I'm a little bit confused about input impedances of AD8210.
I guess the differential input impedance of op amp tend to be large like 100Mohm.
And it's usually defined as Zdif between Vin+ and Vin-.
But when I check the spec of AD8210, it's only 2kohm.
According to the fig1, block diagram, it looks like the differential input impedance is 2kohm as an internal input resistors.
I thought it's a common impedance...
Please give me some advice.