i.MX93 SAR ADC VREF value

[NZP]

Hello experts,

I am working on i.MX93 ADC and trying to read ADC using cortex-m33 mcu. In that I have checked almost all the registers related to ADC but unable to find Vref selection or configuration related register. 

1. Here what I want to know is that what is the voltage value of my Vref ?

2. How this Vref is selected by ADC, is there any dedicated register available to set Vref ?

P.S: I am able to read ADC value from PCDR register but just confusion is that how vref is selected by ADC.

[JorgeCas]

Hello,

Vref = VDD_ANAx_1P8.

The range is from 1.71 V to 1.89 V.

Best regards.

[NZP]

Hi JorgeCas,

Thanks for comment.

1. Does it mean that I don't need to any configuration related Vref in my coretx-m33 driver code. right? ADC will automatically derive VREF from VDD_ANAx_1P8?

[JorgeCas · Accepted solution]

Hello,

Yes, that it correct.

To use SAR ADC, a calibration/self-test must be performed after every power-up reset. This will check the supply voltage, reference voltage and calibrated values to warranty a correctly functionality.

Best regards.