Latches Question & AnswersOctober 18, 2021 By WatElectronics This article lists 100 Latches MCQs for engineering students. All the Latches 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, interviews, or professionals who would like to brush up their fundamentals on Latches.A bistable device like a latch is a temporary storage device that includes two stable states. As compared to flip flops, Latches are extremely related because they too include two stable states. In flip-flops, feedback is used to connect the outputs toward the opposite inputs. The main difference between these two is the technique used for modifying their state. A latch verifies all its inputs constantly & the output alters instantly because there is a change within the input. Therefore latches are applicable in asynchronous sequential logic circuits. 1). Latches includes...?InvertersInductorsFrequency generatorsTiming generatorsHintThe output provided by this circuit is quite opposite to its input 2). Which of the following is the best example of Latch?Astable multivibratorMonostable multivibratorBistable multivibratorNone of the aboveHintIt includes two stable states 3). How many of the stable states do a Latch can include?1-stable state2-stable states3-stable statesNone of theseHintIt is equal to the stable states used in bistable multivibrator 4). Why latch is called a memory device?It includes 4 bits of internal memoryIt can store 1-bit of dataIt can share 8-bits of dataNone of the aboveHintIt stores single bit of data 5). What are the two stable states of latches?Monostable and AstableHigh output & Low inputHigh input & Low outputLow output & High outputHintMinimum and maximum outputs 6). The types of latches are2468HintThe types are ranges from < 5 > 3 7). What is S & R in SR-latch?System RatedSet ReadySet ResetNone of the aboveHintThese are used to set and reset the signals 8). The inputs of an SR latch includes?1 input2 inputs4 inputs8 inputsHintThe inputs are S & R 9). When both SR latches inputs are high, then the latch will goStableUnstableMetastableNone of the above mentionedHintParticular excited state of a system that has a longer lifetime 10). The working of the NAND latch includes...?When both the inputs are 1When both the inputs are 0When both the inputs are invertedWhen both the inputs don't careHintWhen the inputs are high 11). The analysis process of SR latch primary step is to..?Label statesLabel tablesLabel inputsLabel outputsHintWhen the outputs are label 12). A feedback loop which can be formed in latch by Inverters is constantly...?ChangingInfinitePositiveNegativeHintWhen inverters are changing constantly 13). Latch as one with a triggering circuit can form a...?InductorTiming generatorFlip flopSine generatorHintThe short form of this is "FF'' 14). Which of the following doesn't contain a latch?InverterState outputState inputClockHintIt is also called as clock signal 15). The example of a level-triggered device is?JL FFSR FFLatchesS FFHintThese are used to store the information 16). Which of the subsequent latch is NOT a latch?JK latchGated D-LatchSR latchGated SR latchHintThis is one type of flip flop 17). The invalid condition for SR-Latch happens as both the S & R are...?When S = high, & R = lowHighWhen S = low, & R = highLowHintWhen the set and reset are maximum 18). Which of the following circuit is another name of the sequential circuit?LatchStrobeFlip-flopNone of the aboveHintIt is also known as bistable multivibrator 19) Which of the following operations are faster?Flip-flopsSequential circuitsCombinational circuitsLatchesHintThese circuits uses different logic gates 20). The SR-Latch inputs are...?X &YS & RA & BJ & KHintThese are also known as set and reset 21). The SR latch outputs are...?Q & Q’X & YA & BS & RHintThe outputs are high and low 22). When NAND latch works?When both inputs are lowWhen both inputs are highWhen inputs are invertedNone of the aboveHintWhen both inputs of NAND latch is 1 23). The essential devices in Latches…?ResistorsDiodesInvertersTiming GeneratorsHintThese are also called AC drives 24). Which of the following device is used to interface o/p devices?FFSEncodersLatchesMultiplexersHintThe device which has two stable states 25). The latch working mainly depends on?CLK levelEdgeMemoryTimeHintWhen the CLK is high, then all the input effects will come into view on o/p.MCQs on Latches for Interviews 26). In SR-Latch when the invalid state takes place?When the inputs are lowWhen the inputs are highWhen S is high and R is lowWhen S is low and R is highHintWhen S & R are high 27). Which of the following FF can be used like a Latch?T-FFD-FFSR FFJK FFHintThis type of FF uses delay within input using one CLK cycle Please refer to this link to know more about Flip Flops 28). The present state in synchronous circuits can be determined through….?LatchesFlip FlopsCombinational Logic CircuitsMultiplexersHintIt is also called a bistable multivibrator 29). Unlocked FFs are also called?Combinational Logic CircuitsMultiplexersLatchesLogic GatesHintIt depends on input to change its output 30). Latch circuit works on …states based on the triggering signals?2345HintThe states are active low and active high 31). When enable pin of the latch is high then both the inputs are…..?HighLowMediumNo changeHintWhen the enable pin is low then both the inputs are high. 32). What are the inputs of a Latch?High & :LowSET and RESET0 & 1A & BHintThe outputs will be Q Q’ 33). SR latch can be designed with…..logic gates?2 AND2 NOR2 Ex-OR2 NORHintThe function of this gate is quite opposite to the OR gate 34). The gated SR latch includes…..inputs?2345HintThe inputs are SET, RESET, and Enable pin 35). Which of the following pin enables the inputs of Gates SR Latch?Enable PinData PinRegister PinOutput Pin QHintThis pin enables the operation of both the inputs 36). Which of the following is used to connect the enable pin in Gated SR Latch?Logic GateSwitchTransistorDiodeHintIt interrupts the flow of current 37). Which of the following flip flop is similar to D latch?SRTDJKHintThe difference between this FF and latch is to enable pin 38). Gated D Latch includes…inputs?2345HintThe inputs are enabled and data 39). Which of the following latch is used to design a gated D latch?JkDGated SR LatchTHintThe inputs of this latch is SET & RESET 40). Which of the following latch is similar to the JK latch?DSRTGated SRHintIn this latch, there is no o/p feedback to the inputs 41). Which of the following latch can be formed by shortening the inputs of the JK latch?SRTDGated SRHintThis is also called toggle latch 42). When the T latch output will toggle?When the input is highLowInfiniteNone of the aboveHintWhen the input of the T latch is 1 43). How many types of latches are there in digital electronics?2468HintThey are D, SR, Gated SR, Gated D, T, and JK 44). Why is latch is called a bistable multivibrator?It includes two stable statesIts working is similar to multivibratorIt is a combinational circuitIt removes the stored dataHintThe two stable states are Low and High 45). In digital electronics systems, the basic building blocks are?Flip flops & LatchesLogic GatesIntegrated CircuitsMultiplexersHintThese circuits includes two stable states which are used to store the data 46). The example of a bistable multivibrator is….?LatchFlip FlopIntegrated CircuitsLogic GateHintBoth the latch and bistable multivibrator includes two stable states. 47). Flip flops & latches are the basic building blocks of……?EncodersSequential CircuitsIntegrated CircuitsDecodersHintThe output of these circuits depends on the input timing 48). Latches can be designed by using….?EncodersLogic GatesICsMultiplexersHintA physical electronic device that is used to implement a Boolean function. 49). Latches are used to built…?Flip FlopsLogic GatesEncodersDecodersHintIt is used to store a 1-bit data 50). Logic gates can be built with…?Flip FlopsTransistorsEncodersMultiplexersHintA semiconductor device is used to switch/amplify electronic signals Please refer to this link to know more about Logic GatesMCQs on Latches for Exams 51). Which of the following has positive feedback…..?TransistorsEncodersLatchMultiplexersHintIt is mainly used to store state data 52). Which of the following doesn’t include a latch?MemoryCLK signalLogic GatesEnableHintThis can be generated through a CLK generator 53). How can we design a circuit without using logic gates and that are not combinational?Using FeedbackOscillatorInverterNoneHintBy creating loops within the circuit 54). If the feedback in the circuit is positive then it tends to include…?SignalsStable StatesEnable PinInverterHintA latch includes high output & low output 55). The feedback loop which is formed in a latch by an inverter is always…..?NegativeInfinitePositive AlwaysChangingHintIt exacerbates the results of a small trouble 56). Which of the following is a popular microprocessor chip?74LS33774LS37374LS27874LS120HintIt is an octal latch chip Please refer to this link to know more about Microprocessor 57). A switch debouncing can be possible by using a…….?IntegratorSR LatchD Flip FlopMultiplexerHintIt is an asynchronous device 58). Which of the following is cross-coupled to make an SR latch with an active high i/p?2 AND gates2 OR Gates2 NOR Gates2 NOT GatesHintThe o/p of this gate is positive when two inputs are negative 59). Which of the following statement is correct?A FF is edge-triggeredA FF is level triggeredA latch is not level triggeredA latch edge-triggeredHintFF is an alteration to the latch 60). Which of the following is one of the drawbacks of a latchChance of metastabilityExpensiveSensitiveHas many stable statesHintWhenever a latch is level-sensitive then it is caused 61). As compared to FFs, the latch design is ….?HardVery flexibleNot easyComplicatedHintLatch design in digital electronics is easy 62). Latch occupies very less area because of….?Its size is smallNano DesignIt uses fewer flip flops to designNone of the aboveHintIts shape is very small 63). In high-speed circuit design, the latch performance is….?Very quickSlowMediumVery slowHintLatches are asynchronous within the design of high-speed circuits 64). Which of the following is the main benefit of a latch?Latches use fewer componentsVery speed operationUses more logic gatesIt borrows required time to complete the circuit design if the design is not completed in timeHintIf the circuit design is not finished in the set time they take time from others 65). In which of the following, the circuit analyzing is difficult?LatchesFlip FlopsMultiplexersDemultiplexersHintBecause latches have level-sensitive property 66). The testing of the latch circuit can be done by using…..?MultimeterAdditional CAD programSimmulationVoltmeterHintIt uses an extra CAD program to test the