Hello! Could you please clarify the charts for "absolute analog input current" and "differential analog Input current " in the datasheet http://www.analog.com/media/en/technical-documentation/data-sheets/AD7124-4.pdf

I thought that "differential" means **difference** between the input currents of any two analog inputs. So this is simply I(AINx) -I(AINy).. This leads to conclusion, that differential current can not be greater than absolute value of current (any of I(AINx) or I(AINy)). But if will take a closer look at the charts above, we'll see that [for example] differential input current for gain = 64 is more than 5 times greater than absolute value. How this could be ?

Hi,

Correct, the differential input current is the difference between two analog inputs. Figure 41 shows the positive analog input current. If the negative input current has the same magnitude, then the differential current is zero. In practice, the negative input current could be larger or similar in magnitude and same or opposite polarity with positive input. Therefore, the differential current can be higher or lower than the positive or negative analog input current.

Thanks,

Jellenie