Tool/software: TINA-TI or Spice Models
You may find my design. I used 4 parallel op-amp for higher current supply. There is no problem with TINA simulations.
my plan is changing current range with relays. Resistor values may change to compensate current range. I'm also planning to measure applied current to compensate leakages.
Paralleling 4 op-amps will reduce noise or not?
Is this possible to get %1 accuracy?
Any suggestion to improve my design?
How will opa209 output leakage current affect my precision?
Also, I want to use triax connector for current output(R_LOAD). How can I drive inner shield of triax(Guard)?