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Old 03-12-03, 04:14 PM   #6 (permalink)
DennisFranz
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Quote:
Originally posted by shieldwolf
Thanks for the quick replies. Is there any danger with "recharging" over the USB port?

Randy
The only danger I have found is it only recharges at 55% and better. YMMV.

Also when recharging via USB, turn off the Axim. Once it reaches 90%, I would say it is safe to leave it on (or untill the green light shines).

The problem is either voltage or amperage. The Dell power block is:
5.4V 2410 mA
USB is:
5.0V 500mA

There have been many claims of the voltage but I think its an amperage problem.

Normal circuitry will tolerate a 10% above or below voltage and usually more. You see the amperage is almost 5X more with the Dell power block.

I think that once the charging circuitry and the battery falls below a threshold or power (voltage x amperage) that the USB line keeps the circuit open and the battery actually begins to drain. I have seen it and if you get a USB charging cable, you will too if you try it.

Try this link for a charging circuit. I don't mean that it is a direct application of the charging BUT it does state the USB specifications as far as voltage and amperage.
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