4.55V threshold — why it matters for 5V rail supervision
Its 4.55V threshold trips when the supply drops below that level, generating an active-low reset output — an open-drain signal that holds the downstream processor in reset until the rail recovers and the 120ms minimum timeout elapses.
Reset timeout and output type
The 120ms minimum reset timeout is long enough to cover most MCU and SoC power-up sequences without needing an external delay capacitor. The open-drain output lets you wire-OR the reset signal with other supervisors or a manual reset button — a common trick on multi-rail boards where one supervisor handles the core and another handles the I/O rail.
Housed in a SOT-23-5 (SC-74A) package, the part is surface-mount and fits a compact footprint — easy to route on two-layer PCBs.