Archives For USB Charger


I know there are plenty of USB chargers out there for you to build. But here’s one that doesn’t use a voltage regulator or an IC chip to power it. The basic concept is to use 4 – AAA rechargeable batteries (1.2V a piece) to power the USB and a couple of solar cells to charge the batteries. If you’ve done the basic math you’re probably wondering how 4.8V (4 x 1.2) is going to power a USB device which requires 5VDC. Well that’s actually how I came up with the idea. Continue Reading…

Now you can charge your Mobile Phone from the USB outlet of PC
This simple circuit can give regulated 4.7 volts for charging a mobile phone. USB outlet can give 5 volts DC at 100mA current which is sufficient for the slow charging of mobile phones. Most of the Mobile Phone batteries are rated 3.6 volts at 1000 to 1300 mAh. These battery packs have 3 NiMh or Lithium cells having 1.2 volt rating. Usually the battery pack requires 4.5 volts at 300-500 mA current for fast charging.
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