NRF52DK power consumption with demo UART

[Maxim]

Hi, I am currently working to measure power consumption on a custom board and I found huge power consumption while advertising (BMD-300 1.15mA DCDC enabled).

So I have tried to do the measurement on my NRF52DK to see if there is any difference with the following procedure:

• Cut the SB9 trace
• bypass the diode with a short circuit on SB12
• Power the board with the provided coin cell

The full procedure is described Here

The program loaded on the NRF52 is ble_app_uart_pca10040_s132.hex directly provided by the nRF5_SDK_12.1.0_0d23e2a.zip. The program is loaded with nRFgo Studio.

And I measure:

1. -On advertise + Led1 blink: 2.85mA/3.05mA
2. -Connected + Led1 ON: 2.29mA
3. On sleep + Led1 OFF: 2.20µA

So my question is this normal to have so much power consumption on the NRF52DK or is my measurement are biased by my multimeter (Metrix Mtx 3281)

Thanks you for your answers !

[Matt]

Can you cross check the figures in 23.15.2 Radio current consumption (transmitter) and in 23.15.3 Radio current consumption (receiver) in the "nRF52832 Product Specification v1.1"?

[Maxim]

I have already read these figures, but i think my problem is the prescision of my measurements. I think my problem is my multimeter or my calculations, i'have found this interresting tutorial: Calculating average current from Oscilloscope and Ampere meter measurements avaible Here.

The average current on adv mode seems to be the same i have measure by myself (2.48mA/2.85mA), so the real consumption is much lower according to these calculations (~13µA).

So do you think this issue is due to the low frequency sampling of my multimeter or my method of measurement.

[Matt]

I'm more of a firmware dude... you need to consult the Nordic current measurement experts here :(

[Maxim]

Ok, no problem, thanks anyway !

[Bjørn Kvaale]

I'm guessing you don't happen to have a Nordic Power Profiling Kit (PPK) at your disposal? Which code are you trying to run? Could you try to run the ble_app_hrs example under ble_peripheral from SDK 14 and see what your current consumption is then? I'll try the same thing using the PPK and we can compare results.