The NCN4557 is a dual interface analog circuit designed to translate the voltages between SIM Cards, SAM Cards or Smart Cards and a microcontroller (or similar control device). It integrates two LDOs for power conversion and three level shifters per channel allowing the management of two independent chip cards. The device fulfills the ISO-7816 and EMV smart card interface requirements as well as the GSM and 3G mobile standard. Due to a built-in sequencer, the device enables automatic activation and deactivation. Through the ENABLE pin a low current shutdown mode can be activated extending the battery life. The card power supply voltage (1.8 V or 3.0 V) and the card socket A or B are selected using two dedicated pins (SEL0 & SEL1).