If i wanted to build a programmable current source, that could provide up to 1 amp of current, what practical level of precision could be achieved without going too mad with specs and design?
Assume i use a 16b DAC to provide the voltage reference to the closed loop current controller, that's a theoretical maximum resolution of just about 15uA, although in reality, i doubt all 16b could be sensible realised?
Then, the control loop would need to amplify the voltage across a sense resistor, which i guess could be a relatively large value ( i don't need a particularly low output impedance, as the current is just being run through a shunt to calibrate that shunt). Obviously, there will be some offset and gain errors here too
Finally, the unit will need to operate at a sensible range of room temperatures, although i can include temperature measurement and hence correction in the firmware
What have people achieved with similar designs?