ExpressCard slot power — three rails, one switch
The TPS2231MRGPR is a dedicated ExpressCard™ power switch from Texas Instruments, integrating three high-side outputs to deliver the 1.5 V and 3.3 V rails an ExpressCard socket requires. Each output is rated for 1.3 A continuous, and the typical on-resistance of 45 mOhm keeps the voltage drop low enough that the card sees the full rail under load.
Fault protection — fixed limits, no trimming
The switch includes fixed current limiting and over-temperature shutdown. These are not adjustable — the trip thresholds are set internally, so the load profile must stay within the device's safe operating area without relying on external programming. The power-good and status-flag outputs give the system controller a clean handshake when the rails are within tolerance.
Package and thermal — the exposed pad matters
The surface-mount assembly must include a solder-paste stencil aperture covering at least 50% of the pad area to avoid voids, and the board layout should connect the pad to a ground plane for thermal relief.
Temperature grade — industrial, not automotive
It is not AEC-Q100 qualified, so it is not intended for under-hood or chassis-mounted automotive applications.