Texas Instruments' TXS4555 is a complete Smart Identity Module (SIM) card solution for interfacing wireless baseband processors with a SIM card to store I/O for mobile handset applications. The device complies with ISO/IEC Smart-Card Interface requirements as well as GSM and 3G mobile standards. It includes a high-speed level translator capable of supporting Class-B (2.95 V) and Class-C (1.8 V) interfaces, a low-dropout (LDO) voltage regulator that has output voltages that are selectable between 2.95 V Class-B and 1.8 V Class-C interfaces. The device has two supply voltage pins. VCC can be operated over the full range of 1.65 V to 3.3 V and V_BATT from 2.3 V to 5.5 V. VPWR is set to either 1.8 V or 2.95 V and is supplied by an internal LDO.