LTC1555L-1.8_技术文档

LTC1555L-1.8

SIM Power Supply and

Level Translator

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FEATURES

DESCRIPTIO

The LTC^®1555L-1.8 provides power conversion and level

shifting needed for low voltage GSM and WCDMA cellular

telephones to interface with either 1.8V, 3V or 5V sub-

scriber identity modules (SIMs). The part contains a

patented buck/boost charge pump DC/DC converter* that

delivers a regulated V_CCsupply voltage to the SIM card.

Input voltage may range from 2.6V to 6V allowing direct

connection to the battery. The output voltage may be

programmed to 1.8V, 3V, 5V or direct connection to the

V_INpin.

■

Buck/Boost Charge Pump Generates 1.8V, 3V or 5V

■

Input Voltage Range: 2.6V to 6V

■

Controller V_CCRange: 1.425V to 4.4V

>10kV ESD on All SIM Contact Pins

■

Short-Circuit and Overtemperature Protected

■

Meets all ETSI and IMT-2000 SIM Interface

Requirements

■

1.8V to 5V Signal Level Translators

■

Very Low Operating Current: 32µA

■

Very Low Shutdown Current: <1µA

■

Soft-Start Limits Inrush Current at Turn-On

Internal level translators allow controllers operating with

supplies as low as 1.425V to interface with 1.8V, 3V and

5V SIMs. A soft-start feature limits inrush current at turn-

on, mitigating start-up problems that may result when the

input is supplied by another low-power DC/DC converter.

Battery life is maximized by 32µA operating current, and

1µA shutdown current. Board area is minimized by the

miniature 16-pin narrow SSOP packages and the need for

only three small external capacitors.

■

1MHz Switching Frequency

■

Available in 16-Pin Narrow SSOP Package

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APPLICATIO S

■

SIM Interface in GSM Cellular Telephones

WCDMA SIM Interface

Smart Card Readers

■

, LTC and LT are registered trademarks of Linear Technology Corporation.

*U.S. Patent No.: 5,973,944

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TYPICAL APPLICATIO

GSM Cellular Telephone SIM Interface

GSM

CONTROLLER

V

IN

2.6V TO 6V

1.425V TO 4.4V

LTC1555L-1.8

SIM

1

16

15

14

13

12

11

10

9

CIN

CLK

RST

I/O

CLK

RST

I/O

2

3

4

5

6

7

8

RIN

DATA

DDRV

V

VCC

= 1.8V,3V,5V

CC

I

= 10mA

V

DV

CC

V

CC

IN

+

2.2µF

M2

M1

M0

C1

0.1µF

–

1µF

GND

1555L TA01

1

LTC1555L-1.8

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ABSOLUTE AXI U RATI GS

PACKAGE/ORDER I FOR ATIO

(Note 1)

ORDER PART

V_IN, DV_CCto GND .....................................–0.3V to 6.5V

V_CCto GND ...............................................–0.3V to 6.5V

Digital Inputs to GND................................–0.3V to 6.5V

CLK, RST, I/O to GND ..................... –0.3V to V_CC+ 0.3V

V_CCShort-Circuit Duration............................... Indefinite

Operating Temperature Range (Note 2) .. – 40°C to 85°C

Storage Temperature Range ................. – 65°C to 150°C

Lead Temperature (Soldering,10 sec)................... 300°C

TOP VIEW

NUMBER

CIN

RIN

1

2

3

4

5

6

7

8

16 CLK

15 RST

LTC1555LEGN-1.8

DATA

DDRV

14

13

12

11

10

9

I/0

V

CC

DV

CC

V

IN

+

M2

M1

M0

C1

–

GN PART MARKING

555L18

GND

GN PACKAGE

16-LEAD PLASTIC SSOP

T_JMAX= 125°C, θ_JA= 150°C/W

Consult factory for parts specified with wider operating temperature ranges.

