ADM8698/ADM8699 is a microprocessor supervisory circuit produced by Analog Devices, which has power supply monitoring and watchdog timing functions, and can send reset signal to the microprocessor when the 5 V VCC power supply is not sufficient.
The ADM8698 and ADM8699 are supervisory circuits that monitor a 5 V power rail and generate a reset pulse during power‑up, power‑down, or brown‑out conditions. The ADM8698 provides a reset output, while the ADM8699 adds a watchdog timer input to detect microprocessor activity and generate a reset if the watchdog is not serviced.
Both devices are offered in 8‑pin DIP, 8‑pin SOIC, and 16‑lead SOIC packages, with the larger package providing additional reset and watchdog output pins. Electrical specifications include a 3.0‑5.5 V operating voltage range, low supply current, and a guaranteed reset threshold of 4.65 V with 40 mV hysteresis.
| VCC Operating Voltage Range | 3.0 V – 5.5 V |
|---|---|
| Supply Current | 70 µA – 100 µA |
| Reset Voltage Threshold | 4.65 V typ |
| Watchdog Timeout Period (ADM8699) | 1.0 s – 2.25 s |
| Operating Temperature Range | -40 °C to +85 °C |
It monitors VCC from 3.0 V up to 5.5 V.
The reset output remains low for a minimum of 140 ms after VCC rises above the threshold.
The watchdog timeout period ranges from 1.0 s to 2.25 s.