LINER LTC4557

LTC4557
Dual SIM/Smart Card
Power Supply and Interface
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FEATURES
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DESCRIPTIO
The LTC®4557 provides power conversion and signal level
translation needed for 2.5G and 3G cellular telephones to
interface with 1.8V or 3V subscriber identity modules
(SIMs). The part meets all requirements for 1.8V and 3V
SIMs. The part contains LDO regulators to power 1.8V or
3V SIM cards from a 2.7V to 5.5V input. The output
voltages can be set using the two voltage selection pins
and up to 50mA of load current can be supplied.
Power Management and Signal Level Translators
for Two SIM Cards or Smart Cards
Independent 1.8V/3V VCC Control for Both Cards
Automatic Level Translation
ISO7816, ETSI and EMV Compatible
Dynamic Pull-Ups Deliver Fast Signal Rise Times*
Built-In Fault Protection Circuitry
Automatic Activation/Deactivation Sequencing
Circuitry
Low Operating/Shutdown Current
>10kV ESD on SIM Card Pins
Compatible with EMV Fault Tolerance Requirements
Available in 16-Lead (3mm × 3mm) QFN Package
Internal level translators allow controllers operating with
supplies as low as 1.2V to interface with 1.8V or 3V smart
cards. Battery life is maximized by a low operating current
of less than 100µA and a shutdown current of less than
1µA. Board area is minimized by the low profile 3mm ×
3mm × 0.75mm leadless QFN package.
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APPLICATIO S
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GSM and 3G Cellular Phones
Wireless P.O.S. Terminals
Multiple SAM Card Interface
, LTC and LT are registered trademarks of Linear Technology Corporation.
*U.S. Patent No. 6,356,140
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TYPICAL APPLICATIO
VBATT
DVCC
1.2V TO 4.4V 3V TO 6V
DVCC
Deactivation Sequence
0.1µF
0.1µF
DVCC
CLKIN
VBATT
I/OA
RSTIN
RSTA
DATA
C7
C2
C3
CLKA
C1
VCCA
µCONTROLLER
LTC4557
1µF
I/O
RST 1.8V/3V
SIM
CLK
CARD
VCC
GND
C5
GND
1µF
VCCB
ENABLE
CLKB
M0
RSTB
M1
I/OB
C1
C3
C2
C7
VCC
CLK 1.8V/3V
SMART
RST
CARD
I/O
GND
RSTX
5V/DIV
CLKX
5V/DIV
I/OX
5V/DIV
VCCX
2V/DIV
CVCCX = 1µF
10µs/DIV
4557 G07
C5
4557 TA01
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LTC4557
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AXI U
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ABSOLUTE
RATI GS
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PACKAGE/ORDER I FOR ATIO
(Note 1)
ORDER PART
NUMBER
ENABLE
I/OB
RSTB
CLKB
TOP VIEW
LTC4557EUD
16 15 14 13
VCCB 1
12 M0
DVCC 2
11 M1
17
VBATT 3
10 CLKIN
VCCA 4
6
7
8
CLKA
I/OA
DATA
9
5
RSTA
VBATT, DVCC, DATA, RSTIN, CLKIN,
ENABLE, M0, M1 to GND ............................ – 0.3V to 6V
I/OA, CLKA, RSTA ........................ – 0.3V to VCCA + 0.3V
I/OB, CLKB, RSTB ........................ – 0.3V to VCCB + 0.3V
ICCA,B (Note 4) ...................................................... 80mA
VCCA,B Short-Circuit Duration ......................... Indefinite
Operating Temperature Range (Note 3) .. – 40°C to 85°C
Storage Temperature Range ................... – 65°C to 125°
RSTIN
UD PART MARKING
LAHP
UD PACKAGE
16-LEAD (3mm × 3mm) PLASTIC QFN
TJMAX = 125°C, θJA = 68°C/W, θJC = 42°C/W
EXPOSED PAD (PIN 17) IS GND
(MUST BE SOLDERED TO PCB)
Consult LTC Marketing 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 TA = 25°C. VBATT = 3.3V, DVCC = 1.8V, unless otherwise specified.
