X9428WS-2.7 [XICOR]

Single Digitally Controlled Potentiometer; 单数字控制电位器
X9428WS-2.7
型号: X9428WS-2.7
厂家: XICOR INC.    XICOR INC.
描述:

Single Digitally Controlled Potentiometer
单数字控制电位器

电位器
文件: 总20页 (文件大小:581K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
APPLICATION NOTES  
A V A I L A B L E  
AN99 • AN115 • AN120 • AN124 • AN133 • AN134 • AN135  
Low Noise/Low Power/2-Wire Bus  
X9428  
Single Digitally Controlled Potentiometer (XDCP)  
FEATURES  
DESCRIPTION  
• Solid state potentiometer  
• 2-wire serial interface  
• Register oriented format  
—Direct Read/Write/Transfer Wiper Position  
—Store as many as Four Positions per  
Potentiometer  
The X9428 integrates  
potentiometers (XDCP) on a monolithic CMOS  
integrated microcircuit.  
a
digitally controlled  
The digitally controlled potentiometer is implemented  
using 63 resistive elements in a series array. Between  
each element are tap points connected to the wiper  
terminal through switches. The position of the wiper on  
the array is controlled by the user through the 2-wire  
bus interface. Each potentiometer has associated with  
it a volatile Wiper Counter Register (WCR) and 4  
nonvolatile Data Registers (DR0:DR3) that can be  
directly written to and read by the user.The contents of  
the WCR controls the position of the wiper on the  
resistor array through the switches. Power up recalls  
the contents of DR0 to the WCR.  
• Power supplies  
—V  
= 2.7V to 5.5V  
CC  
—V+ = 2.7V to 5.5V  
—V– = –2.7V to –5.5V  
• Low power CMOS  
—Standby current < 1µA  
—Ideal for Battery Operated Applications  
• High reliability  
Endurance–100,000 Data Changes per Bit per  
Register  
—Register Data Retention–100 years  
• 4-bytes of nonvolatile memory  
• 10K Ohm resistor array  
• Resolution: 64 taps each potentiometer  
• SOIC and TSSOP packages  
The XDCP can be used as  
a three-terminal  
potentiometer or as a two-terminal variable resistor in  
a wide variety of applications including control,  
parameter adjustments, and signal processing.  
BLOCK DIAGRAM  
V
V
CC  
SS  
V+  
V–  
R0 R1  
R2 R3  
V /R  
H
H
SCL  
Wiper  
Counter  
Register  
(WCR)  
Interface  
and  
Control  
SDA  
A0  
V /R  
8
L
L
A2  
A3  
Circuitry  
V
/R  
W
Data  
W
WP  
Characteristics subject to change without notice. 1 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
PIN DESCRIPTIONS  
Host Interface Pins  
Serial Clock (SCL)  
PIN CONFIGURATION  
DIP/SOIC  
X9428  
V+  
1
2
3
4
5
6
7
8
16  
15  
14  
13  
12  
11  
10  
9
V
CC  
A2  
NC  
A0  
The SCL input is used to clock data into and out of the  
X9428.  
R /V  
L
L
NC  
A3  
R /V  
H
H
Serial Data (SDA)  
R
/V  
W
W
SCL  
NC  
V–  
SDA is a bidirectional pin used to transfer data into and  
out of the device. It is an open drain output and may be  
wire-ORed with any number of open drain or open  
collector outputs. An open drain output requires the  
use of a pull-up resistor. For selecting typical values,  
refer to the guidelines for calculating typical values on  
the bus pull-up resistors graph.  
SDA  
WP  
V
SS  
TSSOP  
X9428  
V
Device Address (A , A , A )  
A2  
CC  
1
2
3
4
5
6
7
14  
13  
12  
11  
10  
9
0
2
3
R
L
V+  
The Address inputs are used to set the least significant  
3 bits of the 8-bit slave address. A match in the slave  
address serial data stream must be made with the  
Address input in order to initiate communication with  
the X9428. A maximum of 8 devices may occupy the  
2-wire serial bus.  
A0  
R
H
NC  
A3  
R
W
SDA  
WP  
SCL  
V–  
V
8
SS  
Potentiometer Pins  
PIN NAMES  
R /V , R /V  
L
H
H
L
The R /V and R /V inputs are equivalent to the  
terminal connections on either end of a mechanical  
potentiometer.  
H
H
L
L
Symbol  
SCL  
Description  
Serial clock  
Serial data  
SDA  
R /V  
W
W
A0, A2, A3  
Device address  
The wiper outputs are equivalent to the wiper output of  
a mechanical potentiometer.  
R /V , V /R  
Potentiometer Pins  
(terminal equivalent)  
H
H
L
H
R /V  
W
Potentiometer Pin (wiper equivalent)  
Hardware write protection  
Analog and voltage follower  
System supply voltage  
System ground  
W
Hardware Write Protect Input WP  
WP  
The WP pin when low prevents nonvolatile writes to the  
Data Registers.  
V+,V-  
V
CC  
Analog Supply V+, V-  
V
SS  
The Analog Supply V+, V- are the supply voltages for  
the XDCP analog section.  
NC  
No connection  
Characteristics subject to change without notice. 2 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
PRINCIPLES OF OPERATION  
The X9428 will respond with an acknowledge after  
recognition of a start condition and its slave address  
and once again after successful receipt of the  
command byte. If the command is followed by a data  
byte the X9428 will respond with a final acknowledge.  
The X9428 is  
a
highly integrated microcircuit  
