i (48QFN only) and USB2517/17i.  
SMSC USB251x  
11  
Revision 1.1 (04-26-10)  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Chapter 5 Pin Descriptions  
This chapter is organized by a set of pin configurations (organized by package type) followed by a  
corresponding pin list organized alphabetically. A comprehensive and detailed description list of each  
signal (named in the pin list) is organized by function in Table 5.2, “USB251x Pin Descriptions,” on  
page 22. Please refer to Table 5.3, “Buffer Type Descriptions,” on page 27 for a list of buffer types.  
The “N” symbol in the signal name indicates that the active, or asserted, state occurs when the signal  
is at a low voltage level. When “N” is not present after the signal name, the signal is asserted when it  
is at the high voltage level. The terms assertion and negation are used exclusively. This is done to  
avoid confusion when working with a mixture of “active low” and “active high” signals. The term assert,  
or assertion, indicates that a signal is active, independent of whether that level is represented by a  
high or low voltage. The term negate, or negation, indicates that a signal is inactive.  
5.1  
Pin Configurations and Lists (Organized by Package Type)  
SUSP_IND / LOCAL_PWR / NON_REM[0]  
NC  
28  
29  
30  
31  
32  
33  
34  
35  
36  
18  
17  
16  
15  
14  
13  
12  
11  
10  
VDD33  
USBDM_UP  
USBDP_UP  
XTALOUT  
XTALIN / CLKIN  
PLLFILT  
OCS_N[2]  
PRTPWR[2] / BC_EN[2]*  
VDD33  
SMSC  
USB2512/12A/12B  
USB2512i/12Ai/12Bi  
(Top View QFN-36)  
Ground Pad  
(must be connected to VSS)  
CRFILT  
OCS_N[1]  
PRTPWR[1] / BC_EN[1]*  
TEST  
RBIAS  
VDD33  
VDD33  
Indicates pins on the bottom of the device.  
Figure 5.1 2-Port 36-Pin QFN  
Note: *Battery charging enable (BC_EN) is only available in the USB251xB/Bi.  
Revision 1.1 (04-26-10)  
12  
SMSC USB251x  
DATASHEET  
 
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
SUSP_IND / LOCAL_PWR / NON_REM[0]  
PRTPWR[3] / BC_EN[3]*  
OCS_N[2]  
28  
29  
30  
31  
32  
33  
34  
35  
36  
18  
17  
16  
15  
14  
13  
12  
11  
10  
VDD33  
USBDM_UP  
USBDP_UP  
XTALOUT  
XTALIN / CLKIN  
PLLFILT  
PRTPWR[2] / BC_EN[2]*  
VDD33  
SMSC  
USB2513/13i  
USB2513B/13Bi  
(Top View QFN-36)  
CRFILT  
OCS_N[1]  
PRTPWR[1] / BC_EN[1]*  
TEST  
Ground Pad  
(must be connected to VSS)  
RBIAS  
VDD33  
VDD33  
Indicates pins on the bottom of the device.  
Figure 5.2 3-Port 36-pin QFN  
Note: *Battery charging enable (BC_EN) is only available in the USB251xB/Bi.  
SMSC USB251x  
13  
Revision 1.1 (04-26-10)  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
SUSP_IND / LOCAL_PWR / NON_REM[0]  
PRTPWR[3] / BC_EN[3]*  
OCS_N[2]  
28  
29  
30  
31  
32  
33  
34  
35  
36  
18  
17  
16  
15  
14  
13  
12  
11  
10  
VDD33  
USBDM_UP  
USBDP_UP  
XTALOUT  
XTALIN / CLKIN  
PLLFILT  
PRTPWR[2] / BC_EN[2]*  
VDD33  
SMSC  
USB2514/14i  
USB2514B/14Bi  
(Top View QFN-36)  
CRFILT  
OCS_N[1]  
PRTPWR[1] / BC_EN[1]*  
TEST  
Ground Pad  
(must be connected to VSS)  
RBIAS  
VDD33  
VDD33  
Indicates pins on the bottom of the device.  
Figure 5.3 4-Port 36-pin QFN  
Note: *Battery charging enable (BC_EN) is only available in the USB251xB/Bi.  
Revision 1.1 (04-26-10)  
14  
SMSC USB251x  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
LED_A_N[1] / PRTSWP[1]  
LED_B_N[2] / BOOST[1]  
LED_A_N[3] / PRTSWP[3]  
LED_B_N[3] / GANG_EN  
PRTPWR[3]  
OCS_N[2]  
37  
38  
39  
40  
41  
42  
43  
44  
45  
46  
47  
48  
24  
23  
22  
21  
20  
19  
18  
17  
16  
15  
14  
13  
PRTPWR_POL  
SUSP_IND / LOCAL_PWR / NON_REM[0]  
SEL48  
VDD33  
SMSC  
USB2513 / USB2513i  
(Top View QFN-48)  
USBDM_UP  
USBDP_UP  
XTALOUT  
XTALIN / CLKIN  
PLLFILT  
PRTPWR[2]  
VDD33  
CRFILT  
OCS_N[1]  
PRTPWR[1]  
TEST  
Ground Pad  
(must be connected to VSS)  
RBIAS  
VDD33  
NC  
Indicates pins on the bottom of the device.  
Figure 5.4 3-Port 48-Pin QFN  
SMSC USB251x  
15  
Revision 1.1 (04-26-10)  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
LED_A_N[1] / PRTSWP[1]  
LED_B_N[2] / BOOST[1]  
LED_A_N[3] / PRTSWP[3]  
LED_B_N[3] / GANG_EN  
PRTPWR[3]  
37  
38  
39  
40  
41  
42  
43  
44  
45  
46  
47  
48  
24  
23  
22  
21  
20  
19  
18  
17  
16  
15  
14  
13  
PRTPWR_POL  
SUSP_IND / LOCAL_PWR / NON_REM[0]  
SEL48  
VDD33  
OCS_N[2]  
SMSC  
USB2514 / USB2514i  
(Top View QFN-48)  
USBDM_UP  
USBDP_UP  
XTALOUT  
XTALIN / CLKIN  
PLLFILT  
PRTPWR[2]  
VDD33  
CRFILT  
OCS_N[1]  
PRTPWR[1]  
Ground Pad  
(must be connected to VSS)  
RBIAS  
TEST  
VDD33  
LED_A_N[4] / PRTSWP[4]  
Indicates pins on the bottom of the device.  
Figure 5.5 4-Port 48-Pin QFN  
Revision 1.1 (04-26-10)  
16  
SMSC USB251x  
DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
LED_A_N[2] / PRTSWP[2]  
LED_B_N[1] / BOOST[0]  
LED_A_N[1] / PRTSWP[1]  
VDD33  
LED_B_N[4]  
LED_A_N[5] / PRTSWP[5]  
PRTPWR[5]  
PRTPWR[1]  
OCS_N[1]  
49  
50  
51  
52  
53  
54  
55  
56  
57  
58  
59  
60  
61  
62  
63  
64  
32  
31  
30  
29  
28  
27  
26  
25  
24  
23  
22  
21  
20  
19  
18  
17  
USBDM_DN[6] / PRT_DIS_M[6]  
USBDP_DN[6] / PRT_DIS_P[6]  
USBDM_DN[7] / PRT_DIS_M[7]  
USBDP_DN[7] / PRT_DIS_P[7]  
VDD33  
OCS_N[2]  
PRTPWR[2]  
CRFILT  
SMSC  
USB2517/17i  
(Top View QFN-64)  
VDD33  
USBDM_UP  
PRTPWR[3]  
OCS_N[3]  
USBDP_UP  
XTALOUT  
OCS_N[4]  
XTALIN / CLKIN  
PRTPWR[4]  
TEST  
PLLFILT  
Ground Pad  
(must be connected to VSS)  
RBIAS  
LED_B_N[5]  
LED_A_N[6] / PRTSWP[6]  
VDD33  
Indicates pins on the bottom of the device.  
Figure 5.6 7-Port 64-Pin QFN  
SMSC USB251x  
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USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Table 5.1 Pin List in Alphabetical Order  
PIN NUMBERS  
36 QFN  
48QFN  
64 QFN  
SYMBOL  
BC_EN[1]  
NAME  
Battery  
Charging Strap  
Option  
-
-
12  
16  
-
-
12  
16  
18  
-
-
-
12  
16  
18  
20  
-
-
-
-
BC_EN[2]  
BC_EN[3]  
BC_EN[4]  
BOOST[0]  
BOOST[1]  
-
-
PHY Boost  
Strapping  
Option  
-
-
36  
24  
50  
48  
CFG_SEL[0]  
CFG_SEL[1]  
CFG_SEL[2]  
CLKIN  
Configuration  
Programming  
Selection  
24  
25  
-
31  
32  
33  
45  
41  
42  
13  
61  
External Clock  
Input  
33  
CRFILT  
Core Regulator  
Filter Capacitor  
14  
-
17  
22  
25  
34  
GANG_EN  
Ganged Port  
Power Strap  
Option  
Ground Pad  
HS_IND  
Exposed Pad  
Tied to Ground  
(VSS)  
ePad  
Hi-Speed  
Upstream Port  
Indicator  
25  
32  
42  
LED_A_N[1]  
LED_A_N[2]  
LED_A_N[3]  
LED_A_N[4]  
LED_A_N[5]  
LED_A_N[6]  
LED_A_N[7]  
LED_B_N[1]  
LED_B_N[2]  
LED_B_N[3]  
LED_B_N[4]  
LED_B_N[5]  
LED_B_N[6]  
LED_B_N[7]  
LOCAL_PWR  
Port LED  
Indicator  
-
-
-
37  
25  
23  
51  
49  
47  
33  
31  
17  
15  
50  
48  
34  
32  
18  
16  
14  
45  
-
13  
-
-
-
Enhanced  
Indicator  
Port LED  
-
-
-
36  
24  
22  
-
12  
-
-
-
Local Power  
Detection  
28  
39  
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DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Table 5.1 Pin List in Alphabetical Order (continued)  
PIN NUMBERS  
36 QFN  
48QFN  
64 QFN  
SYMBOL  
NAME  
NC  
NC  
NC  
NC  
NC  
NC  
NC  
NC  
No Connect  
6
7
-
-
-
-
8
9
11  
-
-
-
-
-
-
-
18  
19  
11  
12  
13  
27  
28  
8
9
-
-
-
20  
21  
-
NON_REM[0]  
NON_REM[1]  
Non-  
28  
22  
39  
29  
45  
40  
Removable  
Port Strap  
Option  
OCS_N[1]  
OCS_N[2]  
OCS_N[3]  
OCS_N[4]  
OCS_N[5]  
OCS_N[6]  
OCS_N[7]  
PLLFILT  
Over-Current  
Sense  
13  
17  
16  
20  
26  
28  
27  
22  
21  
35  
38  
37  
62  
-
19  
-
21  
-
28  
-
-
-
PLL Regulator  
Filter Capacitor  
34  
46  
PRT_DIS_M[1]  
PRT_DIS_M[2]  
PRT_DIS_M[3]  
PRT_DIS_M[4]  
PRT_DIS_M[5]  
PRT_DIS_M[6]  
PRT_DIS_M[7]  
PRT_DIS_P[1]  
PRT_DIS_P[2]  
PRT_DIS_P[3]  
PRT_DIS_P[4]  
PRT_DIS_P[5]  
PRT_DIS_P[6]  
PRT_DIS_P[7]  
Downstream  
Port Disable  
Strap Option  
-
-
-
1
3
6
-
8
-
8
-
-
-
11  
53  
55  
Port Disable  
-
-
-
2
4
7
-
9
-
9
-
-
-
12  
54  
56  
SMSC USB251x  
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Datasheet  
Table 5.1 Pin List in Alphabetical Order (continued)  
PIN NUMBERS  
36 QFN  
48QFN  
64 QFN  
SYMBOL  
NAME  
PRTPWR[1]  
PRTPWR[2]  
PRTPWR[3]  
PRTPWR[4]  
PRTPWR[5]  
PRTPWR[6]  
PRTPWR[7]  
PRTPWR_POL  
USB Port  
Power Enable  
12  
16  
15  
19  
21  
29  
26  
23  
20  
30  
39  
36  
-
-
18  
-
20  
-
27  
-
-
-
Port Power  
Polarity  
-
38  
Strapping  
PRTSWP[1]  
PRTSWP[2]  
PRTSWP[3]  
PRTSWP[4]  
PRTSWP[5]  
PRTSWP[6]  
PRTSWP[7]  
RBIAS  
Port Swap  
Strapping  
Option  
-
-
-
37  
25  
23  
51  
49  
47  
33  
31  
17  
15  
63  
-
13  
-
-
-
USB  
Transceiver  
Bias  
35  
47  
RESET_N  
SCL  
Reset Input  
Serial Clock  
26  
24  
22  
34  
31  
29  
43  
41  
40  
SDA  
Serial Data  
Signal  
Select 48 MHz  
Clock Input  
-
40  
31  
-
SEL48  
SMBCLK  
System  
Management  
Bus Clock  
24  
41  
SMBDATA  
SUSP_IND  
Server  
Message Block  
Data Signal  
22  
28  
29  
39  
40  
45  
Active/Suspend  
Status Indicator  
TEST  
Test Pin  
11  
30  
31  
14  
42  
43  
19  
58  
59  
USBDM_UP  
USBDP_UP  
USB Bus Data  
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Datasheet  
Table 5.1 Pin List in Alphabetical Order (continued)  
PIN NUMBERS  
36 QFN  
48QFN  
64 QFN  
SYMBOL  
NAME  
USBDM_DN[1] Hi-Speed USB  
1
3
Data  
USBDM_DN[2]  
USBDM_DN[3]  
USBDM_DN[4]  
USBDM_DN[5]  
USBDM_DN[6]  
USBDM_DN[7]  
USBDP_DN[1]  
USBDP_DN[2]  
USBDP_DN[3]  
USBDP_DN[4]  
USBDP_DN[5]  
USBDP_DN[6]  
USBDP_DN[7]  
-
6
-
8
-
8
-
-
-
11  
53  
55  
2
4
-
7
-
9
-
9
-
-
-
12  
54  
56  
44  
VBUS_DET  
Upstream  
VBUS Power  
Detection  
27  
35  
VDD33  
VDD33  
VDD33  
VDD33  
VDD33  
VDD33  
VDD33  
XTALIN  
XTALOUT  
3.3 V Power  
5
10  
15  
23  
29  
36  
18  
30  
41  
48  
24  
46  
52  
57  
64  
61  
60  
-
Crystal Input  
33  
32  
45  
44  
Crystal Output  
SMSC USB251x  
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5.2  
USB251x Pin Descriptions (Grouped by Function)  
Table 5.2 USB251x Pin Descriptions  
BUFFER  
TYPE  
SYMBOL  
DESCRIPTION  
UPSTREAM USB 2.0 INTERFACES  
USB Data  
USBDM_UP  
USBDP_UP  
IO-U  
These pins connect to the upstream USB bus data signals (host, port, or  
upstream hub).  
