Maxim Integrated's MAX691ACWE Microprocessor Supervisory Circuit

The MAX691ACWE from Maxim Integrated is a comprehensive microprocessor (µP) supervisory circuit designed to monitor power supplies and microprocessor activity in digital systems. It provides excellent circuit reliability and low cost by eliminating external components and adjustments when used in battery-powered systems, computers, controllers, intelligent instruments, and critical µP power monitoring applications.

This versatile device integrates a plethora of features to ensure the stable operation of the microprocessor under varying power conditions. The MAX691ACWE includes a precision voltage monitor, watchdog timer, µP reset, battery backup switching, and power-fail indicator, making it an all-in-one solution for system management and protection.

Key features of the MAX691ACWE include:

• Power Supply Monitoring: It ensures that the µP is only operating when power supply levels are within acceptable limits. If a brownout or power failure occurs, the MAX691ACWE automatically resets the µP to prevent erroneous operation.
• Watchdog Timer: The built-in watchdog timer keeps the µP system functioning correctly by monitoring the system activity. If the µP fails to strobe the watchdog within a preset time frame, the MAX691ACWE will issue a system reset, ensuring that the system can recover from a software lock-up or malfunction.
• Battery Backup: In the event of a power failure, the MAX691ACWE automatically switches to a backup battery to maintain volatile memory and real-time clock operations, providing seamless transition without data loss.
• Manual Reset: A manual reset feature allows for an external push-button to initiate a system reset, offering an additional layer of control for system operators.
• Power-Fail Warning: The device provides an early warning of impending power failure, allowing the system to execute shutdown procedures to prevent data loss or hardware damage.

The MAX691ACWE is provided in a 16-pin Wide SO package and is designed to operate over the industrial temperature range of -40°C to +85°C. Its integration of key supervisory functions makes it an excellent choice for enhancing system reliability and data integrity in critical applications.

Maxim Integrated's commitment to high-quality and high-performance circuitry is evident in the MAX691ACWE, making it a top choice for designers looking to bolster the operational stability of their microprocessor-based systems.