A Tracking Differentiator Has Noncapacitive Input

The major advantages of this circuit over conventional ones are its noncapacitive input, and its independent gain, offset, and differentiating time constant adjustments.

Since the amplifier in the circuit will set the output, the summing point will track the input and the current through feedback resistor R2 will be the sum of the currents through C1, R3, and R5. Read full article