Transforming 4.5V charger to a usb charger

[izua]

Hi! I have a bunch of devices that charge only through USB. I also happen to have around lying an old ericsson charger (i'm not sure if it's an adapter or a charger) rated at 4.5 V 300mA. (it's a type 4020061 BV)

How can i step up from 4.5 V to 5 and make it a supply instead of a charger? is it possible? Would it be difficult? Any ideas appreciated

 

[A.Anand Srinivasan]

Re: 4.5V to usb charger

since it is DC you would need a DC-DC converter step up the voltage to 5V,,,,

 

[ekasitv]

Re: 4.5V to usb charger

Normally, the USB will feed the power supply 5 VDC at pin 1 comparing to pin 4 GND. For the charger, the voltage level 5 VDC and 4.5 VDC should not make any thing difference. I guess you have the problems on the pinout between the 4.5 VDC charger. Although the excellent charger circuit is required the pulse, I believe the constant 4.5 VDC should work. I suggest to check the pinout again.

 

[eanic]

Re: 4.5V to usb charger

Circuit USB port AA NiMH and NiCd Battery Charger by IC 393
**broken link removed**

Source : http://www.stefanv.com/electronics/


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