iPhone 5 Charging too fast, excessive heat in M.B.
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iPhone 5 Charging too fast, excessive heat in M.B.

by Jivix on Fri Jan 25, 2013 8:14 pm

I'm using Mintyboost v3, and my iPhone 5 is charging so fast that it is making the inductor start squealing after a minute of charging (I tried hot gluing around it but it only muffled the noise a little), and the chip is getting hot almost as fast as a shorted out wire.

In addition to that, I tried charging it for about 10 minutes and my Eneloop batteries got so hot that I had to immediately unplug my phone. The batteries were too hot to touch, and my phone's battery had gone from 28% to 40% in only 10 minutes.

Is there any way I can limit the current output of the chip? I put some hot glue on the chip to try and pull heat away from it, but its melting the glue off as I type this. I could try thermal paste & a heatsink next, but I only have so much space available in the tin.
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Re: iPhone 5 Charging too fast, excessive heat in M.B.

by Jivix on Fri Jan 25, 2013 8:55 pm

Update:

If I charge it in short bursts of ~5 minutes, the coil noise goes away after the 2nd interval. If I just let it run continuously the batteries end up overheating and the phone will not charge any more. Once I let the batteries cool down it will charge once again just fine (switching batteries also works out, so you could charge more continuously with two sets of batteries).

Would expanding the number of batteries I am using help with my issues?
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Re: iPhone 5 Charging too fast, excessive heat in M.B.

by adafruit_support_bill on Sat Jan 26, 2013 7:26 am

They do get hot in normal use, but it sounds like your phone is trying to pull much more than 500mA. Did you short D+ and D-? The iPhone 5 appears to follow the new charging standard.
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