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Subject: Re: Hardware charging mod
From: roland (
Date: 2003-09-18

i would like that mod - but keep in mind that (maybe) the ac-adaptor
of archos jukebox isn`t powerful enough to run the archos without the batterie`s
the peak current maybe higher than the adaptor can supply, IMHO.
the batteries are sort of a "buffer" for delivering peak current.
at least, one would need a more powerful ac-adaptor or an extra-"buffer" between that adaptor
and the archos (large capacitor like a "goldcap" or similar?)


----- Original Message -----
From: "Nuno Romao" <>
To: "Rockbox" <>
Sent: Tuesday, September 16, 2003 5:18 PM
Subject: Hardware charging mod

> Hi, all. I'm thinking about making a HW mod to my JBR to stop the batteries
> from being used while it's connected to the charger. I want to do this
> because it seems that the way the charging works right now, the JBR runs off
> of the batteries any time it is turned on, except when it's charging. This
> means that if you leave the charger connected most of the time, the
> batteries are constantly being discharged and re-charged. This seems
> wasteful to me: when something is connected to AC power you expect it not to
> use the batteries except to charge them. So here is what I want to do: I
> would insert a very low value resistor in series with the negative battery
> terminal. I would then add a circuit that monitors the voltage across this
> current sense resistor and activates the charger in such a way that it
> reduces the battery current to zero. This would not interfere with the
> normal charging method because this mod would not affect the charging
> circuit when the batteries are being charged. I looked for a way to do this
> in firmware, but I couldn't see away to do it without sensing the battery
> current. Does anyone have any comments or ideas?
> Nuno

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