V G wrote:
> But I don't understand why the high side sensing is difficult.

Because ultimately you want a voltage signal proportional to current, and
that voltage signal will be ground-referenced.  A low side current sense
gets you that directly since one side is ground.  A high side sense resisto=
r
is completely floating.  You therefore have to do a true differential
measurement accross it, which is takes more circuitry and includes various
soureces of error.


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