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
5.5
V
100
100
µA
µA
Input Power Supply
VBATT Operating Voltage
IVBATT Operating Current
●
VCCA = 3V, VCCB = 0V, ICCA = ICCB = 0µA
VCCA = 1.8V, VCCB = 0V, ICCA = ICCB = 0µA
2.7
65
65
●
●
DVCC Operating Voltage
●
5.5
V
IDVCC Operating Current
●
6
10
µA
IDVCC Shutdown Current
●
0.1
1
µA
DVCC = 0V
●
●
0.4
0.1
2.5
1.0
µA
µA
VCCA,B Output Voltage
3V Mode, 0mA < ICCA,B < 50mA
1.8V Mode, 0mA < ICCA,B < 3OmA
●
●
3.0
1.8
3.25
1.95
V
V
Channel Turn-On Time
ICCA,B = 0mA,
●
1.3
2.5
ms
VOL
Low Level Output Voltage
Sink Current = –200µA (Note 2)
●
0.2
V
VOH
High Level Output Voltage
Source Current = 200µA (Note 2)
● VCCA,B –
IVBATT Shutdown Current
1.2
SIM Card Supplies
ENABLE to
IOA/B
2.75
1.65
CLKA, CLKB
V
0.2
Rise, Fall Time
Loaded with 33pF (10% to 90%) (Note 2)
●
16
CLKA, CLKB Frequency
(Note 2)
●
VOL
Low Level Output Voltage
Sink Current = –200µA (Note 2)
●
VOH
High Level Output Voltage
Source Current = 200µA (Note 2)
● VCCA,B –
10
ns
MHz
RSTA, RSTB
0.2
V
V
0.2
Rise, Fall Time
Loaded with 33pF (10% to 90%) (Note 2)
●
100
ns
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LTC4557
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VBATT = 3.3V, DVCC = 1.8V, unless otherwise specified.
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
VOL
Low Level Output Voltage
Sink Current = –1mA (VDATA = 0V) (Note 2)
●
VOH
High Level Output Voltage
Source Current = 20µA (VDATA = VDVCC)
(Note 2)
●
Rise Time
Loaded with 33pF (10% to 90%) (Note 2)
●
200
500
ns
Short-Circuit Current
VDATA = 0V (Note 2)
●
5
10
mA
VOL
Low Level Output Voltage
Sink Current = –500µA (VI/OA,B = 0V)
●
0.3
V
VOH
High Level Output Voltage
Source Current = 20µA (VI/OA,B = VCCA,B)
●
Rise Time
Loaded with 33pF (10% to 90%)
●
I/OA, I/OB
0.3
0.85 •
VCCA,B
V
V
DATA
0.8 •
DVCC
V
200
500
ns
0.15 •
DVCC
V
RSTIN, CLKIN, ENABLE, M0, M1
VIL
Low Input Threshold
●
VIH
High Input Threshold
●
0.85 •
DVCC
Input Current (IIH, IIL)
●
–1
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: This specification applies to both 1.8V and 3V smart cards.
V
1
µA
Note 3: The LTC4557E is guaranteed to meet performance specifications
from 0°C to 70°C. Specifications over the – 40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 4: Based on long term current density limitations.
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LTC4557
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TYPICAL PERFOR A CE CHARACTERISTICS
I/O X Short-Circuit Current
vs Temperature
No Load Supply Current vs VBATT
6.0
SHORT-CIRCUIT CURRENT (mA)
TA = 25°C
ICCA = ICCB = 0µA
SUPPLY CURRENT (µA)
75
DROPOUT
70
VCCX = 3V
65
VCCX = 1.8V
60
55
2.7
3.1
3.5 3.9 4.3
4.7
SUPPLY VOLTAGE (V)
5.1
140
VDVCC = VBATT = 5.5V
VCCX = 3V
5.5
5.0
4.5
35
10
TEMPERATURE (°C)
60
85
60
40
10
100
1000
10000
LOAD CURRENT (µA)
DVCC Shutdown Current
vs Supply Voltage
0.7
VDVCC = 1.8V
VBATT = 5.5V
TA = –40°C TO 85°C
0.6
SUPPLY CURRENT (µA)
2.5
TA = –40°C
2.0
100000
4557 G03
4557 G02
VBATT Shutdown Current
vs Supply Voltage
SUPPLY CURRENT (µA)
80
0
–15
4557 G01
3.0
100
20
4.0
–40
5.5
TA = 25°C
VBATT = 3.1V
120
SUPPLY CURRENT (µA)
80
VBATT Quiescent Current
(IVBATT – ICC) vs Load Current
TA = 25°C
1.5
1.0
TA = 85°C
0.5
0.5
0.4
0.3
0.2
0.1
0
2.7
3.1
4.7
3.5 3.9 4.3
SUPPLY VOLTAGE (V)
5.1
5.5
0
1.2 1.6 2 2.4 2.8 3.2 3.6 4 4.4 4.8 5.2 5.6
SUPPLY VOLTAGE (V)
4557 G04
4557 G05
Deactivation Sequence,
CVCCX = 1µF
Data – I/O Channel, CL = 40pF
I/0X
1V/DIV
RSTX
5V/DIV
CLKX
5V/DIV
DATA
1V/DIV
I/OX
5V/DIV
VCCX
2V/DIV
CL = 40pF
200ns/DIV
4557 G06
CVCCX = 1µF
10µs/DIV
4557 G07
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LTC4557
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PI FU CTIO S
DVCC (Pin 2): Power. Reference voltage for the control
logic.
