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Rectifier Problems!? Answered

I got a problem in my rectifier it is not able to charge my cell phone but it's giving out 4.5 volts of current i measured it with my  multimeter  and my cell phone also needs and input voltage of 4.5 volts.  I think my rectifier ( it's circuit is in the given in the image! )  is not good and need to be modified so i can charge my cell phone. Can anybody give me the circuit with a output voltage of 4.5 volts and it's so rectified that it can charge my cell phone .



5 years ago

First of all have you measured the output of the circuit ot make sure it's putting out the required voltage? Secondly what phone do you have? Most cell phones with very few exceptions take 5V to charge there batteries.

Why do you have an inductor in there? Below is a simple power supply great for charging most anything that uses a USB cable or 5V for charging. So devices can't use strait 5V since they want to see a voltage on the USB data lines to verify the device is connected to a suitable source. You can find out more about that in my Universal USB Power Supply Kit instructable. I need to do an update on that and add a rectifier to it so it doesn't matter is you reverse polarities from your power source.

5V converter.bmp

Answer 5 years ago

Another note: What rectifier are you using and whats the voltage drop on it. Many cheap rectifiers can have up to a 1V voltage drop. So if you put 5V in you'll only get 4V out so the output from your regulator will be pretty much 0V. Some nicer rectifiers only have a .5V drop so you wouldn't need the regulator at all.

So if your phone does need 5V you'll have to find a larger AC source voltage that won't exceed the abilities of the rectifier. Or go with a larger DC source and get rid of the rectifier.


5 years ago

You can't HAVE "volts of current".....

Your LM317 isn't wired correctly. Go and take a look for another schematic. You should have TWO resistors with it, one, a 220 Ohm from Out to Adj, the other, a 1.4K resistor from ADJ to ground.

What is carbon core INDUCTOR ? I've never seen one, nor do I see why you have connected one where you have. C1 needs to be a nice 1000uF or bigger.

I am also not sure why your phone needs only 4.5 V, nearly all the ones I've seen need 5V.