This circuit computes the derivative of the input voltage, that is, the output voltage is proportional to the (negative) rate of change of the input voltage. The voltage across the capacitor is proportional to the charge stored in it (the integral of the current). The op-amp tries to keep its - input at the same voltage as the + input (which is at ground), so the voltage drop across the capacitor must always equal the input voltage. This requires the op-amp to have a negative voltage when the input voltage rises (to discharge the capacitor to compensate), and a positive voltage when the input voltage falls. If the input voltage changes too quickly, the op-amp will reach its upper or lower limit, and so it will not be able to hold the - input at ground continuously.
This page is a utility for simulating дифференциатор (инвертирующий) на операционном усилителе online with specified initial values.
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