12 volts mobile charger

Hello eveyone...
My problem is that I converted an ordinary 220V mobile charger to an input of only 12 volts to charge my phone,and it really works but the problem is that it takes a couple of hours to charge. and cant full my cp..I guess, I have something to do with its frequency but how?

I also bought some cigarrette charger they called and tried but also doesnt satisfied me specially when i look the circuit designs inside... I like isolated secondary to be safe,(like an SMPS).,
Sorry for my English......
Dear friends feel free to comment....tnx

The charge time of your phone is determined by the phone itself; not by the 220/12V adapter (unless the adapter has an extremely low output current capability).
By 'cigarette charger' I assume you mean a charger powered from a car's cigarette lighter socket? If so, the supply voltage is only 12V and is safe without the need for isolation.

yes I agree w/ that.charge time depends on your phone.. my phone originally draws only 300 mA at 5V. I have a variable power supply and set it to the given value,my phone then was charging but after almost 5 hours I disconnect to check but why is that still not charge...I am wondering why..? do somebody explain to me this thing...thanks

It most probably needs MORE than 5V to charge.

Measure the voltage the original charger provides.

You need to know the first charger voltage is ?

hahaha! amazing. toink

not a good idea, nobody still dont give me the right ans.