LTC1555L Series

SIM Power Supply and Level Translator

Catalog

SIM Power Supply and Level Translator

Part	Mounting Type	Operating Temperature [Max]	Operating Temperature [Min]	Channels per Circuit	Package / Case	Package / Case	Package / Case	Voltage - VCCB [Max]	Voltage - VCCB [Min]	Supplier Device Package	Features	Output Type	Translator Type	Channel Type	Number of Circuits	Voltage - VCCA [Max]	Voltage - VCCA [Min]
Analog Devices LTC1555CGN#PBF	Surface Mount	70 °C	0 °C	1	0.154 in	16-SSOP	3.9 mm	10 V	2.7 V	16-SSOP	SIM Card Interface Thermal-Shutdown Protection	Open Drain	Voltage Level	Bidirectional	1	5.5 V	1.8 V
Analog Devices LTC1555LEGN#PBF	Surface Mount	85 °C	-40 °C	1	0.154 in	16-SSOP	3.9 mm	6 V	2.6 V	16-SSOP	SIM Card Interface Thermal-Shutdown Protection	Open Drain	Voltage Level	Bidirectional	1	4.4 V	1.425 V
Analog Devices LTC1555LEGN#TRPBF	Surface Mount	85 °C	-40 °C	1	0.154 in	16-SSOP	3.9 mm	6 V	2.6 V	16-SSOP	SIM Card Interface Thermal-Shutdown Protection	Open Drain	Voltage Level	Bidirectional	1	4.4 V	1.425 V

Catalog

SIM Power Supply and Level Translator

Key Features

• Buck/Boost Charge Pump Generates 3V or 5V

• Input Voltage Range: 2.6V to 6V

• Controller VCCRange: 1.425V to 4.4V

• >10kV ESD on All SIM Contact Pins

• Short-Circuit and Overtemperature Protected

• 3V to 5V Signal Level Translators

• Very Low Operating Current: 40µA

• Very Low Shutdown Current: <1µA

• Soft-Start Limits Inrush Current at Turn-On

• 1MHz Switching Frequency

• Available in 16-Pin Narrow SSOP Package

Description

The LTC1555L provides power conversion and level shifting needed for low voltage GSM cellular telephones to interface with either 3V or 5V Subscriber Identity Modules (SIMs). The part contains a patented buck/boost charge pump DC/DC converter* that delivers a regulated VCCsupply 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 3V, 5V or direct connection to the VINpin.Internal level translators allow controllers operating with supplies as low as 1.425V to interface with 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 40µA 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.ApplicationsSIM Interface in GSM Cellular TelephonesSmart Card Readers