incorporating a resistor array and its associated  
registers and counters and the serial interface logic  
providing direct communication between the host and  
the XDCP potentiometers.  
Array Description  
The X9428 is comprised of a resistor array. The array  
contains 63 discrete resistive segments that are  
connected in series. The physical ends of the array are  
equivalent to the fixed terminals of a mechanical  
Serial Interface  
The X9428 supports a bidirectional bus oriented  
protocol. The protocol defines any device that sends  
data onto the bus as a transmitter and the receiving  
device as the receiver. The device controlling the  
transfer is a master and the device being controlled is  
the slave. The master will always initiate data transfers  
and provide the clock for both transmit and receive  
operations. Therefore, the X9428 will be considered a  
slave device in all applications.  
potentiometer (V /R and V /R inputs).  
H
H
L
L
At both ends of the array and between each resistor  
segment is a CMOS switch connected to the wiper  
(V /R ) output. Within each individual array only one  
W
W
switch may be turned on at a time. These switches are  
controlled by the Wiper Counter Register (WCR). The  
six bits of the WCR are decoded to select, and enable,  
one of sixty-four switches.  
Clock and Data Conventions  
Data states on the SDA line can change only during  
The WCR may be written directly, or it can be changed  
by transferring the contents of one of four associated  
Data Registers into the WCR. These Data Registers  
and the WCR can be read and written by the host  
system.  
SCL LOW periods (t  
). SDA state changes during  
LOW  
SCL HIGH are reserved for indicating start and stop  
conditions.  
Start Condition  
All commands to the X9428 are preceded by the start  
condition, which is a HIGH to LOW transition of SDA  
Device Addressing  
Following a start condition the master must output the  
address of the slave it is accessing. The most  
significant four bits of the slave address are the device  
type identifier (refer to Figure 1 below). For the X9428  
this is fixed as 0101[B].  
while SCL is HIGH (t  
). The X9428 continuously  
HIGH  
monitors the SDA and SCL lines for the start condition  
and will not respond to any command until this  
condition is met.  
Stop Condition  
Figure 1. Slave Address  
All communications must be terminated by a stop  
condition, which is a LOW to HIGH transition of SDA  
while SCL is HIGH.  
Device Type  
Identifier  
Acknowledge  
0
1
0
1
A3  
A2  
0
A0  
Acknowledge is a software convention used to provide  
a positive handshake between the master and slave  
devices on the bus to indicate the successful receipt of  
data. The transmitting device, either the master or the  
slave, will release the SDA bus after transmitting eight  
bits. The master generates a ninth clock cycle and  
during this period the receiver pulls the SDA line LOW  
to acknowledge that it successfully received the eight  
bits of data.  
Device Address  
The next four bits of the slave address are the device  
address. The physical device address is defined by the  
state of the A , A , A inputs.The X9428 compares the  
serial data stream with the address input state; a  
successful compare of all four address bits is required  
0
2
3
for the X9428 to respond with an acknowledge.The A ,  
0
A , A inputs can be actively driven by CMOS input  
2
3
signals or tied to V or V  
.
CC  
SS  
Characteristics subject to change without notice. 3 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
Acknowledge Polling  
Figure 2. Instruction Byte Format  
The disabling of the inputs, during the internal  
nonvolatile write operation, can be used to take  
advantage of the typical 5ms EEPROM write cycle  
time. Once the stop condition is issued to indicate the  
end of the nonvolatile write command the X9428  
initiates the internal write cycle. ACK polling can be  
initiated immediately. This involves issuing the start  
condition followed by the device slave address. If the  
X9428 is still busy with the write operation no ACK will  
be returned. If the X9428 has completed the write  
operation an ACK will be returned, and the master can  
then proceed with the next operation.  
Register  
Select  
I3  
I2  
I1  
I0  
R1 R0  
0
0
Instructions  
The four high order bits define the instruction. The next  
two bits (R1 and R0) select one of the four registers  
that is to be acted upon when a register oriented  
instruction is issued. Bits 0 and 1 are defined to be 0.  
Flow 1. ACK Polling Sequence  
Four of the seven instructions end with the  
transmission of the instruction byte. The basic  
sequence is illustrated in Figure 3. These two-byte  
instructions exchange data between the Wiper Counter  
