I have Raspberry Pi 2 Model B and two USB power adaptors with specs:

Apple charger: 12W 5.2V 2.4A

Samsung (came with galaxy S6): 9V 1.67A or 5V 2.0A

It is stated that my Raspberry would need 1.8A 600mA/1.2A (switchable)

Is it safe to use one of my USB power adapters? Which one would fit best?

  • Do you want to charge your mobiles from RPi? Commented Sep 2, 2015 at 13:46

4 Answers 4


Both power adapters should work as they each can provide at least 1.2 Amps at 5 volts. I would use the Samsung and save the Apple 12 watt adapter for something that requires more than 2 amps (which is 10 watts).


The link you quoted states "Maximum total USB peripheral current draw 600mA/1.2A (switchable)". This is the current the Pi could supply to external peripherals, not what the Pi needs.

In fact the Pi uses less than 1A, depending on what peripherals you have attached. I run all my Pis with an Apple 5W (1A) charger, although I use a powered hub for external HD (which won't work with the Pi and need more current).

If the Samsung claims to supply: 9V 1.67A I wouldn't let it near my Pi (or any 5V USB device). In general is not a good idea to use "chargers" as they often have poorly regulated voltage (which is OK for the purpose), and are designed to charge batteries.


Its good to use minimum 5v/2A power source with RPi2, voltage should not drop below 4.65v, so make sure you use min 5v.Though current is higher it will simply draw your current forward, so no problem with higher current.

Both are good to use with your RPi2.

  • Apple charger: 12W 5.2V 2.4A
  • Samsung (came with galaxy S6): 5V 2.0A

My advice is not to use adapter more than 5v.

  • 1
    Having a voltage slightly above 5V helps mitigate voltage drop from using cheap USB cables.
    – Craig
    Commented Sep 2, 2015 at 15:32
  • Yeah little bit higher is ok, but in questiion hes asking about one more charger 9V 1.67A, i dont want to recommend that. Commented Sep 3, 2015 at 8:31
  • I believe the samsung charger will only provide 9V when connected to a device that supports quick charging, otherwise it acts like a standard 5V USB charger.
    – Craig
    Commented Sep 3, 2015 at 18:27

My RPi 2 consumes 650mA when all 4 cores are fully busy and clocked at 900MHz (so no overclocking) and with my wireless USB dongle powered.

So that's a bit more than 3W fully loaded with one USB device.

You have to think of how many USB devices you will have and if you're going to use any of the GPIO pins. Then you know how much power you need. But I would say that both your power supplies have plenty of margins and should suffice.

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