Battery discharging while plugged in

Mike Montour mail at
Fri Sep 5 17:37:35 CEST 2008

Dale Maggee wrote:
> Hi,
> currently when I have my freerunner plugged into USB, it will charge to 
> 100% and then start (slowly) discharging. If I unplug the USB cable and 
> plug it back in, it charges back up to 100 percent, then starts 
> discharging again.

That might be normal - the charger in the PCF50633 shuts off the charge 
current once the battery is full, and turns it on again when the voltage 
falls below a threshold. It seems that it can discharge quite a bit 
before charging switches back on - in one test my battery got down to 
around 75% before it started to charge again.

The GSM modem draws current directly from the battery so this will cause 
the battery to discharge when the charger is off, even when the rest of 
the phone is powered by USB.

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