VBUS_DET  
I/O12  
Detect Upstream VBUS Power  
Detects the state of Upstream VBUS power. The SMSC hub monitors  
VBUS_DET to determine when to assert the internal D+ pull-up resistor which  
signals a connect event.  
When designing a detachable hub, this pin should be connected to VBUS on  
the upstream port via a 2 to 1 voltage divider.  
For self-powered applications with a permanently attached host, this pin must  
be connected to 3.3 V (typically VDD33).  
DOWNSTREAM USB 2.0 INTERFACES  
USBDP_DN[x:1]/  
PRT_DIS_P[x:1]  
IO-U  
Hi-Speed USB Data  
These pins connect to the downstream USB peripheral devices attached to  
the hub’s port. To disable, pull up with a 10 K resistor to 3.3 V.  
USBDM_DN[x:1]/  
PRT_DIS_M[x:1]  
Downstream Port Disable Strap Option  
If this strap is enabled by package and configuration settings (see Table 8.1,  
"Hub Configuration Options"), then this pin will be sampled at RESET_N  
negation to determine if the port is disabled.  
To disable a port, pull up both PRT_DIS_M[x:1] and PRT_DIS_P[x:1] pins  
corresponding to the port numbers.  
PRTPWR[x:1] /  
O12  
USB Power Enable  
Enables power to USB peripheral devices downstream.  
When PRTPWR_POL pin is unavailable, the hub supports active high power  
controllers only.  
When PRTPWR_POL pin is available, the active signal level of the PRTPWR  
pins is determined by the power polarity strapping function of the  
PRTPWR_POL pin.  
BC_EN[x]  
IPD  
Battery Charging Strap Option  
*This feature is only available on USB251xB/Bi.  
If this strap is enabled by package and configuration settings, (see Table 8.1,  
"Hub Configuration Options"), this pin will be sampled at RESET_N negation  
to determine if ports [x:1] support the battery charging protocol (and thus the  
supporting external port power controllers) that would enable a device to draw  
the currents per the USB battery charging specification.  
BC_EN[x] = 1: Battery charging feature is supported for port x  
BC_EN[x] = 0: Battery charging feature is not supported for  
port x  
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Datasheet  
Table 5.2 USB251x Pin Descriptions (continued)  
DESCRIPTION  
BUFFER  
TYPE  
SYMBOL  
DOWNSTREAM USB 2.0 INTERFACES (continued)  
LED_A_N[x:1] /  
I/O12  
Port LED Indicators  
This pin will be active low when LED support is enabled via EEPROM or  
SMBus.  
Port Swap Strapping Option  
PRTSWP[x:1]  
If this strap is enabled by package and configuration settings (see Table 8.1,  
"Hub Configuration Options"), this pin will be sampled at RESET_N negation  
to determine the electrical connection polarity of the downstream USB port  
pins (USB_DP and USB_DM).  
Also, the active state of the LED will be determined as follows:  
‘0’ = Port polarity is normal, LED is active high.  
‘1’ = Port polarity (USB_DP and USB_DM) is swapped, LED is active low.  
Enhanced Indicator Port LED for ports 4-7  
LED_B_N[7:4]  
I/O12  
I/O12  
Enhanced indicator LED for ports 4-7. This pin will be active low when LED  
support is enabled via EEPROM or SMBus.  
LED_B_N[3] /  
GANG_EN  
Enhanced Indicator Port LED for port 3  
This pin will be active low when LED support is enabled via EEPROM or  
SMBus.  
Ganged Power and Over-current strap option  
This signal selects between ganged or individual port power and over-current  
sensing. If this strap is enabled by package and configuration settings (see  
Table 8.1, "Hub Configuration Options"), this pin will be sampled at RESET_N  
negation to determine the mode as follows:  
‘0’ = Individual sensing and switching, LED_B_N[3] is active high.  
‘1’ = Ganged sensing and switching, LED_B_N[3] is active low.  
SMSC USB251x  
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Table 5.2 USB251x Pin Descriptions (continued)  
BUFFER  
SYMBOL  
TYPE  
DESCRIPTION  
DOWNSTREAM USB 2.0 INTERFACES (continued)  
LED_B_N[2:1] /  
I/O12  
Enhanced Indicator Port LED for ports 1 and 2  
Enhanced indicator LED for ports 1 and 2. This pin will be active low when  
LED support is enabled via EEPROM or SMBus.  
If this strap option is enabled by package and configuration settings (see  
Table 8.1, "Hub Configuration Options"), this pin will be sampled at RESET_N  
negation to determine if all PHY ports (upstream and downstream) operate at  
a normal or boosted electrical level. Also, the active state of the LEDs will be  
determined as follows:  
BOOST[1:0]  
See Section 8.2.1.27, "Register F6h: Boost_Up," on page 45 and Section  
8.2.1.29, "Register F8h: Boost_4:0," on page 46 for more information.  
BOOST[1:0] = BOOST_IOUT[1:0]  
BOOST[1:0] = ‘00’,  
LED_B_N[2] is active high,  
LED_B_N[1] is active high.  
BOOST[1:0] = ‘01’,  
LED_B_N[2] is active high,  
LED_B_N[1] is active low.  
BOOST[1:0] = ‘10’,  
LED_B_N[2] is active low,  
LED_B_N[1] is active high.  
BOOST[1:0] = ‘11’,  
LED_B_N[2] is active low,  
LED_B_N[1] is active low.  
PRTPWR_POL  
IPU  
Port Power Polarity Strapping  
Port Power Polarity strapping determination for the active signal polarity of  
the [x:1]PRTPWR pins.  
While RESET_N is asserted, the logic state of this pin will (through the use  
of internal combinatorial logic) determine the active state of the PRTPWR  
pins in order to ensure that downstream port power is not inadvertently  
enabled to inactive ports during a hardware reset.  
When RESET_N is negated, the logic value will be latched internally, and will  
retain the active signal polarity for the PRTPWR[x:1] pins.  
‘1’ = PRTPWR[x:1]_P/N pins have an active ‘high’ polarity  
‘0’ = PRTPWR[x:1]_P/N pins have an active ‘low’ polarity  
Warning: Active low port power controllers may glitch the downstream port  
power when the system power is first applied. Care should be taken when  
designing with active low components.  
When PRTPWR_POL is not an available pin on the package, the hub will only  
support active high power controllers.  
OCS_N[x:1]  
RBIAS  
IPU  
I-R  
Over-Current Sense  
Input from external current monitor indicating an over-current condition.  
USB Transceiver Bias  
A 12.0 kΩ (+/- 1%) resistor is attached from ground to this pin to set the  
transceiver’s internal bias settings.  
Revision 1.1 (04-26-10)  
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Datasheet  
Table 5.2 USB251x Pin Descriptions (continued)  
BUFFER  
TYPE  
SYMBOL  
DESCRIPTION  
SERIAL PORT INTERFACES  
SDA /  
I/OSD12  
Serial Data signal (SDA)  
Server Message Block Data signal (SMBDATA)  
Non-removable Port Strap Option  
SMBDATA /  
NON_REM[1]  
If this strap is enabled by package and configuration settings (see Table 8.1),  
this pin will be sampled (in conjunction with LOCAL_PWR / SUSP_IND /  
NON_REM[0]) at RESET_N negation to determine if ports [7:1] contain  
permanently attached (non-removable) devices:  
NON_REM[1:0] = ‘00’, All ports are removable.  
NON_REM[1:0] = ‘01’, Port 1 is non-removable.  
NON_REM[1:0] = ‘10’, Ports 1 & 2 are non-removable.  
NON_REM[1:0] = ‘11’, When available, ports 1 2 & 3 are non-removable.  
RESET Input  
RESET_N  
IS  
The system can reset the chip by driving this input low. The minimum active  
low pulse is 1 μs.  
SCL /  
I/OSD12  
Serial Clock (SCL)  
System Management Bus Clock (SMBCLK)  
SMBCLK /  
CFG_SEL[0]  
Configuration Select: The logic state of this multifunction pin is internally  
latched on the rising edge of RESET_N (RESET_N negation), and will  
determine the hub configuration method as described in Table 8.1, "Hub  
Configuration Options".  
HS_IND /  
I/O12  
Hi-Speed Upstream Port Indicator  
HS_IND: Hi-speed Indicator for upstream port connection speed.  
The active state of the LED will be determined as follows:  
CFG_SEL[1] = ‘0’,  
HS_IND is active high,  
CFG_SEL[1] = ‘1’,  
HS_IND is active low,  
‘Asserted’ = the hub is connected at HS  
‘Negated’ = the hub is connected at FS  
CFG_SEL[1]  
CFG_SEL[2]  
Configuration Programming Select  
CFG_SEL[1]: The logic state of this pin is internally latched on the rising edge  
of RESET_N (RESET_N negation), and will determine the hub configuration  
method as described in Table 8.1, "Hub Configuration Options".  
I
Configuration Programming Select  
The logic state of this pin is internally latched on the rising edge of RESET_N  
(RESET_N negation), and will determine the hub configuration method as  
described in Table 8.1, "Hub Configuration Options". When the CFG_SEL[2]  
pin is unavailable, then the logic is internally tied to ‘0’.  
SMSC USB251x  
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Table 5.2 USB251x Pin Descriptions (continued)  
BUFFER  
SYMBOL  
TYPE  
DESCRIPTION  
MISC  
XTALIN  
ICLKx  
Crystal Input  
24 MHz crystal  
This pin connects to either one terminal of the crystal or to an external  
24 MHz clock when a crystal is not used.  
CLKIN  
External Clock Input  
This pin connects to either one terminal of the crystal or to an external  
24 MHz clock when a crystal is not used.  
XTALOUT  
OCLKx  
Crystal Output  
24 MHz crystal  
This is the other terminal of the crystal, or a no connect pin, when an external  
clock source is used to drive XTALIN/CLKIN.  
SUSP_IND /  
I/O  
Active/Suspend status LED  
Suspend Indicator: Indicates USB state of the hub.  
‘negated’ = Unconfigured, or configured and in USB Suspend  
‘asserted’ = the hub is configured, and is active (i.e., not in suspend)  
Local Power: Detects availability of local self-power source.  
LOCAL_PWR /  
NON_REM[0]  
Low = Self/local power source is NOT available (i.e., the hub gets all power  
from Upstream USB VBus).  
High = Self/local power source is available.  
NON_REM[0] Strap Option:  
If this strap is enabled by package and configuration settings (see Table 8.1,  
"Hub Configuration Options"), this pin will be sampled (in conjunction with  
NON_REM[1]) at RESET_N negation to determine if ports [x:1] contain  
permanently attached (non-removable) devices. Also, the active state of the  
LED will be determined as follows:  
NON_REM[1:0] = ‘00’, All ports are removable, and the LED is active high  
NON_REM[1:0] = ‘01’, Port 1 is non-removable, and the LED is active low  
NON_REM[1:0] = ‘10’, Ports 1 & 2 are non-removable, and the LED is active  
high  
NON_REM[1:0] = ‘11’, When available, ports 1, 2 & 3 are non-removable, and  
the LED is active low  
TEST  
IPD  
TEST pin  
User must treat as a no connect pin or connect to ground. No trace or signal  
should be routed or attached to this pin.  
Revision 1.1 (04-26-10)  
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Datasheet  
Table 5.2 USB251x Pin Descriptions (continued)  
BUFFER  
TYPE  
SYMBOL  
DESCRIPTION  
SEL48  
I
48 MHz Clock Input Selection  
48 MHz external input clock select. When the hub is clocked from an external  
clock source, this pin selects either 24 MHz or 48 MHz mode.  
