Why it is important that an ideal op amp has infinite input impedance?

To make sure that the voltage signal drops fully on the op amp, it must have a very high input impedance, so that the voltage drops fully across it. If it had a low input impedance, the voltage may not drop across it and it would not receive the signal. This is why op amps must have high-input impedances.

What happens when impedance is infinite?

Infinite impedance means that in theory, no current will flow through the device. That’s good because that current is just lost energy. MOSFETs only need a voltage potential from the gate to the source in order to toggle, unlike BJTs which require current to toggle.

What is meant by input impedance?

Input impedance is defined as the ratio of the voltage and current at the pair of the input antenna terminals:(2.105)Za=Ra+jXa, where Ra is the resistance at antenna terminals and Xa is the reactance at antenna terminals.

Which of the follwing configuration does the opamp function as a high gain amplifier?

open loop configuration
2. In which configuration does the op-amp function as a high gain amplifier? Explanation: An op-amp functions as a high gain amplifier when connected in open loop configuration. These three are the open loop configuration of an op-amp.

Why ideal op-amp has infinite gain?

Ideal op-amp has infinite voltage gain because Explanation: As the voltage gain is infinite, the voltage between the inverting and non-inverting terminal (i.e. differential input voltage) is essentially zero for finite output voltage.

Why op-amp has infinite gain?

A typical voltage amplifier must have zero impedance at output and infinite impedance at input. Impedance creates a barrier, that op-amp couldn’t draw current from the source. Now for the same reason think about op-amp gain. If the input impedance is Infinite then the gain will be infinite.

What is the importance of input impedance?

The reason for making high input impedance is that “The circuit can be driven by any source” to avoid any loading effect. This ensures maximum current is provided by source. The reason to ensure low output impedance is that “The circuit can drive any load”, even the load impedance is small in magnitude.

What is the input impedance of an ideal operational amplifier?

infinite
The current flow into the input leads is zero, so the input impedance of the op amp is infinite. The output impedance of the ideal op amp is zero. The ideal op amp can drive any load without an output impedance dropping voltage across it.

What is the impedance of a resistor as frequency approaches infinity?

For a capacitor the impedance is infinite at D.C. and approaches zero as the frequency approached infinity, whereas for an inductor the impedance is zero for D.C. and approaches infinity at an infinite frequency. Note: The impedance only gives us a value for the magnitude.

Why is input impedance important?