CC2540/1 ADC internal reference as input channel

Mark Bianchi1

Is it possible to select the internal voltage reference as an input to the ADC and use AIN7, AIN6-AIN7, or AVDD5 as the reference? Channel 13 is listed as reserved, however in the BLE stack the hal_adc.h shows channel 13 as Vref.

It would be hugely useful if this configuration is possible. This would provide a way to calibrate the voltage reference. As well as enabling high-side voltage measurements that don't need resistive dividers to bring the measurements down to the reference level.

I'm guessing if this is possible it is undocumented and totally not supported.

-Mark

over 10 years ago

0 YiKai Chen over 10 years ago

Guru 735685 points

Yes, you can use HalAdcSetReference(HAL_ADC_REF_125V ); to set ADC to use internal reference.

0 Mark Bianchi1 over 10 years ago in reply to YiKai Chen

Intellectual 300 points

I am asking if the internal reference can be used as an input, not as the reference. I would like to be able to use an external voltage as the reference and then perform and ADC measurement of the internal reference as if it were a DC voltage input.

0 YiKai Chen over 10 years ago in reply to Mark Bianchi1

Guru 735685 points

Sorry for my misunderstooding. As I know, there is no such capability on CC254x.

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CC2540/1 ADC internal reference as input channel