Part Number: OPA192
Other Parts Discussed in Thread: INA180
Hi Guys:
Sorry for reply so late because of the chinese holiday. We also did some test based on our opa192 issue. You can refer the and click "Original question" at the top post.
As you mentioned before, the Rf and Rs tolerance will lead to the accuracy and harmonics. So to minimize the tolerance we also did test by using INAx serise device here. But we found the INAx device will also have the same problem. You can see:
OPA192, CH3: output current; CH4: OPA192 output;
INA180A4 CH1: INA180 output，CH4: output current:
besides that, the gain of INA180A4 is fixed. We can not adjust the feedback loop resistor, so the INA180 will have Steady-state error. The output voltage curve will have a little bit tolerance to the ideal value. But if we use opa192, we can adjust the Rf or Rs at the feedback loop to make the real curve meet the requirement of the ideal value.
But we use opa192, it still have the unstable issue at high speed transient condition. Seem like a blind alley. So do you have some better optimized suggestions to make it stable. Or some other device will be better at this application?
Thanks
-Pengfei
