USB Mobile charger : samsung

Hey guys! I have a Samsung galaxy S duos (GT-7562). I am traveler , hence I tend to use GPS a lot which drains my mobile battery pretty fast. So I wanted to build a portable charger for my mobile. I got a LM7805 voltage regulator and built a 5 V power supply. I connected it to a female USB port and tried to charge my mobile, but in vain. Then i took a SMPS from a spare computer in my workplace and connected the 5 V output to the female USB port and tried to charge my phone. Yet again my phone did not charge. I was puzzled, my Raspberry Pi was working with both the chargers but not my mobile. So I wondered whether Samsung engineers have utilized the same idea as apple. I have an apple iPod 4G to charge apple products you have to connect thedata pins to a certain potential, this is to prevent fake charging. So after a little research I found that the data pins must be shorted and the pins should be connected to +5 V in series with a 33K resistor and connect it to ground with a 10K resistor in series. As shown in the pic above.

Here are the pics of the USB charger I made...

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