I used a plug with USB output than may have been inappropriate (output DC5V +/- 0.20V DC500mA +/-30mA). While it was plugged in, the touchscreen stopped working properly (touching one part of the screen would trigger another), I guess because the voltage was wrong? Is there any danger that I did some permanent damage to the phone or the battery? It wasn't plugged in for long.

  • I'm not really sure what you want us to tell you. If the problem went away after you unplugged and rebooted, then it's all good. If it didn't, then your phone is broken. We can't tell which of these is true because you're the only one with the phone.
    – Dan Hulme
    Commented Aug 6, 2014 at 8:49
  • No permanently damage I'd say. Sounds exactly the same like a case I had using a HTC charger on a Motorola device. It's not the voltage causing that, but most likely a slightly different use of the additional "X PIN", see: Why does my phone have erroneous input when connected to a non-OEM power source?
    – Izzy
    Commented Aug 6, 2014 at 10:11

1 Answer 1


You can be 99.9% sure the touchscreen is fine. Battery wasn't damaged too. If the touchscreen still behaves erroneously after unplugging, then rubbing it with a soft cloth should help.

This is a common issue with cheap chargers. It indicates that charger may not be safe to use with any device - it may catch fire or explode. Prolonged use of such chargers can degrade battery performance faster than charging with a high-quality charger.

It wasn't a voltage problem - all USB chargers have the same voltage and you can use any charger with a plug that fits. Charging speed may differ, though - high-end smartphone and tablet chargers are faster than regular mobile phone ones.

  • Charging speed doesn't affect the phone, since the phone regulates the amount of amps it can take, not the charger. So if the charger can supply 2A and the phone needs 0.5A, it only takes the 0.5A. Also, if the charger can supply only 0.5A and the device (tablets usually) requires >1A, it simply refuses to charge. The power quality and consistency, however, is very important, and is the problem with cheap chargers as you mentioned. Commented Aug 7, 2014 at 9:20
  • @onik From my experience phones will charge from low amperage chargers at the rate charger provides, so maybe it depends on chargers and/or phone models. Also, if USB data pins aren't shorted phone will never draw more than 0.5A because it could be a USB host, not a charger.
    – gronostaj
    Commented Aug 7, 2014 at 9:55

Not the answer you're looking for? Browse other questions tagged .