ADM698

a FEATURES Superior Upgrade for MAX698/MAX699 Guaranteed RESET Assertion with VCC = 1 V Low 0.6 mA Supply Current Precision 4.65 V Voltage Monitor Power OK/Reset Time Delay Watchdog Timer Minimum Component Count Performance Specified over Temperature APPLICATIONS Microprocessor Systems Computers Controllers Intelligent Instruments Automotive Systems Critical ␮P Power Monitoring VCC Microprocessor Supervisory Circuits ADM698/ADM699 FUNCTIONAL BLOCK DIAGRAM ADM698/ ADM699 RESET GENERATOR 4.65V RESET* RESET WATCHDOG INPUT WDI* WATCHDOG TRANSITION DETECTOR (1 sec) WATCHDOG OUTPUT WDO* *WDI (ADM699 ONLY) RESET (SOIC ONLY) WDO (ADM699 SOIC ONLY) TYPICAL APPLICATION CIRCUIT GENERAL DESCRIPTION +5V The ADM698/ADM699 supervisory circuits provide power supply monitoring and watchdog timing for microprocessor systems. The ADM698 monitors the 5 V VCC power supply and generates a RESET pulse during power up, power down and during low voltage “Brown Out” conditions. The RESET output is guaranteed to be functional (logic low) with VCC as low as 1 V. The ADM699 features an identical monitoring circuit as in the ADM698 plus an additional watchdog timer input to monitor microprocessor activity. The RESET output is forced low if the watchdog input is not toggled within the 1 second watchdog timeout period. Both parts are available in 8-pin plastic DIP and 16-lead SOIC packages. The 16-lead SOIC contains additional outputs RESET (without inversion) and Watchdog Output WDO (ADM699 only)....