ELECTRICAL CHARACTERISTICS

The ● denotes the specifications which apply over the full operating

temperature range, otherwise specifications are at T_A= 25°C. (V_IN= 2.6V to 6V, DV_CC= 1.425V to 4.4V, controller digital pins tied to

DV_CC, SIM digital pins floating, C1 = 0.1µF, C_OUT= 2.2µF unless otherwise noted)

PARAMETER

Operating Voltage

CONDITIONS

MIN

2.6

TYP

MAX

6

UNITS

V

●

IN

DV Operating Voltage

CC

1.425

4.4

V

DV Undervoltage Lockout

1.2

27

V

CC

V

Operating Current

Shutdown Current

V

= 3V, I = 0V

VCC

●

65

1

µA

IN

CC

M0, M1 = 0V

M0, M1, DATA = DV , C = 1MHz

DV Operating Current

CC

5

30

1

CC IN

DV Shutdown Current

CC

M0, M1 = 0V, DATA, C = DV

IN CC

V

Output Voltage

0 < I

< 10mA

VCC

CC

M0, M1 = DV , 2.6V < V < 6V

M0, M1 = DV , 2.7V < V < 6V

M0 = DV , M1 = 0

M0 = 0, M1 = DV

M0 = DV , M1 = 0, M2 = DV , 0 ≤ I ≤ 6mA

M0 = DV , M1 = 0, M2 = DV , V ≥ 3V, I

●

4.55

4.75

2.8

5

3

5.25

3.2

V

CC

IN

CC

IN

CC

V

– 0.2

V

IN

CC

IN

1.71

1.8

1.89

CC

VCC

≤ 10mA

CC

CC IN

VCC

V

Short-Circuit Current

V

Shorted to GND

CC

●

50

1

150

mA

CC

Charge Pump f

MHz

OSC

2

LTC1555L-1.8

ELECTRICAL CHARACTERISTICS

The ● denotes the specifications which apply over the full operating

temperature range, otherwise specifications are at T_A= 25°C. (V_IN= 2.6V to 6V, DV_CC= 1.425V to 4.4V, controller digital pins tied to

DV_CC, SIM digital pins floating, C1 = 0.1µF, C_OUT= 2.2µF unless otherwise noted)

PARAMETER

Controller Inputs/Outputs (DV = 1.8V)

CONDITIONS

MIN

TYP

MAX

UNITS

CC

Input Current (I /I )

M0, M1, M2, RIN, CIN

●

–100

–5

100

nA

µA

IH IL

Input Current (I /I )

DDRV

DATA

5

20

IH IL

High Level Input Current (I )

–20

µA

IH

Low Level Input Current (I )

1

mA

IL

High Input Voltage Threshold (V )

M0, M1, M2, RIN, CIN, DDRV

DATA

●

0.7 × DV

V

IH

CC

DV – 0.6

CC

Low Input Voltage Threshold (V )

M0, M1, M2, RIN, CIN, DDRV

DATA

●

0.2 × DV

V

IL

CC

0.4

High Level Output Voltage (V

)

DATA Source Current = 20µA I/O = V

●

0.7 × DV

V

OH

CC

Low Level Output Voltage (V

DATA Pull-Up Resistance

DATA Output Rise/Fall Time

)

DATA Sink Current = –200µA I/O = 0V (Note 3)

Between DATA and DV

0.4

30

2

OL

13

20

kΩ

µs

CC

DATA Loaded with 30pF

1.3

SIM Inputs/Outputs (V = 3V or 5V)

CC

I/O High Input Voltage Threshold (V )

I

= ±20µA

●

0.7 × V

CC

V

IH

IH(MAX)

IL(MAX)

I/O Low Input Voltage Threshold (V )

= 1mA

0.4

IL

High Level Output Voltage (V

)

I/O, Source Current = 20µA DATA or DDRV = DV

0.8 × V

0.9 × V

6.5

V

OH

CC

Low Level Output Voltage (V

)

OL

I/O, Sink Current = –1mA DATA or DDRV = 0V (Note 3)

RST, CLK Source Current = 20µA

0.4

V

High Level Output Voltage (V

)

V

OH

CC

Low Level Output Voltage (V

I/O Pull-Up Resistance

)

OL

RST, CLK Sink Current = –200µA

0.4

14

V

Between I/O and V

10

kΩ

CC

SIM Inputs/Outputs (V = 1.8V)