‘0’ = 24 MHz  
‘1’ = 48 MHz  
POWER, GROUND, and NO CONNECTS  
CRFILT  
VDD Core Regulator Filter Capacitor  
This pin must have a 1.0 μF (or greater) ±20% (ESR <0.1 Ω) capacitor to  
VSS.  
VDD33  
3.3 V Power  
PLLFILT  
PLL Regulator Filter Capacitor  
This pin must have a 1.0 μF (or greater) ±20% (ESR <0.1 Ω) capacitor to  
VSS.  
VSS  
NC  
Ground Pad / ePad  
The package slug is the only VSS for the device and must be tied to ground  
with multiple vias.  
No Connect  
No signal or trace should be routed or attached to these pins.  
5.3  
Buffer Type Descriptions  
Table 5.3 Buffer Type Descriptions  
DESCRIPTION  
BUFFER  
I
Input.  
Input/Output.  
I/O  
IPD  
IPU  
IS  
Input with internal weak pull-down resistor.  
Input with internal weak pull-up resistor.  
Input with Schmitt trigger.  
O12  
Output 12 mA.  
SMSC USB251x  
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Datasheet  
Table 5.3 Buffer Type Descriptions (continued)  
BUFFER  
DESCRIPTION  
I/O12  
Input/Output buffer with 12 mA sink and 12 mA source.  
I/OSD12  
Open drain with Schmitt trigger and 12 mA sink. Meets the I2C-Bus specification,  
version 2.1, requirements.  
ICLKx  
OCLKx  
I-R  
XTAL clock input.  
XTAL clock output.  
RBIAS.  
I/O-U  
Analog Input/Output defined in USB specification.  
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Chapter 6 LED Usage Description  
6.1  
LED Functionality  
USB2513 and USB2514 (48-pin QFN only) and USB2517/17i SMSC hubs support two different  
(mutually exclusive) LED modes. The ‘x’ represents the number of downstream ports. The USB mode  
provides up to 14 LED’s that conform to the USB 2.0 specification functional requirements for Green  
and Amber LED’s. The LED mode “speed indicator” provides the downstream device connection  
speed.  
6.1.1  
USB Mode 14-Wire  
The LED_A_N[x:1] pins are used to provide Green LED support as defined in the USB 2.0  
specification. The LED_B_N[x:1] pins are used to provide Amber LED support as defined in the USB  
2.0 specification. The USB specification defines the LED’s as port status indicators for the downstream  
ports. Please note that no indication of port speed is possible in this mode. The pins are utilized as  
follows:  
LED_A_N[x:1] = Port [x:1] green LED  
LED_B_N[x:1] = Port [x:1] amber LED  
6.1.2  
LED Mode Speed Indication  
The LED_A[x:1]_N pins are used to provide connection status as well as port speed by using dual  
color LED's. This scheme requires that the LED's be in the same package, and that a third color is  
produced so that the user perceives both LED's as being driven "simultaneously".  
The LED_A[x:1] pins used in this mode are connected to x number of dual color LED’s (each LED pair  
in a single package). These pins indicate the USB speed of each attached downstream device.  
Each dual color LED provides two separate colors (commonly Green and Red). If each of these  
separate colors are pulsed on and off at a rapid rate, a user will see a third color (in this example,  
Orange). Using this method, 4 different "color" states are possible (Green, Red, Orange, and Off).  
3.3 V  
General  
Purpose  
Diode  
Connection to  
other Dual Color  
Diodes  
D1A (Green LED)  
Hub LED pin  
Current Limiting  
Resistor  
D1B (Red LED)  
Figure 6.1 Dual Color LED Implementation Example  
SMSC USB251x  
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Figure 6.1 shows a simple example of how this LED circuit will be implemented. The circuit should be  
replicated for each of the x LED pins on the SMSC hub. In this circuit, when the LED pin is driven to  
a logic low state, the Green LED will light up. When the LED pin is driven to a Logic High state the  
Red LED will light up. When a 1 KHz square wave is driven out on the LED pin, the Green and Red  
LED's will both alternately light up giving the effect of the color Orange. When nothing is driven out on  
the LED pin (i.e. the pin floats to a "tri-state" condition), neither the Green nor Red LED will light up,  
this is the "Off" state.  
The assignment is as follows:  
LED_A_N[x:1] = LED D[x:1] (Downstream Port [x:1])  
The usage is as follows:  
LED_A_N[x] Driven to Logic Low = LS device attached (Green LED)  
LED_A_N[x] Driven to Logic High = FS device attached (Red LED)  
LED_A_N[x] Pulsed @ 1 KHz = HS device attached (Orange color by pulsing Red & Green).  
LED_A_N[x] is tri-state= No devices are attached, or the hub is in suspend, LED's are off.  
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Chapter 7 Battery Charging Support  
7.1  
General Description  
The battery charging feature is only available in USB251xB (which represents USB2512B/3B/4B and  
USB2512Bi/3Bi/4Bi hub family products). Any one or combination of downstream ports on the  
USB251xB hub can be configured to support battery charging.  
The SMSC hub provides support for battery charging devices on a per port basis in compliance with  
the USB Battery Charging specification, version 1.1. The hub can be configured to individually enable  
each downstream port for battery charging support either via pin strapping as illustrated in Figure 7.1  
or by setting the corresponding configuration bits via EEPROM or SMBus.  
3.3 V  
5 V  
USB Port Power  
Controller  
RSTRAP  
IN  
PRTPWR[x]  
OCS_N[x]  
VBUS  
USB251xB/xBi  
EN  
FLAG  
Note: RSTRAP enables battery charging.  
Figure 7.1 Battery Charging via External Power Supply  
7.2  
USB Battery Charging  
A downstream port enabled for battery charging turns on port power as soon as the configuration  
process has completed. The hub does not need to be enumerated nor does VBUS_DET need to be  
asserted for the port power to be enabled. These conditions allow battery charging in S3, S4 and S5  
system power states as well as in the fully operational state. The USB Battery Charging specification  
does not interfere with standard USB operation, which allows a device to perform battery charging at  
any time.  
A port that supports battery charging must be able to support 1.5 amps of current on VBUS. Standard  
USB port power controllers typically only allow for 0.8 amps of current before detecting an over-current  
condition. Therefore, the 5 volt power supply, port power controller or over-current protection devices  
must be chosen to handle the larger current demand compared to standard USB hub designs.  
7.2.1  
Special Behavior of PRTPWR Pins  
The SMSC hub enables VBUS by asserting the port power (PRTPWR) pin as soon as the hardware  
configuration process has completed. If the port detects an over-current condition, PRTPWR will be  
turned off to protect the circuitry from overloading. If an over-current condition is detected when the  
hub is not enumerated, PRTPWR can only be turned on from the host or if RESET_N is toggled. These  
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behaviors provide battery charging even when the hub is not enumerated and protect the hub from  
sustained short circuit conditions. If the short circuit condition persists when the hub is plugged into a  
host system the user is notified that a port has an over-current condition. Otherwise the PRTPWR is  
turned on by the host system and the port operates normally.  
7.3  
Battery Charging Configuration  
Configuration of ports to support battery charging is done through a strap option on the corresponding  
ports PRTPWR[x] / BC_EN[x] pin. see Chapter 5, Pin Descriptions, or through EEPROM or SMBus  
configuration load.  
7.3.1  
Battery Charging enabled via EEPROM or SMBus  
Register memory map location 0xD0 is allocated for battery charging support. The "Battery Charging"  
register at location 0xD0 starting from Bit 1 enables battery charging for each downstream port when  
asserted. Bit 1 represents port 1 and so on. Each port with battery charging enabled asserts the  
corresponding PRTPWR[x:0] pin.  
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Chapter 8 Configuration Options  
8.1  
Hub  
SMSC’s USB 2.0 hub is fully specification compliant to the Universal Serial Bus specification, version  
2.0, April 27, 2000 (12/7/2000 and 5/28/2002 Errata). Please reference Chapter 10 (Hub specification)  
for general details regarding hub operation and functionality.  
The hub provides 1 Transaction Translator (TT) that is shared by both downstream ports (defined as  
Single-TT configuration), The TT contains 4 non-periodic buffers.  
8.1.1  
Hub Configuration Options  
The SMSC hub supports a large number of features (some are mutually exclusive), and must be  
configured in order to correctly function when attached to a USB host controller. There are three  
principal ways to configure the hub: SMBus, EEPROM, or by internal default settings (with or without  
configuration option over-rides). In all cases, the configuration method will be determined by the  
CFG_SEL[2], CFG_SEL[1] and CFG_SEL[0] pins immediately after RESET_N negation. Please refer  
to Table 8.1, "Hub Configuration Options" for more information.  
8.1.2  
SMBus or EEPROM Interface  
Table 8.1 Hub Configuration Options  
CFG_SEL[2]  
CFG_SEL[1]  
CFG_SEL[0]  
DESCRIPTION  
0
0
0
Internal Default Configuration without any over-rides  
„
„
„
„
„
Strap options enabled  
Self-powered operation enabled  
LED mode = Speed (when available on package)  
Individual power switching  
Individual over-current sensing  
0
0
0
1
1
0
Configured as an SMBus slave for external download of  
user-defined descriptors  
„
Strap options disabled  
„
All settings are controlled by registers as set by the user  
Internal Default Configuration  
„
„
„
„
„
Strap options enabled  
Bus-powered operation  
LED mode = USB (when available on package)  
Individual power switching  
Individual over-current sensing  
0
1
1
2-Wire I2C EEPROMS are supported  
„
Strap options disabled  
„
All settings are controlled by registers as set by the user  
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Table 8.1 Hub Configuration Options (continued)  
CFG_SEL[2]  
CFG_SEL[1]  
CFG_SEL[0]  
DESCRIPTION  
1
0
0
Internal Default Configuration with the following over-rides  
„
„
„
„
„
Dynamic power-switching enabled  
Strap options disabled  
LED mode = Speed (when available on package)  
Individual power switching  
Individual over-current sensing  
1
0
1
Internal Default Configuration with the following over-rides  
„
„
„
„
„
Dynamic power-switching enabled  
Strap options disabled  
LED mode = USB (when available on package)  
Individual power switching  
Individual over-current sensing  
1
1
1
1
0
1
Internal Default Configuration with the following over-rides  
„
„
„
„
Strap options disabled  
LED mode = Speed (when available on package)  
Individual power switching  
Individual over-current sensing  
Internal Default Configuration with the following over-rides  
„ Strap options disabled  
„ LED mode = USB (when available on package)  
„ Ganged port power switching  
„ Ganged over-current sensing  
Note: When the CFG_SEL[2] pin is unavailable, then the logic is internally tied to ‘0’.  
8.1.2.1  
Power Switching Polarity  
When the PRTPWR_POL pin is unavailable (3 and 4 port, 48-pin packages only), the hub only  
supports “active high” port power controllers.  
8.1.3  
VBus Detect  
According to Section 7.2.1 of the USB 2.0 specification, a downstream port can never provide power  
to its D+ or D- pull-up resistors unless the upstream port’s VBUS is in the asserted (powered) state.  
The VBUS_DET pin on the hub monitors the state of the upstream VBUS signal and will not pull-up  
the D+ resistor if VBUS is not active. If VBUS goes from an active to an inactive state (Not Powered),  
the hub will remove power from the D+ pull-up resistor within 10 seconds.  
8.2  
EEPROM Interface  
The SMSC hub can be configured via a 2-wire (I2C) EEPROM (256x8). (Please see Table 8.1, "Hub  
Configuration Options" for specific details on how to enable configuration via an I2C EEPROM).  
The internal state-machine will (when configured for EEPROM support) read the external EEPROM for  
configuration data. The hub will then “attach” to the upstream USB host.  
Note: The hub does not have the capacity to write, or “Program,” an external EEPROM. The hub  
only has the capability to read external EEPROMs. The external eeprom will be read (even if  
it is blank or non-populated), and the hub will be “configured” with the values that are read.  
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Please see the Internal Register Set (Common to EEPROM and SMBus) for a list of the available data  
fields. Please visit www.smsc.com/ftpdocs/usb.html to locate the configuration utility for the hub  
EEPROM data. Select the “e2prommap.msi” link to download the tool.  
Each register has R/W capability. SMBUS and EEPROM Reset Values are 0x00. Reserved registers  
should be written to ‘0’ unless otherwise specified. Contents read should be ignored (such as the case  
of ‘R’ in the table below).  
