Is it possible to configure the IWDG timer to 30 minutes?

[Khoo.B]

I have an IoT hardware (using STM32L152) that carry out some tasks and go to STOP mode for 30 minutes. Then, it will wake up and repeat the same process again.

Now, I would like to add the watchdog timer to ensure everything works fine. My question is - can we set the countdown timer to 30 minutes? I have seen on other discussion that it is not possible to configure the watchdog timer to such a long period.

Any suggestions? Thank you very much!

[Tesla DeLorean]

I think you'll find the counter and prescaler are too small.

Think you have to use RTC Alarm(s)

[Jeroen3]

@Community member​ is right. Maximum 28 seconds.

[Khoo.B]

Ok, thanks for the suggestion. Would it be possible to turn it off?

I have seen in other discussions that an alternative work around is to wake up from the STOP mode every <28 seconds to reset the counter. Would this have a significant impact to the power consumption?

[AvaTar]

An once activated watchdog timer cannot be turned off.

For an application with 30 minutes sleep times, I would not consider a watchdog.

[Khoo.B]

What would you recommend in this case? An external watch dog?