Re: Case mod feasible

2008-09-23 Thread Minh Ha Duong
Dear Breakable, The "Minty power" links at the bottom of http://wiki.openmoko.org/wiki/Battery demonstrates that building a 2 AAA battery pack USB charger is feasible. As 1.2 * 4 is almost 5, building a 4-pack would probably be simpler. You will probably want to connect a 47.5 kOhms resistor

Re: Case mod feasible?

2008-09-22 Thread Kelvie Wong
On Monday, September 22, 2008 15:39:24 Andy Selby wrote: > AAA batteries are 1.5 volts, so 4x1.5=6volts, if you find a diode that > has a voltage drop of 1 volt you won't need any voltage regulation > circuitry. > Actually, most AAA (and AA) rechargeable batteries are about 1.2 volts when full.

Re: Case mod feasible?

2008-09-22 Thread Andy Selby
> Basically what I want is to add 4 rechargable AAA batteries and plug that > into usb port. > That gives me about 1200ma at 4.8v, which should comply with the USB > specification (5v), AAA batteries are 1.5 volts, so 4x1.5=6volts, if you find a diode that has a voltage drop of 1 volt you won't ne

Case mod feasible?

2008-09-22 Thread Breakable
Hi, I am just thinking to do a casemod for Freerunner. Basically what I want is to add 4 rechargable AAA batteries and plug that into usb port. That gives me about 1200ma at 4.8v, which should comply with the USB specification (5v), would it not? This should avoid the requirement for sophisticated