Hi team,
My name is Ihsan. I want to ask about the AD8421 output that always varies when I try to calibrate it. The schematic is shown below:
I use shunt resistors 0.1 Ohm and Rg 100 Ohm so I can measure the current in the range of ±500 mA. One side of the shunt resistor will be connected to our constant current source and the other side will be connected to the output of the device. There are up to 40 measurement channels in the same PCB.
I try to calibrate the measurement by connecting the node (To_load) to the multimeter (Keithley DMM7510) and resistor (20 Ohm). After taking the data and calibrating my device, I got an accurate measurement of the current for a 20 Ohm Load, but when I varied the load to 10 Ohm and also 25 Ohm, the error was above 1%. What I want to ask is, is it normal to get this behavior? If not, what would be the case that causes this? Thank you.
Best Regards,
Ihsan
