AEC-Q100 grade-1 supervisor for 5V rails
It monitors a single voltage rail with a 4.6V threshold, asserting an Active-Low, Open-Drain reset output when the supply drops below that level. The output stays low for a typical reset timeout of 619ms after the rail recovers, giving the downstream MCU or SoC time to stabilise before release.
Threshold and timeout — what they mean for system design
A 4.6V threshold is a tight window on a nominal 5V rail — it triggers reset at roughly 8% below nominal, which catches brown-out events before the logic supply drops out of the MCU's valid operating range. The 619ms timeout (typical) gives bulk capacitance on the rail time to recharge before the system re-enables. The Open-Drain output allows the reset signal to be wire-ORed with other supervisors or pulled up to a different voltage (e.g. 3.3V) to match the downstream logic level. The Active-Low polarity is the most common convention for microcontroller reset inputs.
It is supplied in a SOT-23-5 package (SC-74A, SOT-753) — a 5-lead surface-mount footprint that fits into compact ECU layouts without requiring a dedicated power-management IC area.