Flip Flops Question & AnswersMay 18, 2021 By WatElectronics This article lists 100 Flip Flop MCQs for engineering students. All the Flip Flop Questions & Answers given below includes solution and link wherever possible to the relevant topic.In a sequential circuit design, flip-flops are the basic building blocks. In a short or in a very simple way we can say that flip flop is on and off. The sequential circuit is generally a combinational circuit with memory. The flip flop stores only binary data that has two states they are logic 1 and logic 0. The set-reset, JK, delay, and trigger or toggle are the most commonly used flip flops. 1). The output of the sequential circuit depends upon _________Present inputPast inputPresent input and present stateNone of the aboveHintThe output of the sequential circuit depends upon present input and present state (past output) 2). The flip flops are categorized into ________OneTwoThreeFourHintThe flip flops are categorized into four types they are set-reset, trigger or toggle, delay, and J-K flip flop 3). What is the standard form of S-R flip flop?Set ResetSimple-ResetSingle-ResetNone of the aboveHintThe standard form of S-R flip flop is a set-reset flip flop 4). When the set is enabled in S-R flip flop then the output will be __________SetResetNo changeIndeterminateHintWhen the set is enabled in S-R flip flop then the output will be set means one 5). When the set is disabled and reset is enabled in S-R flip flop then the output will be __________SetResetNo changeIndeterminateHintWhen the set is disabled and reset is enabled in S-R flip flop then the output will be reset means zero 6). When both set and reset are disabled in S-R flip flop then the output will be __________SetResetNo changeIndeterminateHintWhen set and reset neither them are enabled then there will be no change means the previous output will be the present output 7). When both set and reset are enabled in S-R flip flop then the output will be __________SetResetNo changeIndeterminateHintWhen both set and reset are enabled in S-R flip flop then the output will be in Indeterminate condition that is known as a race condition 8). In which flip flop the present input will be the next output?S-RJ-KDTHintIn D-flip flop the present input will be the next output 9). The J-K flip flops has ___________ memoryTemporaryRandomNonrandomTrueHintThe J-K flip flops have a true memory 10). The preset input is used to make output ______Q=1Q=0InvalidNo changeHintThe preset input is used to make output Q=1 11). The clear input is used to make output ______Q=1Q=0InvalidNo changeHintThe clear input is used to make output Q=0 12). The preset and clear inputs don’t need synchronization?TrueFalseHintYes, the preset and clear inputs both doesn’t need synchronization 13). When preset=0, clear=1 then the output will be ________OneZeroNot usedFF operationHintWhen preset=0, clear=1 then the output will be one 14). When preset=1, clear=0 then the output will be ________OneZeroNot usedFF operationHintWhen preset=1, clear=0 then the output will be zero 15). There are total ______ steps for flip flop conversionsOneTwoThreeFiveHintThere are total of five steps for flip flop conversions they are not available required flip flop, write characteristics table of required F/F, write excitation table of available F/F, solve Boolean expression and draw circuit 16). In SR to JK flip flop conversion which one is an available flip flop?SRJKTBoth SR and JKHintIn SR to JK flip flop conversion, SR flip flop is an available flip flop 17). In SR to JK flip flop conversion which one is a required flip flop?SRJKTBoth SR and JKHintIn SR to JK flip flop conversion JK flip flop is required flip flop 18). The shift registers are categorized into ________OneTwoThreeFourHintThe shift registers are categorized into four types they are SISO, PIPO, SIPO, and PISO 19). How many possible conversions are there to convert SR flip flop to other flip flops?OneTwoThreeFourHintThe SR flip flop convert into other flip flops in three ways they are SR to JK, T, and D flip flop 20). A flip flop is an __________Edge sensitive deviceSynchronous deviceBoth a and bNone of the aboveHintA flip flop is an edge-sensitive and synchronous device 21). The operation of the flip flop is slow?TrueFalseHintYes, the operation of the flip flops are very slow compared to latches that are only due to the clock signal 22). How many types of latches are there?OneTwoSixFourHintThere are six