NRF52832 DK --PCA10040 current measurement

RE: NRF52832 DK --PCA10040 current measurement

Stian Røed Hafskjold — Wed, 04 Aug 2021 21:58:30 GMT

Hi, I tried it out here, and it looks like the PPK1 is not working well with the newest software updates. I get the same noise and about 100uA in system OFF mode. I checked with a power analyzer and it looks normal, so it's definitely something wrong with PPK1. I will have to check with the developers. Sorry for the inconvenience. I would recommend to get the PPK2, as the PPK1 is now a deprecated product.

RE: NRF52832 DK --PCA10040 current measurement

Astor — Tue, 03 Aug 2021 08:44:27 GMT

The application performs normally no matter it's connected to PPK or not (press button and starts advertising). But the current doesn't meets expectation.

I'm using PPK1 exactly same as described in user guide(perhaps):

RE: NRF52832 DK --PCA10040 current measurement

Stian Røed Hafskjold — Tue, 03 Aug 2021 08:37:26 GMT

Hi, is it working when you do not connect the PPK together with the DK? How do you connect the PPK, and are you using the PPK1 or PPK2?

RE: NRF52832 DK --PCA10040 current measurement

Astor — Tue, 03 Aug 2021 02:51:53 GMT

Hi, while testing with PPK, ble_app_pwr_profiling has great current and unknown behavior(without press any button now). Minimum current is about 160 uA.

I just connect PPK and DK together with SB9 cut. Softdevice version 7.2.0, SDK version 17.0.2

RE: NRF52832 DK --PCA10040 current measurement

Astor — Mon, 02 Aug 2021 13:41:22 GMT

Thank you Stian, I think I missed the step to leave the USB cable plugged in. Will follow your suggestion and test with ble_app_pwr_profiling.

Really helped, thanks alot

RE: NRF52832 DK --PCA10040 current measurement

Stian Røed Hafskjold — Mon, 02 Aug 2021 12:35:59 GMT

Yes, that's exactly what the ble_app_pwr_profiling is doing. It starts out in system OFF mode, so you can verify the measurement setup. Then you push button 1, and it will start advertising, waiting for a connection. It is meant for power profiling normal BLE applications.

The blinky app is not power optimized because it has logging enabled.

If you want to power the nRF52 DK from a SMU (source measure unit, i.e. advanced power supply, which provides stable voltage and measures the current through the power supply.) you will have to power the + wire on the current measurement header, P22, and the - wire on one of the GND connections. And, set the output voltage to match the DK voltage exactly. It should be around 2.7V. Also, leave the USB cable plugged in to power the rest of the board.

If you want to calculate the life time of your application, you can use the online power profiler

RE: NRF52832 DK --PCA10040 current measurement

Astor — Mon, 02 Aug 2021 12:21:04 GMT

Hi, will do later. FYI, we are develop a low power device that is advertising all day and awaits connection.

So we need to find out how long it can survive with battery. That's why we chose the blinky app.

We care nothing about System Off mode and all we will run is BLE + System ON mode.

So it will be really kindly of you to guide us directly how to measure the power consumption(current) with an advanced power supply, which provides stable voltage and measures the current through the power supply.

Thanks

RE: NRF52832 DK --PCA10040 current measurement

Stian Røed Hafskjold — Mon, 02 Aug 2021 11:58:46 GMT

Hi, can you try to run ble_app_pwr_profiling instead? It is power optimized and has logging disabled by default. It starts out in system OFF mode and you should see < 1 uA consumption.

Other than that, you need to make sure that logging is disabled in the examples you are running (NRF_LOG_ENALBED=0 in sdk_config.h)

Are you using PPK1 or PPK2? In ampere meter mode or SMU mode?

RE: NRF52832 DK --PCA10040 current measurement

Astor — Mon, 02 Aug 2021 09:25:29 GMT

BTW, I'm modifying ble_app_blinky project with comment out button_init and led_init.

Set DCDC enable and adv TX power to 0dBm