Register and one of the Data Registers. A transfer from  
a Data Register to a Wiper Counter Register is  
essentially a write to a static RAM. The response of the  
Nonvolatile Write  
Command Completed  
Enter ACK Polling  
Issue  
START  
wiper to this action will be delayed t  
. A transfer  
WRL  
from the Wiper Counter Register (current wiper  
position), to a Data Register is a write to nonvolatile  
memory and takes a minimum of t  
to complete.  
Issue Slave  
Issue STOP  
Address  
WR  
Four instructions require a three-byte sequence to  
complete. These instructions transfer data between the  
host and the X9428; either between the host and one  
of the Data Registers or directly between the host and  
the Wiper Counter Register. These instructions are:  
Read Wiper Counter Register (read the current wiper  
position of the selected pot), write Wiper Counter  
Register (change current wiper position of the selected  
pot), read Data Register (read the contents of the  
selected nonvolatile register) and write Data Register  
(write a new value to the selected Data Register). The  
sequence of operations is shown in Figure 4.  
ACK  
Returned?  
NO  
YES  
NO  
Further  
Operation?  
YES  
Issue  
Instruction  
Issue STOP  
Proceed  
Proceed  
Instruction Structure  
The next byte sent to the X9428 contains the instruction  
and register pointer information. The four most  
significant bits are the instruction. The next four bits  
point to one of four associated registers. The format is  
shown below in Figure 2.  
Characteristics subject to change without notice. 4 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
Figure 3. Two-Byte Instruction Sequence  
SCL  
SDA  
S
T
A
R
T
0
1
0
1
A3 A2  
0
A0  
A
C
K
I3 I2  
I1 I0 R1 R0  
0
0
A
C
K
S
T
O
P
The Increment/Decrement command is different from  
the other commands. Once the command is issued  
and the X9428 has responded with an acknowledge,  
the master can clock the selected wiper up and/or  
down in one segment steps; thereby, providing a fine  
tuning capability to the host. For each SCL clock pulse  
move one resistor segment towards the V /R  
H H  
terminal. Similarly, for each SCL clock pulse while SDA  
is LOW, the selected wiper will move one resistor  
segment towards the V /R terminal. A detailed  
L
L
illustration of the sequence and timing for this  
operation are shown in Figures 5 and 6 respectively.  
(t  
) while SDA is HIGH, the selected wiper will  
HIGH  
Table 1. Instruction Set  
Instruction  
Instruction Set  
I
I
I
I
R
R
X
X
0
Operation  
3
2
1
0
1
0
1
Read Wiper Counter  
Register  
1
1
1
1
1
1
0
0
0
0
1
1
1
0
0
1
1
0
0
1
1
1
0
1
0
1
0
0
0
0
0
0
Read the contents of the Wiper Counter Register  
Write Wiper Counter  
Register  
0
0
0
0
0
0
0
0
0
0
0
0
0
Write new value to the Wiper Counter Register  
Read Data Register  
1/0 1/0  
1/0 1/0  
1/0 1/0  
1/0 1/0  
Read the contents of the Data Register pointed to  
by R –R  
1
0
Write Data Register  
Write new value to the Data Register pointed to by  
R –R  
1
0
XFR Data Register to  
Wiper Counter Register  
Transfer the contents of the Data Register pointed  
to by R –R to its Wiper Counter Register  
1
0
XFR Wiper Counter  
Register to Data Register  
Transfer the contents of the Wiper Counter Register  
to the Data Register pointed to by R –R  
1
0
Increment/Decrement  
Wiper Counter Register  
0
0
1/0 Enable Increment/decrement of the Wiper Counter  
Register  
Note: (7) 1/0 = data is one or zero  
Characteristics subject to change without notice. 5 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
Figure 4. Three-Byte Instruction Sequence  
SCL  
SDA  
S
T
A
R
T
0
1
0
1
A3 A2 0 A0  
A
C
K
I3 I2  
I1 I0 R1 R0  
0
0
A
C
K
0
0
D5 D4 D3 D2 D1 D0  
A
C
K
S
T
O
P
Figure 5. Increment/Decrement Instruction Sequence  
SCL  
SDA  
X
X
S
T
A
R
T
0
1
0
1
A3 A2  
0
A0  
A
C
K
I3 I2  
I1 I0 R1 R0  
0
0
A
C
K
I
I
D
E
C
1
S
T
I
D
N
C
1
N
C
2
N
C
n
E
C
n
O
P
Figure 6. Increment/Decrement Timing Limits  
INC/DEC  
CMD  
Issued  
t
WRID  
SCL  
SDA  
Voltage Out  
V
/R  
W
W
Characteristics subject to change without notice. 6 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
Figure 7. Acknowledge Response from Receiver  
SCL from  
Master  
1
8
9
Data Output  
from Transmitter  
Data Output  
from Receiver  
START  
Acknowledge  
Figure 8. Detailed Potentiometer Block Diagram  
Serial Data Path  
Serial  
Bus  
Input  
V /R  
H H  
From Interface  
Circuitry  
C
o
u
n
t
Register 0  
Register 2  
Register 1  
8
6
Parallel  
Bus  
Input  
e
r
Wiper  
D
e
c
o
d
e
Register 3  
Counter  
Register  
(WCR)  
INC/DEC  
Logic  
If WCR = 00[H] then V /R = V /R  
W
W
L
L
UP/DN  
UP/DN  
If WCR = 3F[H] then V /R = V /R  
H
W
W
H
V /R  
Modified SCL  
L
L
CLK  
V
/R  
W
W
