Pulse Width Modulation Question & Answers September 10, 2022 By WatElectronics This article lists 50 Pulse Width Modulation MCQs for engineering students. All the Pulse Width Modulation 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 Pulse Width Modulation. Electronic devices consist of many modern units of microcontrollers integrated along PWM Controllers because it controls the analog signal generated from the digital device. The generated pulses resemble a square wave. At any instant, the generated wave can be either low or high in time. In Power electronics to have control over semiconductor-made devices, PWM is proven to be effective. Inertial loads like motors can run effectively by making use of the PWM methodology. Because of PWM power losses incurred in the Switching device are considered to be low. Reduction of Average power employing delivered Electrical signal obtained by chopping the signal in the form of discrete partitions is known as Pulse Duration Modulation or Pulse Width Modulation. Maximum PowerPoint Tracking (MPPT) can be achieved using PWM. Energy in the PWM signal is distributed in the form of pulses generated other than in continuous form like analog signals. PWM can be generated by making use of a comparator. Modulating and the Sawtooth signals are compared and the PWM signal is generated at the output. 1). Average power is reduced by using ______? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 2). In what technique the signal’s energy is distributed in the form of pulses? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint Read More about Pulse Amplitude Modulation 3). Percentage of the time at which signal is ON is referred to as _________? Input Cycle Output Cycle Duty Cycle Incoming Cycle None Hint 4). What is the Duty cycle if the signal is ON? 100 % 50% Zero Infinite None Hint 5). How Duty cycle is calculated? Turn ON Time/ (Turn ON Time + Turn OFF Time) Turn ON Time/ (Turn OFF Time) 1/ (Turn ON Time + Turn OFF Time) Turn ON Time None Hint 6). On what the average voltage value depends? Input Cycle Output Cycle Duty Cycle Incoming Cycle None Hint 7). On what basis does the value of average voltage get varied? By Controlling ON Pulse Width By Controlling OFF Pulse Width By Controlling ON & OFF Pulse Width By Controlling Duty Cycle None Hint 8). What determines how fast the period of PWM is complete? Duty Cycle Modulating Signal PWM Frequency Carrier Signal None Hint 9). How to calculate PWM Frequency? 1/ ON Time + OFF Time 1/ Time Interval a & b 1/OFF Time None Hint 10). For 5 Volts of Operating voltage & a Duty cycle is 50% what will be the voltage at output? 5 V 2.5 V 2 V 1V None Hint 11). What are the types present in Pulse Width Modulation? Trail Edge Modulation Lead Edge Modulation Pulse Center Two Edge Modulation All Mentioned Above None Hint 12). What conventional type of PWM has a fixed trail edge? Trail Edge Modulation Lead Edge Modulation Pulse Center Two Edge Modulation All Mentioned Above None Hint 13). What happens in Lead Edge Modulation? Trail Edge is Modulated Lead Edge is Modulated Both Edges are Modulated Trail Edge is Fixed None Hint 14). What is fixed in Pulse Center Two Edge Modulation? Trail Edge Lead Edge Pulse Center Both Edges None Hint 15). What type of signals are generated from discrete devices using PWM controlling technique? Analog Signals Digital Signals Binary Signals Discrete Signals None Hint 16). How the signal is switched between low and high voltages described using? Duty Cycle Modulating Signal PWM Frequency Carrier Signal None Hint 17). What determines the signal stays for a certain time at the high voltages? Duty Cycle Modulating Signal PWM Frequency Carrier Signal None Hint 18). How to generate PWM signals simply? Using Intersection Method Using Constructive Method a & b Using Instructive Method None Hint 19). What is required to generate PWM signals? Modulating Signal Sawtooth or Triangular Waveform Comparator All Mentioned Above None Hint 20). What happens if the reference signals value is greater than modulated signals? PWM at High State PWM at Low State Doesn’t Change Fluctuates among High & Low None Hint 21). For control of PWM, what happens in the Delta-sigma modulation? Output Signal Subtracted from Reference Signal Output Signal Added to Reference Signal Output Signal Multiplied to Reference Signal Output Signal Divided with Reference Signal None