The NCN4557 is a dual interface analog circuit designed to translate the voltages between SIM, SAM 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 ISO7816 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.

Features
• Supports 1.8 V or 3.0 V Operating SIM/SAM/Smart Cards
• The LDOs are able to Supply more than 50 mA Under 1.8 V and 3.0 V
• Built−in Active and Passive Pullup Resistor for I/O and
   CRD_IOA/B Pins in Both Directions
• All Pins are Fully ESD Protected According to ISO−7816
   Specifications – ESD Protection on Card Pins in Excess of 8.0 kV
   (JEDEC HBM)
• Built−in Sequencer for Activation and Deactivation
• Supports up to more than 5.0 MHz Clock
• Very Compact Low−Profile 3x3 QFN−16 Package
• These are Pb−Free Devices*

Applications
• SIM Card Interface Circuit for 2G, 2.5G and 3G Mobile Phones
• Wireless PC/Laptop Cards (PCMCIA Cards)
• POS Terminals (SAM Card Interfaces)
• Smart Card Readers