ADC for Battery Measurement

[BLE_Full_Stack]

Hello All,

I need some urgent need regarding battery voltage

I am using 8 ADC Channel (ADC0 - ADC7) for different different purpose.( NRF_SAADC_INPUT_AIN0  to NRF_SAADC_INPUT_AIN7)

All ADC Channels are working in scan mode.

Now I want to calculate Battery Measurement.I have read that we can use NRF_SAADC_INPUT_VDD for that.

For that , do i need to free up any ADC channel?or NRF_SAADC_INPUT_VDD  is having any internal mechanism?

[Jørgen Holmefjord]

Hi,

NRF_SAADC_INPUT_VDD is threated like any other analog input. The SAADC have only 8 channels. If you are using all of them, you need to free one up in order to measure battery voltage using the SAADC.

Best regards,
Jørgen

[BLE_Full_Stack]

1. So if i am using all ADC in scan mode, then for battery measurement only , i have to start all ADC channels. Is it correct?

- so, on battery Notification interval , all channels should have to be scanned/run?

2. May i have different callback for battery service and other channels?

[Jørgen Holmefjord]

Yes, you need to enable other channels, or sample all channels (scan mode), and then only handle the enabled channels (or discard other channels than battery sample).

There is not support for multiple callback handler in the SAADC driver. I would recommend setting a flag when sampling the battery voltage and use this to run the correct code in the handler.