GENERAL DESCRIPTION

The ADM823/ADM824/ADM825 are supervisory circuits that monitor power supply voltage levels and code execution integrity in microprocessor-based systems. In addition to 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 an external pushbutton, 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 2.5 V to 5 V power supply monitor
7 reset threshold options: 2.19 V to 4.63 V
140 ms (minimum) reset timeout
Watchdog timer with 1.6 sec timeout (ADM823, ADM824)
Manual reset input (ADM823, ADM825)
Push-pull output stages
RESET (ADM823)
RESET, RESET (ADM824/ADM825)
Low power consumption: 5 μA
Guaranteed reset output valid to VCC = 1 V
Power supply glitch immunity
Specified over automotive temperature range
5-lead SC70 and SOT-23 packages

APPLICATIONS

Microprocessor systems
Computers
Controllers
Intelligent instruments
Portable equipment