General Description

The MAX6369–MAX6374 are pin-selectable watchdog timers that supervise microprocessor (µP) activity and signal when a system is operating improperly. During normal operation, the microprocessor should repeatedly toggle the watchdog input (WDI) before the selected watchdog timeout period elapses to demonstrate that the system is processing code properly. If the µP does not provide a valid watchdog input transition before the timeout period expires, the supervisor asserts a watch dog (WDO) output to signal that the system is not exe

cuting the desired instructions within the expected time frame. The watchdog output pulse can be used to reset

the µP or interrupt the system to warn of processing errors.

Features

♦ Precision Watchdog Timer for Critical µP Applications

♦ Pin-Selectable Watchdog Timeout Periods

♦ Pin-Selectable Watchdog Startup Delay Periods

♦ Ability to Change Watchdog Timing Characteristics Without Power Cycling

♦ Open-Drain or Push-Pull Pulsed Active-Low Watchdog Output

♦ Watchdog Timer Disable Feature

♦ +2.5V to +5.5V Operating Voltage

♦ 8µA Low Supply Current

♦ No External Components Required

♦ Miniature 8-Pin SOT23 Package