VBATT (Pin 3): Power. Supply voltage for the analog
sections of the LTC4557.
VCCA/VCCB (Pins 4, 1): Card Socket. The VCCA/VCCB pins
should be connected to the VCC pins of the respective card
sockets. The activation of the VCCA/VCCB pins is controlled
by the M0, M1 and ENABLE inputs. They can be set to 0V,
1.8V or 3V. Only one of the two, either VCCA or VCCB, may
be active at a time.
CLKA/CLKB (Pins 5, 16): Card Socket. The CLKA/CLKB
pins should be connected to the CLK pins of the respective
card sockets. The CLKA/CLKB signals are derived from the
CLKIN pin. They provide a level shifted CLKIN signal to the
selected card. The CLKA/CLKB pins are gated off until
VCCA/VCCB attain their correct values.
RSTA/RSTB (Pins 6, 15): Card Socket. The RSTA/RSTB
pins should be connected to the RST pins of the respective
card sockets. The RSTA/RSTB signals are derived from
the RSTIN pin. When a card is selected, its RST pin follows
RSTIN. The RSTA/RSTB pins are gated off until VCCA/VCCB
attain their correct values.
I/OA, I/OB (Pins 7, 14): Card Socket. The I/OA, I/OB pins
connect to the I/O pins of the respective card sockets.
When a card is selected, its I/O pin transmits/receives data
to/from the DATA pin. The I/OA, I/OB pins are gated off
until VCCA/VCCB attain their correct values.
DATA (Pin 8): Input/Output. Microcontroller side data I/O
pin. The DATA pin provides the bidirectional communication path to both cards. Only one of the cards may be
selected to communicate via the DATA pin. The pin possesses a dynamically activated pull-up current source,
allowing the controller to use an open-drain output. The
current source maintains a HIGH state. This pin is held
HIGH by a weak pull-up when the ENABLE pin is LOW.
RSTIN (Pin 9): Input. The RSTIN pin supplies the reset
signal to the cards. It is level shifted and transmitted
directly to the RST pin of the selected card.
CLKIN (Pin 10): Input. The CLKIN pin supplies the clock
signal to the cards. It is level shifted and transmitted
directly to the CLK pin of the selected card.
M0/M1 (Pins 12, 11): Inputs. The M0 and M1 pins select
which set of SIM/smart card pins are active and at which
voltage level they operate. The truth table for these pins
follows:
M1
M0
0
0
SELECTED CARD/VOLTAGE
Card A/1.8V
0
1
Card A/3V
1
0
Card B/1.8V
1
1
Card B/3V
ENABLE (Pin 13): Input. The ENABLE pin shuts down the
chip when LOW.
EXPOSED PAD (Pin 17): Chip Ground. This ground pad
must be soldered directly to a PCB ground plane.
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LTC4557
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BLOCK DIAGRA
VCCA 4
DVCC
VBATT
2
3
LDOA
1 VCCB
LDOB
DVCC
I/OA 7
14 I/OB
RSTA 6
15 RSTB
CLKA 5
16 CLKB
DVCC
DATA 8
RSTIN 9
CONTROL
LOGIC
CLKIN 10
17
GND
12
11
ENABLE M0
13
M1
4557 BD
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LTC4557
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OPERATIO
The LTC4557 features two independent smart card channels. Only one of these channels may operate at a time.
Each channel is able to output two voltage levels: 1.8V
and 3V. The channel selection and voltage selection are
controlled by the ENABLE, M0 and M1 pins as shown in
Table 1.
Table 1. Channel and Voltage Truth Table
ENABLE
M1
M0
SELECTED CARD/VOLTAGE
1
0
0
Card A/1.8V
1
0
1
Card A/3V
1
1
0
Card B/1.8V
1
1
1
Card B/3V
0
X
X
A and B Disabled
Bidirectional Channels
The bidirectional channels are level shifted to the appropriate VCCA,B voltages at the I/OA,B pins. An NMOS pass
transistor performs the level shifting. The gate of the
NMOS transistor is biased such that the transistor is
completely off when both sides have relinquished the
channel. If one side of the channel asserts a LOW, then the
transistor will convey the LOW to the other side. Note that
current passes from the receiving side of the channel to
the transmitting side. The low output voltage of the receiving side will be dependent upon the voltage at the transmitting side plus the IR drop of the pass transistor.
