Demultiplexer Question & AnswersApril 1, 2022 By WatElectronics This article lists 50 Demultiplexer MCQs for Engineering Students. All the Demultiplexer Questions & Answers given below includes solution and link wherever possible to the relevant topic. This is helpful for users who are preparing for their exams, interviews, or professionals who would like to brush up their fundamentals on the demultiplexer.The demultiplexer is a combinational circuit having one input and many outputs, depending upon the selected inputs the single input transfer to any of the multiple-output. The demultiplexers have the reverse operation as compared to the multiplexer, in the case of multiplexers we have many inputs but single output. The demultiplexers are commonly used in data and clock demultiplexing, memory addressing, four-phase clock generator, switch encoding, serial to parallel converter, etc. The demux has many outputs, enable input and data input.The enable input in demultiplexers decides whether the circuit has to operate or not. If the enable is zero or low the circuit will not be operational and will get zero at all the output terminals, if the enable input is high then the demultiplexer is and data is transferred to any of the output depending on the selected input. The advantage of demultiplexers are they are used as decoders in security systems and increases the communication system efficiency and the disadvantage of demultiplexer is wastage of bandwidth may occur and delay may occur due to synchronization of signals.1). Which one of the following is known as a data distributor? Demultiplexer Decoder Multiplexer All of the above HintThe multiplexer is not a data distributor, it’s a data selector2). Which one of the following is a digital switch? Demultiplexer Multiplexer Both a and b None of the above HintThe demultiplexers acts as a digital circuit3). Which one of the following follows the combinational logic type? Demultiplexer Multiplexer Both a and b None of the above HintThe demultiplexer is a data distributor whereas the multiplexer is a data selector Read more about Combinational Logic Circuit4). Which one of the following works on one to many operational principles? Demultiplexer Multiplexer Both a and b None of the above HintThe multiplexers works on many to one operational principle5). Which one of the following has single data input and n data outputs? Demultiplexer Multiplexer Both a and b None of the above HintThe multiplexers are opposite to demultiplexers, it has n data inputs and one data output6). Where do the demultiplexers use? Receiver Transmitter Both a and b None of the above HintThe multiplexers used at the transmitter, are not used at the receiver7). Which one of the following is also known as data distributor and one to many circuits? Demultiplexer Multiplexer Both a and b None of the above HintThe demultiplexers have multiple outputs, one data input, and selected inputs8). The outputs in a multiplexer depends on _______________ input? Data Select Enable All of the above HintThe multiplexer output will change according to the change in the selected input9). When the enable input is zero, s1=0, S0=0 in the 1:4 demultiplexer then the outputs Y0, Y1, Y2, and Y3 are ________________ ? Y0=Y1=Y2=Y3=1 Y0=Y1=Y2=Y3=0 Y1=Y2=Y3=0, Y0=1 Y1=Y2=Y3=1, Y0=0 HintThe S1, S2 are selected inputs, Y0, Y1, Y2, and Y3 are outputs10). Which one of the following is a disadvantage of demultiplexer? Used as decoders Increases the communication system efficiency Wastage of bandwidth may occur All of the above Ans HintThe advantage of demultiplexers are used as decoders and increases the communication system efficiency11). Which one of the following demultiplexers requires only one select line? 1-to-2 demux 1-to-4 demux 1-to-8 demux 1-to-16 demux HintThe 1 to 2 demultiplexer consists of two output lines, one input, and one Select line12). Which one of the following is a type of combinational circuit? Demultiplexer Multiplexer Both a and b None of the above HintThe multiplexers accepts multiple inputs and the demultiplexers accepts a single input13). Which one of the following performs