A while ago, I bought myself a desktop power supply that displays the Volts and Amps drawn by any of it’s USB ports (Pine 64’s PinePower Desktop). Since then I’ve been using it to charge my fairphone 4, using its 65W USB PD port. Typically, I see it draw ~2A @ ~9V till somewhere between 50% and 65%, when it drops to ~1.5A @ 7V. So far, so reasonable.
Recently though, I’ve seen it shortly spike to the low battery percentage charging setting while above 65%. It behaves as if it renegotiates how much power it’s supposed to get from the USB PD source, draws a bit at those 18W and then drops back to the 10.5W probably intended.
I’m writing this post for two reasons:
- Reporting this bug to see it fixed
- Understanding how much this could potentially harm battery life for users charging via USB PD charging bricks.
Regards
db-b111