circuit 67). In asynchronous systems, which of the following latch is used?T LatchD LatchSR LatchJK LatchHintThese latches are used as input and output ports 68). In synchronous 2-phase systems, which latches are used?SR LatchD LatchT LatchJK LatchHintFor decreasing the transit count these latches are used 69). Single bit storage elements are called?Flip FlopsLatchesLogic GatesEncodersHintThese are used to store the data and computing 70). Which of the following latch is similar to RS?D LatchT LatchJK latchGated SR LatchHintIn RS latch, the o/p feedback is not present 71). Which of the following latch is modified to form a gated D-latch?T LatchD LatchSR latchGated SR LatchHintIn this latch, the R input should be changed to an inverted S 72). When the JK latch inputs are shorted then which of the below latch is formed?T LatchSR latchD LatchGated SR LatchHintWhen the input of this latch is high then the output will be toggled 73). Why latches don’t work as a register?Lack of a CLK SignalMemoryBinary InputsOutputsHintLatches doesn’t include a CLK signal 74). Sequential circuits are available in ….types?2456HintThey are synchronous and asynchronous 75). In sequential circuits, which of the following element provides memory?EncoderDecoderCombinational Logic CircuitFlip FlopHintA memory device that stores a single data bitLatches MCQs for Quiz 76). At the end of bits in a shift register has……neighbors?2468HintShift register has two neighbors at the end of the bit 77). SR latches are also known as…?D Flip FlopsDirect Coupled RS FFsMultiplexersNone of aboveHintIt has two inputs like SET/RESET 78). How a NAND-based SR latch is changed into an SR latch?By arranging a D-latch at every i/pBy arranging an inverter at every i/pBoth an inverter & a latch at its i/pNone of the aboveHintBy connecting a latch and an inverter at its input 79). Which of the following circuits have quick operations?Flip FlopsCombinational CircuitsLatchesMultiplexersHintIn these circuits, different logic gates can be used 80). In SR latch based on NAND gate, when the S=R=1 then what is the condition of the latch?Outputs will be lowOutputs will be highResetNo changeHintThere is no change within the latch condition 81). When SR Latch is designed with NAND gates then the circuit is called as….?Active low circuitActive high circuitCombinational circuitLogic circuitHintThis circuit activates through a -Ve level trigger 82). Which of the following latch is known as transparent latch?D LatchSK LatchT LatchNone of the aboveHintThis latch is known as a data latch 83). Which of the following circuits is known as two-state devices?Sequential logic circuitsLogic gate circuitsCombinational logic circuitsNone of the aboveHintThese circuits use memory elements 84). How many categories are there in sequential logic circuits?1357HintThe categories are event, CLK and pulse driven 85). Sequential circuits are signified with….?Infinite state machineFinite state machineMultiplexersEncodersHintIt is also called FSM 86). The storage elements that function through levels of the signal are known as…?Flip FlopsMultiplexersEncodersLatchesHintThese are used to design asynchronous sequential circuit 87). The output crossing in SR Latch is called as?CouplingCross-couplingInterfacingNone of the aboveHintThis circuit uses cross-coupling feedback 88). The amount of power used by latches is…..?LessHugeVery highNone of the aboveHintLatches works with very little power 89). Latches are better than….?MultiplexersFlip flopsLogic gatesEncodersHintTo get the quick realizations, these are very better 90). In digital electronics, memories are considered as…?Essential componentsStorage elementsDetachable elementsProtection devicesHintMemory in digital electronics is a very essential component 91). The working of latches mainly depends on…?Enable i/p functionBased on inputsBased on MemoryBased on Logic FunctionHintIt depends on the function of enable input Please refer to this link to know more about Digital Electronics MCQs 92). Transparent latches are used in….?Synchronous systemsAsynchronous systemsDigital systemsControl systemsHintThese systems are quite opposite to synchronous 93). Which of the following IC is a quadruple transparent latch?74HC7674HC7573HC2075HC40HintThese ICs are manufactured by Texas instruments 94). The series of 74HC75 latch is?7400 series74 series74H series7H seriesHintThese are digital logic ICS 95). The first electronic FF was invented by….?William GeorgeWilliam JoulsWilliam EcclesLindleyHintHe is the British physicists 96). The electronic FF was invented in which year?1920191019281918HintIt was invented by two scientists namely William Eccles & F. W. Jordan 97). In which of the following circuits, the o/p is mainly dependent on the present input?Combinational circuitsSequential circuitsLogic circuitsMultiplexersHintThese circuits don’t have a memory element 98). In which of the following circuits, the o/p depend on the history of input?Sequential circuitsCombinational circuitsLogic circuitsMultiplexersHintThese circuits have the least single memory element 99). Which of the following device is a temporary storage device?Flip flopLogic gatesLatchMultiplexersHintThese devices include two stable states 100). What is the property of a latch?Level SensingMemory StorageVoltage DetectionTriggeringHintBecause of this property, circuit analyzing is hard Time is Up! Time's up