Characteristics subject to change without notice. 7 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
DETAILED OPERATION  
Register Descriptions  
The potentiometer has a Wiper Counter Register and  
four Data Registers. A detailed discussion of the  
register organization and array operation follows.  
Data Registers, (6-Bit), Nonvolatile  
D5  
NV  
D4  
NV  
D3  
NV  
D2  
NV  
D1  
NV  
D0  
NV  
Wiper Counter Register  
(MSB)  
(LSB)  
The X9428 contains a Wiper Counter Register. The  
Wiper Counter Register can be envisioned as a 6-bit  
parallel and serial load counter with its outputs  
decoded to select one of sixty-four switches along its  
resistor array. The contents of the WCR can be altered  
in four ways: it may be written directly by the host via  
the write Wiper Counter Register instruction (serial  
load); it may be written indirectly by transferring the  
contents of one of four associated Data Registers via  
the XFR Data Register instruction (parallel load); it can  
be modified one step at a time by the Increment/  
Decrement instruction. Finally, it is loaded with the  
contents of its Data Register zero (DR0) upon power-  
up.  
Four 6-bit Data Registers for each XDCP. (eight 6-bit  
registers in total).  
– {D5~D0}: These bits are for general purpose not  
volatile data storage or for storage of up to four  
different wiper values. The contents of Data Register  
0 are automatically moved to the Wiper Counter  
Register on power-up.  
Wiper Counter Register, (6-Bit), Volatile  
WP5  
V
WP4  
V
WP3  
V
WP2  
V
WP1  
V
WP0  
V
(MSB)  
(LSB)  
The WCR is a volatile register; that is, its contents are  
lost when the X9428 is powered-down. Although the  
register is automatically loaded with the value in DR0  
upon power-up, it should be noted this may be different  
from the value present at power-down.  
One 6-bit wiper counter register for each XDCP. (Four  
6-bit registers in total.)  
– {D5~D0}: These bits specify the wiper position of the  
respective XDCP. The Wiper Counter Register is  
loaded on power-up by the value in Data Register 0.  
The contents of the WCR can be loaded from any of  
the other Data Register or directly. The contents of  
the WCR can be saved in a DR.  
Data Registers  
The potentiometer has four nonvolatile Data Registers.  
These can be read or written directly by the host and  
data can be transferred between any of the four Data  
Registers and the Wiper Counter Register. It should be  
noted all operations changing data in one of these  
registers is a nonvolatile operation and will take a  
maximum of 10ms.  
If the application does not require storage of multiple  
settings for the potentiometer, these registers can be  
used as regular memory locations that could possibly  
store system parameters or user preference data.  
Characteristics subject to change without notice. 8 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
Instruction Format  
Notes: (1) “MACK”/”SACK”: stands for the acknowledge sent by the master/slave.  
(2) “A3 ~ A0”: stands for the device addresses sent by the master.  
(3) “X”: indicates that it is a “0” for testing purpose but physically it is a “don’t care” condition.  
(4) “I”: stands for the increment operation, SDA held high during active SCL phase (high).  
(5) “D”: stands for the decrement operation, SDA held low during active SCL phase (high).  
Read Wiper Counter Register (WCR)  
S device type  
device  
addresses  
instruction  
opcode  
wiper position  
(sent by slave on SDA)  
S
A
C
K
S
A
C
K
M S  
A T  
C O  
K P  
T
A
R
T
identifier  
W W W W W W  
0 0 P P P P P P  
A A  
A
0
0
1
0
1
0
1
0
0
1
0
0
0
0
3
2
5
4 3 2 1 0  
Write Wiper Counter Register (WCR)  
S device type  
device  
addresses  
instruction  
opcode  
wiper position  
(sent by master on SDA)  
S
A
C
K
S
A
C
K
S S  
A T  
C O  
K P  
T
A
R
T
identifier  
W W W W W W  
0 0 P P P P P P  
A A  
A
0
0
1
0
1
0
1
0
1
0
0
0
0
0
3
2
5
4 3 2 1 0  
Read Data Register (DR)  
S device type  
device  
addresses  
instruction  
opcode  
register  
addresses  
wiper position/data  
(sent by slave on SDA)  
S
A
C
K
S
A
C
K
M S  
A T  
C O  
K P  
T
A
R
T
identifier  
W W W W W W  
0 0 P P P P P P  
A A  
A
0
R R  
1 0  
0
1
0
1
0
1
0
1
1
0
0
3
2
5
4 3 2 1 0  
Write Data Register (DR)  
S device type  
device  
addresses  
instruction  
opcode  
register  
addresses  
wiper position/data  
(sent by master on SDA)  
S
S
A
C
K
S S  
T
A
R
T
identifier  
A
C
K
A T HIGH-VOLTAGE  
C O WRITE CYCLE  
K P  
W W W W W W  
0 0 P P P P P P  
5 4 3 2 1 0  
A A  
3 2  
A
0
R R  
0 0  
1 0  
0 1 0 1  
0
1 1 0 0  
XFR Data Register (DR) to Wiper Counter Register (WCR)  
S device type  
device  
addresses  
instruction  
opcode  
register  
addresses  
S
A
C
K
S S  
A T  
C O  
K P  
T
A
R
T
identifier  
A A  
3 2  
A
0
R R  
0 0  
1 0  
0 1 0 1  