When a card socket is selected, it becomes a candidate to
drive data on the DATA pin and likewise receive data from
the DATA pin. When a card socket is deselected, the
voltage on its I/OA,B pin will be disabled and set to LOW.
If both cards are deselected, a weak pull-up ensures that
the DATA pin is held HIGH.
Dynamic Pull-up Current Sources
The current sources on the bidirectional pins (DATA/
I/OA,B) are dynamically activated to achieve a fast rise
time with a relatively small static current. Once a bidirectional pin is relinquished, a small start-up current begins
to charge the node. An edge rate detector determines if the
pin is released by comparing its slew rate with an internal
reference value. If a valid transition is detected, a large
pull-up current enhances the edge rate on the node. The
higher slew rate corroborates the decision to charge the
node thereby affecting a dynamic form of hysteresis.
Reset Channels
When a card is selected, the reset channel provides a level
shifted path from the RSTIN pin to the RSTA,B pin. When
a card is deselected its reset pin is pulled LOW.
LOCAL
SUPPLY
+
VREF
ISTART
–
dv
dt
4557 F01
BIDIRECTIONAL
PIN
Figure 1. Dynamic Pull-Up Current Source
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LTC4557
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OPERATIO
Activation/Deactivation
Activation and deactivation sequencing is handled by
built-in circuitry. The activation sequence is initiated by
bringing the ENABLE pin HIGH. The activation sequence is
outlined below:
3. The I/O channel is disabled and the I/O pin is brought
LOW approximately 9µs after the ENABLE is brought
LOW.
4. VCC will be depowered after the I/O pin is brought LOW.
1. The RST, CLK and I/O pins are held LOW.
The activation or deactivation sequences will take place
every time a card socket is enabled or disabled.
2. VCC is enabled.
Fault Protection
3. After VCC is stable at its selected level, The I/O and RST
channels are enabled.
The VCC, I/O, RST and CLK pins are all protected against
short-circuit faults. While there are no logic outputs to
indicate that a fault has occurred, these pins will be able
to tolerate the fault condition until it has been removed.
4. The clock channel is enabled on the rising edge of the
second clock cycle after the I/O pin is enabled.
The deactivation sequence is initiated by bringing the
ENABLE pin LOW. The deactivation sequence is outlined
below:
1. The reset channel is disabled and RST is brought LOW.
The VCCA,B, I/OA,B, and RSTA,B pins possess fault protection circuitry which will limit the current available to the
pins. Each VCC pin is capable of supplying approximately
90mA (typ) before the output voltage is reduced.
2. The clock channel is disabled and the CLK pin is brought
LOW two clock cycles after ENABLE is brought LOW. If
the clock is not running, the clock channel will be
disabled approximately 9µs after the ENABLE pin is
brought LOW.
The CLKA,B pins are designed to tolerate faults by reducing the current drive capability of their output stages. After
a fault is detected by the internal fault detection logic, the
logic waits for a fault detection delay to elapse before
reducing the current drive capability of the output stage.
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LTC4557
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APPLICATIO S I FOR ATIO
10kV ESD Protection
capacitors can be compared directly by case size rather
than specified value for a desired minimum capacitance.
All smart card pins (CLKA,B, RSTA,B, I/OA,B, VCCA,B and
GND) can withstand over 10kV of human body model ESD
in-situ. In order to ensure proper ESD protection, careful
board layout is required. The GND pad should be tied
directly to a ground plane. The VCCA,B capacitors should be
located very close to the VCCA,B pins and tied immediately
to the ground plane.
The VCCA,B outputs should be bypassed to GND with a 1µF
capacitor. VBATT should be bypassed with a 0.1µF ceramic
capacitor. Capacitors should be placed as close to the
LTC4557 as possible for improved ESD tolerance.
The following capacitors are recommended for use with
the LTC4557:
Capacitor Selection
A total of four capacitors are required for proper bypassing
of the LTC4557. An input bypass capacitor is required at
VBATT and DVCC. Output bypass capacitors are required on
each of the smart card VCCA,B pins. Due to their extremely
low equivalent series resistance (ESR), only multilayer
ceramic chip capacitors should be used to ensure proper
stability and ESD protection.
