Using Apex Microtechnology’s power op amps for voltage controlled current sources (VCCS’s) application note, Link here (PDF)
Voltage controlled current sources (or VCCS’s) can be useful for applications such as active loads for use in component testing or torque control for motors. Torque control is simplified since torque is a direct function of current in a motor. Current drive in servo loops reduces the phase lag due to motor inductance and simplifies stabilizing of the loop.
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