High current consumption with LPCOMP enabled

[GiulianoFranchetto]

Hi,

I'm currently testing LPCOMP with one of our nRF5340DK boards.

The power consumption of the LPCOMP seems way too big (around 140µA) once enabled with this conf:

nrfx_lpcomp_config_t config = {
		.hal    = {NRF_LPCOMP_REF_SUPPLY_2_8,
			   NRF_LPCOMP_DETECT_CROSS,
			   NRF_LPCOMP_HYST_NOHYST},
		.input  = (nrf_lpcomp_input_t) NRF_LPCOMP_INPUT_2,
		.interrupt_priority = NRFX_LPCOMP_DEFAULT_CONFIG_IRQ_PRIORITY
	};

The 140µA are from the LPCOMP alone, as there is no other functionnality enabled on that board (no CONFIG_LOG, no CONFIG_SERIAL ...)

If I #if 0 ... #endif all my code, the current consumption drops to < 10µA.

Is there a errata on the LPCOMP that could explain such large current consumption?

Can we reduce it programmatically?

Regards

Giuliano

[Edvin]

Hello,

What current consumption do you see on the LPCOMP? Can you please share the project that you use to measure the current consumption (the one containing the #if condition)? So that I can easily reproduce this and measure it?

BR,

Edvin

[GiulianoFranchetto]

Hello,

As said, I can measure an increase of 140µA when enabling LPCOMP, which seems like a lot.

I've attached the project with my answer.

lpcomp_test.zip

Regards

Giuliano

[GiulianoFranchetto]

Hi Edvin,

Any news on that subject?

Did you reproduce the issue?

Regards

Giuliano

[Edvin]

Hello Giuliano,

I have done the same measurements as you have done, and I see the same behavior. I don't why this is happening. I will try to speed up the process to figure out why it is drawing so much power. I agree that it is more than the expected amount.

Just while I ask around. Are you using a DK? If so, what version do you have? (I am testing on a 0.10.0 version).

[GiulianoFranchetto]

Hi Edvin,

We are indeed using the nRF5340 PDK.

I can't find a more specific version printed on the PCB.