Mobile phone charger from USB help

[ahonda55]

hi all
in the beginning please don't say i am creazy when you read this !!!!
you know the USB of any PC has voltage output.
some pocket pc's could be charged from the usb.
now i want to make a simple connection to charge the mobile phone from the usb, as i can charge my phone using any PC.
i want to know the usb schematic, pins and volts if you have.
and i will try to make it.
but, what about current ?? should i work directly on volts only?
the charger will be for nokia phones, i have 6610 noka.

any help? any suggestions?

i aprecciate your help and thank you very much

 

[indecided]

www.google.com
www.google.com
www.google.com

search terms : USB pinout

site : https://pinouts.ru/data/USB_pinout.shtml

fact : just charge your mobile (likely at 3.7v, 200-500ma) straight from USB 5v and maybe it's lifespan will drop a year at most if you're lucky. Most cheaply designed charging cables don't regulate the voltage - it's just a piece of wire!

You can always integrate a regulator in if you want.

 

[ahonda55]

i have read that the usb pins givs 5v, and my original phone charger output is 6.3v, i think the 5v will work without damage.
should i use a simple regulator, i mean a 7805 for example to make it much safe ?

thanks for reply

 

[Someone Electro]

That reg wont work on the 5V rail just conect directly.

My phone uses this as charging.The charger is aculy a mini USB conector whith the 5V line.Oh and the charger is rated for 5 V

 

[ahonda55]

thanks man

now i may connect my phone to the USB, no problems with the current ?

 

[michel__ba]

hey,i would like to build a small piece using 1 AA battery to charge my k500i mobile ,my adapter indicate 4.9v 450ma
anyone can help me plz? give me schematics for this project
i aprecciate your help and thank you very much

 

[audioguru]

If you use an AA alkaline cell to drive an inverter then its stepped up voltage is rectified to make 4.9V, the 450mA output current requires a whopping 2.3A from the little AA cell! The voltage of a new AA cell will begin at about 0.9V then it will drop very quickly and also the stepped up voltage will drop. The cell will be dead in about 10 minutes. A phone's battery needs to be charged for up to 2 hours.

 

[michel__ba]

10x mr $crooge ok if u can help me plz if i want to make like this mobile charger with a 9v battery how can i make it plz

 

[aibelectronics]

Are you sure buying a new charger isn't a better idea? why waste your time reinventing the wheel?

 

[michel__ba]

there is a component at shops that we can use 1 alkaline cell to chrge mobiles (emergency phone charger) can anyone help me and send to me the schematics?10x

 

[justDIY]

there is a component at shops that we can use 1 alkaline cell to chrge mobiles (emergency phone charger) can anyone help me and send to me the schematics?10x

check out www.maxim.com, under power management - boost converters

they have the chip that will do what you ask, although I don't know about supplying so much current, and I doubt your emergency charger supplies much current either. my guess is 50-100mA

be mindful the chip is TINY, designed to go in cheap MP3 players that run off a single aa or aaa battery. it will not be an easy circuit to bang out on a breadboard.

 

[audioguru]

Using a switched mode power supply with a 9V alkaline battery will provide slightly more charging time than one AA alkaline cell with its voltage stepped up. The 9V battery will be dead in about 13 minutes. Useless.

 

[michel__ba]

transformer

i have a sterio step down transformer ,(220v-110v)at primery.
can i connect 220v to primery and leave secondary unconnected ?
nothing will happen?
10x (reply quickly plzplz

 

[G8RPI]

Hi,
The later Nokia phones have a strange requirement for their charge input. I've a commercial USB charger that worked fine on an earlier phone but doesn't work with a 6310i or later. A newer charger (from Brookstones in the USA) works fine. I've had similar problems with car chargers. It looks like the phone needs to see a slightly higher voltage initally.
To save the risk of fying your phone, I'd just buy a USB charger.

Robert G8RPI.