8.2.1  
Internal Register Set (Common to EEPROM and SMBus)  
Table 8.2 Internal Default, EEPROM and SMBus Register Memory Map  
DEFAULT ROM VALUES (HEXIDECIMAL)  
ADDRESS  
REGISTER NAME  
00h  
01h  
02h  
03h  
04h  
05h  
06h  
07h  
08h  
09h  
0Ah  
0Bh  
0Ch  
0Dh  
0Eh  
0Fh  
10h  
11h  
Vendor ID LSB  
Vendor ID MSB  
24  
04  
Product ID LSB  
12  
13  
14  
12  
13  
14  
17  
Product ID MSB  
25  
Device ID LSB  
00 A0  
00 0A  
8B  
00  
00  
A0  
0B  
00  
00  
Device ID MSB  
Configuration Data Byte 1  
Configuration Data Byte 2  
Configuration Data Byte 3  
Non-Removable Devices  
Port Disable (Self)  
9B  
20  
02  
00  
08  
08  
00  
00  
Port Disable (Bus)  
Max Power (Self)  
01  
32  
01  
32  
32  
00  
Max Power (Bus)  
Hub Controller Max Current (Self)  
Hub Controller Max Current (Bus)  
Power-on Time  
Language ID High  
12h  
13h  
14h  
15h  
16h-53h  
Language ID Low  
R
R
R
R
R
00  
00  
00  
00  
00  
Manufacturer String Length  
Product String Length  
Serial String Length  
Manufacturer String  
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Table 8.2 Internal Default, EEPROM and SMBus Register Memory Map (continued)  
DEFAULT ROM VALUES (HEXIDECIMAL)  
ADDRESS  
REGISTER NAME  
54h-91h  
92h-CFh  
D0h  
Product String  
Serial String  
Battery Charging Enable  
Reserved  
R
R
00  
00  
R
00  
E0h  
00  
R
F5h  
Reserved  
00  
00  
R
R
00  
F6h  
Boost_Up  
00  
F7h  
Boost_7:5  
00  
F8h  
Boost_x:0  
00  
00  
00  
00  
F9h  
Reserved  
FAh  
Port Swap  
FBh  
Port Map 12  
Port Map 34  
Port Map 56  
Port Map 7  
FCh  
FDh  
FEh  
R
00  
R
00  
R
R
00  
00  
FFh  
Status/Command  
Note: SMBus register only  
00  
8.2.1.1  
Register 00h: Vendor ID (LSB)  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
VID_LSB  
Least Significant Byte of the Vendor ID. This is a 16-bit value that uniquely  
identifies the Vendor of the user device (assigned by USB-Interface Forum).  
This field is set by the OEM using either the SMBus or EEPROM interface  
options.  
8.2.1.2  
Register 01h: Vendor ID (MSB)  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
VID_MSB  
Most Significant Byte of the Vendor ID. This is a 16-bit value that uniquely  
identifies the Vendor of the user device (assigned by USB-Interface Forum).  
This field is set by the OEM using either the SMBus or EEPROM interface  
options.  
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8.2.1.3  
Register 02h: Product ID (LSB)  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
PID_LSB  
Least Significant Byte of the Product ID. This is a 16-bit value that the Vendor  
can assign that uniquely identifies this particular product (assigned by OEM).  
This field is set by the OEM using either the SMBus or EEPROM interface  
options.  
8.2.1.4  
Register 03h: Product ID (MSB)  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
PID_MSB  
Most Significant Byte of the Product ID. This is a 16-bit value that the Vendor  
can assign that uniquely identifies this particular product (assigned by OEM).  
This field is set by the OEM using either the SMBus or EEPROM interface  
options.  
8.2.1.5  
Register 04h: Device ID (LSB)  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
DID_LSB  
Least Significant Byte of the Device ID. This is a 16-bit device release  
number in BCD format (assigned by OEM). This field is set by the OEM  
using either the SMBus or EEPROM interface options.  
8.2.1.6  
Register 05h: Device ID (MSB)  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
DID_MSB  
Most Significant Byte of the Device ID. This is a 16-bit device release  
number in BCD format (assigned by OEM). This field is set by the OEM  
using either the SMBus or EEPROM interface options.  
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8.2.1.7  
Register 06h: CONFIG_BYTE_1  
BIT NAME  
BIT  
NUMBER  
DESCRIPTION  
7
SELF_BUS_PWR  
Self or Bus Power: Selects between Self- and Bus-Powered operation.  
The hub is either self-powered (draws less than 2 mA of upstream bus  
power) or bus-powered (limited to a 100 mA maximum of upstream power  
prior to being configured by the host controller).  
When configured as a bus-powered device, the SMSC hub consumes less  
than 100 mA of current prior to being configured. After configuration, the bus-  
powered SMSC hub (along with all associated hub circuitry, any embedded  
devices if part of a compound device, and 100 mA per externally available  
downstream port) must consume no more than 500 mA of upstream VBUS  
current. The current consumption is system dependent, and the OEM must  
ensure that the USB 2.0 specifications are not violated.  
When configured as a self-powered device, <1 mA of upstream VBUS  
current is consumed and all ports are available, with each port being capable  
of sourcing 500 mA of current.  
This field is set by the OEM using either the SMBus or EEPROM interface  
options.  
Please see the description under dynamic power for the self-/bus- power  
functionality when dynamic power switching is enabled.  
'0' = Bus-powered operation  
’1’ = Self-powered operation  
If dynamic power switching is enabled, this bit is ignored and the  
LOCAL_PWR pin is used to determine if the hub is operating from self or  
bus power.  
6
5
Reserved  
Reserved  
HS_DISABLE  
Hi-speed Disable: Disables the capability to attach as either a Hi-/Full-Speed  
device, and forces attachment as Full-Speed only (i.e. no Hi-Speed support).  
'0' = Hi-/Full-speed  
‘1’ = Full-speed-Only (Hi-speed disabled!)  
4
MTT_ENABLE  
Multi-TT enable: Enables one transaction translator per port operation.  
(Not available on the USB2512A/12Ai.)  
Selects between a mode where only one transaction translator is available  
for all ports (Single-TT), or each port gets a dedicated transaction translator  
(Multi-TT).  
'0' = Single TT for all ports  
‘1’ = One TT per port (when multiple TT's are supported)  
3
EOP_DISABLE  
EOP Disable: Disables EOP generation at EOF1 when in Full-Speed mode.  
During FS operation only, this permits the hub to send EOP if no  
downstream traffic is detected at EOF1. See Section 11.3.1 of the USB 2.0  
specification for additional details.  
'0' = EOP generation is normal  
‘1’ = EOP generation is disabled  
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BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
2:1  
CURRENT_SNS  
Over-Current Sense: Selects current sensing on a port-by-port basis, all  
ports ganged, or none (only for bus-powered hubs). The ability to support  
current sensing on a port or ganged basis is hardware implementation  
dependent.  
‘00’ = Ganged sensing (all ports together)  
‘01’ = Individual (port-by-port)  
‘1x’ = Over-current sensing not supported (must only be used with bus-  
powered configurations!)  
0
PORT_PWR  
Port Power Switching: Enables power switching on all ports simultaneously  
(ganged), or port power is individually switched on and off on a port- by-port  
basis (individual). The ability to support power enabling on a port or ganged  
basis is hardware implementation dependent.  
‘0’ = Ganged switching (all ports together)  
‘1’ = Individual port-by-port switching  
8.2.1.8  
Register 07h: Configuration Data Byte 2  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7
DYNAMIC  
Dynamic Power Enable: Controls the ability of the hub to automatically  
change from self-powered operation to bus-powered operation if the local  
power source is removed or is unavailable (and from bus-powered to self-  
powered if the local power source is restored).  
When dynamic power switching is enabled, the hub detects the availability  
of a local power source by monitoring the external LOCAL_PWR pin. If the  
hub detects a change in power source availability, the hub immediately  
disconnects and removes power from all downstream devices and  
disconnects the upstream port. The hub will then re-attach to the upstream  
port as either a bus-powered hub (if local-power is unavailable) or a self-  
powered hub (if local power is available).  
‘0’ = No dynamic auto-switching  
‘1’ = Dynamic auto-switching capable  
6
Reserved  
Reserved  
5:4  
OC_TIMER  
OverCurrent Timer: Over-current Timer delay.  
‘00’ = 0.1 ms  
‘01’ = 4.0 ms  
‘10’ = 8.0 ms  
‘11’ = 16.0 ms  
3
COMPOUND  
Compound Device: Allows OEM to indicate that the hub is part of a  
compound (see the USB specification for definition) device. The applicable  
port(s) must also be defined as having a "Non-Removable Device".  
Note:  
When configured via strapping options, declaring a port as non-  
removable automatically causes the hub controller to report that it  
is part of a compound device.  
‘0’ = No  
‘1’ = Yes, The hub is part of a compound device  
2:0  
Reserved  
Reserved  
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8.2.1.9  
Register 08h: Configuration Data Byte 3  
BIT NAME  
BIT  
NUMBER  
DESCRIPTION  
7:4  
3
Reserved  
Reserved  
PRTMAP_EN  
Port mapping enable: Selects the method used by the hub to assign port  
numbers and disable ports.  
‘0’ = Standard mode  
‘1’ = Port mapping mode  
2:1  
LED_MODE  
LED Mode Selection: The LED_A[x:1]_N and LED_B[x:1]_N pins support  
several different modes of operation (depending upon OEM implementation  
of the LED circuit).  
‘00' = USB Mode  
‘01’ = Speed Indication Mode  
‘10’ = Same as ‘00’, USB Mode  
‘11’ = Same as ‘00’, USB Mode  
Warning: Do not enable an LED mode that requires LED pins that are not  
available in the specific package being used in the implementation.  
Note:  
The hub will only report that it supports LED's to the host when  
USB mode is selected. All other modes will be reported as No LED  
Support.  
0
STRING_EN  
Enables String Descriptor Support  
‘0’ = String support disabled  
‘1’ = String support enabled  
8.2.1.10  
Register 09h: Non-Removable Device  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
NR_DEVICE  
Non-removable Device: Indicates which port(s) include non-removable  
devices.  
‘0’ = port is removable  
‘1’ = port is non-removable  
Informs the host if one of the active ports has a permanent device that is  
undetachable from the hub. (Note: The device must provide its own  
descriptor data.)  
When using the internal default option, the NON_REM[1:0] pins will  
designate the appropriate ports as being non- removable.  
Bit 7= Controls Port 7  
Bit 6= Controls Port 6  
Bit 5= Controls Port 5  
Bit 4= Controls Port 4  
Bit 3= Controls Port 3  
Bit 2= Controls Port 2  
Bit 1= Controls Port 1  
Bit 0= Reserved  
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8.2.1.11  
Register 0Ah: Port Disable For Self-Powered Operation  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
PORT_DIS_SP  
Port Disable Self-Powered: Disables 1 or more ports.  
0 = Port is available  
1 = Port is disabled  
During self-powered operation when mapping mode is disabled  
(PRTMAP_EN='0'), this selects the ports which will be permanently disabled,  
and are not available to be enabled or enumerated by a host controller. The  
ports can be disabled in any order, the internal logic will automatically report  
the correct number of enabled ports to the USB host, and will reorder the  
active ports in order to ensure proper function.  
When using the internal default option, the PRT_DIS_P[x:1] and  
PRT_DIS_M[x:1] pins will disable the appropriate ports.  
Bit 7= Controls Port 7  
Bit 6= Controls Port 6  
Bit 5= Controls Port 5  
Bit 4= Controls Port 4  
Bit 3= Controls Port 3  
Bit 2= Controls Port 2  
Bit 1= Controls Port 1  
Bit 0= Reserved, always = ‘0’  
8.2.1.12  
Register 0Bh: Port Disable For Bus-Powered Operation  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
PORT_DIS_BP  
Port Disable Bus-Powered: Disables 1 or more ports.  
0 = Port is available  
1 = Port is disabled  
During self-powered operation when mapping mode is disabled  
(PRTMAP_EN='0'), this selects the ports which will be permanently disabled,  
and are not available to be enabled or enumerated by a host Controller. The  
ports can be disabled in any order, the internal logic will automatically report  
the correct number of enabled ports to the USB host, and will reorder the  
active ports in order to ensure proper function.  
When using the internal default option, the PRT_DIS_P[x:1] and  
PRT_DIS_M[x:1] pins will disable the appropriate ports.  
Bit 7= Controls Port 7  
Bit 6= Controls Port 6  
Bit 5= Controls Port 5  
Bit 4= Controls Port 4  
Bit 3= Controls Port 3  
Bit 2= Controls Port 2  
Bit 1= Controls Port 1  
Bit 0 is Reserved, always = ‘0’  
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8.2.1.13  
Register 0Ch: Max Power For Self-Powered Operation  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
MAX_PWR_SP  
Max Power Self_Powered: Value in 2 mA increments that the hub consumes  
from an upstream port (VBUS) when operating as a self-powered hub. This  
value includes the hub silicon along with the combined power consumption  
(from VBUS) of all associated circuitry on the board. This value also includes  
the power consumption of a permanently attached peripheral if the hub is  
configured as a compound device, and the embedded peripheral reports 0  
mA in its descriptors.  
Note:  
The USB 2.0 specification does not permit this value to exceed 100  
mA  
8.2.1.14  
Register 0Dh: Max Power For Bus-Powered Operation  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
MAX_PWR_BP  
Max Power Bus_Powered: Value in 2 mA increments that the hub consumes  
from an upstream port (VBUS) when operating as a bus-powered hub. This  
value includes the hub silicon along with the combined power consumption  
(from VBUS) of all associated circuitry on the board. This value also includes  
the power consumption of a permanently attached peripheral if the hub is  
configured as a compound device, and the embedded peripheral reports 0  
mA in its descriptors.  
8.2.1.15  
Register 0Eh: Hub Controller Max Current For Self-Powered Operation  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
HC_MAX_C_SP  
Hub Controller Max Current Self-Powered: Value in 2 mA increments that the  
hub consumes from an upstream port (VBUS) when operating as a self-  
powered hub. This value includes the hub silicon along with the combined  
power consumption (from VBUS) of all associated circuitry on the board.  
This value does NOT include the power consumption of a permanently  
attached peripheral if the hub is configured as a compound device.  
