USB to USB flash Drive File Copier

[Byte_Butcher]

That is a difficult one to answer.
The VDIP requires 5 volts. Four re-chargeable "AA" batteries will give ~4.8 volts, close enough but for how long.

Be cautious with your battery types here... 4 NiCad AA's will give about 4.8v, but 4 rechargeable ALKALINE AA's can give over 5.6V +

For linear regulators, these aren't too bad...
http://ww1.microchip.com/downloads/e...Doc/21991c.pdf
Only a couple hundred mV dropout voltage, so they work OK on 5 v circuits from a 6v battery.

You may want to use a switching regulator. Could have one that works with a battery input from 3 to 6 volts, then four "AA" batteries of any type will work. Depending on the circuit the efficiency can be very good.

If you need to run off a wide supply range, including sucking batteries down "to the last drop" then a good switching supply is THE way to go....


steve

[Dave]

Byte_Butcher, Where do you find rechargable ALKALINE AA's ? I have never heard of such a thing.... I'm curious...

Dave Purola,
N8NTA

[Byte_Butcher]

Byte_Butcher, Where do you find rechargable ALKALINE AA's ? I have never heard of such a thing.... I'm curious...

/Cough/ err... well, they do exist, and a quick google search should find you some. But I was MISTAKEN about the ones that I have. I was sure it said Alkaline on the package when I got them, but on closer inspection, these say NiMH on the side of the battery.

So I guess I meant to say that" 4 rechargeable NiMH AA's can give over 5.6V +" Sorry...

steve

[mackrackit]

What is the brand of the NiMH and AH of the batteries you use?
The NiMH I use are 1.2 volts at 2500 AH.

[mackrackit]

OPPSS!
That should be 2500 mAh

[Byte_Butcher]

Duracell, 2650mAh.

They're rated at 1.2V, but terminal voltage on a freshly charged one exceeds 1.4V


steve