Maxim Integrated MAX805LCPA+ Microprocessor Supervisory Circuit

The MAX805LCPA+ from Maxim Integrated is a highly reliable and efficient 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 conjunction with +5V-powered circuits.

This device significantly improves system reliability by providing several key supervisory functions, including a reset output during power-up, power-down, and brownout conditions. The reset signal ensures that the µP starts in a known state. The MAX805LCPA+ generates a reset signal whenever the VCC supply voltage declines below a preset threshold, keeping it asserted for at least 140ms after VCC has risen above the reset threshold. This feature is crucial in preventing system errors and data corruption during unpredictable power incidents.

The MAX805LCPA+ also features a manual reset input that allows the user to initiate a system reset with an external pushbutton or logic signal. This manual reset is debounced and guarantees a clean reset pulse to the system.

Another notable feature of the MAX805LCPA+ is its watchdog timer, which monitors the system for software lock-up or other malfunctions. If the system fails to provide a watchdog edge within the watchdog timeout period, the MAX805LCPA+ issues a system reset, ensuring proper operation and recovery from fault conditions.

Designed for versatility, the MAX805LCPA+ comes in an 8-pin PDIP package and operates over a wide temperature range of -40°C to +85°C, making it suitable for various applications, including computers, controllers, intelligent instruments, critical µP and µC power monitoring, and portable/battery-powered equipment.

With its combination of reset logic, manual reset capability, and a watchdog timer, the MAX805LCPA+ from Maxim Integrated provides a comprehensive solution for system stability and is an essential component for any robust digital system design.