Currently, I am using a Samsung Omnia W and mostly I am using my 2013 MacBook Pro's USB port for charging it.

Is it fine for charging the battery in the mobile phone? Sometimes, I have received a 'high power consumption' warning (from USB port) on laptop as warning.

What is the power output of the USB port compared to the mobile's input power for the battery?


Apple computers and displays without USB-C ports will strictly adhere to USB standards for all non-Apple hardware, so you will be limited to 5 V at 500 mA for charging your Samsung phone.

Third party chargers or wall adapters will be needed if your device is requesting or using more than 500 mA since Apple will shut USB ports that exceed the spec and are not Apple to Apple.

Also, this USB over-current condition is safe, expected and like a modern circuit breaker, you unplug the device and reset the circuit except for USB on Mac, the reset happens immediately when you unplug the offending device. Unless your device has a sync only setting, you'll need a special USB cable to sync and have to charge it elsewhere than from your Mac.


This is a superb question and has come across my desk and under my nose many a times.

If you are getting a "High Power Consumption" message then do NOT use that device with that computer. If you don't get the message with your MacBook Pro while plugged into the wall then you should be fine.

I am also going to use this platform to mention something that I see happen again and again. Using a device or cable that is not authorised or gives power consumption warning messages can cause the SMC of the main logic board to go haywire in such a fashion that it will no longer start up or shut down in the middle of use.

The only way to resolve that is a hard SMC reset and that is too much trouble. Avoid it if you can, charge with an AC adapter for your phone for best results.

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    If your machine doesn't continue to operate normally after the overcurrent protection alerts you and shuts down the USB port, there is a hardware failure and potential safety issue. Take that Mac in for service. SMC reset usually is for larger power events and very rare ( once every 8 months to three years - not something to do routinely in response to an expected USB overcurrent situation. ). Simply unplugging the device that draws too much power alone or in conjunction with other devices on the same bus and the safety should reset all functionality immediately. – bmike Dec 30 '13 at 16:21
  • Thanks at bmike for the addition. My system doesn't have an issue though so I think your comment goes better with the OP. Just my thought though. Appreciate ya! – Andrew U. Dec 30 '13 at 16:40

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