I was using the ADC standard channel of S32K312 to sample the voltage and found that the maximum difference between the result and the real value can reach 6LSB. I think there may be something wrong with my sampling configuration:
The CORE clock is 120MHz, the sampling clock and calibration clock of ADC is 4, and the sampling time configuration is 255, enabling high-speed mode.
Even if I refer to the configuration on the manual, and the result is similar.