Bob J wrote:

>> What it your requirement for the current proble? 

> 5mA to 1A or so...

Don't you need a few different sense resistors for such a range? Hm, maybe
not... 1 ohm/1 W may do it. But for the low currents, a higher resistor
would increase the SNR.

Other than a sense resistor (or a few manually or automatically switchable
sense resistors), it's probably "only" a differential amp, possibly
implemented with an isolation amp to get the common mode voltage down.

Gerhard

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