types of latches are there they are SR, gated SR, D, gated D, JK, and T latch 23). The flip flop requires _________More number of gatesMore powerBoth a and bNone of the aboveHintThe flip flop requires more gates and power when compared to latches 24). _________ are the applications of flip flopRegistersCountersStorage devicesAll of the aboveHintThe registers, counters, storage devices, frequency dividers, etc are the applications of flip flop 25). Does the flip flop based on enable function input?TrueFalseHintNo, the flip flops don’t base on enabling function input it based on clock pulsesFlip-Flops Important Questions with Hints 26). The flip flops works with ________Binary inputsClock signalBoth a and bNone of the aboveHintThe flip flop works with both clock signal and binary inputs 27). The flip flop can’t be used as a register is it true?TrueFalseHintNo, the flip flops can be used as a register 28). What is the standard form of T flip flop?TriggerToggleTrigger or toggledNone of the aboveHintThe standard form of T flip flop is a trigger or toggle flip flop 29). The JK flip flop convert to other flip flops in ________?One-wayTwo waysThree waysFour waysHintThe JK flip flop convert into other flip flops in three ways they are JK to SR, T, and D flip flop 30). How many types of triggers are there?One typeTwo typesThree typesFour typesHintThere are three types of triggers are there they are edge, level, and pulse triggering 31). When S=0, R=0, CLK=X then the output will be ___________No changeSetResetInvalidHintWhen S=0, R=0, CLK=X then there will be no change in the output 32). When reset is low and set is high in a NOR D-latch table then the output will be __________No changeHighLowInvalidHintWhen reset is low and set is high in a NOR D-latch table then the output will be high 33). When reset is high and set is low in a NOR D-latch table then the output will be __________No changeHighLowInvalidHintWhen reset is high and set is low in a NOR D-latch table then the output will be low 34). When reset is high and set is low in a NAND D-latch table then the output will be __________No changeHighLowInvalidHintWhen reset is high and the set is low in a NAND D-latch table then the output will be low 35). When reset is low and set is high in a NAND D-latch table then the output will be __________No changeHighLowInvalidHintWhen reset is low and the set is high in a NAND D-latch table then the output will be high 36). Which circuit doesn’t have a memory unit?CombinationalSequentialBoth a and bNone of the aboveHintThe combinational circuit doesn’t have a memory unit whereas the sequential circuit has a memory unit 37). ________ is an example for sequential circuitFlip flopFull adderHalf adderNone of the aboveHintThe flip flop is an example of a sequential circuit 38). _______ is an example for combinational circuitFlip flopRegisterMultiplexerNone of the aboveHintThe multiplexer is an example of a combinational circuit 39). How many possible conversions are there to convert T flip flop to other flip flops?One wayTwo waysThree waysFour waysHintThe toggle or trigger flip flop convert to other flip flops in three ways they are T to JK, SR, and D flip flop 40). What is the standard form of D flip flop?DataDeterministicDelayNone of the aboveHintThe standard form of D flip flop is delay flip flop 41). How many inputs does the RS latch have?One inputTwo inputsThree inputsFour inputsHintThe RS latch has two inputs they are set and reset 42). When triggers on high clock level then this type of trigger is known as ________High levelLow levelPositive levelNegative levelHintWhen triggers on high clock level then this type of trigger is known as high-level triggering 43). When triggers on low clock level then this type of trigger is known as ________High levelLow levelPositive levelNegative levelHintWhen triggers on low clock level then this type of trigger is known as low-level triggering 44). The flip flops require ________More powerMore areaLess powerBoth a and bHintThe flip flops require more area and more power compare to latches 45). The type of operation performed by flip flop is _______SynchronousAsynchronousBoth a and bNone of the aboveHintThe type of operation performed by flip flop is synchronous 46). The type of operation performed by latches is _______SynchronousAsynchronousBoth a and bNone of the aboveHintThe type of operation performed by latches is asynchronous 47). The flip flop is a _______ deviceUnstableBi-stableBoth