Solar charger help

Discussion in 'The Projects Forum' started by Penged, Feb 18, 2011.

  1. Penged

    Thread Starter New Member

    Feb 21, 2010
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    OK so I "built" a solar charger for my son's DS using this panel, http://www.harborfreight.com/solar-panel-recharger-41427.html

    and buying a USB to DS cord. I built an adapter to go from the power plug to a female USB being careful to get the polarity correct. When I put it in the sun on the 6V 100 ma the orange charge light on the DS fades in and out. So I blocked about half the panel with a piece of paper and it glows steady. The voltage reading coming off the panel with the paper blocking it is 3.2V. The only thing I can think of is the DS is getting too much power and the overcharge protection is making it pulse on and off. And suggestions on how to fix it so I don;t have to block the panel every time?
     
  2. wayneh

    Expert

    Sep 9, 2010
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    You need to first read the DS info to determine what it "wants". If that turns out to be 3v or whatever, you'll want a voltage regulator to limit it to that.

    Do you have a blocking diode, so that current will not flow backwards in the dark? That alone would drop voltage a little bit (~0.7v). Sometimes you can just add 2 or 3 to drop the voltage enough to squeeze by.

    Why not just use the switch on the panel to supply 3v?
     
  3. blueroomelectronics

    AAC Fanatic!

    Jul 22, 2007
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    Your DS needs 5.2V @ 320mA. That weedy solar panel can't put out that much nor does it appear to be regulated.
     
  4. Penged

    Thread Starter New Member

    Feb 21, 2010
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    The output on the AC adapter is 5.2V and 450 mA and I believe that the solar panel has a blocking diode built into it but my son will grab the DS to play with when he gets home from school so it won't be plugged in after dark anyhow. As far as the 3v option the light won't come on at all.
    I just checked the charger and when the light is fading in and out(I removed the paper), the voltage varies from around 5 to 3.2.
     
  5. Penged

    Thread Starter New Member

    Feb 21, 2010
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    Bill,

    Thanks for the quick reply, I guess my question is why is the light on the DS pulsing at a higher voltage that 3.2?
     
  6. blueroomelectronics

    AAC Fanatic!

    Jul 22, 2007
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    Solar panels never put out their rated (ideal) power.
     
  7. wayneh

    Expert

    Sep 9, 2010
    12,103
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    The DS is looking for its charger and isn't happy - somehow - with what it's finding. It may try to negotiate a charging rate over USB, and of course your gizmo doesn't do that - even though the power may be OK. You MIGHT be able to charge the battery outside of the DS. But be careful to not ruin it.
     
  8. Penged

    Thread Starter New Member

    Feb 21, 2010
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