The MAX823/MAX824/MAX825 are microprocessor (μP) supervisory circuits from MAXIM that combine reset output, watchdog, and manual reset input functions in 5-pin SOT23 and SC70 packages. They significantly improve system reliability and accuracy compared to separate ICs or discrete components. The MAX823/MAX824/MAX825 are specifically designed to ignore fast transients on VCC. Seven preprogrammed reset threshold voltages are available (see Reset Threshold Table). All three devices have an active-low reset output, which is guaranteed to be in the correct state for VCC down to 1V. The MAX823 also offers a watchdog input and manual reset input. The MAX824 offers a watchdog input and a complementary active-high reset. The MAX825 offers a manual reset input and a complementary active-high reset. The Selector Guide explains the functions offered in this series of parts.
The MAX823, MAX824, and MAX825 are 5‑pin microprocessor supervisory circuits that provide reset output, watchdog timer, and manual reset input functions. They are offered in SOT‑23 and SC70 packages and are designed to improve system reliability by monitoring power‑supply conditions and processor activity.
Key features include seven selectable reset‑threshold voltages, an active‑low reset output guaranteed down to 1 V, a 1.6 s watchdog timeout, and optional manual reset input. The devices are suited for embedded controllers, automotive systems, portable equipment, and other applications requiring precise power‑monitoring and reset control.
| Operating current (MAX823L/M) | 6 µA |
|---|---|
| Operating current (MAX825T/S/R/Z/Y) | 2 µA |
| Watchdog timeout period | 1.6 s |
| Power‑on reset guarantee | Valid down to VCC = 1 V |
| Operating temperature range | -40 °C to +85 °C (up to +125 °C for some packages) |
The watchdog timer has a timeout of 1.6 seconds.
Each device is a 5‑pin supervisory circuit.
They operate from –40 °C to +85 °C, with some versions rated to +125 °C.