Differential Amplifier Question & Answers September 13, 2022 By WatElectronics This article lists 50 Differential Amplifier MCQs for engineering students. All the Differential Amplifier Questions & Answers given below include a hint and a link wherever possible to the relevant topic. This is helpful for users who are preparing for their exams, or interviews, or professionals who would like to brush up on the fundamentals of the Differential Amplifier. Differential amplifiers are the basic essential blocks of operational amplifiers. It is the most powerful circuit present at the front end of various comparators, Audio amplifiers, or op-amps. The purpose of this amplifier is to amplify the difference of both the signals applied at input terminals. Integrated circuits present in analog systems are built by using differential amplifiers. A circuit that produces output Voltage that is in proportion to the voltage differences amid both the signals applied at the input is referred to as a Differential Amplifier. This amplifier behaviour resembles a subtractor i.e., basically signals applied at the input are subtracted. These differential amplifiers are constructed using FETs and BJTs. Three terminals are present in this amplifier among those three, two of the terminals are used as input i.e., Inverting and Non-inverting. Differential amplifier circuits are simple in terms of amplifying the signals as well as the noise present in the signals is rejected. Two outputs and two inputs are in this amplifier. It has improved the Common Mode Rejection ratio (CMRR). 1). Differential amplifier amplifies __________ between both voltages applied at input? Difference Sum Multiplied Added Hint 2). The current at collector is equal in ____________? Inverting Amplifier Non-inverting Amplifier Integrator Differential Amplifier Hint Read More About Differential Amplifier 3). ___________ is a Voltage Subtractor circuit? Inverting Amplifier Non-inverting Amplifier Integrator Differential Amplifier Hint 4). Differential amplifier produces the voltage at output is in proportion to __________? Current Difference Voltage Difference Temperature Difference Volume Difference Hint 5). What are the terminals of a Differential amplifier? Inverting Non-inverting a & b Non-linear Hint 6). What is the output of the Differential amplifier in Ideal conditions? Vo = Ad (Vin+- Vin-) Vo = Ad (Vin+- Vin-)/2 Vo = Ad (Vin+) Vo = Ad (Vin-) Hint 7). Common-mode Gain should be __________ in Differential amplifier? High Low Increased Moderate Hint 8). The ratio of differential and common-mode gains is known as __________? Differential Ratio Common Mode Rejection Ratio Distinct Mode Rejection Ratio Multiple Gain Rejection Ratio Hint 9). What determines the amplifier’s ability to cancel voltages common in both situations of inputs? Differential Ratio Common Mode Rejection Ratio Distinct Mode Rejection Ratio Multiple Gain Rejection Ratio Hint 10). What will be the common-mode gain for a perfect symmetric Differential amplifier? Low High Zero Infinite Hint 11). What will be the CMRR of a perfect symmetric Differential amplifier? Low High Zero Infinite Hint 12). What is the formula to calculate CMRR? 10 log10(Ad/Ac)2 10 log10(Ad/Ac) 10 log10(Ad) 10 log10(1/Ac) Hint 13). Biasing points of the Long-tail resistor network are determined using _____? Kirchoff’s Law Ohms Law Boyles Law Faradays Law Hint 14). How many transistors are used in the Common Emitter configuration of the Differential amplifier? Two Three Four Five Hint 15). What are the various modes of Differential amplifiers? Common or Differential Mode Single Ended Double Ended All Mentioned Above Hint Differential Amplifier MCQs for Quiz 16). Differential amplifier is the combination of __________? Inverting Non-inverting Integrator a & b Hint 17). What is created if flow of signals has a similar direction? Common Mode Interference Differential Mode Interference Coherent Interference Non-Coherent Interference Hint 18). What is created if flow of signals has distinct directions? Common Mode Interference Differential Mode Interference Coherent Interference Non-Coherent Interference Hint 19). How noise is removed from the Differential amplifier? By Rejecting Common Mode Voltages By Accepting Common Mode Voltages By Rejecting Differential Mode Voltages By Accepting Differential Mode Voltages Hint 20). Differential amplifiers are _________ by nature? Linear Non-Linear Static Dynamic Hint 21). While operating differential amplifier, it rejects ________signals? Common Mode Differential Mode Dual Mode Multiple Modes Hint 22). What is the output if there are no differences in the input in