conversion from serial to parallel? Demultiplexer Multiplexer Both a and b None of the above HintThe technique of conversion in multiplexer is parallel to serial14). Which one of the following is an operating principle for demultiplexer? One to many Many to one Both a and b None of the above HintThe operating principle for demultiplexer is many to one15). How many 1 to 4 demux are used in the below block diagram? One Two Three Four HintThe I is the input bit, S0, S1 are select lines, and Y0 to Y7 are the outputsDemultiplexer MCQs for Interviews16). In which one of the following logic circuits the feedback loop is not present? Sequential logic circuit Combinational logic circuit Both a and b None of the above HintThe feedback loop is present in the sequential logic circuit17). In which one of the following logic circuits the combination of operands are not necessary? Sequential logic circuit Combinational logic circuit Both a and b None of the above HintIn sequential logic circuits the sequence of operands are necessary18). The finite state machine is an example for _________________ circuit? Sequential logic circuit Combinational logic circuit Both a and b None of the above HintThe finite state machine is an example of sequential logic circuit19). The encoder, multiplexers, decoder, demultiplexers are examples for __________________ logic circuit? Sequential logic circuit Combinational logic circuit Both a and b None of the above HintThe finite state machine is an example of sequential logic circuit20). In which one of the following logic circuits the memory element is not present? Sequential logic circuit Combinational logic circuit Both a and b None of the above HintThe memory elements are not present in combinational circuits it presents in sequential circuits21). Which one of the following logic circuits generates output based on past output and present input? Sequential logic circuit Combinational logic circuit Both a and b None of the above HintThe combinational logic circuit generates output only based on the present input22). Which one of the following is an example for demultiplexer? 16 input one output 8 inputs one output 1 input 16 outputs All of the above HintThe 16 input 1 output, 8 input 1 output are examples of multiplexers23). In which one of the following additional gates are included when designing? Demultiplexer Multiplexer Both a and b None of the above HintIn multiplexers, the additional gates are not required when designing24). The function of integrated circuit i.e IC 74x154 is ________________ ? Quad 2:1 mux Quad 4:1 mux 1:16 demux None of the above HintThe IC 74x154 is 1: 16 demux, it’s output is inverted input25). The figure shown below is a _______________ demux circuit diagram? 1 to 4 1 to 8 1 to 16 None of the above HintThe data D is the input bit, A and B are select lines, and Y0, Y1, Y2, & Y3 are the outputs26). Why do multiplexers behave as a data selector? N to one One to N Both a and b None of the above HintThe demultiplexers are one to N devices that’s why they behave as a data distributor27). The figure shown below is a block diagram of _______________ demultiplexer? 1 to 4 1 to 8 1 to 16 None of the above HintThe I is the input bit, S0, S1, S2 are select lines, and Y0 to Y15 are the outputs28). Which one of the following IC provides multiplexing? IC 74x159 C 74x156 IC 74x157 None of the above HintThe IC 74x157 and IC 74x156 provides demultiplexing29). The function of integrated circuit i.e IC 74x156 is ________________ ? Quad 2:1 mux Dual 1:4 demux 1:16 demux None of the above HintThe IC 74x156 is a dual 1:4 demux, its output is open collector30). Which one of the following is known as a data selector? Demultiplexer Decoder Multiplexer All of the above HintThe demultiplexer is also known as a data distributorDemultiplexer MCQs for Quiz31). Which one of the following demultiplexers requires only two select lines? 