a and bNone of the aboveHintThe flip flop is a bi-stable device that is used to store either o or 1 48). In which year the first flip flop was invented?1915191619171918HintIn 1918 the first flip flop was invented 49). How many possible conversions are there to convert D flip flop to other flip flops?One-wayTwo waysThree waysFour waysHintThe Delay flip flop convert into other flip flops in three ways they are D to JK, T, and SR flip flop 50). Who invented first flip flop?F.W.JordanWilliam EcclesHaraldBoth a and bHintThe first flip flop was invented by F.W.Jordan and William Eccles Read more about FlipflopsFlip-Flops Important Questions for Engineering Students 51). The set-reset flip flops constructed by cross-coupling of ______ gatesAND or NANDNAND or NORXNOR or NORNone of the aboveHintThe set-reset flip flops constructed by cross-coupling of NAND or NOR gates 52). The sequential circuits are categorized into _______OneTwoThreeFourHintThe sequential circuits are categorized into two types they are synchronous and asynchronous sequential circuits 53). How many inverters does the basic latch consists of?OneTwoThreeFourHintThe basic latch consists of two inverters 54). How many additional AND gates does SR flip flop consists of?OneTwoThreeFourHintThe set-reset flip flop consists of two AND gates at the set and resets inputs of the S-R latch 55). The J-K flip flop characteristic similar to _________ flip flopD flip flopT flip flopS-R flip flopNone of the aboveHintThe J-K flip flop characteristic similar to set-reset flip flop 56). The latch is a __________ deviceUnstableBistableBoth a and bNone of the aboveHintThe latch is a bi-stable device that is used to store either o or 1 57). When toggle condition occurs in JK flip flop?J=1, K=1J=0, K=0J=1, K=0J=0, K=1HintWhen both J and K inputs are high then their toggle condition occurs 58). The no-change conditions occur when ________ in JK flip flopJ=1, K=1J=0, K=0J=1, K=0J=0, K=1HintThe no-change condition occurs when J=0, K=0 in JK flip flop 59). The flip flop are categorized into _______ typesOneTwoThreeFourHintThe flip flop is categorized into four types they are SR, D, JK, and T flip flops 60). How many outputs does D-flip flop have?OneTwoThreeFourHintThe D-flip flop has only one output 61). When the clock input is low in a D flip flop then the input of the D flip flop is _______HighLowNo effectNone of the aboveHintWhen the clock input is low in a D flip flop then there is no change in the delay input 62). When the clock input is high and D input is high then the output of a D flip flop will be _______HighLowNo effectNone of the aboveHintWhen the clock input is high and D input is high then the output of a D flip flop will be low 63). The combinational circuit have ____________ number of stable statesOneTwoThreeFourHintThe combinational circuit has two stable states they are zero and one 64). How many inputs does D flip flop have?OneTwoThreeFourHintThe D flip flop has only one input 65). The flip flops are activated by _____________ triggerOnly positive edgeOnly negative edgeEither positive or negative edgeNone of the aboveHintThe flip flops are activated by either positive or negative edge trigger 66). The RS flip flop input clock is given to _______OutputInputBoth a and bPulseHintThe RS flip flop input clock is given to pulse 67). How many NAND gates does the D flip flop circuit consists of?OneTwoThreeFourHintThe D flip flop circuit consists of four NAND gates 68). The inputs of the SR, JK, and D flip flop are the _____ inputsBidirectionalUnidirectionalSynchronousAsynchronousHintThe inputs of the SR, JK, and D flip flop are the synchronous inputs Read more about Gates 69). The counters are categorized into ______OneTwoThreeFourHintThe counters are categorized into three types they are asynchronous/synchronous modulus, and single & multimode 70). How many states does the decimal counter have?OneTenThreeFourHintThe decimal counter has ten states 71). The synchronous counter is one type of _______ counterSSILSIVLSIMSIHintThe synchronous counter is one type of medium-scale integrated counter 72). The BCD is one type of counter which is also known as __________SynchronousAsynchronousParallelDecadeHintThe BCD is one type of counter which is also known as a decade counter 73). The counter circuit parallel outputs represent _________Clock countSerial data wordParallel data wordNone of the aboveHintThe counter circuit parallel outputs represent