Can't go to Sleep after NRF_SAADC->TASKS_SAMPLE

[md9981]

Hello,

we have a problem using the SAADC module with the low power mode, particularly after execution of the NRF_SAADC->TASKS_SAMPLE task.

Before taking a sample, the current consumption in lower power mode is around 2.3 uA. After sampling and disabling the SAADC module the current consumption stays at 460 uA in low power mode and can only be reverted to 2.3 uA after a reset. What could be causing this behavior?

We're using the nrf52832 Chip with the s132 Softdevice.

[AmbystomaLabs]

The saadc is supposed to turn off after a sample. But based on the blogs this might not be true for all conditions and all version of S132.

My feeling is safer to just turn it off when you are done with it. Then re-init next time you use it.

To turn it off:

nrf_drv_saadc_uninit();
NRF_SAADC->INTENCLR = (SAADC_INTENCLR_END_Clear << SAADC_INTENCLR_END_Pos);
NVIC_ClearPendingIRQ(SAADC_IRQn);

[md9981]

It was the PAN-28 issue, then taking a Sample with scan-mode enabled, it wouldn't be possible to go under the 460uA in low power mode.

Only enabling one ADC channel at a time to take a sample solved this Problem for me and the current consumption dropped to 2.3uA.

[liu_zhixiang]

Hi, can you help me solve this question.https://devzone.nordicsemi.com/f/nordic-q-a/36246/saadc-sample-cant-use-with-sd_power_system_off