CC

I/O High Input Voltage Threshold (V )

I

= ±20µA

●

0.7 × V

CC

V

IH

IH(MAX)

IL(MAX)

I/O Low Input Voltage Threshold (V )

= 1mA

0.2 × V

0.8 × V

IL

CC

High Level Output Voltage (V

)

I/O, Source Current = 20µA DATA or DDRV = DV

CC

OH

Low Level Output Voltage (V

)

OL

I/O, Sink Current = –200µA DATA or DDRV = 0V (Note 3)

RST, CLK Source Current = 20µA

0.4

High Level Output Voltage (V

)

0.9 × V

OH

CC

Low Level Output Voltage (V

)

OL

RST, CLK Sink Current = –200µA

0.2 × V

CC

SIM Timing Parameters (DV = 1.8V, V = 5V)

CC

CLK Rise/Fall Time

CLK Loaded with 30pF, V = 3V or 5V

●

18

50

ns

CC

V

= 1.8V

CC

RST, I/O Rise/Fall Time

CLK Frequency

RST, I/O Loaded with 30pF

CLK Loaded with 30pF

●

1

5

µs

MHz

ms

V

Turn-On Time

C

= 2.2µF, I = 0

VCC

0.5

CC

OUT

Discharge Time to 1V

I

= 0, V = 5V, C = 2.2µF

OUT

ms

VCC

CC

operating temperature range are assured by design, characterization and

correlation with statistical process controls.

Note 1: Absolute Maximum Ratings are those values beyond which the life

of a device may be impaired.

Note 3: The DATA and I/O pull-down drivers must also sink current

sourced by the internal pull-up resistor.

Note 2: The LTC1555LEGN-1.8 is guaranteed to meet performance

specifications from 0°C to 70°C. Specifications over the –40°C to 85°C

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LTC1555L-1.8

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TYPICAL PERFOR A CE CHARACTERISTICS

I_VINvs Temperature

I_DVCCvs V_DVCC

I_VINvs V_IN

50

40

30

20

10

50

40

30

20

10

20

15

10

5

I

T

= 0mA

= 25°C

V

= 3.6V

= 0mA

F

= 1MHz

VCC

A

IN

CLK

I

VCC

V

= 5V

CC

V

CC

= 5V

T

= 85°C

A

= 3V

CC

V

= 3V

CC

V

= 1.8V

T = –40°C

A

CC

V

CC

= 1.8V

T

= 25°C

A

0

4

5

40

2

6

–40

80

120

3

0

1

4

5

2

V

IN

(V)

TEMPERATURE (°C)

V

(V)

DVCC

1555L • G01

1555L • G02

1555L • G03

V_CCvs V_IN

6.0

5.5

5.0

4.5

4.0

2.2

2.0

1.8

1.6

1.4

3.6

3.3

3.0

2.7

2.4

V

I

= 5V

= 10mA

V

I

= 3V

= 10mA

V

I

= 1.8V

= 10mA

CC

VCC

CC

VCC

CC

VCC

T

= 25°C

A

T

= 85°C

A

T

= 85°C

A

T

= –40°C

A

= –40°C

A

T

= –40°C

T

= 25°C

A

5

A

T

= 25°C

A

T

= 85°C

A

4

2

6

4

2

5

6

3

2

5

6

3

V

(V)

V

(V)

IN

V

IN

(V)

IN

1555L • G04

1555L • G06

1555L • G05

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PIN FUNCTIONS

CIN (Pin 1): Clock Input Pin from Controller.

DDRV (Pin 4): Optional Data Input Pin for Sending Data to

the SIM Card. When not needed, the DDRV pin should

either be left floating or tied to DV_CC(an internal 1µA

current source will pull the DDRV pin up to DV_CCif left

floating).

RIN (Pin 2): Reset Input Pin from Controller.

DATA (Pin 3): Controller Side Data Input/Output Pin. Can

be used for single pin bidirectional data transfer between

the controller and the SIM card as long as the controller

data pin is open drain. The controller output must be able

to sink 1mA max when driving the DATA pin low due to the

internal pull-up resistors on the DATA and I/O pins. If the

controllerdataoutputisnotopendrain, thentheDDRVpin

should be used for sending data to the SIM card and the

DATA pin used for receiving data from the SIM card.

