current rate for charging

[rakirajueee08]

I have a source of about 10v and with a resistance load of 0.5 ohm i am getting current of about 200ma.Can I charge a mobile with it? if this current is not enough then please suggest me a way to increase current as i can sacrifice about 4v to get that current because i need 5 v to charge a mobile?

 

[pinout]

look at a switch mode converter for 10V to 5V and at near 90% efficiency you should get around 350mA charge current for your 200mA input.

 

[Genovator]

First, it depends on the mobile battery you want to charge. If it is a common Li-ion battery like BL5C, you can charge in 200mA, but charging will be slow as these batteries generally charge with around 350mA.
Second, 10v is very high for charging for 3.7v batteries. You have to reduce it to 5v. See if you could manage MAX1744. You will be saved from sacrificing 4 or 5 volts. Or try using 7805 and see.

 

[rakirajueee08]

actually i mean by sacrificing of voltage that i want to get more current like you said 350ma is needed by sacrificing the extra voltage as i need 5 v to charge?i know if i connect 7805 it will give 5v? please suggest me a way to increase current?thank u?

First, it depends on the mobile battery you want to charge. If it is a common Li-ion battery like BL5C, you can charge in 200mA, but charging will be slow as these batteries generally charge with around 350mA.
Second, 10v is very high for charging for 3.7v batteries. You have to reduce it to 5v. See if you could manage MAX1744. You will be saved from sacrificing 4 or 5 volts. Or try using 7805 and see.

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can you please please share a circuit diagram for switch mode converter for 10V to 5V?thank you so much.

look at a switch mode converter for 10V to 5V and at near 90% efficiency you should get around 350mA charge current for your 200mA input.

 

[pinout]

I haven't got a circuit, but that is the way to go. Just Google it and there are lots of iCs and circuits.
If you want to do it cheaply (due to mass production) have a look at a car USB converter/ charger.
I'm sure these will work at 10V and the 5V will be good for you battery charging circuit.
Make sure you use a good high quality battery charger circuit with safety features if you are planning to charge a Li-ion battery stand alone, but it's in the phone the suggested car to USB route seems ideal.

 

[Genovator]

Just search for the ic I mentioned, MAX1744. Its a kind of switch mode converter.