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my extern. DC-DC went bad (but R-Pi still OK!)

Wed May 08, 2019 12:08 am

I just want to congratulate the R-Pi hardware designers for making a solid power supply circuit. I noticed a R-Pi 3 Model B v1.2 I had on my desk was quite warm when I accidentally touched the L1, L2 inductors near the power input. Then I measured the +5V GPIO and saw it was +7.1 V! :o

I was powering this Pi from an external 12V -> 5V converter which connected to the +5V GPIO pin, instead of the normal USB power connector. In turn it got 12V from a regulated supply (which was at +12.2 V) but this piece of ... converter (from ebay) had originally measured at +5.1 Vout, but was now +7.1 V under load, and +9..+10 (varying) open circuit! Shame on me for buying parts from ebay, but anyway just wanted to thank the RPi team for not giving up even with this crazy power input. Thanks!
DCDC-gone-bad.jpg (91.2 KiB) Viewed 120 times

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