Microprocessor Supervisor , Adjustable Reset and Watchdog Periods

The ADM691A/ADM693A/ADM800L/ADM800M family of supervisory circuits offers complete single chip solutions for power supply monitoring and battery control functions in microprocessor systems. These functions include mP reset, backup-battery switchover, watchdog timer, CMOS RAM write protection, and power-failure warning. The family of products provides an upgrade for the MAX691A/93A/800M family of products.

All parts are available in 16-pin DIP and SO packages. The ADM691A is also available in a space-saving TSSOP package. The following functionality is provided:

* Power-on reset output during power-up, power-down and brownout conditions. The circuitry remains operational with VCC as low as 1 V.

* Battery backup switching for CMOS RAM, CMOS micro-processor or other low power logic.

* A reset pulse if the optional watchdog timer has not been toggled within a specified time.

* A 1.25 V threshold detector for power fail warning, low battery detection, or to monitor a power supply other than +5 V.

* Low Power Consumption

* Precision Voltage Monitor

* ±2% Tolerance on ADM800L/M

* Reset Time Delay—200 ms, or Adjustable