GENERAL DESCRIPTION
The ADM6821-ADM6825 are supervisory circuits which monitor power supply voltage levels and code execution integrity in microprocessor-based systems. As well as providing power-on-reset signals, an on-chip watchdog timer can reset the microprocessor if it fails to strobe within a preset timeout period. A reset signal can also be asserted by means of an external push-button, through a manual reset input. The three parts feature different combinations of watchdog input, manual reset input and output stage configuration, as shown in table 1.

FEATURES
   Precision Low Voltage Monitoring down to 1.8V
   9 Reset Threshold Options:
      1.58V to 4.63V
   140ms (Min) Reset Timeout
   Watchdog Timer with 1.6s Timeout
   Manual Reset Input
   Reset Output Stages
      Push-Pull Active-Low
      Open-Drain Active-Low
      Push-Pull Active-High
   Low Power Consumption (3µA)
   Guaranteed Reset Output valid to VCC=1V
   Power Supply Glitch Immunity
   Specified from -40°C to +125°C
   5-Lead SOT-23 Package

APPLICATIONS
   Microprocessor Systems
   Computers
   Controllers
   Intelligent Instruments
   Portable Equipment