Note:  
The USB 2.0 specification does not permit this value to exceed 100  
mA  
A value of 50 (decimal) indicates 100 mA, which is the default value.  
8.2.1.16  
Register 0Fh: Hub Controller Max Current For Bus-Powered Operation  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
HC_MAX_C_BP  
Hub Controller Max Current Bus-Powered: Value in 2 mA increments that the  
hub consumes from an upstream port (VBUS) when operating as a bus-  
powered hub. This value will include the hub silicon along with the combined  
power consumption (from VBUS) of all associated circuitry on the board.  
This value will NOT include the power consumption of a permanently  
attached peripheral if the hub is configured as a compound device.  
A value of 50 (decimal) would indicate 100 mA, which is the default value.  
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8.2.1.17  
Register 10h: Power-On Time  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
POWER_ON_TIME  
Power-On Time: The length of time that it takes (in 2 ms intervals) from the  
time the host initiated power-on sequence begins on a port until power is  
adequate on that port.  
8.2.1.18  
Register 11h: Language ID High  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
LANG_ID_H  
USB Language ID (Upper 8 bits of a 16-bit ID field)  
8.2.1.19  
Register 12h: Language ID Low  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
LANG_ID_L  
USB Language ID (Lower 8 bits of a 16-bit ID field)  
8.2.1.20  
Register 13h: Manufacturer String Length  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
MFR_STR_LEN  
Manufacturer String Length  
When supported, the maximum string length is 31 characters.  
8.2.1.21  
Register 14h: Product String Length  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
PRD_STR_LEN  
Product String Length  
When supported, the maximum string length is 31 characters.  
8.2.1.22  
Register 15h: Serial String Length  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
SER_STR_LEN  
Serial String Length  
When supported, the maximum string length is 31 characters.  
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8.2.1.23  
Register 16h-53h: Manufacturer String  
BIT NAME  
BIT  
NUMBER  
DESCRIPTION  
7:0  
MFR_STR  
Manufacturer String, UNICODE UTF-16LE per USB 2.0 specification  
When supported, the maximum string length is 31 characters (62 bytes).  
Note:  
The string consists of individual 16-bit UNICODE UTF-16LE  
characters. The Characters will be stored starting with the LSB at  
the least significant address and the MSB at the next 8-bit location  
(subsequent characters must be stored in sequential contiguous  
address in the same LSB, MSB manner). Some EEPROM  
programmers may transpose the MSB and LSB, thus reversing the  
Byte order. Please pay careful attention to the Byte ordering or your  
selected programming tools.  
8.2.1.24  
Register 54h-91h: Product String  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
PRD_STR  
Product String, UNICODE UTF-16LE per USB 2.0 specification  
When supported, the maximum string length is 31 characters (62 bytes).  
Note:  
The string consists of individual 16-bit UNICODE UTF-16LE  
characters. The Characters will be stored starting with the LSB at  
the least significant address and the MSB at the next 8-bit location  
(subsequent characters must be stored in sequential contiguous  
address in the same LSB, MSB manner). Some EEPROM  
programmers may transpose the MSB and LSB, thus reversing the  
Byte order. Please pay careful attention to the Byte ordering or your  
selected programming tools.  
8.2.1.25  
Register 92h-CFh: Serial String  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
SER_STR  
Serial String, UNICODE UTF-16LE per USB 2.0 specification  
When supported, the maximum string length is 31 characters (62 bytes).  
Note:  
The string consists of individual 16-bit UNICODE UTF-16LE  
characters. The Characters will be stored starting with the LSB at  
the least significant address and the MSB at the next 8-bit location  
(subsequent characters must be stored in sequential contiguous  
address in the same LSB, MSB manner). Some EEPROM  
programmers may transpose the MSB and LSB, thus reversing the  
Byte order. Please pay careful attention to the Byte ordering or your  
selected programming tools.  
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8.2.1.26  
Register D0h: Battery Charging Enable  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
BC_EN  
Only available in USB251xB/Bi hub family products.  
Battery Charging Enable: Enables the battery charging feature for the  
corresponding port.  
'0' = Battery Charging support is not enabled  
'1' = Battery charging support is enabled  
Bit 7= Reserved  
Bit 6= Reserved  
Bit 5= Reserved  
Bit 4= Controls Port 4  
Bit 3= Controls Port 3  
Bit 2= Controls Port 2  
Bit 1= Controls Port 1  
Bit 0= Reserved  
8.2.1.27  
Register F6h: Boost_Up  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:2  
1:0  
Reserved  
Reserved  
BOOST_IOUT  
USB electrical signaling drive strength Boost Bit for the Upstream Port.  
‘00’ = Normal electrical drive strength = No boost  
‘01’ = Elevated electrical drive strength = Low (~ 4% boost)  
‘10’ = Elevated electrical drive strength = Medium (~ 8% boost)  
‘11’ = Elevated electrical drive strength = High (~12% boost)  
Note:  
“Boost” could result in non-USB Compliant parameters, OEM  
should use a ‘00’ value unless specific implementation issues  
require additional signal boosting to correct for degraded USB  
signalling levels.  
8.2.1.28  
Register F7h: Boost_7:5  
BIT NAME  
BIT  
NUMBER  
DESCRIPTION  
7:6  
5:4  
Reserved  
Reserved  
BOOST_IOUT_7  
USB electrical signaling drive strength Boost Bit for Downstream Port ‘7’.  
‘00’ = Normal electrical drive strength = No boost  
‘01’ = Elevated electrical drive strength = Low (~4% boost)  
‘10’ = Elevated electrical drive strength = Medium (~ 8% boost)  
‘11’ = Elevated electrical drive strength = High (~12% boost)  
3:2  
BOOST_IOUT_6  
USB electrical signaling drive strength Boost Bit for Downstream Port ‘6’.  
‘00’ = Normal electrical drive strength = No boost  
‘01’ = Elevated electrical drive strength = Low (~4% boost)  
‘10’ = Elevated electrical drive strength = Medium (~ 8% boost)  
‘11’ = Elevated electrical drive strength = High (~12% boost)  
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BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
1:0  
BOOST_IOUT_5  
USB electrical signaling drive strength Boost Bit for Downstream Port ‘5’.  
‘00’ = Normal electrical drive strength = No boost  
‘01’ = Elevated electrical drive strength = Low (~4% boost)  
‘10’ = Elevated electrical drive strength = Medium (~ 8% boost)  
‘11’ = Elevated electrical drive strength = High (~12% boost)  
Note: “Boost” could result in non-USB Compliant parameters, OEM should use a ‘00’ value unless  
specific implementation issues require additional signal boosting to correct for degraded USB  
signalling levels.  
8.2.1.29  
Register F8h: Boost_4:0  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:6  
5:4  
3:2  
1:0  
BOOST_IOUT_4  
USB electrical signaling drive strength Boost Bit for Downstream Port ‘4’.  
‘00’ = Normal electrical drive strength = No boost  
‘01’ = Elevated electrical drive strength = Low (~4% boost)  
‘10’ = Elevated electrical drive strength = Medium (~ 8% boost)  
‘11’ = Elevated electrical drive strength = High (~12% boost)  
BOOST_IOUT_3  
BOOST_IOUT_2  
BOOST_IOUT_1  
USB electrical signaling drive strength Boost Bit for Downstream Port ‘3’.  
‘00’ = Normal electrical drive strength = No boost  
‘01’ = Elevated electrical drive strength = Low (~4% boost)  
‘10’ = Elevated electrical drive strength = Medium (~ 8% boost)  
‘11’ = Elevated electrical drive strength = High (~12% boost)  
USB electrical signaling drive strength Boost Bit for Downstream Port ‘2’.  
‘00’ = Normal electrical drive strength = No boost  
‘01’ = Elevated electrical drive strength = Low (~4% boost)  
‘10’ = Elevated electrical drive strength = Medium (~ 8% boost)  
‘11’ = Elevated electrical drive strength = High (~12% boost)  
USB electrical signaling drive strength Boost Bit for Downstream Port ‘1’.  
‘00’ = Normal electrical drive strength = No boost  
‘01’ = Elevated electrical drive strength = Low (~4% boost)  
‘10’ = Elevated electrical drive strength = Medium (~ 8% boost)  
‘11’ = Elevated electrical drive strength = High (~12% boost)  
Note: “Boost” could result in non-USB Compliant parameters, OEM should use a ‘00’ value unless  
specific implementation issues require additional signal boosting to correct for degraded USB  
signalling levels.  
Revision 1.1 (04-26-10)  
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USB 2.0 Hi-Speed Hub Controller  
Datasheet  
8.2.1.30  
Register FAh: Port Swap  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
PRTSP  
Port Swap: Swaps the Upstream and Downstream USB DP and DM Pins for  
ease of board routing to devices and connectors.  
‘0’ = USB D+ functionality is associated with the DP pin and D- functionality  
is associated with the DM pin.  
‘1’ = USB D+ functionality is associated with the DM pin and D- functionality  
is associated with the DP pin.  
Bit 7= Controls Port 7  
Bit 6= Controls Port 6  
Bit 5= Controls Port 5  
Bit 4= Controls Port 4  
Bit 3= Controls Port 3  
Bit 2= Controls Port 2  
Bit 1= Controls Port 1  
Bit 0= When this bit is ‘1’, the upstream port DP/DM is swapped.  
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Datasheet  
8.2.1.31  
Register FBh: PortMap 12  
BIT NAME  
BIT  
NUMBER  
DESCRIPTION  
PortMap register for ports 1 & 2.  
7:0  
PRTR12  
When a hub is enumerated by a USB host controller, the hub is only  
permitted to report how many ports it has; the hub is not permitted to select  
a numerical range or assignment. The host controller will number the  
downstream ports of the hub starting with the number '1', up to the number  
of ports that the hub reported having.  
The host's port number is referred to as "Logical Port Number" and the  
physical port on the hub is the “Physical Port Number". When mapping mode  
is enabled (see PRTMAP_EN in Register 08h: Configuration Data Byte 3)  
the hub's downstream port numbers can be mapped to different logical port  
numbers (assigned by the host).  
Note:  
OEM must ensure that contiguous logical port numbers are used,  
starting from #1 up to the maximum number of enabled ports; this  
ensures that the hub's ports are numbered in accordance with the  
way a host will communicate with the ports.  
Table 8.3 PortMap Register for Ports 1 & 2  
Bit [7:4]  
‘0000’  
‘0001’  
‘0010’  
‘0011’  
‘0100’  
‘0101’  
‘0100’  
‘0111’  
Physical Port 2 is Disabled  
Physical Port 2 is mapped to Logical Port 1  
Physical Port 2 is mapped to Logical Port 2  
Physical Port 2 is mapped to Logical Port 3  
Physical Port 2 is mapped to Logical Port 4  
Physical Port 2 is mapped to Logical Port 5  
Physical Port 2 is mapped to Logical Port 6  
Physical Port 2 is mapped to Logical Port 7  
Reserved, will default to ‘0000’ value  
‘1000’  
to  
‘1111’  
Bit [3:0]  
‘0000’  
‘0001’  
‘0010’  
‘0011’  
‘0100’  
‘0101’  
‘0110’  
‘0111’  
Physical Port 1 is Disabled  
Physical Port 1 is mapped to Logical Port 1  
Physical Port 1 is mapped to Logical Port 2  
Physical Port 1 is mapped to Logical Port 3  
Physical Port 1 is mapped to Logical Port 4  
Physical Port 1 is mapped to Logical Port 5  
Physical Port 1 is mapped to Logical Port 6  
Physical Port 1 is mapped to Logical Port 7  
Reserved, will default to ‘0000’ value  
‘1000’  
to  
‘1111’  
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8.2.1.32  
Register FCh: PortMap 34  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
PortMap register for ports 3 & 4.  
7:0  
PRTR34  
When a hub is enumerated by a USB host controller, the hub is only  
permitted to report how many ports it has; the hub is not permitted to select  
a numerical range or assignment. The host controller will number the  
downstream ports of the hub starting with the number '1', up to the number  
of ports that the hub reported having.  
The host's port number is referred to as "Logical Port Number" and the  
physical port on the hub is the “Physical Port Number". When mapping mode  
is enabled (see PRTMAP_EN in Register 08h: Configuration Data Byte 3)  
the hub's downstream port numbers can be mapped to different logical port  
numbers (assigned by the host).  
Note:  
OEM must ensure that contiguous logical port numbers are used,  
starting from #1 up to the maximum number of enabled ports; this  
ensures that the hub's ports are numbered in accordance with the  
way a host will communicate with the ports.  
