On Fri, Apr 15, 2011 at 1:12 PM, Olin Lathrop <olin_piclist@embedinc.com>wr=
ote:

>  It does.  The "gain" of a BJT (more specifically Hfe) is the collector
> current divide by the base current.  If the base current is 1, then the
> collector current is GAIN, and the emitter current is GAIN+1.  In your
> case,
> the collector current is the battery current, but what you measure with a
> low side current sense is the emitter current.  Note that the ratio of GA=
IN
> to GAIN+1 approches 1 as the gain gets large.
>
>
I was thinking of doing high side current sensing like the first diagram
here: http://i.cmpnet.com/planetanalog/2009/02/C0363-Figure1.gif

That's why I didn't understand all the talk about inaccuracies.
--=20
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