NRF52811-CAAA ADC Input pins

[Kaveh.M]

Hi, 

In nRF52811-CAA chip, which pins are allocated to ADC inputs. In Table 122 of datasheet which shows pinout for WLCSP package, it just mentions AIN1, AIN2, and AIN3. 

Are there just 3 ADC inputs available on this chip? It seems there should be 8 ADC channels available. 

Please advise.

Thanks

[Simonr]

Hi

The nRF52811 WLCSP chip indeed only as 3 dedicated SAADC inputs, so ADC will be a bit limited on the WLCSP package. But, there are two more analog pins available in P0.00 and P0.01 if you don't use these pins for the external LF crystal. It's up to you whether you want to use these or not on your end.

Best regards,

Simon

[Kaveh.M]

Thanks. I am not using LF crystal pins as they dont seem to be mandatory. I just use HF crystal. 

So you mean I can allocate P0.00 and P0.01 also as ADC inputs? Aside from the other 3 available ADC pins on P0.03, P0.04, P0.05.

[Simonr]

Yes, these are analog pins as well. As long as you set the LF clock source to the RC or SYNTH instead these pins will be available as GPIOs.

Best regards,

Simon