5V rail watchdog — what the 140ms timeout buys you
The Texas Instruments TPS3703A5500DSER is a simple reset/power-on reset supervisor that monitors a single 5V supply rail. When the voltage drops below the 5V threshold, it pulls the reset output low and holds it there for a minimum of 140ms after the rail recovers. That 140ms window gives the system power supply and oscillator time to stabilise before the microcontroller or SoC tries to boot — without it you can get spurious start-up sequences or partial resets that look like firmware hangs. The active-low, open-drain output lets you wire-OR multiple supervisors onto one reset line or drive a GPIO directly.
Industrial temp range and tiny package — field-fit realities
The 6-WSON package (1.5x1.5 mm) is small enough to tuck next to the MCU on a dense board, but that exposed pad needs a thermal via stitch to the ground plane — without it the part can hit thermal shutdown if the ambient is near the 125°C limit and the output is sourcing a few mA. No lab bench needed for the swap, but the reflow profile matters: MSL level is not in the record, so treat it as MSL 1 unless the reel label says otherwise.
ROHS3 compliant per the record, so it passes the usual European and California regulatory gates without an exemption hunt.