The APL3546A is a power-distribution switch with some protection functions. The device incorporates a 78mW Nchannel MOSFET power switch that is controlled by an enable logic pin and has a SS pin dedicated to soft start ramp-up rate control that can be used in application where the inrush current is concerned.

　　The device integrates some protection features， including current limit protection， over-temperature protection， UVLO and current limit setting. The current limit protection can protect down-stream devices from catastrophic failure by limiting the output current at current limit threshold during over-load or short circuit events. The over-temperature protection function shuts down IC when the junction temperature rises beyond 150 oC. The UVLO function keeps the power switch in off state until there is a valid input voltage present. The current limit can be set by connecting resistor from the current limit adjustable pin ISET to ground.