PPK showing 80 mA on DK

[Konrad213]

Hi! 

I've been having some issues with the ppk recently. I've been trying to measure the current on our custom board but it was showing way too much so I tried on the DK. This is what I'm getting:

The higher baseline is just as soon as the ppk measurement starts and then goes away and consistently stays as it is on the right side of the image. I've tried switching out the DK and the PPK and nothing helped. Wondering if you know what the issue could be? I'm not 100% sure if it started after, but I recently upgraded the nrf connect firmware (don't remember exactly from which version but probably 3.3.X). 

[Simonr]

Hi Konrad

Thank you for the image upload and the confirmation of your setup. Do you have multiple PPKs behaving like this, or just the one? From the image, it does not look good, as a current draw of 80+ mA generally points towards something being defect on the PPK. Was it like this when you got it, or did it happen after some time of operation? Are you able to see any physical components missing on the PPK, or have you powered it with more than 3.6V at any point that might have damaged it? Can you please try to explain in detail what happened when/prior to the PPK when it started showing these values?

Best regards,

Simon

[Konrad213]

Thanks Simon, yeah it's probably due to powering it with a 3.7V battery. It worked fine for a long time before this behavior started though but it might just be that the battery was partially discharged with a lower voltage than 3.7 and it stopped working after charging (not sure about this). Do you think there could be any other reason? I've seen this behavior on two different ppks.