0
1 1 0 1  
Characteristics subject to change without notice. 9 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
XFR Wiper Counter Register (WCR) to Data Register (DR)  
S device type  
device  
addresses  
instruction  
opcode  
register  
addresses  
S
A
C
K
S S  
T
A
R
T
identifier  
A T HIGH-VOLTAGE  
C O WRITE CYCLE  
K P  
A A  
3 2  
A
0
R R  
0 0  
1 0  
0 1 0 1  
0
1 1 1 0  
Increment/Decrement Wiper Counter Register (WCR)  
S
T
A
R
T
device type  
identifier  
device  
addresses  
instruction  
opcode  
increment/decrement  
(sent by master on SDA)  
A
S
A
C
K
S
S
T
O
P
C
K
A A  
A
0
I/ I/  
D D  
I/ I/  
D D  
0
1
0
1
0
0
0
1
0
0
0
0
0
.
.
.
.
3
2
SYMBOL TABLE  
Guidelines for Calculating Typical Values of Bus  
Pull-Up Resistors  
WAVEFORM  
INPUTS  
OUTPUTS  
120  
V
I
CC MAX  
OL MIN  
R
=
=1.8K  
MIN  
Must be  
steady  
Will be  
steady  
100  
80  
t
R
R
=
MAX  
C
BUS  
May change  
from Low to  
High  
Will change  
from Low to  
High  
Max.  
Resistance  
60  
40  
20  
0
May change  
from High to  
Low  
Will change  
from High to  
Low  
Min.  
Resistance  
Don’t Care:  
Changes  
Allowed  
Changing:  
State Not  
Known  
0
20 40 60 80 100 120  
N/A  
Center Line  
is High  
Impedance  
Bus Capacitance (pF)  
Characteristics subject to change without notice. 10 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
ABSOLUTE MAXIMUM RATINGS  
COMMENT  
Temperature under bias ....................–65°C to +135°C  
Storage temperature .........................–65°C to +150°C  
Voltage on SDA, SCL or any address  
Stresses above those listed under “Absolute Maximum  
Ratings” may cause permanent damage to the device.  
This is a stress rating only; functional operation of the  
device (at these or any other conditions above those  
listed in the operational sections of this specification) is  
not implied. Exposure to absolute maximum rating  
conditions for extended periods may affect device  
reliability.  
input with respect to V .........................–1V to +7V  
SS  
Voltage on V+ (referenced to V )......................... 10V  
SS  
Voltage on V- (referenced to V ).........................-10V  
SS  
(V+) – (V-).............................................................. 12V  
Any V /R ...............................................................V+  
H
H
Any V /R ................................................................. V-  
L
L
Lead temperature (soldering, 10 seconds)........ 300°C  
I
(10 seconds)................................................ 12mA  
W
RECOMMENDED OPERATING CONDITIONS  
Temperature  
Commercial  
Industrial  
Min.  
0°C  
Max.  
+70°C  
+85°C  
Device  
X9428  
Supply Voltage (V ) Limits  
CC  
5V 10%  
–40°C  
X9428-2.7  
2.7V to 5.5V  
ANALOG CHARACTERISTICS (Over recommended operating conditions unless otherwise stated.)  
Limits  
Symbol  
Parameter  
End to end resistance tolerance  
Power rating  
Min.  
Typ.  
Max.  
20  
Unit  
%
Test Conditions  
25°C, each pot  
50  
mW  
mA  
I
Wiper current  
6
W
R
Wiper resistance  
150  
40  
250  
100  
+5.5  
+5.5  
-4.5  
-2.7  
V+  
Wiper current = 1mA, V = 3V  
CC  
W
Wiper current = 1mA, V = 5V  
CC  
V+  
V-  
Voltage on V+ pin  
Voltage on V- pin  
X9428  
+4.5  
+2.7  
-5.5  
-5.5  
V-  
V
X9428-2.7  
X9428  
V
X9428-2.7  
V
Voltage on any V /R or V /R pin  
V
dBV  
%
TERM  
H
H
L
L
Noise  
Resolution (4)  
-140  
1.6  
Ref: 1kHz  
Absolute linearity (1)  
Relative linearity (2)  
1
MI(3)  
MI(3)  
ppm/°C  
V
—V  
w(n)(actual)  
w(n)(expected)  
]
0.2  
V
—[V  
w(n) + MI  
w(n + 1)  
Temperature Coefficient of R  
300  
TOTAL  
Ratiometric Temperature Coefficient  
Potentiometer Capacitances  
20 ppm/°C  
pF  
C /C /C  
W
10/10/25  
See Circuit #3,  
Spice Macromodel  
H
L
Characteristics subject to change without notice. 11 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
D.C. OPERATING CHARACTERISTICS (Over the recommended operating conditions unless otherwise specified.)  
Limits  
Symbol  
Parameter  
Min.  
Typ.  
Max.  
Unit  
Test Conditions  
I
V
supply current  
1
mA  
f = 400kHz, SDA = Open,  
SCL  
Other Inputs = V  
SS  
CC1  
CC  
(nonvolatile write)  
I
V
supply current  
100  
µA  
f
= 400kHz, SDA = Open,  
SCL  
CC2  
CC  
(move wiper, write, read)  
Other Inputs = V  
SS  
I
V
current (standby)  
1
µA  
µA  
µA  
V
SCL = SDA = V , Addr. = V  
CC SS  
SB  
CC  
I
Input leakage current  
Output leakage current  
Input HIGH voltage  
Input LOW voltage  
Output LOW voltage  
10  
10  
V
V
= V to V  
SS CC  
LI  
IN  
I
= V to V  
SS CC  
LO  
OUT  
V
V
x 0.7  
V
V
x 0.5  
IH  
CC  
CC  
V
–0.5  
x 0.1  
V
IL  
CC  
V
0.4  
V
I
= 3mA  
OL  
OL  
Notes: (1) Absolute linearity is utilized to determine actual wiper voltage versus expected voltage as determined by wiper position when used  
as a potentiometer.  
