I have a microcontroller (Arduino-like IoT device) and would like to connect a low power external hardware watchdog to be able to recover from failures. I know that a software watchdog is already incorporated, but it's just not sufficient in this case.
The requirements are:
- WD's output to start on "on" state and be able to stay in this state for at least one day in the absence of external trigger.
- If it receives a high signal from the microcontroller, it should reset (i.e. extend the "on" state for another day).
- If it doesn't receive a high signal from the microcontroller within the predefined time period (e.g. one day), it should timeout and switch its output to "off" for at least 10 seconds.
- It would be nice if the on and off periods are configurable (hardware-wise, e.g. through a potentiometer).
- Operation voltages 2-6V.
- Price does matter, as it's for a relatively cheap IoT microcontroller.
To give an example of what I'm trying to achieve, the best solution that I've come across that should cover my needs is this one: https://www.ebay.com/itm/DC-3V-24V-automatic-re-trigger-cycle-delay-time-timer-switch-module-max-20days/303098128782 (unfortunately, it exhibits instabilities and even worse the IC on it is not labeled).