S32K144 ADC channel collet

[547416104]

Hello EveryOne,

I just config AD00 and AD01, AD112,AD113 channels to do ADC collect, but I find the AD00 channel ADC value  is affected by AD01, AD112 is affected by AD113, whether I config is wrong, thanks

[VaneB]

Hi @547416104 

The S32K1's ADC has three main sub-blocks:

• capacitive DAC
• comparator
• SAR

DAC is the most susceptible to the variations it can cause because it is designed with binary weighted capacitor arrays.

At the moment when you are using several channels of an ADC, the capacitors cannot be fully discharged when another measurement is already being made. I suggest you to set a delay between measurements to let the capacitors discharge.
Also, take a look to this application note and community post, it will be useful for you.

S32K1xx ADC guidelines, spec and configuration 

16-bit SAR ADC calibration 

B.R.

VaneB