Table 8.4 PortMap Register for Ports 3 & 4  
Bit [7:4]  
‘0000’  
‘0001’  
‘0010’  
‘0011’  
‘0100’  
‘0101’  
‘0100’  
‘0111’  
Physical Port 4 is Disabled  
Physical Port 4 is mapped to Logical Port 1  
Physical Port 4 is mapped to Logical Port 2  
Physical Port 4 is mapped to Logical Port 3  
Physical Port 4 is mapped to Logical Port 4  
Physical Port 4 is mapped to Logical Port 5  
Physical Port 4 is mapped to Logical Port 6  
Physical Port 4 is mapped to Logical Port 7  
Reserved, will default to ‘0000’ value  
‘1000’  
to  
‘1111’  
Bit [3:0]  
‘0000’  
‘0001’  
‘0010’  
‘0011’  
‘0100’  
‘0101’  
‘0110’  
‘0111’  
Physical Port 3 is Disabled  
Physical Port 3 is mapped to Logical Port 1  
Physical Port 3 is mapped to Logical Port 2  
Physical Port 3 is mapped to Logical Port 3  
Physical Port 3 is mapped to Logical Port 4  
Physical Port 3 is mapped to Logical Port 5  
Physical Port 3 is mapped to Logical Port 6  
Physical Port 3 is mapped to Logical Port 7  
Reserved, will default to ‘0000’ value  
‘1000’  
to  
‘1111’  
SMSC USB251x  
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Datasheet  
8.2.1.33  
Register FDh: PortMap 56  
BIT NAME  
BIT  
NUMBER  
DESCRIPTION  
PortMap register for ports 5 & 6.  
7:0  
PRTR56  
When a hub is enumerated by a USB host controller, the hub is only  
permitted to report how many ports it has; the hub is not permitted to select  
a numerical range or assignment. The host controller will number the  
downstream ports of the hub starting with the number '1', up to the number  
of ports that the hub reported having.  
The host's port number is referred to as "Logical Port Number" and the  
physical port on the hub is the “Physical Port Number". When mapping mode  
is enabled (see PRTMAP_EN in Register 08h: Configuration Data Byte 3)  
the hub's downstream port numbers can be mapped to different logical port  
numbers (assigned by the host).  
Note:  
OEM must ensure that contiguous logical port numbers are used,  
starting from #1 up to the maximum number of enabled ports; this  
ensures that the hub's ports are numbered in accordance with the  
way a host will communicate with the ports.  
Table 8.5 PortMap Register for Ports 5 & 6  
Bit [7:4]  
‘0000’  
‘0001’  
‘0010’  
‘0011’  
‘0100’  
‘0101’  
‘0100’  
‘0111’  
Physical Port 6 is Disabled  
Physical Port 6 is mapped to Logical Port 1  
Physical Port 6 is mapped to Logical Port 2  
Physical Port 6 is mapped to Logical Port 3  
Physical Port 6 is mapped to Logical Port 4  
Physical Port 6 is mapped to Logical Port 5  
Physical Port 6 is mapped to Logical Port 6  
Physical Port 6 is mapped to Logical Port 7  
Reserved, will default to ‘0000’ value  
‘1000’  
to  
‘1111’  
Bit [3:0]  
‘0000’  
‘0001’  
‘0010’  
‘0011’  
‘0100’  
‘0101’  
‘0110’  
‘0111’  
Physical Port 5 is Disabled  
Physical Port 5 is mapped to Logical Port 1  
Physical Port 5 is mapped to Logical Port 2  
Physical Port 5 is mapped to Logical Port 3  
Physical Port 5 is mapped to Logical Port 4  
Physical Port 5 is mapped to Logical Port 5  
Physical Port 5 is mapped to Logical Port 6  
Physical Port 5 is mapped to Logical Port 7  
Reserved, will default to ‘0000’ value  
‘1000’  
to  
‘1111’  
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Datasheet  
8.2.1.34  
Register FEh: PortMap 7  
BIT  
NUMBER  
BIT NAME  
DESCRIPTION  
7:0  
PRTR7  
PortMap register for port 7.  
When a hub is enumerated by a USB host controller, the hub is only  
permitted to report how many ports it has; the hub is not permitted to select  
a numerical range or assignment. The host controller will number the  
downstream ports of the hub starting with the number '1', up to the number  
of ports that the hub reported having.  
The host's port number is referred to as "Logical Port Number" and the  
physical port on the hub is the “Physical Port Number". When mapping mode  
is enabled (see PRTMAP_EN in Register 08h: Configuration Data Byte 3)  
the hub's downstream port numbers can be mapped to different logical port  
numbers (assigned by the host).  
Note:  
OEM must ensure that contiguous logical port numbers are used,  
starting from #1 up to the maximum number of enabled ports; this  
ensures that the hub's ports are numbered in accordance with the  
way a host will communicate with the ports.  
Table 8.6 PortMap Register for Port 7  
Bit [7:4]  
Bit [3:0]  
‘0000’  
to  
‘1111’  
Reserved  
‘0000’  
‘0001’  
‘0010’  
‘0011’  
‘0100’  
‘0101’  
‘0110’  
‘0111’  
Physical Port 7 is Disabled  
Physical Port 7 is mapped to Logical Port 1  
Physical Port 7 is mapped to Logical Port 2  
Physical Port 7 is mapped to Logical Port 3  
Physical Port 7 is mapped to Logical Port 4  
Physical Port 7 is mapped to Logical Port 5  
Physical Port 7 is mapped to Logical Port 6  
Physical Port 7 is mapped to Logical Port 7  
Reserved, will default to ‘0000’ value  
‘1000’  
to  
‘1111’  
SMSC USB251x  
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Datasheet  
8.2.1.35  
Register FFh: Status/Command  
BIT NAME  
BIT  
NUMBER  
DESCRIPTION  
7:3  
2
Reserved  
Reserved  
INTF_PW_DN  
SMBus Interface Power Down  
‘0’ = Interface is active  
‘1’ = Interface power down after ACK has completed  
1
0
RESET  
Reset the SMBus Interface and internal memory back to RESET_N  
assertion default settings.  
‘0’ = Normal Run/Idle State  
‘1’ = Force a reset of registers to their default state  
USB_ATTACH  
USB Attach (and write protect)  
‘0’ = SMBus slave interface is active  
‘1’ = The hub will signal a USB attach event to an upstream device, and the  
internal memory (address range 00h-FEh) is “write-protected” to prevent  
unintentional data corruption.  
2
8.2.2  
I C EEPROM  
The I2C EEPROM interface implements a subset of the I2C Master specification (Please refer to the  
Philips Semiconductor Standard I2C-Bus specification for details on I2C bus protocols). The SMSC  
hub’s I2C EEPROM interface is designed to attach to a single “dedicated” I2C EEPROM, and it  
conforms to the Standard-mode I2C specification (100 kbit/s transfer rate and 7-bit addressing) for  
protocol and electrical compatibility.  
Note: Extensions to the I2C specification are not supported.  
The hub acts as the master and generates the serial clock SCL, controls the bus access (determines  
which device acts as the transmitter and which device acts as the receiver), and generates the START  
and STOP conditions.  
8.2.2.1  
8.2.2.2  
Implementation Characteristics  
The hub will only access an EEPROM using the sequential read protocol.  
Pull-Up Resistor  
The circuit board designer is required to place external pull-up resistors (10 kΩ recommended) on the  
SDA / SMBDATA and SCL / SMBCLK / CFG_SEL[0] lines (per SMBus 1.0 specification, and EEPROM  
manufacturer guidelines) to VDD33 in order to assure proper operation.  
2
8.2.2.3  
I C EEPROM Slave Address  
The slave address is 1010000.  
Note: 10-bit addressing is NOT supported.  
8.2.3  
In-Circuit EEPROM Programming  
The EEPROM can be programmed via ATE (automatic test equipment) by pulling RESET_N low  
(which tri-states the hub’s EEPROM interface and allows an external source to program the EEPROM).  
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8.3  
SMBus Slave Interface  
Instead of loading User-Defined Descriptor data from an external EEPROM, the SMSC hub can be  
configured to receive a code load from an external processor via an SMBus interface. The SMBus  
interface shares the same pins as the EEPROM interface; if CFG_SEL[1] & CFG_SEL[0] activate the  
SMBus interface, external EEPROM support is no longer available (and the user-defined descriptor  
data must be downloaded via the SMBus). The SMSC hub waits indefinitely for the SMBus code load  
to complete and only “appears” as a newly connected device on USB after the code load is complete.  
The hub’s SMBus implementation is a slave-only SMBus device. The implementation only supports  
read block and write block protocols. The hub responds to other protocols as described in Section  
8.3.3, "Invalid Protocol Response Behavior," on page 54. Reference the System Management Bus  
specification, Rev 1.0.  
The SMBus interface is used to read and write the registers in the device. The register set is shown  
in Section 8.2.1, "Internal Register Set (Common to EEPROM and SMBus)," on page 35.  
8.3.1  
8.3.2  
SMBus Slave Addresses  
The SMBus slave address is 58h (01011000b).  
Bus Protocols  
Typical Write Block and Read Block protocols are shown below. Register accesses are performed  
using 7-bit slave addressing, an 8-bit register address field, and an 8-bit data field. The shading  
indicates the hub driving data on the SMBDATA line; otherwise, host data is on the SDA/SMBDATA  
line.  
The slave address is the unique SMBus Interface Address for the hub that identifies it on SMBus. The  
register address field is the internal address of the register to be accessed. The register data field is  
the data that the host is attempting to write to the register or the contents of the register that the host  
is attempting to read.  
Note: Data bytes are transferred MSB first.  
8.3.2.1  
Block Read/Write  
The block write begins with a slave address and a write condition. After the command code, the host  
issues a byte count which describes how many more bytes will follow in the message. If a slave had  
20 bytes to send, the first byte would be the number 20 (14h), followed by the 20 bytes of data. The  
byte count may not be 0. A block read or write is allowed to transfer a maximum of 32 data bytes.  
Note: For the following SMBus tables:  
Denotes Master-to-Slave  
Denotes Slave-to-Master  
1
7
1
1
8
1
S
Slave Address  
Wr  
A
Register Address  
A
...  
8
1
8
1
8
1
8
1
1
Byte Count = N  
A
Data byte 1  
A
Data byte 2  
A
Data byte N  
A
P
Block Write  
Figure 8.1 Block Write  
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Datasheet  
8.3.2.2  
Block Read  
A block read differs from a block write in that the repeated start condition exists to satisfy the I2C  
specification’s requirement for a change in the transfer direction.  
1
7
1
1
8
1
1
7
1
1
S
Slave Address  
Wr  
A
Register Address  
A
S
Slave Address Rd  
A
...  
8
1
8
1
8
1
8
1
1
Byte Count = N  
A
Data byte 1  
A
Data byte 2  
A
Data byte N  
A
P
Block Read  
Figure 8.2 Block Read  
8.3.3  
Invalid Protocol Response Behavior  
Registers that are accessed with an invalid protocol are not updated. A register is only updated  
following a valid protocol. The only valid protocols are write block and read block, which are described  
above. The hub only responds to the hardware selected Slave Address (0101100x).  
Attempting to communicate with the hub over SMBus with an invalid slave address or invalid protocol  
results in no response, and the SMBus Slave Interface returns to the idle state.  
The only valid registers that are accessible by the SMBus slave address are the registers defined in  
the Registers Section. The hub does not respond to undefined registers.  
8.3.4  
8.3.5  
General Call Address Response  
The hub does not respond to a general call address of 0000_000b.  
Slave Device Time-Out  
According to the SMBus specification, version 1.0 devices in a transfer can abort the transfer in  
progress and release the bus when any single clock low interval exceeds 25 ms (TTIMEOUT, MIN).  
Devices that have detected this condition must reset their communication and be able to receive a new  
START condition no later than 35 ms (TTIMEOUT, MAX).  
Note: Some simple devices do not contain a clock low drive circuit; this simple kind of device typically  
resets its communications port after a start or stop condition. The slave device time-out must  
be implemented.  
8.3.6  
8.3.7  
8.3.8  
Stretching the SCLK Signal  
The hub supports stretching of the SCLK by other devices on the SMBus. The hub does not stretch  
the SCLK.  
SMBus Timing  
The SMBus Slave Interface complies with the SMBus AC Timing specification. See the SMBus timing  
in the “Timing Diagram” section.  
Bus Reset Sequence  
The SMBus slave interface resets and returns to the idle state upon a START field followed  
immediately by a STOP field.  
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8.3.9  
SMBus Alert Response Address  
The SMBALERT# signal is not supported by the hub.  
8.3.9.1  
Undefined Registers  
The registers shown in Table 8.2 are the defined registers in the hub. Reads to undefined registers  
return 00h. Writes to undefined registers have no effect and do not return an error.  
8.3.9.2  
Reserved Registers  
Reserved registers should be written to ‘0’ unless otherwise specified. Contents read should be  
ignored.  
8.4  
Default Configuration Option  
To configure the SMSC hub in its default configuration, strap CFG_SEL[2:0] to 00h. This procedure  
configures the hub to the internal defaults and enables the strapping options. Please see Section 8.2.1,  
"Internal Register Set (Common to EEPROM and SMBus)" for the list of the default values. For specific  
pin strapping options, please see Chapter 5, Pin Descriptions for instructions on how to modify the  
default values. Options include port disable and non-removable pin strapping.  
8.5  
8.6  
Default Strapping Options  
The USB251x can be configured via a combination of internal default values and pin strap options.  
Please see Table 8.2 for specific details on how to enable the default/pin-strap configuration option.  
The strapping option pins only cover a limited sub-set of the configuration options. The internal default  
values will be used for the bits & registers that are not controlled by a strapping option pin. Please  
refer to Table 8.2 for the internal default values that are loaded when this option is selected.  
Strap Options  
Table 8.7 Summary of Strap Options  
Part  
Number  
Resistor Value  
(R)  
Notes  
USB251x  
USB251xi  
USB251xA  
USB251xAi  
USB251xB  
USB251xBi  
Normal  
3
3
3
3
47 - 100 kΩ  
10 kΩ  
Internal Pull-Down  
„ Only applicable to port power pins.  