Hint 22). For control of PWM, what happens in the Delta modulation? Output Signal Subtracted from Reference Signal Output Signal Added to Reference Signal Output Signal Multiplied to Reference Signal Output Signal is Integrated None Hint 23). What happens if the signal at output reaches either of the limits in Delta modulation? PWM Changes State PWM Remains at High State PWM Remains at Low State PWM Reaches Zero None Hint 24). What happens if the error of integral exceeds limits in Delta-sigma Modulation? PWM Changes State PWM Remains at High State PWM Remains at Low State PWM Reaches Zero None Hint 25). What is used in Multi-phase AC Generation? Delta Modulation Delta-sigma Modulation Space Vector Modulation a & b None Hint Pulse Width Modulation MCQs for Quiz 26). What happens if the value of counter increased than the reference? PWM Changes State PWM Remains at High State PWM Remains at Low State PWM Reaches Zero None Hint 27). How is the process of converting PWM? Linear Non-Linear Straight Direct None Hint 28). Any band limit of baseband signals within the range of ±0.637 is ______? Pulse Width Modulated Wave Amplitude Modulated Wave Frequency Modulated Wave Phase Modulated Wave None Hint 29). PWM Power controlled systems can be realized using ______? Semiconductor Switches Timers Counters Comparators None Hint 30). If the value at the counter is greater than the reference PWM changes its state is known as ________? Time Proportioning Time Inverse Time Control Time Reflux None Hint 31). Computer controllers of a fan of varying speed use _______? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 32). Which class of audio amplifiers based on the principle of PWM? Class A Class B Class C Class D None Hint 33). Field-Gradient coil present in machines of MRI gets driven by ________? High Power PWM Amplifiers Low Power PWM Amplifiers Low Voltage PWM Amplifiers Low Current PWM Amplifiers None Hint 34). In PC speakers, that playback PCM sounds (digital) uses _______? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 35). Direct stream digital encoding of sound use ________? Pulse Density Modulation Delta Modulation Space-vector Modulation Delta-sigma Modulation None Hint Pulse Width Modulation MCQs for Exams 36). Sine-Triangle Pulse width Modulation is the signals utilized in _______? Class A Amplifiers Direct Stream Digital Encoding Micro-Inverter Design Soft-Blink LEDs None Hint 37). Light Dimmers uses _______? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 38). What type of modulation controls the power delivered to load? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 39). Maximum Power point Tracking can be achieved using ________? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 40). What prevents LED overheating? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 41). _________ have faster timing response? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 42). Pulse Width Modulation technique have _______ Power factor. High Input High Output Low Input Low Output None Hint 43). What helps the motor to generate maximum amount of torque? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 44). Switching losses because of Pulse Width Modulation is? High Low Moderate Can't Say None Hint 45). Radio frequency interference induced due to _______? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint Pulse Width Modulation MCQs for Interviews 46). What in controlling devices made of semiconductors? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 47). What controls fan present in the CPU of a computer? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 48). What are the advantages of using Pulse Width Modulation? High Efficiency Less Power Loss Controls Power Precisely All Mentioned Above None Hint 49). What used for Encoding purposes in telecommunications? Pulse Width Modulation Continuous Wave Modulation Angular Modulation Demodulation None Hint 50). Pulse Width Modulation can be used in _________? Audio Amplifiers Video Amplifiers Voltage Regulation All Mentioned Above None Hint For More MCQs Phase Modulation Question & Answers Digital Modulation Question & Answers Demodulation Question & Answers Sampling Theory and Pulse Modulation Question & Answers Frequency Modulation Question & Answers Amplitude Modulation Question & Answers Modulation Question & Answers Please fill in the comment box below. Time's up
