What is an Operational Amplifier (Op-Amp)?
B
A high-gain direct-coupled amplifier with two inputs and one output
C
A transistor with feedback
Analysis & Theory
An **Op-Amp** is a **high-gain voltage amplifier** with differential inputs (inverting and non-inverting) and a single output.
What is the ideal input impedance of an op-amp?
Analysis & Theory
An **ideal Op-Amp** has **infinite input impedance**, so it draws no current from the input source.
In an ideal op-amp, the output impedance should be:
C
Equal to input impedance
Analysis & Theory
**Ideal Op-Amps** have **zero output impedance**, allowing full output voltage across any load.
Which configuration provides **voltage gain with phase inversion**?
A
Non-inverting amplifier
Analysis & Theory
**Inverting amplifiers** produce output that is **180° out of phase** with the input.
What is the voltage gain of a non-inverting amplifier?
Analysis & Theory
**Non-inverting amplifier gain** = 1 + (Rf / Rin), where Rf is the feedback resistor.
Which of the following is a typical application of Op-Amps?
C
Signal amplification, integration, differentiation
Analysis & Theory
**Op-Amps** are used for **signal amplification**, **mathematical operations**, and **analog processing**.
What does CMRR (Common Mode Rejection Ratio) indicate in Op-Amps?
C
Ability to reject common-mode signals
Analysis & Theory
**CMRR** shows how well an op-amp **rejects signals common to both inputs** and amplifies the difference.
Which condition ensures that an Op-Amp operates in the linear region?
A
Open-loop configuration
C
Negative feedback is applied
D
Positive feedback is applied
Analysis & Theory
**Negative feedback** is necessary to keep an op-amp working in the **linear region**.