1-to-2 demux 1-to-4 demux 1-to-8 demux 1-to-16 demux HintThe 1 to 4 demultiplexer consists of four output lines, one input, and two Select lines32). The one input eight outputs is an example for ________________ ? Demultiplexer Multiplexer Both a and b None of the above HintThe demultiplexers are types of combinational logic circuits33). The function of integrated circuit i.e IC 74x157 is ________________ ? Quad 2:1 mux Quad 4:1 mux Dual 2:1 mux None of the above HintThe output of the IC 74x157 is the same as the given input, this IC provides multiplexing34). The function of integrated circuit i.e IC 74x139 is ________________ ? Quad 2:1 mux Quad 4:1 mux Dual 1:4 demux None of the above HintThe IC 74x139 is a dual 1:4 demux, its output is inverted input35). The figure shown below is a _______________ demux block diagram? 1 to 4 1 to 8 1 to 16 None of the above HintThe data D is the input bit, S0, S1, & s2 are select lines, and Y0 to Y7 are the outputs36). Which one of the following is a demultiplexer IC? IC 74155 IC 74154 Both a and b None of the above HintThe IC 74155 and Ic 74154 both are demultiplexers Ic's performs 1 to 4 and 1 to 16 demux operations37). The figure shown below is a _______________ demux circuit diagram? 1 to 4 1 to 8 1 to 16 None of the above HintThe data D is the input bit, A, B, C, D are select lines, and Y0 to Y15 are the outputs38). Which one of the following is an example for multiplexer? 16 input one output 8 inputs one output 1 input 16 outputs Both a and b HintThe one input sixteen outputs is an example for demultiplexer39). Which one of the following demultiplexers requires only five select lines? 1-to-2 demux 1-to-4 demux 1-to-8 demux 1-to-32 demux HintThe 1 to 32 demultiplexer consists of five select lines, the formula is 2^n40). Which one of the following is also known as a data selector and many to one circuit? Demultiplexer Multiplexer Both a and b None of the above HintThe multiplexers have multiple inputs and one outputDemultiplexer MCQs for Exams41). When the enable input is one, s1=0, S0=1 in the 1:4 demultiplexer then the outputs Y0, Y1, Y2, and Y3 are ________________ ? Y0=Y1=Y2=Y3=1 Y0=Y1=Y2=Y3=0 Y1=Y2=Y3=0, Y0=1 Y1=Y2=Y3=1, Y0=0 HintThe S1, S0 are selected inputs, Y0, Y1, Y2, and Y3 are outputs42). How many 1 to 4 demux are used in the below block diagram? One Two Three Four HintThe data D is the input bit, S0, S1 are select lines, and Y0 to Y7 are the outputs43). Which one of the following is an advantage of demultiplexer? Used as decoders Increases the communication system efficiency Wastage of bandwidth may occur Both a and b HintThe disadvantage of demultiplexer is wastage of bandwidth may occur and delay may occur due to synchronization of signals44). Which one of the following demultiplexers requires only three select lines? 1-to-2 demux 1-to-4 demux 1-to-8 demux 1-to-16 demux HintThe 1 to 8 demultiplexer consists of eight output lines, one input, and three Select lines45). When the enable input is one, s1=1, S0=0 in the 1:4 demultiplexer then the outputs Y0, Y1, Y2, and Y3 are ________________ ? Y0=Y1=Y2=Y3=1 Y0=Y1=Y2=Y3=0 Y0=Y1=Y3=0, Y2=1 Y1=Y2=Y3=1, Y0=0 HintThe S1, S2 are selected inputs, Y0, Y1, Y2, and Y3 are outputs46). The eight input one output is an example for ________________ ? Demultiplexer Multiplexer Both a and b None of the above HintThe multiplexers are types of combinational logic circuits47). Which one of the following performs conversion from parallel to serial? Demultiplexer Multiplexer Both a and b None of the above HintThe technique of conversion in demultiplexer is serial to parallel48). Which one of the following is an operating principle for multiplexer? One to many Many to one Both a and b None of the above HintThe operating principle for demultiplexer is one to many49). Which one of the following demultiplexers requires only four select lines? 1-to-2 demux 1-to-4 demux 1-to-8 demux 1-to-16 demux HintThe 1 to 16 demultiplexer consists of sixteen output lines, one input, and four Select lines50). When the enable input is one, s1=s0=1 in the 1:4 demultiplexer then the outputs Y0, Y1, Y2, and Y3 are ________________ ? Y0=Y1=Y2=Y3=1 Y0=Y1=Y2=Y3=0 Y0=Y1=Y3=0, Y2=1 Y0=Y1=Y2=1, Y3=1 HintThe S1, S2 are selected inputs, Y0, Y1, Y2, and Y3 are outputs Read more about Demultiplexer Please fill in the comment box below. Time is Up! Time's up