Integrator and Derivative
Integrator
Lets say I have a input voltage
, where I want that
, the out put should be such that ,
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Means that the output is the integral of in put .
If we observe the following circuit, which have a capacitor connected to it
The output voltage is something like this
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Similarly we can have one more case, where a resistor Can be introduced along with capacitor .
Now in put voltage = Vi
Out Put voltage is Vo
Voltage across Resistors is
Vr= IxR
Where I values is

Plugging in the value of I in equation, the voltage across resistor will become

We know that a voltage in any given circuit is voltage supplied , which at all instant is equal voltage absorbed by the elements. For the above circuit we can say that
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We know that power dissipated by a Resistor
is very large as compared to capacitor , which have a out put of
. For just for the sake of easy calculation , we can make the assumption that
So we can ignore
Which gives us a new equation
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Now finding ![]()
Creating a Integrator Circuit using Op Amp
For creating a op amp , we need a current derived from
, and than current should pass from a capacitor , which should be somehow connected through a Op – Amp
So lets say we have a following configuration
,The current passing through the resistor will be equal to
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Now as we need to make integrator, so we will be needing a capacitor . So a capacitor is connected in following configuration if a integrator purpose , as the current
is in series with capacitor , so the same current will pass through it .
Answer
We know that current cannot go inside amplifier due to high resistance, so all current will pass through conductor.
Now putting values . For finding vo we apply KCl , which will give us
Differentiator
A differentiator is a circuit that can differentiate, the input signal .
, We know that capacitor have following function

Building Blocks For Differentiator
Lets se we have the following Setup , a where a resistor is connected to a inverting terminal in following configuration .
The value of vo for this will be
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Now for the same , configuration lets connect a capacitor in it
We know that the V across resistor is V=I R ., If we can find the value of I , we can simply find the out put , which is equal to
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We know that current across a capacitor is

Putting value of i, in equation
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