ExpressCard slot power switch — three outputs, two rails
The Texas Instruments TPS2231RGPTG4 is a three-output high-side power switch designed for ExpressCard™ slots. It switches the 1.5 V and 3.3 V rails that an ExpressCard module expects, with each of the three outputs rated for 1.3 A continuous.
Typical on-resistance is 45 mOhm. The fixed current-limiting and over-temperature protection handle fault conditions without an external sense resistor.
Power Good and Status Flag — host-side visibility
Power Good and Status Flag outputs let the host controller know the output rail is within regulation or that a fault (over-current, over-temperature) has occurred. No polling of the output voltage is needed — the flags are open-drain and can be wired directly to a GPIO.
Package and supply — QFN-20, no Vcc required
Housed in a 20-VFQFN exposed-pad package (4x4 mm body), the TPS2231RGPTG4 is surface-mount and requires no Vcc supply pin — the switch is self-powered from the load rails.