(2) Relative linearity is utilized to determine the actual change in voltage between two successive tap positions when used as a potenti-  
ometer. It is a measure of the error in step size.  
(3) MI = RTOT/63 or (R —R )/63, single pot  
H
L
(4) Max. = all four arrays cascaded together, Typical = individual array resolutions.  
ENDURANCE AND DATA RETENTION  
Parameter  
Minimum endurance  
Data retention  
Min.  
100,000  
100  
Unit  
Data changes per bit per register  
Years  
CAPACITANCE  
Symbol  
Test  
Max.  
Unit  
pF  
Test Conditions  
(5)  
C
Input/output capacitance (SDA)  
8
6
V
= 0V  
= 0V  
I/O  
I/O  
(5)  
C
Input capacitance (A0, A1, A2, A3, and SCL)  
pF  
V
IN  
IN  
POWER-UP TIMING  
Symbol  
Parameter  
Min.  
Typ.  
Max.  
1
Unit  
(6)  
t
Power-up to initiation of read operation  
Power-up to initiation of write operation  
ms  
ms  
PUR  
(6)  
t
5
PUW  
(7)  
t V  
V
Power up ramp rate  
0.2  
50  
V/msec  
R CC  
CC  
POWER-UP AND POWER-DOWN  
There are no restrictions on the power-up or power-down sequencing of the bias supplies V , V+, and V- provided  
CC  
that all three supplies reach their final values within 1msec of each other. However, at all times, the voltages on the  
potentiometer pins must be less than V+ and more than V–. The recall of the wiper position from nonvolatile  
memory is not in effect until all supplies reach their final value.  
Notes: (5) This parameter is periodically sampled and not 100% tested  
(6) t  
and t  
are the delays required from the time the third (last) power supply (V , V+ or V-) is stable until the specific  
PUR  
PUW CC  
instruction can be issued.These parameters are periodically sampled and not 100% tested.  
(7) Sample tested only.  
Characteristics subject to change without notice. 12 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
A.C. TEST CONDITIONS  
Circuit #3 SPICE Macro Model  
Input pulse levels  
V
x 0.1 to V x 0.9  
CC  
CC  
R
TOTAL  
Input rise and fall times  
Input and output timing level  
10ns  
R
R
L
H
C
V
x 0.5  
L
CC  
C
H
C
W
10pF  
EQUIVALENT A.C. LOAD CIRCUIT  
10pF  
25pF  
5V  
2.7V  
R
W
1533Ω  
SDA Output  
100pF  
100pF  
AC TIMING (over recommended operating conditions)  
Symbol Parameter  
Min.  
100  
2500  
600  
1300  
600  
600  
600  
100  
30  
Max.  
Unit  
kHz  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
f
Clock frequency  
400  
SCL  
t
Clock cycle time  
CYC  
t
Clock high time  
HIGH  
t
Clock low time  
LOW  
t
Start setup time  
SU:STA  
HD:STA  
SU:STO  
t
Start hold time  
t
Stop setup time  
t
SDA data input setup time  
SDA data input hold time  
SCL and SDA rise time  
SCL and SDA fall time  
SU:DAT  
HD:DAT  
t
t
300  
300  
900  
R
t
F
t
SCL low to SDA data output valid time  
SDA data output hold time  
AA  
t
50  
50  
1300  
0
DH  
T
Noise suppression time constant at SCL and SDA inputs  
Bus free time (prior to any transmission)  
WP, A0, A1, A2 and A3 setup time  
I
t
BUF  
t
SU:WPA  
HD:WPA  
t
WP, A0, A1, A2 and A3 hold time  
0
Characteristics subject to change without notice. 13 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
HIGH-VOLTAGE WRITE CYCLE TIMING  
Symbol  
Parameter  
Typ.  
Max.  
Unit  
t
High-voltage write cycle time (store instructions)  
5
10  
ms  
WR  
XDCP TIMING  
Symbol  
Parameter  
Min. Max. Unit  
t
Wiper response time after the third (last) power supply is stable  
Wiper response time after instruction issued (all load instructions)  
10  
10  
10  
µs  
µs  
µs  
WRPO  
t
WRL  
t
Wiper response time from an active SCL/SCK edge (increment/decrement instruction)  
WRID  
Note: (8) A device must internally provide a hold time of at least 300ns for the SDA signal in order to bridge the undefined region of the falling  
edge of SCL.  
TIMING DIAGRAMS  
START and STOP Timing  
(START)  
(STOP)  
t
t
F
R
SCL  
SDA  
t
t
t
SU:STO  
SU:STA  
HD:STA  
t
t
F
R
Input Timing  
t
t
CYC  
HIGH  
SCL  
SDA  
t
LOW  
t
t
t
BUF  
SU:DAT  
HD:DAT  
Output Timing  
SCL  
SDA  
t
t
DH  
AA  
Characteristics subject to change without notice. 14 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
XDCP Timing (for All Load Instructions)  
(STOP)  
SCL  
SDA  
LSB  
t
WRL  
V
/R  
W
W
XDCP Timing (for Increment/Decrement Instruction)  
SCL  
Wiper Register Address  
Inc/Dec  
Inc/Dec  
SDA  
t
WRID  
V
/R  
W
W
Write Protect and Device Address Pins Timing  
(START)  
(STOP)  
SCL  
...  
(Any Instruction)  
...  
SDA  
...  
t
t
SU:WPA  
HD:WPA  
WP  
A0, A2, A3  
Characteristics subject to change without notice. 15 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
APPLICATIONS INFORMATION  
Basic Configurations of Electronic Potentiometers  
+V  
R
V
R
V
/R  
W
W
I
Three terminal Potentiometer;  
Variable voltage divider  
Two terminal Variable Resistor;  
Variable current  
