Messages in this thread | | | Date | Fri, 18 Dec 2009 09:48:50 +0100 | From | Pavel Machek <> | Subject | Re: [POWER] battery calibration parameters from sysfs |
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Hi!1
>>> Yes, but in that case you might as well just purchase a coulomb >>> counter with a built-in accumulator and an I2C/SPI/microwire interface >>> save yourself some PCB space and cost (maybe)
Hardware is already given.
>> Well, Pavel attempts to implement a "poor man's Coulomb counter" or at >> least "poor man's Ampere meter" for devices that are not equipped with >> any of it. > > I think the "poor man's Coulomb counter" is a loser, the errors will > overwhelm you too rapidly. The estimated rate of discharge could >> work,
Actually android phones do "poor man's Coulomb counter", and it seems to mostly work.
> based on what clocks, regulators and so on are running, but I am not > sure how useful that number is really given you can't realistically > integrate it due to the big error it is bound to have. ... > Otherwise for L-ion batteries, looking at the voltage level alone, > filtered to remove GSM transmit slots etc, is really quite workable for > estimating charge status.
Well, you have to compensate for backlight power; and yes, that's what I'm trying to do. Pavel
-- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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