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