PCMCIA power switch — four 1 A channels with integrated protection
It integrates four high-side outputs, each rated for 1 A continuous, with a typical on-resistance of 95 mOhm per channel — low enough to keep the voltage drop under 100 mV at full load, which matters when the card-side supply margin is tight. The switch is controlled via a serial interface and reports card-present status through a dedicated flag output, matching the PCMCIA power-control protocol used in notebook and embedded card-reader designs.
Protection scheme — no external sense resistor needed
Fault protection includes fixed current limiting and over-temperature shutdown, both built into the die. The current limit is preset — no external sense resistor or trim network — and the thermal foldback prevents the switch from exceeding its safe junction temperature during a sustained overload or short circuit. The input-to-output ratio is 3:4, meaning three control signals manage four output channels, which reduces the GPIO count required from the host controller.
The SSOP footprint is a common choice for PCMCIA power controllers in multi-layer PCBs where the card slot sits near the board edge.