differential amplifiers? Zero Infinite Low High Hint 23). A Differential amplifier consists of _______? Transistors Resistors Capacitors a & b Hint 24). In what mode the input is applied at one terminal? Common or Differential Mode Single Ended Double Ended All Mentioned Above Hint 25). In what mode two inputs are applied at the amplifier terminals? Common or Differential Mode Single Ended Double Ended All Mentioned Above Hint Differential Amplifier MCQs for Exams 26). In a differential amplifier _________ are amplified highly? Same Signals Opposite Signals One Signal Multiple Signals Hint 27). What is the configuration used in differential amplifiers? Common Collector Common Base Common Emitter Common Drain Hint 28). The outcome in differential amplifier collected across two collector terminals is known as __________? Balanced Output Double Ended Output a & b Multi Ended Output Hint 29). The outcome in differential amplifier collected across one collector terminal is known as __________? Unbalanced Output Single Ended Output a & b Multi Ended Output Hint 30). In a differential amplifier, if the input is applied at both the terminals is referred to as _______? Dual Input Single Input Single-Ended Input b& c Hint 31). If the input in the differential amplifier is applied at one terminal and the other is grounded is known as ___________? Dual Input Single Input Single-Ended Input b& c Hint 32). What are the various configurations of differential amplifiers? Balanced Output with Dual Inputs Unbalanced Output with Dual Inputs Balanced Output with Single Input All Mentioned Above Hint 33). What is the basic configuration of the differential amplifier? Balanced Output with Dual Inputs Unbalanced Output with Dual Inputs Balanced Output with Single Input All Mentioned Above Hint 34). What is the output equation of a Differential amplifier? Vo = V2 – V1 Vo= V2 Vo = V1 Vo= V1 R1 Hint 35). What is the output of the differential amplifier if V1 is 30 milli volts and V2 is 40 milli volts with Ad is 80? 0 V 0.5 V 0.8 V 1 V Hint Differential Amplifier MCQs for Interviews 36). By increasing the resistance value of the emitter in a differential, what happens to common mode gain? Decreased Increased Vary Doesn’t Vary Hint 37). What are the drawbacks of differential amplifiers? Complexity Needs Proper Biasing a & b None Hint 38). Automatic gain control circuit uses __________? Inverting Amplifier Non-inverting Amplifier Integrator Differential Amplifier Hint 39). What are the various applications of Differential amplifiers? Amplifies Balanced Differential Signal Used in High Pass Filter Circuit Control Systems All Mentioned Above Hint 40). Which amplifier can be used in a Negative Feedback circuit? Inverting Amplifier Non-inverting Amplifier Integrator Differential Amplifier Hint 41). _________ modulation purpose differential amplifiers are utilized? Amplitude Pulse Frequency Phase Hint 42). Why differential amplifier is used in Audio amplifiers? Accurate Control of Volume Noiseless Volume Control a & b Increase in Unwanted Signals Hint 43). What is reduced by using differential amplifiers? External Interference Rejection Mode Unwanted Signals a & c Hint 44). Which amplifier is used for noise suppression? Inverting Amplifier Non-inverting Amplifier Integrator Differential Amplifier Hint 45). Input stage of Emitter coupled logic gates is ___________? Inverting Amplifier Non-inverting Amplifier Integrator Differential Amplifier Hint 46). A Long-tailed pair is utilized as _______? Inverting Amplifier Non-inverting Amplifier Integrator Analog Multiplier Hint 47). Long-tailed pair of arrangement in discrete electronic systems is to implement _________ amplifier? Inverting Amplifier Non-inverting Amplifier Integrator Differential Amplifier Hint 48). Differential amplifiers are used in ________? Signal Multiplexing Signal Demultiplexing Signal Amplification Signal Degradation Hint 49). Servos or Motors are controlled using ________? Inverting Amplifier Non-inverting Amplifier Integrator Differential Amplifier Hint 50). Which amplifiers are preferred in the circuit made of Series Negative Feedback? Inverting Amplifier Non-inverting Amplifier Integrator Differential Amplifier Hint For More MCQs Class D Amplifier Question & Answers Power Amplifier Question & Answers Low Noise Amplifier Question & Answers Cascode Amplifier Question & Answers Positive Feedback Amplifier Question & Answers BJT Amplifier Question & Answers Multi Stage Transistor Amplifier Question & Answers Operational Amplifier Question & Answers Amplifier with Negative Feedback Question & Answers Please fill in the comment box below. Time's up