Using WDT as a Temp Sensor?

[Archilochus]

Looks like an interesting project. The PBP code should not be difficult to write - remember to disable PBP's automatic watchdog timer clearing function (and then to clear the WDT as needed elsewhere in your code).

Calibrating the setup without a controlled temperature environment seems like it will be rough.
Some of the charts in the app note show a pretty bad deviation at around +30°C, not a good sign as far as reliability goes.

Also - Microchip says:

The linearity of the WDT is not guaranteed, but has been observed.

Not very encouraging. How about the TCxx series of temp sensors from Microchip instead?

Arch