DV_CC(Pin 5): Supply Voltage for Controller Side Digital

Input/Output Pins (typically 3V). May be between 1.425V

and 4.4V. The DV_CCsupply may be powered-down in

shutdown for further reduction in battery current. When

DV_CCdrops below 1.2V, the charge pump is disabled and

the LTC1555L-1.8 goes into shutdown mode regardless

of the signals on the M0-M2 pins.

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LTC1555L-1.8

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PIN FUNCTIONS

M2 (Pin 6): Mode Control Bit 2 (see Table 1). (Pin 6 was

V_IN(Pin12):ChargePumpInputPin.Maybebetween2.6V

and 6V. There is no power-up sequencing requirement for

V_INwith respect to DV_CC.

previously used for soft-start control on the LTC1555.)

M1 (Pin 7): Mode Control Bit 1 (see Table 1).

M0 (Pin 8): Mode Control Bit 0 (see Table 1).

V_CC(Pin 13): SIM Card V_CCOutput. Should be connected

to the SIM V_CCcontact. The V_CCoutput voltage is deter-

mined by the M0-M2 pins (see Table 1). V_CCis discharged

to GND during shutdown (M0, M1 = 0V). A 2.2µF low ESR

ouptut capacitor should connect close to the V_CCpin.

GND (Pin 9): Ground for Both the SIM and the Controller.

Should be connected to the SIM GND contact as well as to

the V_IN/controller GND. Proper grounding and supply

bypassing is required to meet 10kV ESD specifications.

C1^–(Pin10):ChargePumpFlyingCapacitorNegative Input.

C1⁺(Pin11):ChargePumpFlyingCapacitorPositive Input.

I/O (Pin 14): SIM Side I/O Pin. The pin is an open drain

output with a nominal pull-up resistance of 10kΩ and

should be connected to the SIM I/O contact. The SIM card

must sink up to 1mA max when driving the I/O pin low due

to the internal pull-up resistors on the I/O and DATA pins.

The I/O pin is held active low during shutdown.

Table 1. Truth Table

M0

0V

M1

M2

0V or DV

0V

OPERATING MODE

Shutdown (V = 0V)

0V

CC

RST (Pin 15): Level Shifted Reset Output Pin. Should be

connected to the SIM RST contact.

DV

CC

V = V

CC IN

DV

0V

V

= 3V

CC

CLK (Pin 16): Level Shifted Clock Output Pin. Should be

connected to the SIM CLK contact. Careful trace routing is

recommended due to fast rise and fall edge speeds.

DV

CC

V

CC

= 1.8V

DV

CC

0V or DV

V = 5V

CC

W

BLOCK DIAGRA

V

BATT

0.1µF

C

IN

1µF

+

–

C1

LTC1555L-1.8

V

CC

IN

V

CC

C

OUT

2.2µF

M0

M1

M2

STEP-UP/

STEP-DOWN

CHARGE PUMP

DC/DC

CONVERTER

1.8V

UVLO

DV

CC

V

CC

RIN

RST

CLK

RST

CLK

CONTROLLER

SIM

CIN

20k

10k

DATA

DDRV

I/O

1µA

OPTIONAL

GND

1555L BD

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LTC1555L-1.8

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APPLICATIO S I FOR ATIO

The LTC1555L-1.8 performs the two primary functions

necessary for low voltage controllers (e.g., GSM cellular

telephone controllers, smart card readers, etc.) to com-

municate with 5V SIMs or smart cards. The part produces

aregulated1.8V, 3Vor5VV_CCsupplyfortheSIM, andalso

provides level translators for communication between the

SIM and the controller.

Iftheinputsourceimpedanceisverylow(<0.5Ω),C_INmay

notbeneeded.IncreasingthesizeofC_OUTto2.2µForgreater

willreduceoutputvoltageripple—particularlywithhighV_IN

voltages (4V or greater). A ceramic capacitor is recom-

mended for the flying capacitor C1 with a value of 0.1µF or

0.22µF.

