Solar Cell Charger

Discussion in 'The Projects Forum' started by RodneyB, Sep 30, 2014.

  1. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    A few weeks ago I posted a question about using a 0.3 Watt solar panel to charge a cell phone.

    I am not sure why but this circuit seems to be discharging the cell phone . Not sure why.

    Any help will be appreciated.

    Thanks
     
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  2. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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  3. Kermit2

    AAC Fanatic!

    Feb 5, 2010
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    i dont see anything preventing backward current flow into your solar cell. a series diode seems to be required.
     
  4. wayneh

    Expert

    Sep 9, 2010
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    0.3W is way too small to charge most phones. You need a minimum of 100mA at 5V, which is 0.5W. And I think a minimum of 0.5A is more likely, meaning 2.5W. That's after all losses.

    Many devices won't charge unless they see an adequate supply. Some also look for proper voltages on the data pins. You should be able to research what your particular device requires.
     
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