简单锁定看门狗定时器

摘要：基于对μP-supervisor/watchdog IC （ MAX6749 ） ，该电路在输入脉冲流的损失提供了一个锁定的失效指示。该电路可以监控风扇（根据风扇的转速输出） ，一个振荡器，或微处理器的软件执行。

Maxim > App Notes > Circuit protection Microprocessor supervisor circuits
Keywords: watchdog timers, latched watchdog timers, microprocessor supervisors Jan 05, 2011

APPLICATION NOTE 4558
Simple Latching Watchdog Timer
By: Eric Schlaepfer, Applications Engineer


Abstract: Based on a P-supervisor/watchdog IC (MAX6749), this circuit provides a latched failure indication in response to a
loss of the input pulse stream. The circuit can monitor a fan (based on the fan's tachometer output), an oscillator, or the software
execution of a microprocessor.

A similar version of this article appeared in the April 2007 issue of Power Electronics Technology magazine.

Most watchdog-timer ICs produce a single, limited-duration output pulse when the watchdog time