Why does ADC pin voltage jump in S32K1?

jingfang · ‎03-01-2023

Cusotmer use PTC2，PTC2 impending，the measured voltage will jump.

PTC2:ADC0_SE10/CMP0_IN5

Senlent · ‎03-01-2023

What is the specific part number? Is the hardware customer-made?
Without a circuit diagram, without sample code, we can't help your customer troubleshoot with just this picture.

Customers can try to disconnect the pins of the MCU and test the sampling point with an oscilloscope alone. If the phenomenon is still the same, the software problem can be ruled out first.

jingfang · ‎03-01-2023

FS32K146UAT0VLLT，the circuit diagram is as follows:,customer disconnects peripheral loop and test pin,there's a big voltage jump.customer connects peripheral loop and test pin,voltage jump still remain,but the jump becomes 1V.

Senlent · ‎03-02-2023

Hi@jingfang

According to the information you provided, I still cannot confirm the problem, and the circuit you provide is not complete.

Suppose the customer has disconnected from the connection of the TP610 to the MCU, please measure the front and back of the D600,If it is still similar to the waveform, then this requires the user's hardware engineer to check the hardware design or whether there is a problem during the welding process.

Is this a sampling circuit? What do you want to measure? If this is a sampling circuit, why add a diode?