mmtbb

I tried a test with 1 AA battery. The light on the axim doesn't turn on. So, do I have to have 5 volts to make it start charging?

howdy2k2000

Sorry, I should have clarified for Axim. Yes, the axims internal circuits will not recognize any voltage until it sees about 5 volts. I set my adj. regulator to around 6 volts. You can use 4 alkyline (non rechargeable) batteries for 6 volts (1.5 x 4), but they dont last long and that would get expensive. NiMH (rechargable ) batteries are only 1.2 volts each so 4 wouldn,t cut it.
I'm not on here very much but you can pm me with any question.

mbloof

Originally Posted by mmtbb

HI, 1) I was looking at those single AA battery emergency chargers that are everywhere online. How do these work if the device has a higher voltage? 2) Could this work with a "C" or "D" battery?

Some of these devices may have a "stepup regulator" which will take a 1.2-1.5V battery and step it upto 3.6 or 5v so that it can charge your device.

Check the output voltage of the device before buying.

(DIY devices could easily do the same thing with the right regulator)

__________________
[FONT=Times New Roman][COLOR=Blue] - Mark0 (The Technologist)

howdy2k2000

(DIY devices could easily do the same thing with the right regulator)[/QUOTE]


Adjustable step down switching voltage regulator

howdy2k2000

LVBoost - Boost Converter

howdy2k2000

Still going....

mmtbb

quick question. I have 4 AA 1.2v 2500 mah rechargable batteries in a battery pack.

If I plugged this in to a device, what would the constant current be? For instance, It wouldn't be 2500 mA, right?

Zaniax

Originally Posted by mmtbb

quick question. I have 4 AA 1.2v 2500 mah rechargable batteries in a battery pack. If I plugged this in to a device, what would the constant current be? For instance, It wouldn't be 2500 mA, right?

2500 mAh means
2500 mA for 1 hour or
250 mAh fo 10 hours

Theoretically that is :o

Zaniax ©

mmtbb

If a pocket PC could use only 1000 mA, does this mean that I would burn out a Pocket PC if I made a charger with 4 AA batteries rated at 2500 mAh?

howdy2k2000

Originally Posted by mmtbb

If a pocket PC could use only 1000 mA, does this mean that I would burn out a Pocket PC if I made a charger with 4 AA batteries rated at 2500 mAh?

No, the PPC (or any other electric circuit) will only draw the amount of current (amps) that it requires. Now if you connected too much voltage it could do damage. Just like the battery in your car has at least 250 amps but it does not destroy the radio which runs on less than 5 amps. However if you connected a 24 volt battery to the radio it would destroy it.