Mp3 player adapter

F

freak89

New Member

• Nov 21, 2008

• #1

Hello every body
i hope you are okay

Now i have an old usb flash-Mp3 player it is consume alot of power so it need more batteries and " she got no money in the bank" i mean i have no money so i get an old nokia charger 5V-890mA and wired it with an old usb cable
only pins 1 with VCC and pin 4 with GND

it starts but soon it say " LOW POWER " and it also can be powered when i plug it in Computer although the usb from computer can derive 5v-200mA as i know

can you tell me where is the ERROR ??

 

blueroomelectronics

Well-Known Member

• Nov 21, 2008

• #2

Is it a rechargeable MP3 player? What model?

 

F

freak89

New Member

• Nov 21, 2008

• #3

it is like those ones

**broken link removed**

 

blueroomelectronics

Well-Known Member

• Nov 21, 2008

• #4

Is it a standard AAA battery inside? Is it rechargable?

 

F

freak89

New Member

• Nov 21, 2008

• #5

Is it a standard AAA battery inside? Is it rechargable?

Click to expand...

Yes AAA battery inside

But when i connect it to computer with no battery it works perfectly

 

E

ezpcb.com

New Member

• Nov 21, 2008

• #6

Hi Freak

I know where's the problem as I had designed many many MP3 circuits. The charging circuit is controled by the micorcontroller inside the MP3. Charging won't be triggered on unless a real USB connection is detected. In some circuit you can start charging by connect a 1.5k resistor betwwen D+ and VCC. In most player you can't start charging unless connect it to a real computer

 

F

freak89

New Member

• Nov 22, 2008

• #7

i never wanna to charge it i want to power it from the usb as i will connect it to nokia charger

 

F

freak89

New Member

• Nov 22, 2008

• #8

any one could help me wiring this

 

blueroomelectronics

Well-Known Member

• Nov 22, 2008

• #9

Google is handy.
How To Make Your Own USB Car Charger For Any iPod Or Other Devices That Charge Via USB

 

J

johnsmith123

Member

• Nov 23, 2008

• #10

Do you have to hook it up to the PC?
why not build a 1.5 Volt regulator using a LM317 use it in place of the battery?

I did this for an mp3 player, and it has been working for more than 2 years!

figure out what you need here:
**broken link removed**

 

Attachments

• 1.5VReg.GIF

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Menticol

Active Member

• Nov 23, 2008

• #11

Or wire directly the (Data -) pin directly to (GND), worked for my Gigatech chinese mp3 player