83-op-amp-differentiator-simulation

Inverting differentiator amplifier realized with op-amp is given in figure bellow.

Simulate op-amp inverting differentiator amplifier.

op-amp-differentiator

Op-amp voltage differentiator is the circuit that differentiates input voltage over time. Input impedance is equal to

diff_eq01

and feedback is resistive (resistor R1).

Output voltage can be calculated as function of input voltage by equaling currents. V is on the virtual ground, so input current for smooth periodical signals is:

diff_eq02

The same current flows into resistor R1, so output voltage, is:

diff_eq03

For smooth periodical signals, complex operator jω is equal to voltage over time differential operator

diff_eq04

so output voltage is

diff_eq05

In order to change amount of energy stored in capacitor (decreasing or increasing energy amount alike), some non-zero time has to be consumed. Voltage on capacitor can’t change in time instant. So, if one of the capacitor electrode change it potential suddenly, another electrode changes self potential for the same amount. This feature of capacitor makes it impropriate for differentiating input pulses, since V will be shifted from virtual ground.

Op-amp differentiator amplifier is not so close to ideal differentiator, as voltage integrator is close to ideal integrator. Voltage integrator behaves as integrator for both smooth and pulse inputs.

Go to op-amp inverting differentiator amplifier simulation.
External links:

Op-amp differentiator amplifier on Electronics-Tutorials

Op-amp differentiator amplifier on wisc-online

Posted in tutorials

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