ADM8323

The ADM8323/ADM8324 are supervisory circuits that monitor power supply voltage levels and code execution integrity in microprocessor-based systems. An on-chip watchdog timer checks for activity within a preset timeout window. A reset signal can also be asserted by an external push-button switch through a manual reset input. The RESET output is either push-pull (ADM8323) or open-drain (ADM8324).

A watchdog failure results in a low output on the RESET pin. A failure can be triggered either by a fast watchdog error (watchdog pulses too close together) or by a slow watchdog error (no watchdog pulse within the timeout period). This effectively gives a window to observe the watchdog pulse. The watchdog timeout is measured from the last falling edge of the watchdog input (WDI). There are eight different watchdog windows available, as shown in Table 5.

Each device is available in a choice of 26 reset threshold options from 2.5 V to 5 V in 100 mV increments. There are also four reset timeout options of 1 ms, 20 ms, 140 ms, and 1120 ms (minimum). Not all device options are available as standard models. See the Ordering Guide for details.

The ADM8323/ADM8324 are available in a 5-lead SOT-23 package and typically consume only 10 μA, making them suitable for use in low power portable applications.

Applications

• Automotive
• Microprocessor systems
• Computers
• Controllers
• Intelligent instruments
• Portable equipment