Output Ripple

V

_CCVoltage Regulator

Normal LTC1555L-1.8 operation produces voltage ripple

on the V_CCpin. Output voltage ripple is required for the

parts to regulate. Low frequency ripple exists due to the

hysteresis in the sense comparator and propagation de-

lays in the charge pump enable/disable circuits. High

frequency ripple is also present mainly from the ESR

(equivalent series resistance) in the output capacitor.

Typical output ripple (V_IN< 4V) under maximum load is

75mV peak-to-peak with a low ESR, 2.2µF output capaci-

tor (V_CC= 5V).

The regulator section of the LTC1555L-1.8 (refer to Block

Diagram) consists of a buck/boost charge pump DC/DC

converter. Thechargepumpcanoperateoverawideinput

voltage range (2.6V to 6V) while maintaining a regulated

V_CCoutput. The wide V_INrange enables the part to be

powered directly from a battery (if desired) rather than

from a DC/DC converter output. When V_INis less than the

selected V_CCvoltage, the part operates as a switched

capacitor voltage doubler. When V_INis greater than V_CC,

thepartoperatesasgatedswitchstep-down converter. In

either case, voltage conversion requires only one small

flying capacitor and output capacitor.

The magnitude of the ripple voltage depends on several

factors. High input voltages increase the output ripple

since more charge is delivered to C_OUTper charging cycle.

A large C1 flying capacitor (> 0.22µF) also increases ripple

instep-upmodeforthesamereason.Largeoutputcurrent

load and/or a small output capacitor (< 1µF) results in

higher ripple due to higher output voltage dV/dt. High ESR

capacitors (ESR > 0.5Ω) on the output pin cause high

frequency voltage spikes on V_OUTwith every clock cycle.

The V_CCoutput can be programmed via the M0-M2 pins to

either 1.8V, 3V, 5V or direct connection to V_IN. This

flexibility is useful in applications where multiple voltage

SIMs may be used. When the charge pump is put into

shutdown (M0, M1 = 0), V_CCis pulled to GND via an

internalswitchtoaidinpropersystemsupplysequencing.

An internal soft-start feature helps to limit inrush currents

upon start-up or when coming out of shutdown mode.

Inrush current limiting is especially useful when powering

the LTC1555L-1.8 from a DC/DC output since the unlim-

ited inrush current may approach 300mA and cause

voltagetransientsonthe3Vsupply. Thepartisfullyshort-

circuitandovertemperatureprotected, andcansurvivean

indefinite short from V_CCto GND.

A 2.2µF ceramic capacitor on the V_CCpin should produce

acceptable levels of output voltage ripple in nearly all

applications. Also, in order to keep noise down all capaci-

tors should be placed close to LTC1555L-1.8.

Level Translators

All SIMs and smart cards contain a clock input, a reset

input, and a bidirectional data input/output. The

LTC1555L-1.8 provides level translators to allow

controllers to communicate with the SIM. (See Figure 1a

and 1b). The CLK and RST inputs to the SIM are level

shifted from the controller supply rails (DV_CCand GND) to

the SIM supply rails (V_CCand GND). The data input to the

SIMmaybeprovidedtwodifferentways. Thefirstmethod

is to use the DATA pin as a bidirectional level translator.

Capacitor Selection

For best performance, it is recommended that low ESR

(<0.5Ω)capacitorsbeusedforbothC_INandC_OUTtoreduce

noise and ripple. The C_INand C_OUTcapacitors should be

either ceramic or tantalum and should be 1µF or greater

(ceramiccapacitorswillproducethesmallestoutputripple).

6

LTC1555L-1.8

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APPLICATIO S I FOR ATIO

This configuration is only allowed if the controller data

output pin is open drain (all SIM I/O pins are open drain).

Internal pull-up resistors are provided for both the DATA

pin and the I/O pin on the SIM side. The second method

is to use the DDRV pin to send data to the SIM and use the

DATA pin to receive data from the SIM. When the DDRV

pin is not used, it should either be left floating or tied to

DV_CC.

is forced below 1.2V, an undervoltage lockout circuit

forces the LTC1555L-1.8 into shutdown mode regardless

of the status of the M0-M2 pins.

