Document
LTC4557 Dual SIM/Smart Card Power Supply and Interface
FEATURES
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DESCRIPTIO
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U APPLICATIO S
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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
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. 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.
, LTC and LT are registered trademarks of Linear Technology Corporation. *U.S. Patent No. 6,356,140
GSM and 3G Cellular Phones Wireless P.O.S. Terminals Multiple SAM Card Interface
TYPICAL APPLICATIO
DVCC
VBATT DVCC 1.2V TO 4.4V 3V TO 6V 0.1µF DVCC CLKIN RSTIN DATA µCONTROLLER VBATT I/OA RSTA CLKA VCCA LTC4557 GND 1µF VCCB ENABLE M0 M1 CLKB RSTB I/OB C1 C3 C2 C7 VCC CLK 1.8V/3V SMART RST CARD I/O GND C5
4557 TA01
0.1µF C7 C2 C3 C1 1µF I/O RST 1.8V/3V SIM CLK CARD VCC GND C5
RSTX 5V/DIV CLKX 5V/DIV I/OX 5V/DIV VCCX 2V/DIV CVCCX = 1µF 10µs/DIV
4557 G07
U
Deactivation Sequence
4557f
U
1
LTC4557
ABSOLUTE
(Note 1)
AXI U
RATI GS
U U W PACKAGE/ORDER I FOR ATIO
TOP VIEW
CLKA
RSTA
I/OA
DATA
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°
ENABLE
RSTB
CLKB
I/OB
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER VBATT Operating Voltage IVBATT Operating Current DVCC Operating Voltage IDVCC Operating Current IDVCC Shutdown Current IVBATT Shutdown Current Input Power Supply
The q 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.
CONDITIONS
q
SIM Card Sup.