MCU Temperature Reading Errors

[dluks]

We use a PIT and DMA to scan a number of ADC channels ever ms on a KV31. The ADC clock is 10 Mhz (MCU clock divided by 8). On occasion, post a reboot, the single ended temperature reading from ADC0 will be stuck at 25 C or on rare occasion report roughly 10 C below the actual measured temperature. All other voltages on that ADC appear to be normal.

Has anyone had an issue like this?

Thanks,

Dave

[miduo]

Hello,

Have you done anything of ADC Calibration? As the manual mentioned:

The ADC contains a self-calibration function that is required to achieve the specified accuracy.

Calibration must be run, or valid calibration values written, after any reset and before a conversion is initiated.