Power usage nRF52840 and nRF9160dk, BLE

RE: Power usage nRF52840 and nRF9160dk, BLE

Jared — Wed, 01 Jun 2022 10:02:53 GMT

Hi Sarah,

Calling CONFIG_SERIAL=n would disable the UART interface that is used for communicating with the hci_lpuart that is running on the nRF52840. I think that you should also add the LPUART implementation on the nRF9160 side for it work properly.

[quote user=""]. At the moment I measure on the 'nRF current measurement'-pins[/quote]

These pins only measure the current consumption of the nRF9160, not the nRF52840 included.

Can you share your entire prj config file?

regards

Jared

RE: Power usage nRF52840 and nRF9160dk, BLE

Sarah Loos — Wed, 25 May 2022 16:49:18 GMT

Hey Jared

Sorry for the confusion!

hci_lpuart is running on nrf52840 and the peripheral hr is running on the nrf9160d. This works!! (I added the 4 lines in my config-file and in the devicetree I changed some settings). The messages that are sent every second over BLE arrive on my phone (via nrf connect for mobile I can see the incoming messages) and I can see the current rising every second. So the program works.

But now I want to reduce the power consumption. To reduce the nrf9160-current, I added CONFIG_UART_CONSOLE=n to the nrf9160dk config-file.
(I already worked with nb-iot and then it worked)

Considering it worked before with an nb-iot program on the nrf9160, the consumed power is caused by the nrf52840? Is there a way to get this reduced?

Hope this gives a clearer picture.

Sarah

RE: Power usage nRF52840 and nRF9160dk, BLE

Jared — Wed, 25 May 2022 08:42:00 GMT

Hi,

[quote user=""]I combine the hci_lpuart on the nRF52840 and a program that uses BLE on the nRF9160 on the nRF9160dk.[/quote][quote user="SarahL"]The code is built up as follows: peripheral hr is changed so it can be flashed on the nrf9160 chip (lpuart on the nrf52840) with [/quote]

I'm a bit confused on what example that runs on each chip. The nRF9160 DK has a onboard nRF52840 which supports BLE and a nRF9160 which supports LTE. The latter does not support BLE, flashing the peripheral HR example to the nRF9160 does therefore not make sense unless you meant the onboard nRF52840. If you meant the nRF52840, what is running on the nRF9160?

The Online Power Profiler user guide contains useful tips for reducing the current on the nRF9160.

regards

Jared

RE: Power usage nRF52840 and nRF9160dk, BLE

Sarah Loos — Tue, 24 May 2022 12:16:22 GMT

I'm measuring with a Joulescope (so not the PPK 2) and I use the nRF measurement pins (J22 in this case). The picture shows the measurement, after 24 seconds, my phone connected with the nRF.

The code is built up as follows: peripheral hr is changed so it can be flashed on the nrf9160 chip (lpuart on the nrf52840) with

CONFIG_UART_2_ASYNC=y

CONFIG_UART_2_INTERRUPT_DRIVEN=n

CONFIG_UART_2_NRF_HW_ASYNC=y

CONFIG_UART_2_NRF_HW_ASYNC_TIMER=2

in de config-file and (if I understand correctly) pin 17 and 18 are the rx- and tx-pin of uart2 to connect nrf52840 and nrf9160 with each other.

Kind regards

RE: Power usage nRF52840 and nRF9160dk, BLE

Jared — Tue, 24 May 2022 11:01:16 GMT

Hi,

Can you share your code and describe how you are measuring the current? Are you using the PPK 2? Can you share a screenshot of the current plot from the Power profiler?

regards

Jared