ADC reading stability with nRF52840

RE: ADC reading stability with nRF52840

Hieu — Tue, 04 Jun 2024 13:07:43 GMT

Hi Arun,

[quote user="ArunRuchir"]If you can guide me towards any sample Code, for Temperature monitoring or Battery Voltage monitoring with SAADC calibration, I will try tht and see if it helps. [/quote]

Please take a look at the Battery Voltage Measurement sample.

For a reference on how to setup the voltage-divider node, please refer to the Thingy:53 board file and its schematic.

Regards,

Hieu

RE: ADC reading stability with nRF52840

ArunRuchir — Tue, 04 Jun 2024 05:58:40 GMT

Thanks Hieu,

1) The VCC is provided via external Power source. No Battery.

2) SAADC neevr recalibrated, though temp change is indeed more than 10 Degree at our site.

However, I don't think this still justify the large amount of changes taking place in the values.

If you can guide me towards any sample Code, for Temperature monitoring or Battery Voltage monitoring with SAADC calibration, I will try tht and see if it helps.

I am using OpenThread to pass the values to an external data logger - just FYI.

Regards

Arun

RE: ADC reading stability with nRF52840

Hieu — Mon, 03 Jun 2024 19:44:52 GMT

Hi ArunRuchir,

There could be a couple of factors at play here.

How is VCC provided? If it is a battery source, then over the course of a few days, battery drain, temperature changes, and the circuit's load all can affect the voltage.
Is SAADC recalibrated regularly? Over the course of a few days, temperature could have changed, making recalibration necessary.
For more information about the need to recalibrate, refer to the SAADC documentation.

Hieu