„ Contains a built-in resistor.  
LED  
3
47 - 100 kΩ  
8.6.1  
Non-Removable Strap Option  
The strap function of the NON_REM[x:0] pins are enabled through the internal default configuration.  
The driver type of each strap pin is I/O (no internal pull-up or pull-down for the input function). Use  
this type of strap option for NON_REM[1:0]. Figure 8.3 shows an example of Strap High and Strap  
Low. Use the Strap High configuration to set the strap option value to a ‘1’. Use the Strap Low  
configuration to set the strap option value to ‘0’.  
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+V  
R kΩ  
Primary Function/  
Strap High  
Primary Function/  
Strap Low  
Strap Pin  
HUB  
Strap Pin  
HUB  
R kΩ  
GND  
Figure 8.3 Non-Removable Pin Strap Example  
8.6.2  
Internal Pull-Down (IPD)  
If a pin's strap function is enabled thru hub configuration selection, (Table 8.1 Hub Configuration  
Selection) and the strap pins driver type is IPD/O (internal pull-down for the Input function), use this  
type of strap option.  
The following figure shows an example of Strap High and Strap Low. Use the Strap High configuration  
to set the strap option value to a ‘1’. Use the Strap Low configuration to set the strap option value to 0.  
+V  
R kΩ  
Primary Function/  
Strap High  
Primary Function/  
Strap Low  
Strap Pin (IPD)  
HUB  
Strap Pin (IPD)  
HUB  
VSS  
VSS  
Figure 8.4 Pin Strap Option with IPD Pin Example  
8.6.3  
LED Strap Option  
If a pin’s strap function of the LED pins are enabled thru the internal default configuration, the driver  
type of each strap pin is I/O (no internal pull-up or pull-down for the input function). When the strap  
pin shares functionality with an LED, use this type of strap option.  
The internal logic will drive the LED appropriately (active high or low) depending on the sampled strap  
option. Figure 8.5 shows an example of Strap High and Strap Low. Use the Strap High configuration  
to set the strap option value to a ‘1’. Use the Strap Low configuration to set the strap option value to ‘0’.  
LED/  
R
Strap High  
kΩ  
Strap Pin  
HUB  
Strap Pin  
HUB  
R
LED/  
kΩ  
Strap Low  
Figure 8.5 LED Pin Strap Example  
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USB2513/13i and USB2514/14i Only: The LED_A[x:1]_N pins are sampled after RESET_N negation,  
and the logic values are used to configure the hub if the internal default configuration mode is selected.  
The implementation shown in Figure 8.5 shows a recommended passive scheme. When a pin is  
configured with a "Strap High" configuration, the LED functions with active low signaling, and the PAD  
will "sink" the current from the external supply. When a pin is configured with a "Strap Low"  
configuration, the LED functions with active high signaling, and the PAD will source the current to the  
external LED.  
8.7  
Reset  
There are two different resets that the hub experiences. One is a hardware reset via the RESET_N  
pin and the second is a USB Bus Reset.  
8.7.1  
External Hardware RESET_N  
A valid hardware reset is defined as assertion of RESET_N for a minimum of 1 μs after all power  
supplies are within operating range. While reset is asserted, the hub (and its associated external  
circuitry) consumes less than 500 μA of current from the upstream USB power source.  
Assertion of RESET_N (external pin) causes the following:  
1. All downstream ports are disabled, and PRTPWR power to downstream devices is removed (unless  
BC_EN is enabled).  
2. The PHYs are disabled, and the differential pairs will be in a high-impedance state.  
3. All transactions immediately terminate; no states are saved.  
4. All internal registers return to the default state (in most cases, 00(h)).  
5. The external crystal oscillator is halted.  
6. The PLL is halted.  
The hub is “operational” 500 μs after RESET_N is negated. Once operational, the hub immediately  
reads OEM-specific data from the external EEPROM (if the SMBus option is not disabled).  
8.7.1.1  
RESET_N for Strapping Option Configuration  
Drive Strap  
Outputs to  
inactive  
Start  
completion  
request  
Hardware  
reset  
asserted  
Attach  
USB  
Upstream  
Read Strap  
Options  
USB Reset  
recovery  
Idle  
levels  
response  
t7  
t8  
t1  
t2  
t6  
t5  
t3  
RESET_N  
VSS  
t4  
Strap Pins  
VSS  
Don’t Care  
Valid  
Driven by Hub if strap is an output.  
Don’t Care  
Figure 8.6 Reset_N Timing for Default/Strap Option Mode  
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Table 8.8 Reset_N Timing for Default/Strap Option Mode  
NAME  
DESCRIPTION  
RESET_N Asserted.  
MIN  
TYP  
MAX  
UNITS  
t1  
t2  
t3  
t4  
t5  
t6  
1
μsec  
nsec  
nsec  
μsec  
msec  
msec  
Strap Setup Time  
16.7  
16.7  
Strap Hold Time.  
1400  
2
hub outputs driven to inactive logic states  
USB Attach (See Note).  
1.5  
100  
Host acknowledges attach and signals USB  
Reset.  
100  
t7  
t8  
USB Idle.  
undefined  
msec  
msec  
Completion time for requests (with or without data  
stage).  
5
Notes:  
„
When in bus-powered mode, the hub and its associated circuitry must not consume more than 100  
mA from the upstream USB power source during t1+t5.  
„
All power supplies must have reached the operating levels mandated in Chapter 9, DC Parameters,  
prior to (or coincident with) the assertion of RESET_N.  
8.7.1.2  
RESET_N for EEPROM Configuration  
Start  
completion  
request  
Hardware  
reset  
asserted  
Read EEPROM  
+
Set Options  
Attach  
USB  
Upstream  
Read Strap  
Options  
USB Reset  
recovery  
Idle  
response  
t4  
t6  
t7  
t1  
t5  
t2  
t3  
RESET_N  
VSS  
Figure 8.7 Reset_N Timing for EEPROM Mode  
Table 8.9 Reset_N Timing for EEPROM Mode  
NAME  
DESCRIPTION  
MIN  
TYP  
MAX  
UNITS  
t1  
t2  
t3  
t4  
RESET_N Asserted.  
1
μsec  
μsec  
msec  
msec  
Hub Recovery/Stabilization.  
EEPROM Read / Hub Config.  
USB Attach (See Note).  
500  
99.5  
100  
2.0  
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Table 8.9 Reset_N Timing for EEPROM Mode (continued)  
NAME  
DESCRIPTION  
MIN  
TYP  
MAX  
UNITS  
t5  
Host acknowledges attach and signals USB  
Reset.  
100  
msec  
t6  
t7  
USB Idle.  
undefined  
msec  
msec  
Completion time for requests (with or without data  
stage).  
5
Notes:  
„
When in bus-powered mode, the hub and its associated circuitry must not consume more than 100  
mA from the upstream USB power source during t4+t5+t6+t7.  
„
All power supplies must have reached the operating levels mandated in Chapter 9, DC Parameters,  
prior to (or coincident with) the assertion of RESET_N.  
8.7.1.3  
RESET_N for SMBus Slave Configuration  
Start  
completion  
request  
Hardware  
reset  
asserted  
Attach  
USB  
Upstream  
Reset  
Negation  
SMBus Code  
Load  
Hub PHY  
Stabilization  
USB Reset  
recovery  
Idle  
response  
t6  
t7  
t1  
t5  
t2  
t3  
t4  
RESET_N  
VSS  
Figure 8.8 Reset_N Timing for SMBus Mode  
Table 8.10 Reset_N Timing for SMBus Mode  
NAME  
DESCRIPTION  
MIN  
TYP  
MAX  
UNITS  
t1  
t2  
t3  
t4  
t5  
RESET_N Asserted.  
1
μsec  
μsec  
msec  
msec  
msec  
Hub Recovery/Stabilization.  
SMBus Code Load (See Note).  
Hub Configuration and USB Attach.  
500  
300  
100  
250  
Host acknowledges attach and signals USB  
Reset.  
100  
t6  
t7  
USB Idle.  
Undefined  
msec  
msec  
Completion time for requests (with or without data  
stage).  
5
Notes:  
„
For bus-powered configurations, the 99.5 ms (MAX) is required, and the hub and its associated  
circuitry must not consume more than 100 mA from the upstream USB power source during  
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t2+t3+t4+t5+t6+t7. For Self-Powered configurations, t3 MAX is not applicable and the time to load  
the configuration is determined by the external SMBus host.  
„
All power supplies must have reached the operating levels mandated in Chapter 9, DC Parameters,  
prior to (or coincident with) the assertion of RESET_N.  
8.7.2  
USB Bus Reset  
In response to the upstream port signaling a reset to the hub, the hub does the following:  
Note: The hub does not propagate the upstream USB reset to downstream devices.  
1. Sets default address to 0.  
2. Sets configuration to: Unconfigured.  
3. Negates PRTPWR[x:1] to all downstream ports unless battery charging (BC_EN) is enabled.  
4. Clears all TT buffers.  
5. Moves device from suspended to active (if suspended).  
6. Complies with Section 11.10 of the USB 2.0 specification for behavior after completion of the reset  
sequence. The host then configures the hub and the hub’s downstream port devices in accordance  
with the USB specification.  
Note: The hub does not propagate the upstream USB reset to downstream devices.  
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Chapter 9 DC Parameters  
9.1  
Maximum Guaranteed Ratings  
PARAMETER  
SYMBOL  
MIN  
MAX  
UNITS  
COMMENTS  
Storage  
Temperature  
TSTOR  
-55  
150  
°C  
Lead  
Temperature  
Refer to JEDEC Specification J-STD-  
020D.  
VDD33  
PLLFILT  
CRFILT  
3.3 V supply  
voltage  
4.6  
V
Applies to all parts.  
Voltage on any  
I/O pin  
-0.5  
-0.5  
-0.5  
5.5  
4.0  
2.5  
V
V
V
Voltage on  
XTALIN  
Voltage on  
XTALOUT  
Note 9.1 Stresses above the specified parameters could cause permanent damage to the device.  
This is a stress rating only and functional operation of the device at any condition above  
those indicated in the operation sections of this specification is not implied.  
Note 9.2 When powering this device from laboratory or system power supplies, it is important that  
the absolute maximum ratings not be exceeded or device failure can result. Some power  
supplies exhibit voltage spikes on their outputs when the AC power is switched on or off.  
In addition, voltage transients on the AC power line may appear on the DC output. When  
this possibility exists, it is suggested that a clamp circuit be used.  
9.2  
Operating Conditions  
PARAMETER  
SYMBOL  
MIN  
MAX  
UNITS  
COMMENTS  
Commercial  
Operating  
Temperature  
Ambient temperature in still air.  
Only applies to USB251x and  
USB251xA products.  
TA  
0
70  
°C  
Extended  
Commercial  
Operating  
Ambient temperature in still air.  
TAE  
Only applies to USB251xB products.  
0
85  
85  
°C  
°C  
Temperature  
Industrial  
Operating  
Temperature  
Ambient temperature in still air.  
Only applies to USB251xi,  
USB251xAi, and USB251xBi  
products.  
TAI  
-40  
3.3 V supply voltage  
VDD33  
tRT  
3.0  
0
3.6  
V
Applies to all parts.  
See Figure 9.1  
3.3 V supply rise  
time  
400  
μs  
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PARAMETER  
SYMBOL  
MIN  
MAX  
UNITS  
COMMENTS  
Voltage on any I/O  
pin  
-0.3  
5.5  
V
If any 3.3 V supply voltage drops  
below 3.0 V, then the MAX becomes:  
(3.3 V supply voltage) + 0.5  
Voltage on XTALIN  
-0.3  
VDD33  
V
Voltage  
VDD33  
tRT  
3.3 V  
100%  
90%  
10%  
VSS  
t90%  
Time  
t10%  
Figure 9.1 Supply Rise Time Model  
Table 9.1 DC Electrical Characteristics  
PARAMETER  
SYMBOL  
MIN  
TYP  
MAX  
UNITS  
COMMENTS  
I, IS Type Input Buffer  
Low Input Level  
VILI  
VIHI  
IIL  
0.8  
V
V
TTL Levels  
High Input Level  
2.0  
-10  
250  
Input Leakage  
+10  
350  
μA  
mV  
VIN = 0 to VDD33  
Hysteresis (‘IS’ Only)  
VHYSI  
Input Buffer with Pull-Up (IPU)  
Low Input Level  
VILI  
VIHI  
IILL  
0.8  
V
V
TTL Levels  
High Input Level  
2.0  
+35  
-10  
Low Input Leakage  
High Input Leakage  
+90  
+10  
μA  
μA  
VIN = 0  
IIHL  
VIN = VDD33  
Input Buffer with Pull-Down (IPD)  
Low Input Level  
VILI  
VIHI  
IILL  
0.8  
V
V
TTL Levels  
High Input Level  
2.0  
+10  
-35  
Low Input Leakage  
-10  
-90  
μA  
μA  
VIN = 0  
High Input Leakage  
IIHL  
VIN = VDD33  
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Table 9.1 DC Electrical Characteristics (continued)  
PARAMETER  
SYMBOL  
MIN  
TYP  
MAX  
UNITS  
COMMENTS  
USB251x/xi/xA/xAi  
ICLK Input Buffer  
VILCK  
VIHCK  
IIL  
0.5  
V
V
Low Input Level  
High Input Level  
Input Leakage  
1.4  
-10  
+10  
μA  
VIN = 0 to VDD33  
USB251xB/xBi  
ICLK Input Buffer  
VILCK  
VIHCK  
IIL  
0.3  
V
V
Low Input Level  
0.9  
-10  
High Input Level  
+10  
μA  
Input Leakage  
VIN = 0 to VDD33  
O12, I/O12 &I/OSD12 Type Buffer  
Low Output Level  
VOL  
VOH  
0.4  
V
V
IOL = 12 mA @  
VDD33 = 3.3 V  
High Output Level  
Output Leakage  
2.4  
-10  
250  
IOH = -12 mA @  
VDD33 = 3.3 V  
IOL  
+10  
350  
μA  
mV  
Hysteresis (‘SD’ pad only)  
VHYSC  
VIN = 0 to VDD33  
(Note 9.1)  
Note 9.3 Output leakage is measured with the current pins in high impedance.  
