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Usb charger

  1. Jun 4, 2013 #1
    So I want to make a solar usb charger but am having some problems that i do not understand.
    I know that usb is 5v at 1 amp-ish and so I took 4 rechargable AAs and was getting just over 5v.
    I want to have the solar pannel charge the batteries when there is nothing being pluged into the usb output and the batteries to mainly charge the phone or what ever is plugged into it. or when there is no real light to give 5v.

    so I put the 5v power from my AAs on a usb female end, then plugged my phone into it and nothing really happened, my phone said chargeing but didn't go up in percent at all. I was reading about 40ma btw. anyone know whats wrong?
  2. jcsd
  3. Jun 5, 2013 #2
  4. Jun 5, 2013 #3
    I put 9v of AAs on a 5 volt regulator and my phone was charging but at like 1% increase every 20minutes. there was about 20ma running from the regulator output to the phone, how can I increase the amps, or can I?
    I have a wall charger that puts out 5v at 2 amp, how can it do that when it is experiencing the same resistance as my regulator?
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