Application Circuits  
Noninverting Amplifier  
Voltage Regulator  
V
+
S
V
V
V (REG)  
O
317  
O
IN  
R
1
R
2
I
adj  
R
R
1
2
V
= (1+R /R )V  
V
(REG) = 1.25V (1+R /R )+I  
R
adj  
O
2
1
S
O
2
1
2
Offset Voltage Adjustment  
Comparator with Hysteresis  
R
R
2
1
V
+
S
V
V
S
O
100KΩ  
+
V
O
TL072  
R
R
1
2
10KΩ  
10KΩ  
+12V  
V
V
= {R /(R +R )} V (max)  
1 1 2 O  
UL  
LL  
10KΩ  
-12V  
= {R /(R +R )} V (min)  
1
1
2
O
Characteristics subject to change without notice. 16 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
Application Circuits (continued)  
Attenuator  
Filter  
C
V
+
S
R
V
R
1
2
O
R
V
O
V
+
S
R
3
R
2
R
4
All R = 10kΩ  
S
R
1
G
= 1 + R /R  
2 1  
V
= G V  
S
O
O
fc = 1/(2pRC)  
-1/2 G +1/2  
Inverting Amplifier  
Equivalent L-R Circuit  
R
R
2
1
V
S
R
2
C
1
+
V
+
S
V
O
R
R
1
3
Z
IN  
V = G V  
O
S
G = - R /R  
2
1
Z
= R + s R (R + R ) C = R + s Leq  
2 2 1 3 1 2  
IN  
(R + R ) >> R  
1
3
2
Function Generator  
C
R
R
1
2
+
+
R
R
}
}
A
B
frequency R , R , C  
1
2
amplitude R , R  
A
B
Characteristics subject to change without notice. 17 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
PACKAGING INFORMATION  
14-Lead Plastic, TSSOP, Package Type V  
.025 (.65) BSC  
.169 (4.3)  
.177 (4.5)  
.252 (6.4) BSC  
.193 (4.9)  
.200 (5.1)  
.047 (1.20)  
.0075 (.19)  
.0118 (.30)  
.002 (.05)  
.006 (.15)  
.010 (.25)  
Gage Plane  
0° - 8°  
Seating Plane  
.019 (.50)  
.029 (.75)  
Detail A (20X)  
.031 (.80)  
.041 (1.05)  
See Detail “A”  
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)  
Characteristics subject to change without notice. 18 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
PACKAGING INFORMATION  
16-Lead Plastic SOIC (300 Mil Body) Package Type S  
0.290 (7.37)  
0.299 (7.60)  
0.393 (10.00)  
0.420 (10.65)  
PIN 1 INDEX  
PIN 1  
0.014 (0.35)  
0.020 (0.51)  
0.403 (10.2 )  
0.413 ( 10.5)  
(4X) 7°  
0.092 (2.35)  
0.105 (2.65)  
0.003 (0.10)  
0.012 (0.30)  
0.050 (1.27)  
0.010 (0.25)  
0.020 (0.50)  
0.050" Typical  
X 45°  
0° – 8°  
0.050"  
Typical  
0.0075 (0.19)  
0.010 (0.25)  
0.420"  
0.015 (0.40)  
0.050 (1.27)  
0.030" Typical  
16 Places  
FOOTPRINT  
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)  
Characteristics subject to change without notice. 19 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  
X9428  
Ordering Information  
X9428  
Y
P
T
V
V
Limits  
CC  
Device  
Blank = 5V 10%  
–2.7 = 2.7 to 5.5V  
Temperature Range  
Blank = Commercial = 0°C to +70°C  
I = Industrial = –40°C to +85°C  
Package  
P = 16-Lead Plastic DIP*  
S = 16-Lead SOIC  
V = 14-Lead TSSOP  
Potentiometer Organization  
Y =  
W =  
2KΩ  
10KΩ  
*Note: P package only available as X9428WP16I-2.7 for prototyping. Other resistor values not available in package.  
©Xicor, Inc. 2000 Patents Pending  
LIMITED WARRANTY  
Devices sold by Xicor, Inc. are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. Xicor, Inc. makes no warranty,  
express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement.  
Xicor, Inc. makes no warranty of merchantability or fitness for any purpose. Xicor, Inc. reserves the right to discontinue production and change specifications and prices  
at any time and without notice.  
Xicor, Inc. assumes no responsibility for the use of any circuitry other than circuitry embodied in a Xicor, Inc. product. No other circuits, patents, or licenses are implied.  
TRADEMARK DISCLAIMER:  
Xicor and the Xicor logo are registered trademarks of Xicor, Inc. AutoStore, Direct Write, Block Lock, SerialFlash, MPS, and XDCP are also trademarks of Xicor, Inc. All  
others belong to their respective owners.  
U.S. PATENTS  
Xicor products are covered by one or more of the following U.S. Patents: 4,326,134; 4,393,481; 4,404,475; 4,450,402; 4,486,769; 4,488,060; 4,520,461; 4,533,846;  
4,599,706; 4,617,652; 4,668,932; 4,752,912; 4,829,482; 4,874,967; 4,883,976; 4,980,859; 5,012,132; 5,003,197; 5,023,694; 5,084,667; 5,153,880; 5,153,691;  
5,161,137; 5,219,774; 5,270,927; 5,324,676; 5,434,396; 5,544,103; 5,587,573; 5,835,409; 5,977,585. Foreign patents and additional patents pending.  
LIFE RELATED POLICY  
In situations where semiconductor component failure may endanger life, system designers using this product should design the system with appropriate error detection  
and correction, redundancy and back-up features to prevent such an occurrence.  
Xicor’s products are not authorized for use in critical components in life support devices or systems.  
1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to  
perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user.  
2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life  
support device or system, or to affect its safety or effectiveness.  
Characteristics subject to change without notice. 20 of 20  
REV 1.1.5 7/8/03  
www.xicor.com  

