How to minimize the power consumption of QSPI flash on 52840DK?

RE: How to minimize the power consumption of QSPI flash on 52840DK?

Sigurd Hellesvik — Wed, 27 Oct 2021 11:17:25 GMT

Hi,

You are correct yes, the QSPI driver in Zephyr does not support DPD currently.

I believe this is fixed in pull request.
It is not merged yet however, so you will have to implement the changes yourself, or wait for it to be merged.

Regards,
Sigurd Hellesvik

RE: How to minimize the power consumption of QSPI flash on 52840DK?

Anthony Yuan — Wed, 27 Oct 2021 10:46:53 GMT

Hi,

I just tried using below west commands to build and flash DK1

west build -p -b nrf52840dk_nrf52840 -- -D OVERLAY_CONFIG=overlay-mtd-sed.conf -D CONFIG_LOCK=y

west flash --erase

And then do Homekit provision:

nrfjprog -f nrf52 --sectorerase ./provisioned_xxx-xx-xxx.hex

And then pairing with Apple Home App again.

The average current is still > 2mA.

Regards,

Anthony Yuan

RE: How to minimize the power consumption of QSPI flash on 52840DK?

Anthony Yuan — Wed, 27 Oct 2021 09:53:21 GMT

Hi,

Could you provide what version of the nRF52840DK? (number below the PCA10056 on the sticker)

-- The sticker says: PCA10056 1.0.0 2018.43

How do you build the project?

-- I am using Visual Studio Code's nRF Connect Plugin to Pristine build default multiprotocol sample and flash DK. I will use default west commands to pristine build/flash DK again and let you know how it works.

Regards,

Anthony

RE: How to minimize the power consumption of QSPI flash on 52840DK?

Sigurd Hellesvik — Wed, 27 Oct 2021 09:17:04 GMT

I am talking to our developers on what the problem might be.
They have two questions for you:

Could you provide what version of the nRF52840DK? (number below the PCA10056 on the sticker)

How do you build the project?

Regards,
Sigurd Hellesvik

RE: How to minimize the power consumption of QSPI flash on 52840DK?

Anthony Yuan — Wed, 27 Oct 2021 02:33:24 GMT

Hi Sigurd Hellesvik,

Thanks for your reply.

I checked the generated .config files for both application and mcuboot, now

# CONFIG_LOG is not set
# CONFIG_SERIAL is not set

And then I tested the same merged hex on 2 52840DKs:

DK1, cut SB16, short SB18 (use VDD_nRF instead of VDD_PER as the power source of the external memory)

DK2, short SB16, open SB18 (as default on DK, use VDD_PER as the power source of the external memory)

Both DKs are measured with PPK2 like this and switch the SW6 "nRF ONLY | DEFAULT" to "DEFAULT" on 52840DK

I think 52840 itself have proper current consumption but the external memory was not been set to DPD to save power.

Regards,

Anthony

RE: How to minimize the power consumption of QSPI flash on 52840DK?

Sigurd Hellesvik — Tue, 26 Oct 2021 11:16:29 GMT

Hi Anthony,

The even high power consumption is often related to the logging module or debugging.
So before we start looking at QSPI, lets just check:

Are you debugging? If so, try to measure without debugging.

Have you disabled logging? You can do this by setting the following:

CONFIG_LOG=n
CONFIG_SERIAL=n

Regards,
Sigurd Hellesvik