charging bl-5c | bl-6c

Michael Shiloh michael at
Fri Feb 15 23:59:04 CET 2008

Andy Green wrote:


>> By the way, it is my understanding that the coulomb counter is indeed a
>> custom add-on for us, meaning that the standard BL-6C and other
>> compatible batteries will in fact not work for us.
> Well, the former may be true but the latter isn't -- the PMU is
> blissfully unaware of the HDQ stuff.  Its like some inbred country
> cousin gas station attendant that will just fill up any car that stops
> by if it has the gas tank cap in the right place.  HDQ happens outside
> of the charging system completely.

Understood. I didn't mean that it is incapable of doing so, just that it 
might be unwise for us to do so, due to our inability of reading the 

>> In GTA01, how did we read the temp sensor? Was the analog to digital
>> converter (ADC) an additional component, or are there any ADCs on the
>> Samsung SoC? If the former, then I presume we don't have that chip on
>> GTA02, which means we can not safely charge a battery without the
>> coulomb counter, because we can't measure the temperature.
> There are ADCs in the CPU, but GTA01 did it using an ADC in the PMU
> itself.  I never understood from the schematic if GTA02 has a thermistor
> hooked up or not, it just shows a normal resistor there.  But AIUI the
> smart battery takes care of overtemp protection privately, additinoally
> we can tell the battery pack temp over HDQ to 0.1 degrees C.

Right. My question is for batteries that do not have the coulomb 
counter. Can we safely charge them not knowing the temperature?

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