Maxim Integrated MAX691AEWE Microprocessor Supervisory Circuit

The Maxim Integrated MAX691AEWE is a highly integrated microprocessor (µP) supervisory circuit designed to monitor power supplies and µP activity in digital systems. It provides excellent circuit reliability and low cost by eliminating external components and adjustments when used with 5V-powered circuits.

This supervisory circuit features a combination of functions aimed at providing a robust solution for managing system integrity. Among its key features are a reset output during power-up, power-down, and brownout conditions. The reset signal ensures that the µP starts in a known state. Additionally, the MAX691AEWE includes a backup battery switchover function that maintains uninterrupted supply for RAM retention during main power failure.

The MAX691AEWE also incorporates a watchdog timer that can be set by an external capacitor to safeguard against system malfunctions. If the µP fails to provide a periodic signal to the timer, the MAX691AEWE will issue a system reset, ensuring that the system can return to a stable operating state.

With a wide operating temperature range and packaged in a 16-pin SOIC, the MAX691AEWE is suitable for a variety of applications, including computers, controllers, intelligent instruments, and critical µP power monitoring. Its features are summarized as follows:

• Reset Output Guaranteed to V<sub>CC = 1V
• Automatic Backup Battery Switchover
• Watchdog Timer to Ensure System Integrity
• Power-Fail Comparator to Monitor Power Failures
• Minimum Component Count with No External Components Necessary
• Low Supply Current of 50µA (Typical)
• Wide Operating Temperature Range

Designed for versatility, the MAX691AEWE supervisory circuit is a reliable choice for system designers looking to enhance system reliability and reduce the risk of system failure due to power issues or software errors. Maxim Integrated's commitment to quality ensures that the MAX691AEWE meets the stringent requirements of modern electronic systems.