MAX691EWE

The MAX691EWE from Maxim Integrated is part of a family of supervisory circuits that reduce component count for power supply monitoring and battery control in microprocessor systems. This device integrates essential functions such as µP reset, backup-battery switchover, watchdog timer, and power-failure warning.

Key features include a precision voltage monitor at 4.65V, adjustable reset and watchdog timeout periods, and battery backup power switching. It also provides a 1.3V threshold detector for power fail or low battery warnings. With a low standby current of 1µA in battery backup mode, it helps extend battery life.

The MAX691EWE is supplied in a 16-pin package and is suitable for surface mount applications. Its integrated functions help improve system reliability and accuracy compared to discrete component solutions. Applications include computers, controllers, intelligent instruments, and automotive systems requiring critical µP power monitoring.

This supervisory circuit is designed to protect microprocessor-based systems during power-up, power-down, and brownout conditions. It also offers onboard gating of chip enable signals to protect against erroneous data writes to RAM during low VCC events.