topic Re: S32K358 measuring internal junction temperature in S32K

S32K358 measuring internal junction temperature

YAlex — Mon, 08 Sep 2025 19:10:58 GMT

I am attempting to measure junction temperature on an S32K358 mcu following this thread:
https://community.nxp.com/t5/S32K/Internal-Temperature-sensor/td-p/1688673

The problem I am having is that the measured temperature seems to have different units than expected. Based on available documentation, it appears I should be measuring temperature in degrees C. However, at room temperature I'm measuring on the order of 225 instead of 22.

I have run the initialization of the ADC per the examples. I run the calibration, then enable the temp sensor.

The collection routine is as follows:

I convert from fixed precision to degrees C as follows:

Based on this, should I expect to red temperature in units of degrees C?

Re: S32K358 measuring internal junction temperature

_Leo_ — Mon, 08 Sep 2025 22:21:37 GMT

Thank you for your interest in our products and for contributing to our community.

Please refer to the following knowledge base post:

https://community.nxp.com/t5/S32K-Knowledge-Base/Example-S32K344-TempSenser-S32DS36-RTD600-500-400-p24/ta-p/2136187

I hope this information is helpful.

Re: S32K358 measuring internal junction temperature

YAlex — Tue, 09 Sep 2025 21:59:11 GMT

Thank you

To add some context, I am using the S32K3X8-EVB

J23 by default is in the 1-2 position, which selects 5V on VREFH, and I was using 53 (3.3V) for TempSense Voltage Supply.