Four-rail watchdog in a six-pin package
The MAX6710PUT+: This lets a single SOT-23-6 part cover the core, I/O, and auxiliary voltages on a mixed-logic board without cascading multiple supervisor ICs. When any monitored voltage drops below its threshold, the active-low open-drain reset output asserts and holds for a minimum of 140 ms after all rails recover — long enough for the downstream MCU or FPGA to complete its power-on-reset sequence.
The 140 ms minimum reset timeout is the key number for a board-level debug: if a rail glitches shorter than that, the supervisor holds the system in reset until the supply is stable. On a board with a known brown-out symptom, measuring the reset pin with a scope tells you which rail actually died — the scorch mark on the regulator may be the symptom, not the cause. Operating from -40°C to 85°C, this part covers the industrial temperature band — suitable for outdoor telecom cabinets, factory-floor controllers, and engine-bay electronics where the ambient can swing past the commercial 70°C ceiling.