RE: Power profiler regulates DK pin to 1.5V

youti — Fri, 21 Feb 2020 09:43:34 GMT

Hi Stian! The ppk is the nRF6707 and the development kit is PCA10040. With the USB it works better, I indeed managed to forget about it. Still, it doesn't work as intended. We tested it again on two DKs, with the ppk mounted on top and as external device. With these setups, the the results are different. To the DKs we uploaded the ble_app_beacon and the results are as below. The first plot shows the ppk on top of the DK, with SW2 set to DK of course. The second plot shows the plot when connecting the DK to the ppk via external DUT and P20 on the DK. We also connected the DK to the same supply as the ppk to see what happens, this is the third plot. As you can see there is still a small offset that I believe shouldn't be there.

RE: Power profiler regulates DK pin to 1.5V

Stian Røed Hafskjold — Thu, 20 Feb 2020 12:04:33 GMT

Hi, I will try out your setup here. Which PPK and DK version are you using?

Did you connect a USB cable to the PPK? Seems like this is needed when using the external regulator mode.

Are you plugging the PPK on top of the DK? In general it is better to keep the DK and PPK separated and power the DK from the DUT output header. Then you don't have to connect the external supply to both the DK and the PPK, which I'm thinking can cause problems. You must isolate the chip on the nRF52 DK so you don't power the atmega chip. You can try to power directly on the VDD nRF domain on P20 from the PPK.