10kV ESD Protection

All pins that connect to the SIM (CLK, RST, I/O, V_CC, GND)

withstand over 10kV of human body model ESD. In order

to ensure proper ESD protection, careful board layout is

required. The GND pin should be tied directly to a GND

plane. The V_CCcapacitor should be located very close to

the V_CCpin and tied immediately to the GND plane.

Shutting Down the DV_CCSupply

To conserve power, the DV_CCsupply may be shut down

while the V_INsupply is still active. When the DV_CCsupply

LTC1555L-1.8

CLK TO SIM

RST TO SIM

CIN

CLK

RST

I/O

CLK TO SIM

RST TO SIM

CIN

CLK

RST

I/O

RIN

DATA FROM SIM

DATA TO SIM

DATA

DDRV

DATA TO/FROM SIM

DATA

DDRV

V

CC

CONTROLLER

SIDE

DV

CC

CONTROLLER

SIDE

DV

CC

SIM SIDE

1555L F01b

1555L F01a

Figure 1a. Level Translator Connections for

Bidirectional Controller DATA Pin

Figure 1b. Level Translator Connections for

One-Directional Controller Side DATA Flow

7

LTC1555L-1.8

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TYPICAL APPLICATIO

WCDMA Cellular Telephone SIM Interface

WCDMA

CONTROLLER

V

IN

2.6V TO 6V

1.425V TO 4.4V

LTC1555L-1.8

SIM

1

16

15

14

13

12

11

10

9

CIN

CLK

RST

I/O

CLK

RST

I/O

2

3

4

5

6

7

8

RIN

DATA

DDRV

V

VCC

= 1.8V,3V

CC

I

= 6mA

V

DV

CC

V

CC

IN

+

2.2µF

M2

M1

M0

C1

0.1µF

–

1µF

GND

1555L TA02

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PACKAGE DESCRIPTIO

Dimensions in inches (millimeters) unless otherwise noted.

GN Package

16-Lead Plastic SSOP (Narrow 0.150)

(LTC DWG # 05-08-1641)

0.189 – 0.196*

(4.801 – 4.978)

0.009

(0.229)

REF

16 15 14 13 12 11 10 9

0.229 – 0.244

(5.817 – 6.198)

0.150 – 0.157**

(3.810 – 3.988)

1

2

3

4

5

6

7

8

0.015 ± 0.004

(0.38 ± 0.10)

× 45°

0.053 – 0.068

(1.351 – 1.727)

0.004 – 0.0098

(0.102 – 0.249)

0.007 – 0.0098

(0.178 – 0.249)

0° – 8° TYP

0.016 – 0.050

(0.406 – 1.270)

0.0250

(0.635)

BSC

0.008 – 0.012

(0.203 – 0.305)

* DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH

SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE

** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD

FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE

GN16 (SSOP) 1098

RELATED PARTS

PART NUMBER

LTC1555/LTC1556

LTC1555L

DESCRIPTION

COMMENTS

SIM Power Supply and Level Translator

Smart Card Interface

V

= 2.7V to 10V; Step-Up/-Down Charge Pump

IN

= 2.6V to 6V; Step-Up/-Down Charge Pump; DV as low as 1.425V

CC

LTC1755

= 2.7V to 6V; 24-Pin SSOP Package; I = 60µA

Q

LTC1756

Smart Card Interface

= 2.7V to 6V; 16-Pin SSOP Package; I = 75µA

Q

LTC1986

3V/5V SIM Power Supply in SOT-23

= 2.6V to 4.4V; I = 14µA

Q

1555l18f LT/TP 0601 2K • PRINTED IN USA

LINEAR TECHNOLOGY CORPORATION 2000

LinearTechnology Corporation

1630 McCarthy Blvd., Milpitas, CA 95035-7417

8

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(408)432-1900 FAX:(408)434-0507 www.linear-tech.com


型号：	LTC1555L-1.8
厂家：	Linear
描述：	SIM Power Supply and Level Translator SIM电源和电平转换器转换器电平转换器
文件：	总8页 (文件大小：146K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

LTC1555L-1.8 [Linear]

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