Hi,
I want to measure the current draw of the MCU only on the nRF52840DK while I am running my custom code. I want to exclude the current draw of all components except for the nRF52840 itself from my current measurement.
I am using a power analyzer (Otii Arc) for this test. It is connected to P21 and supplies 3.3VDC.
Can you please let me know the correct switch and connector setup for this test? I found many similar questions in DevZone regarding this, but many contradict each other and I wasn't able to decipher the schematics to get to a conclusion.
I tried 2 setups:
In setup 1; SW6 is set to nRF ONLY, SW10 is OFF, SW9 is VDD.
I get the below current draw for this setup, where the first part of the trace is for BLE Advertising, and second (more attenuated) part is for when BLE is connected. Average current draw during advertising is 138uA, and during connected state it is 86uA.
In setup 2; SW6 is set to nRF ONLY, SW10 is ON, SW9 is VDD, and a USB cable is connected to J2 which is connected to a PC on the other end.
In this setup, I get 132uA average during advertising mode, and 82uA during connected state.
The current draw measurements seemed quite low to me, but I can connect to the device successfully over BLE using the nRF Connect for Mobile app and read/write characteristics.
