Supervisor IC for 3V rails — open-drain, active-low reset
The Analog Devices MAX6315US30D3+ is a simple reset/power-on reset IC that monitors a single 3V supply rail and asserts an active-low, open-drain reset output when the voltage falls below the 3V threshold. The reset output remains asserted for a minimum of 140ms after the supply recovers, providing a clean startup sequence for microprocessors, DSPs, or FPGAs. The open-drain output allows wired-OR connection with other reset sources and requires an external pull-up resistor to the monitored rail or another logic voltage. This part is a straightforward, no-frills supervisor for a 3V system where the designer needs a guaranteed reset pulse and does not require manual reset input or watchdog timer functionality.
Temperature grade and environment
Rated for operation from -40°C to 125°C, this part handles the full industrial temperature span and reaches into automotive under-hood environments. The wide range means it can sit on a motor drive PCB near heat-generating power stages, in an outdoor telecom enclosure, or in an engine bay electronics module without derating concerns. The SOT-23-4 package keeps the board footprint small — useful when the supervisor is placed close to the supervised processor, not at a central power distribution point.
Lifecycle and supply position
Listed as Active on the manufacturer's lifecycle status.
140ms reset timeout — what it means for system boot
The 140ms minimum reset timeout allows power supplies to settle after brown-out or power-up before the processor starts executing code.