The LTC1955EUH#PBF is a dual Smart Card Interface with serial control. It provides all necessary supervisory and power control functions for two smart cards, two S.A.M. cards or a combination of S.A.M. and smart cards. It provides a charge pump for battery-powered applications as well as all necessary level shifting circuitry. The card voltages can be independently set to 1.8, 3 or 5V. Both card interfaces include a card detection channel with automatic debounce circuitry. To reduce wiring costs, the LTC1955 interfaces to a microcontroller via a simple 4-wire serial interface. Multiple devices may be connected in daisy chain fashion so that the number of wires to the card socket board is independent of the number of sockets. Status data is returned over the same interface. Extensive security features ensure proper deactivation sequencing in the event of a supply fault or a smart card electrical fault.
Power management and control for two smart cards
Control/status serial port may be daisy-chained for multicard applications