TYPE
VALUE
CVCC,
VCCA/B
X5R
1µF
CASE SIZE MURATA PART NUMBER
0603
GRM188R60J105KA01
CDVCC,
DVCC
X5R
0.1µF
0402
GRM155R61A104KA01
Compliance Testing
Inductance due to long leads on type approval equipment
can cause ringing and overshoot that leads to testing
problems. Small amounts of capacitance and damping
resistors can be included in the application without compromising the normal electrical performance of the
LTC4557 or smart card system. Generally a 100Ω resistor
and a 20pF capacitor will accomplish this as shown in
Figure 2.
There are several types of ceramic capacitors available
each having considerably different characteristics. For
example, X7R/X5R ceramic capacitors have excellent voltage and temperature stability but relatively low packing
density. Y5V ceramic capacitors have apparently higher
packing density but poor performance over their rated
voltage or temperature ranges. Under certain voltage and
temperature conditions Y5V and X7R/X5R ceramic
1µF
C1
VCCX
CLKX
LTC4557
RSTX
0.1µF
100Ω
100Ω
20pF
C3 SMART
CARD
C2 SOCKET
100Ω 20pF
I/OX
20pF
C7 C5
4557 F02
Figure 2. Additional Components for Improved Compliance Testing
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LTC4557
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APPLICATIO S I FOR ATIO
Shutdown Modes
Ultralow Shutdown Current
The LTC4557 can enter a low current shutdown mode by
one of two methods. First, the ENABLE pin can be brought
LOW by the controller to directly shut down the part. The
other way is to lower DVCC below 1.2V, at which point the
power-on-reset circuit automatically puts the part into
shutdown mode.
In either of the two shutdown modes, the shutdown
current is less than 1µA. For applications that require
virtually zero shutdown current, the DVCC pin can be
grounded. This will reduce the VBATT current to well under
a single microampere.
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LTC4557
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PACKAGE DESCRIPTIO
UD Package
16-Lead Plastic QFN (3mm × 3mm)
(Reference LTC DWG # 05-08-1691)
0.70 ±0.05
3.50 ± 0.05
1.45 ± 0.05
2.10 ± 0.05 (4 SIDES)
PACKAGE OUTLINE
0.25 ±0.05
0.50 BSC
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
3.00 ± 0.10
(4 SIDES)
BOTTOM VIEW—EXPOSED PAD
0.23 TYP
R = 0.115
(4 SIDES)
TYP
15 16
0.75 ± 0.05
PIN 1
TOP MARK
(NOTE 6)
0.40 ± 0.10
1
1.45 ± 0.10
(4-SIDES)
2
(UD) QFN 0603
0.200 REF
0.00 – 0.05
NOTE:
1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE MO-220 VARIATION (WEED-2)
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION
ON THE TOP AND BOTTOM OF PACKAGE
0.25 ± 0.05
0.50 BSC
4557f
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
11
LTC4557
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TYPICAL APPLICATIO
VBATT
DVCC
1.2V TO 4.4V 3V TO 6V
DVCC
C3
2
0.1µF
DVCC
10
CLKIN
9
RSTIN
8
DATA
µCONTROLLER
LTC4557
GND
13
12
11
VCCB
ENABLE
CLKB
M0
RSTB
M1
C4
0.1µF
3
VBATT
5
CLKA
6
RSTA
7
I/OA
4
VCCA
I/OB
C7
C2
C3
C1
17
C1
1µF
1
C2
1µF
CLK
RST 1.8V/3V
SIM
I/O
CARD
VCC
GND
C5
C1
16
C3
15
C2
14
C7
VCC
CLK 1.8V/3V
SMART
RST
CARD
I/O
GND
C5
4557 TA02
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LTC3250-1.5
250mA, 1.5MHz, High Efficiency Step-Down Charge Pump
85% Efficiency, VIN: 3.1V to 5.5V, VOUT = 1.2V/1.5V, IQ = 35µA,
ISD < 1µA, ThinSOT
LTC3251
500mA, 1MHz to 16MHz, Spread Spectrum Step-Down
Charge Pump
85% Efficiency, VIN: 3.1V to 5.5V, VOUT: 0.9V to 1.6V, 1.2V/1.5V,
IQ = 9µA, ISD < 1µA, MS10
LTC4555
SIM Power Supply and Level Translator for 1.8V/3V SIM Cards
VIN: 3V to 6V, VOUT = 1.8V/3V, IQ = 40µA, ISD < 1µA, QFN16
LTC4556
Smart Card Interface with Serial Control for 1.8V/3V/5V
VIN: 2.7V to 5.5V, VOUT = 1.8V/3V/5V, IQ = 250µA, ISD < 1µA,
QFN24
4557f
12
Linear Technology Corporation
LT/TP 0204 1K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
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www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2004