LTC4557 Datasheet | Linear Technology

LTC4557 Dual SIM/Smart Card Power Supply and Interface Features s s s s s s s DESCRIPTIO s s s s U APPLICATIO S s s s 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 patible Dynamic Pull-Ups Deliver Fast Signal Rise Times- Built-In Fault Protection Circuitry Automatic Activation/Deactivation Sequencing Circuitry Low Operating/Shutdown Current >10k V ESD on SIM Card Pins patible 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 50m A 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 Deactivation Sequence 4557f ABSOLUTE (Note 1) AXI...