Isolation amplifiers with "auto-zero" nulling

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Greetings all!

This is more of a controls circuits question, but it could have audio applications.

--> We are using isolation amplifiers for measuring BLDC motor phase currents. Examples of isolation amplifiers that we have used include the AMC1100 (Texas Instruments), ISO124 (Texas Instruments), and AD210 (Analog Devices).

Most of the isolation amplifiers have offset voltage ratings into the millivolts, which is pretty large (5mV is considered "good").

--> Similar to the auto-zero/chopper-stabilized opamps, is there a technique that can be used to auto-zero an isolation amplifier's output? Perhaps, an auto-zero switching phase that "translates" over the isolation barrier?
 
I have come across a board with an opto one on it. It has a bit more potential as it goes up to 70Khz Yes I have got a data sheet for it ready for when I find a use for it.
 

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