Two differentiators PUBLIC

Two methods of building differentiators from available "perfect" CL elements: capacitor or inductor. Both methods are voltage-in / voltage-out.

These two circuits make use of the voltage/current duality in the theory of electronic circuits.

For example, a constant current applied to a "perfect" capacitor will produce a voltage that changes at constant rate. On the other hand, a constant voltage applied to a "perfect" inductor will produce a current that changes at a constant rate.

Some extra circuit elements are needed to convert both the above into uniform, and interchangeable, voltage-in / voltage-out arrangements.

Scaling These circuits are normalised to 1volt, representing 1 unit, where a "unit" is anything that changes wrt time:-

1V/S input (= 1 unit /Second) gives an output of 1V (= 1 unit)

Testing

1] I have tried all four of the voltage generator (V1) wave-shapes. Watch out for kV output spikes when the input has step edges!

Spike size = input voltage step / time step. So, 2kV for 1V amplitude (2V p-p) square-wave and 1mS simulation time step.

2] I tried to drive the "L" cct from the output of the "C" cct, but the "L" cct didn't work in that configuration...