Need pure sine wave inverter for car charging of iphone/ipad/etc.

Discussion in 'Mac Accessories' started by kudukudu, Apr 3, 2013.

  1. kudukudu, Apr 3, 2013
    Last edited: Apr 3, 2013

    kudukudu macrumors regular

    Oct 24, 2007
    I currently have a cheap Targus power inverter that I use to charge/power my laptop, iphone, ipad, etc. While I have used this inverter for years, I have noticed odd behavior with my touch screen controls on my iphone and ipod when plugged into the inverter which does not give me the warm and fuzzies. I am concerned about damaging future peripherals and would like to invest in a pure sine wave power inverter in the $150 to $200 range.

    Unfortunately it looks like a lot of pure sine wave power inverters have cheap fans which quickly ramp up to full speed. I don't want to have an inverter in my car that sounds like a jet engine at take off. This inverter sounds pretty good, but some of the reviewers on amazon complain about the fan noise:

    Any suggestions?
  2. Giuly macrumors 68040


    A MacBook takes something between 16.5 and 18.5V, iOS devices 5V. Converting the 12V from your car to 120V, then back to lower voltages is probably the most inefficient route you could possibly take.

    But the 85W MacSafe charger with integrated USB port to the rescue.
  3. rgarjr macrumors 603


    Apr 2, 2009
    Southern California
    Yeah I used to run a carpc and used a small power supply to boost car 12V to about 18V.
  4. COrocket macrumors 6502

    Dec 9, 2012
    Like Giuly said, you can just use a car adapter since both the cars battery and your battery on your mobile device are both DC current powered. All it does is transform the 12VDC into 5VDC for ipad/iphone.

    In fact, if you are concerned about the "quality" of the electricity going into your device, the car setup Giuly linked to is probably better than plugging into your house electricity anyways since the power bricks have to both transform and rectify the power from 120VAC into 12VDC.

    If you are having issues with your touchscreen, I'd look at other possible issues first.
  5. kudukudu thread starter macrumors regular

    Oct 24, 2007
    Guily, thanks interesting point. You peaked my interest and I wondered how safe this would be. I found this summary here:

    "Ironically, if you use an AC inverter to power a computer or television, the power supply in the device is converting the 120-volt alternating current into a much lower voltage direct current. The sensitive electronic circuits in these devices need low, regulated voltages to work, so you're actually converting DC to AC so it can be changed back into DC again. You can't use straight direct current without the AC to DC inverter because the device's power supply needs the AC power in order to properly step down and regulate the voltage"

    I am sold on the idea of using a DC only device like the one you have suggested
  6. kudukudu thread starter macrumors regular

    Oct 24, 2007
  7. takeshi74 macrumors 601

    Feb 9, 2011
    What made you think that you needed pure sine wave? Few things really require it these days. Questionable chargers are known to cause issues with capacitive screens and that may actually be your problem.

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