Three-rail supervisor for ATX and industrial PSUs
The Texas Instruments TPS3513DRG4 is a multi-voltage supervisor designed to monitor the three primary rails in an ATX or industrial power supply: 3.3 V, 5 V, and 12 V. It asserts an active-low, open-drain reset output when any monitored voltage falls below its threshold, and holds reset for a minimum of 200 ms after all rails recover. This part is common in PC power supplies, base-station power modules, and multi-rail industrial systems where a single supervisor must watch the main voltage domains.
Voltage thresholds and reset behaviour
The reset output is active low and open drain, so it can be wire-OR'd with other reset signals or pulled up to a logic rail of your choice. The 200 ms minimum reset timeout gives downstream loads—like an MCU or FPGA—enough time to stabilise before the system starts executing code.
The 14-SOIC footprint is a standard supervisor package; the 0.050-inch lead pitch is manageable on a two-layer board if the supply decoupling caps are placed close to the VDD pin.