Wrong conversion for mAh to mWh

Ryan Lortie desrt at desrt.ca
Tue May 2 16:18:25 PDT 2006


mAh * mV = µWh, (1/1000 * 1/1000 = 1/1mil).

This is not a bug since the "normalised" values aren't promised to be in
any unit at all -- they are only guaranteed to be in a consistent unit
across all batteries in the system (remember that we original brought
this in to solve the multiple-batteries-with-different-voltage problem).

Relying on this value to be in mW is a mistake.  With APM, for example,
we will not have _any_ way of correcting this unit to mW.

Cheers.

On Tue, 2006-02-05 at 22:45 +0200, Johannes Berg wrote:
> On Tue, 2006-05-02 at 20:39 +0100, Richard Hughes wrote:
> > when we should be doing:
> > 
> > mWh = mAh * ( mV / 1000)
> 
> Since you're dealing with a computer you should probably do
> 
> mWh = (mAh * mV) / 1000
> 
> instead ;)
> 
> But yes, sounds saner than just mAh * mV to me at least.
> 
> johannes
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