LTC4555 Datasheet | Linear Technology

SIM Power Supply and Level Translator Features n SIM Power Supply: 1.8V/3V at 50m A n Input Voltage Range: 3V to 6V n Controller Voltage Range: 1.2V to 4.4V n 14k V ESD On All SIM Contact Pins n Meets All ETSI, IMT-2000 and ISO7816 SIM/Smart Card Interface Requirements n Level Translators to 1.8V or 3V n 20µA Operating Current n Logic-Controlled Shutdown (ISD < 1µA) n Available in a Low Profile, 16-Pin (3mm × 3mm) QFN Package Applications n SIM Interface in 3G Cellular Telephones n Smart Card Readers Description The LTC®4555 provides power conversion and signal level shifting needed for low voltage 2.5G and 3G cellular telephones to interface with 1.8V or 3V subscriber identity modules (SIMs). The part meets all type approval requirements for 1.8V and 3V SIMs and smart cards. The part contains an LDO linear regulator to supply SIM power at either 1.8V or 3V from a 3V to 6V input. The output voltage is selected with a single pin 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 20µA operating current and <1µA shutdown current. Board area is minimized by the 3mm × 3mm leadless QFN package. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Thin SOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical Application VCC CONTROLLER Typical SIM Interface VBAT (1.2V TO 4.4V) (3V TO 6V) 0.1µF DVCC SHDN VBAT VCC VSEL DATA I/0 0.1µF SIM/ SMART CARD INTERFACE VCC 1µF RST CLK I/0 4555 TA01 For more information .linear./LTC4555 4555fc...