Note 9.4 See USB 2.0 specification for USB DC electrical characteristics.  
Table 9.2 Supply Current Unconfigured: Hi-Speed Host (ICCINTHS  
)
PART  
MIN  
TYP  
MAX  
UNITS  
COMMENTS  
USB2512/12i/12A/12Ai  
USB2512B/12Bi  
USB2513/13i  
90  
40  
95  
45  
mA  
95  
105  
45  
USB2513B/13Bi  
USB2514/14i  
40  
95  
105  
50  
USB2514B/14Bi  
USB2517/17i  
45  
120  
130  
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Table 9.3 Supply Current Unconfigured: Full-Speed Host (ICCINTFS  
)
PART  
MIN  
TYP  
MAX  
UNITS  
COMMENTS  
USB2512/12i/12A/12Ai  
USB2512B/12Bi  
USB2513/13i  
80  
35  
85  
40  
90  
40  
90  
40  
115  
mA  
80  
USB2513B/13Bi  
USB2514/14i  
35  
80  
USB2514B/14Bi  
USB2517/17i  
35  
105  
Table 9.4 Supply Current Configured: Hi-Speed Host (IHCH1  
)
PART  
MIN  
TYP  
MAX  
UNITS  
COMMENTS  
USB2512  
130  
130  
120  
120  
60  
155  
160  
145  
150  
65  
mA  
This is the base current of one  
downstream port.  
USB2512i  
USB2512A  
USB2512Ai  
USB2512B  
USB2512Bi  
USB2513  
60  
70  
150  
150  
65  
180  
185  
70  
USB2513i  
USB2513B  
USB2513Bi  
USB2514  
65  
75  
155  
155  
70  
200  
205  
80  
USB2514i  
USB2514B  
USB2514Bi  
USB2517  
70  
85  
240  
240  
275  
280  
USB2517i  
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Table 9.4 Supply Current Configured: Hi-Speed Host (IHCH1  
)
PART  
MIN  
TYP  
MAX  
UNITS  
COMMENTS  
1 port  
base  
1 port  
base  
USB251x/xi/xA/xAi  
Supply Current Configured  
Hi-Speed Host, each additional  
downstream port  
+
+
mA  
15 mA  
40 mA  
1 port  
base  
1 port  
base  
USB251xB/xBi  
Supply Current Configured  
Hi-Speed Host, each additional  
downstream port  
+
+
mA  
25 mA  
25 mA  
Table 9.5 Supply Current Configured: Full-Speed Host (IFCC1  
)
PART  
MIN  
TYP  
MAX  
UNITS  
COMMENTS  
USB2512  
105  
105  
95  
125  
135  
115  
125  
50  
mA  
This is the base current of one  
downstream port.  
USB2512i  
USB2512A  
USB2512Ai  
USB2512B  
USB2512Bi  
USB2513  
95  
45  
45  
55  
125  
125  
50  
135  
140  
55  
USB2513i  
USB2513B  
USB2513Bi  
USB2514  
50  
60  
140  
140  
50  
150  
155  
60  
USB2514i  
USB2514B  
USB2514Bi  
USB2517  
50  
65  
215  
215  
220  
225  
USB2517i  
1 port  
base  
1 port  
base  
USB251x/xi/xA/xAi  
There is no additional current for  
additional ports.  
Supply Current Configured  
Full-Speed Host, each additional  
downstream port  
+
+
mA  
mA  
0 mA  
0 mA  
1 port  
base  
1 port  
base  
USB251xB/xBi  
Supply Current Configured  
Full-Speed Host, each additional  
downstream port  
+
+
8 mA  
8 mA  
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Table 9.6 USB251x/xi/xA/xAi Supply Current Suspend (ICSBY  
)
PART  
USB2512/12A  
MIN  
TYP  
MAX  
UNITS  
COMMENTS  
310  
310  
310  
310  
310  
310  
310  
310  
420  
600  
420  
550  
420  
600  
610  
800  
μA  
All supplies combined  
USB2512i/12Ai  
USB2513  
USB2513i  
USB2514  
USB2514i  
USB2517  
USB2517i  
Table 9.7 USB251xB/xBi Supply Current Suspend (ICSBY  
)
PART  
MIN  
TYP  
475  
MAX  
1000  
UNITS  
COMMENTS  
USB2512B  
USB2512Bi  
USB2513B  
USB2513Bi  
USB2514B  
USB2514Bi  
μA  
All supplies combined  
475  
500  
500  
550  
550  
1200  
1100  
1300  
1200  
1500  
Table 9.8 USB251x/xi/xA/xAi Supply Current Reset (ICRST  
)
PART  
MIN  
TYP  
105  
MAX  
275  
UNITS  
COMMENTS  
USB2512/12A  
USB2512i/12Ai  
USB2513  
μA  
All supplies combined  
105  
105  
100  
100  
100  
115  
115  
400  
230  
350  
275  
400  
320  
600  
USB2513i  
USB2514  
USB2514i  
USB2517  
USB2517i  
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SMSC USB251x  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Table 9.9 USB251xB/xBi Supply Current Reset (ICRST  
)
PART  
MIN  
TYP  
MAX  
UNITS  
COMMENTS  
All supplies combined  
USB2512B  
USB2512Bi  
USB2513B  
USB2513Bi  
USB2514B  
USB2514Bi  
550  
550  
650  
650  
750  
750  
1100  
1250  
1200  
1400  
1400  
1600  
μA  
Table 9.10 Pin Capacitance for USB251x, USB251xi, USB251xA, USB251xAi  
LIMITS  
PARAMETER  
SYMBOL  
MIN  
TYP MAX UNIT  
TEST CONDITION  
Clock Input  
Capacitance  
CXTAL  
2
pF  
All pins except USB pins and the pins  
under the test tied to AC ground.  
Input Capacitance  
Output Capacitance  
CIN  
10  
20  
pF  
pF  
(See Note 9.5)  
COUT  
Table 9.11 Pin Capacitance for USB251xB and USB251xBi  
LIMITS  
PARAMETER  
SYMBOL  
MIN  
TYP MAX UNIT  
TEST CONDITION  
Clock Input  
Capacitance  
CXTAL  
6
pF  
All pins except USB pins and the pins  
under the test tied to AC ground.  
Input Capacitance  
Output Capacitance  
CIN  
6
6
pF  
pF  
(See Note 9.5)  
COUT  
Note 9.5 Capacitance TA = 25°C; fc = 1 MHz; VDD33 = 3.3 V  
SMSC USB251x  
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9.2.1  
Package Thermal Specifications  
Thermal parameters are measured or estimated for devices with the exposed pad soldered to thermal  
vias in a multilayer 2S2P PCB per JESD51. Thermal resistance is measured from the die to the  
ambient air. The values provided are based on the package body, die size, maximum power  
consumption, 85°C ambient temperature, and 125°C junction temperature of the die.  
Table 9.12 Package Thermal Resistance Parameters  
USB2512/12i  
USB2513/13i  
USB2514/14i  
USB2512B/12Bi  
USB2513B/13Bi  
USB2514B/14Bi  
USB2513/13i  
USB2514/14i  
USB2512A/12Ai  
VELOCITY  
SYMBOL  
(°C/W)  
(°C/W)  
(°C/W)  
(°C/W)  
(meters/sec)  
36-PIN QFN  
48-PIN QFN  
-
PACKAGE  
34.2  
29.9  
0.3  
36.2  
33.4  
0.4  
40.1  
35.0  
0.5  
31.6  
27.6  
0.3  
0
1
0
1
0
1
ΘJA  
ΨJT  
ΘJC  
0.5  
0.7  
0.7  
0.4  
3.0  
5.1  
6.3  
3.0  
3.0  
5.1  
6.3  
3.0  
Use the following formulas to calculate the junction temperature:  
TJ = P x ΘJA + TA  
TJ = P x ΨJT + TT  
TJ = P x ΘJC + TC  
Table 9.13 Legend  
SYMBOL  
DESCRIPTION  
Junction temperature  
TJ  
P
Power dissipated  
ΘJA  
ΘJC  
ΨJT  
TA  
Junction-to-ambient-temperature  
Junction-to-top-of-package  
Junction-to-bottom-of-case  
Ambient temperature  
TC  
TT  
Temperature of the bottom of the case  
Temperature of the top of the case  
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Datasheet  
Chapter 10 AC Specifications  
10.1  
Oscillator/Crystal  
Crystal: Parallel Resonant, Fundamental Mode, 24/481 MHz ±350 ppm.  
External Clock: 50% Duty cycle ± 10%, 24/48 MHz ± 350 ppm, Jitter < 100 ps rms.  
XTAL1  
(CS1 = CB1 + CXTAL1  
)
C1  
1 M  
Crystal  
CL  
C0  
C2  
XTAL2  
(CS2 = CB2 + CXTAL2  
)
Figure 10.1 Typical Crystal Circuit  
Table 10.1 Crystal Circuit Legend  
SYMBOL  
DESCRIPTION  
IN ACCORDANCE WITH  
C0  
CL  
CB  
Crystal shunt capacitance  
Crystal load capacitance  
Crystal manufacturer’s specification (See Note 10.1)  
OEM board design  
Total board or trace  
capacitance  
CS  
Stray capacitance  
SMSC IC and OEM board design  
SMSC IC  
CXTAL  
C1  
XTAL pin input capacitance  
Load capacitors installed on  
OEM board  
Calculated values based on Figure 10.2, "Formula  
to Find the Value of C1 and C2" (See Note 10.2)  
C2  
C1 = 2 x (CL – C0) – CS1  
C2 = 2 x (CL – C0) – CS2  
Figure 10.2 Formula to Find the Value of C1 and C2  
Note 10.1 C0 is usually included (subtracted by the crystal manufacturer) in the specification for CL  
and should be set to ‘0’ for use in the calculation of the capacitance formulas in  
Figure 10.2, "Formula to Find the Value of C1 and C2". However, the OEM PCB itself may  
present a parasitic capacitance between XTALIN and XTALOUT. For an accurate  
calculation of C1 and C2, take the parasitic capacitance between traces XTALIN and  
XTALOUT into account.  
Note 10.2 Each of these capacitance values is typically approximately 18 pF.  
1.Only when SEL48 is available and supported.  
SMSC USB251x  
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10.2  
Ceramic Resonator  
24 MHz ± 350 ppm  
XTAL1  
24 MHz  
Ceramic  
Resonator  
1 M  
XTAL2  
Figure 10.3 Ceramic Resonator Usage with SMSC IC  
10.3  
External Clock  
50% Duty cycle ± 10%, 24 MHz ± 350 ppm, Jitter < 100 ps rms.  
The external clock is recommended to conform to the signaling level designated in the JESD76-2  
specification on 1.8 V CMOS Logic. XTALOUT should be treated as a no connect.  
10.3.1  
SMBus Interface  
The SMSC Hub conforms to all voltage, power, and timing characteristics and specifications as set  
forth in the SMBus 1.0 specification for Slave-Only devices (except as noted in Section 8.3, "SMBus  
Slave Interface," on page 53.  
2
10.3.2  
10.3.3  
I C EEPROM  
Clock frequency is fixed at 60 KHz ± 20%.  
USB 2.0  
The SMSC Hub conforms to all voltage, power, and timing characteristics and specifications as set  
forth in the USB 2.0 specification. Please refer to the USB 2.0 specification for more information.  
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SMSC USB251x  
DATASHEET  
USB 2.0 High-Speed 2-Port Hub Controller  
Datasheet  
Revision 1.1 (04-26-10)  
71  
SMSC USB251x  
DATASHEET  
USB 2.0 High-Speed 2-Port Hub Controller  
Datasheet  
Revision 1.1 (04-26-10)  
72  
SMSC USB251x  
DATASHEET  
USB 2.0 High-Speed 2-Port Hub Controller  
Datasheet  
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DATASHEET  
USB 2.0 Hi-Speed Hub Controller  
Datasheet  
11.1  
Tape and Reel Specifications  
Figure 11.4 36-Pin Package Tape Specifications  
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USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Figure 11.5 48-Pin Package Tape Specifications  
SMSC USB251x  
75  
Revision 1.1 (04-26-10)  
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USB 2.0 Hi-Speed Hub Controller  
Datasheet  
Figure 11.6 36-Pin and 48-Pin Package Reel Specifications  
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76  
SMSC USB251x  
DATASHEET  

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