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AD8211 AC current monitoring **EDIT using AD8418 instead


**EDIT** I read that my original part AD8211 is a unidirectional current shunt monitor, so now I have revised the question using a bidirectional chip the AD8418.    Question has been re-written with AD8418.

I am confused to whether the AD8418 (current sense amplifier) is good for measuring AC sine wave current.   The AC sine wave is created by the AD9837, a programmable waveform generator.   The resulting sine wave (~400Hz, 100mV pp) is fed into an audio amplifier STA540 (attached photo below --> IN_L) to amplify the sine wave to about 6V pp.   I am using the amplifier in bridge mode as shown below but instead of the OUT_L speaker, I simply have a 4ohm shunt resistor.   The AD8418 inputs would of course be connected to each side of the shunt resistor.   

Since the signal is a true AC (0V centered) sine wave, I was unsure if this is an ok signal for the AD8418 to measure.   Especially since a lot of current sensing applications talk about "high side" and "low side" sensing.  Neither side of the shunt resistor is connected to GND so I'm really not sure if this could be classified as either high or low side.   With AC signals is there such thing as a high or low side?   Any help is appreciated!

AD9837 Datasheet 

STA540 Datasheet

AD8418 Datasheet


Revised wording.
[edited by: nanok at 11:46 PM (GMT 0) on 20 May 2019]