It was a time when there was no Battery Backup for any internet USB device , then i decided to design a trick to power the USB from the mobile battery , a USB female pin were for USB to be powered , dual color LED were use for indicating charging & on indication , a slide switch use to on/off the USB,a small pin female were used to charge the battery, a very simple project every guy can assembled it, plz care of USB & charger pin polarity, with high apms battery up to 5 to 8 hours backup can be expected ,
It can be easily charge by using common Nokia charger,
don’t worry about over charging there is built in cutoff circuit in side every
mobile battery,
One thing I missed that there should be USB pin
charging facility and schematic of this project, no issue I will add
it soon.
