Ever needed your mobile to catch a pic or share something on Facebook, just then your battery runs out. At this moment all you need is an external battery charger. Recently I was checking out of the ones on eBay (see pic) for portable or external mobile chargers and just realized I could make that, and started to build one. At the end I realized it wast so hard and it cost me around 10$ while the orginals were around 30$. And also looks quite like the one on ebay as in the pic.
In this tutorial Im going to show you how to build a simple portable mobile charger. This has a USB output so you can you can plug in various types of mobile phones. So you can stop searching for a charger and start sharing. More ever this is portable and can fit in ur pocket easily . This charger gives a constant output of 5v at 1amp.
Step 1: Parts
2)USB input pin
3)Rechargeable 9V battery
4)A case to get all of this in.
6)Power input pin (see the pic)
Step 2: Circuit
The circuit is quite simple and takes a matter of minutes to build. The circuit is just a voltage regulator, it is a 5v regulator which gives 5v output from the rechargeable 9v battery. I inserted a switch to keep the circuit off when not in use and get a longer charging life.
Insert the switch in between the input DC positive. The other pin of the switch goes to the charger .
This gives us three modes of operation one internal battery charging , off and then an USB charger.
Step 3: Battery
For the battery I used old rechargeable mobile phone batteries which are rechargeable. I used two batteries connect in series which gave me 9V output. You can go with easy ways by using 9V rechargeable battery which comes with a charger. And for the case you could go with an altoids container . To save space You could remove the capacitor , but if your mobile keeps on beeping then add it.