相关型号:

X9428WS16

Single Digitally Controlled Potentiometer
INTERSIL

X9428WS16-2.7

Single Digitally Controlled Potentiometer
INTERSIL

X9428WS16I

Single Digitally Controlled Potentiometer
INTERSIL

X9428WS16I-2.7

Single Digitally Controlled Potentiometer
INTERSIL

X9428WS16IZ

Single Digitally Controlled Potentiometer
INTERSIL

X9428WS16IZ-2.7

Single Digitally Controlled Potentiometer
INTERSIL

X9428WS16IZ-2.7T1

10K DIGITAL POTENTIOMETER, 2-WIRE SERIAL CONTROL INTERFACE, 64 POSITIONS, PDSO16, 0.300 INCH, ROHS COMPLIANT, PLASTIC, MS-013AA, SOIC-16
RENESAS

X9428WS16Z

Single Digitally Controlled Potentiometer
INTERSIL

X9428WS16Z-2.7

Single Digitally Controlled Potentiometer
INTERSIL

X9428WS16Z-2.7T1

10K DIGITAL POTENTIOMETER, 2-WIRE SERIAL CONTROL INTERFACE, 64 POSITIONS, PDSO16, 0.300 INCH, ROHS COMPLIANT, PLASTIC, MS-013AA, SOIC-16
RENESAS

X9428WS16ZT1

10K DIGITAL POTENTIOMETER, 2-WIRE SERIAL CONTROL INTERFACE, 64 POSITIONS, PDSO16, 0.300 INCH, ROHS COMPLIANT, PLASTIC, MS-013AA, SOIC-16
RENESAS

X9428WSI

Single Digitally Controlled Potentiometer
INTERSIL