clock count 74). How many of states are there in a 4 bit counter?OneFourEightSixteenHintThe number of states in a four-bit counter is 16 75). An IC 7493 is a______ bit binary ripple counterOneFourEightSixteenHintAn IC 7493 is a four-bit binary ripple counterFlip-Flops Important Questions for Interviews 76). How many JK master-slave flip flops are required for IC 7493?OneFourEightSixteenHintIC 7493 required four JK master-slave flip flops 77). Which IC is a decade counter?IC 7490IC 7491IC 7492IC 7493HintAn IC 7490 is a decade counter 78). How many pins does ripple counter IC have?481214HintThe ripple counter IC has 14 pins Read more about Counters 79). __________ type of counter counts in an upward mannerUp counterDown counterDecade counterNone of the aboveHintThe up counter is a type of counter which counts in an upward manner 80). In which manner does down counter count?UpwardDownwardBoth a and bNone of the aboveHintThe down counter counts in a downward manner 81). The high-speed counter is a __________ type of counterDecade counterSynchronous counterAsynchronous counterNone of the aboveHintThe high-speed counter is a synchronous type of counter 82). The another name for fundamental mode is ____________ClockEdgePulseNone of the aboveHintThe other name for fundamental mode is pulse operation 83). Is it true that the up-down counter is a combination of latches and flip-flops?TrueFalseHintNo, the up-down counter is a combination of latches and flip flops, it is a combination of up and down counter 84). How many of states are there in a 3 bit counter?OneFourEightSixteenHintThe number of states in a three-bit counter is 8 85). Which one is also called as a multimode counter?Decade counterSynchronous counterAsynchronous counterUp and down counterHintThe up and down counter is also called a multimode counter 86). __________ is a truncated modulus exampleModulus-9Modulus-15Modulus-11All of the aboveHintModulus-9, 11, and 15 is a truncated modulus example 87). Is register is a type of combinational circuit?TrueFalseHintNo, the register is not a type of combinational circuit, it’s a type of sequential circuit 88). What is the standard form of SISO?Serial Input Serial OutputSerial Output Serial InputSimple Input Serial OutputNone of the aboveHintThe standard form of SISO is Serial Input Serial Output 89).What is the standard form of PIPO?Parallel Input Parallel OutputParallel Output Serial InputSimple Input Serial OutputNone of the aboveHintThe standard form of PIPO is Parallel Input Parallel Output 90). The Johnson and ring shift counters are _________ type of countersBinarySynchronousAsynchronousNone of the aboveHintThe Johnson and ring shift counters are the synchronous type of counters 91). Does an IC 74HC195 use for all SISO, PIPO, SIPO, and PISO operations?TrueFalseHintYes, an IC 74HC195 used for all SISO, PIPO, SIPO, and PISO operations 92). How many bits of information do flip-flop store?One-bitTen-bitTwo-bitThree-bitHintThe flip flops store only one bit of information 93). The very large scale integration chip is made up of _______BICMOS, CMOSBJT, NMOSBoth a and bNone of the aboveHintThe very large scale integration chip is made up of BICMOS, CMOS, BJT, and NMOS 94). How many of states are there in a 2 bit counter?OneFourEightSixteenHintThe number of states in a two-bit counter is 4 95). What is the standard form of SOSI?Serial Input Serial OutputSerial Output Serial InputSimple Input Serial OutputNone of the aboveHintThe standard form of SOSI is Serial Output Serial Input 96).What is the standard form of POSI?Serial Input Serial OutputParallel Output Serial InputSimple Input Serial OutputNone of the aboveHintThe standard form of POSI is Parallel Output Serial Input 97). Read-only memory consists of _______ arraysOR arrayNAND arrayBoth a and bNone of the aboveHintRead-only memory consists of both NAND and OR arrays 98). What is the available flip flop in T to D flip flop conversion?D flip flopT flip flopS-R flip flopNone of the aboveHintThe available flip flop in T to D flip flop conversion is T flip flop 99). What is the required flip flop in T to D flip flop conversion?D flip flopT flip flopS-R flip flopNone of the aboveHintThe required flip flop in T to D flip flop conversion is D flip flop 100). What is the required flip flop in JK to D flip flop conversion?D flip flopT flip flopS-R flip flopNone of the aboveHintThe required flip flop in JK to D flip flop conversion is D flip flop Time is Up!
