SAADC pulls too much current

RE: SAADC pulls too much current

Kazi Afroza Sultana — Tue, 08 Nov 2022 14:33:53 GMT

Great that you have found the cause. Could you please share this briefly with the community?

RE: SAADC pulls too much current

dkhayes117 — Tue, 08 Nov 2022 11:59:54 GMT

After further inspection, I believe the dev board I'm using has a design flaw with their battery measurement circuit which is causing the power discrepancy.

RE: SAADC pulls too much current

Kazi Afroza Sultana — Mon, 31 Oct 2022 14:30:29 GMT

Hello,

We do not support RUST.

You have your own ADC drivers, so we require much more information as it seems there are hardware issues.

"I have an off-board hall effect sensor that I will sample on one channel. When that sensor is connected to an AIN pin, the sleep current drops to 115 uA. I don't understand why this happens, even when the sensor isn't powered on.".

If the current consumption drops when you connect a signal to an analog pin, there must have something wrong with the HW. Are you using our DK? If it is not our DK, can send us the schematics and layout.

You can read out the state of the SAADC registers after init and deinit and send us.

Thanks.

BR,

Kazi Afroza Sultana

RE: SAADC pulls too much current

dkhayes117 — Fri, 28 Oct 2022 14:25:39 GMT

Below is the API

https://github.com/embassy-rs/embassy/blob/master/embassy-nrf/src/saadc.rs

My code

// Configuration of ADC, over sample to reduce noise (8x)
let mut adc_config = Config::default();

//Oversampling only works for a single channel configuration
// adc_config.oversample = Oversample::OVER8X;

let sensor_channel = ChannelConfig::single_ended(&mut p.P0_14);
let bat_channel = ChannelConfig::single_ended(&mut p.P0_20);
let mut adc = Saadc::new(
    p.SAADC,
    interrupt::take!(SAADC),
    adc_config,
    [sensor_channel, bat_channel],
);

RE: SAADC pulls too much current

Kazi Afroza Sultana — Fri, 28 Oct 2022 14:09:26 GMT

Hello,

We need few information about your code showing how you are using the SAADC, what function you are calling and what API you are using.

Thanks.

Best Regards,

Kazi Afroza Sultana