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.There are different types of latches available like SR Latch, D latch. Gated S-R Latch, JK Latch, Gated D Latch, and T Latch. So based on the applications, the type of latch is used in different circuits. The applications of latches mainly include; these are memory elements used to store the data in bits form. These are used widely for storing the data as well as the codes for computations. These are used as storage devices in power gating and clock circuits.1). Latches includes...? Inverters Inductors Frequency generators Timing generators HintThe output provided by this circuit is quite opposite to its input2). Which of the following is the best example of Latch? Astable multivibrator Monostable multivibrator Bistable multivibrator None of the above HintIt includes two stable states3). How many of the stable states do a Latch can include? 1-stable state 2-stable states 3-stable states None of these HintIt is equal to the stable states used in bistable multivibrator4). Why latch is called a memory device? It includes 4 bits of internal memory It can store 1-bit of data It can share 8-bits of data None of the above HintIt stores single bit of data5). What are the two stable states of latches? Monostable and Astable High output & Low input High input & Low output Low output & High output HintMinimum and maximum outputs6). The types of latches are 2 4 6 8 HintThe types are ranges from < 5 > 37). What is S & R in SR-latch? System Rated Set Ready Set Reset None of the above HintThese are used to set and reset the signals8). The inputs of an SR latch includes? 1 input 2 inputs 4 inputs 8 inputs HintThe inputs are S & R9). When both SR latches inputs are high, then the latch will go Stable Unstable Metastable None of the above mentioned HintParticular excited state of a system that has a longer lifetime 10). The working of the NAND latch includes...? When both the inputs are 1 When both the inputs are 0 When both the inputs are inverted When both the inputs don't care HintWhen the inputs are high11). The analysis process of SR latch primary step is to..? Label states Label tables Label inputs Label outputs HintWhen the outputs are label12). A feedback loop which can be formed in latch by Inverters is constantly...? Changing Infinite Positive Negative HintWhen inverters are changing constantly13). Latch as one with a triggering circuit can form a...? Inductor Timing generator Flip flop Sine generator HintThe short form of this is "FF''14). Which of the following doesn't contain a latch? Inverter State output State input Clock HintIt is also called as clock signal15). The example of a level-triggered device is? JL FF SR FF Latches S FF HintThese are used to store the information16). Which of the subsequent latch is NOT a latch? JK latch Gated D-Latch SR latch Gated SR latch HintThis is one type of flip flop17). The invalid condition for SR-Latch happens as both the S & R are...? When S = high, & R = low High When S = low, & R = high Low HintWhen the set and reset are maximum18). Which of the following circuit is another name of the sequential circuit? Latch Strobe Flip-flop None of the above HintIt is also known as bistable multivibrator19) Which of the following operations are faster? Flip-flops Sequential circuits Combinational circuits Latches HintThese circuits uses different logic gates20). The SR-Latch inputs are...? X &Y S & R A & B J & K HintThese are also known as set and reset21). The SR latch outputs are...? Q & Q’ X & Y A & B S & R HintThe outputs are high and low22). When NAND latch works? When both inputs are low When both inputs are high When inputs are inverted None of the above HintWhen both inputs of NAND latch is 123). The essential devices in Latches…? Resistors Diodes Inverters Timing Generators HintThese are also called AC drives24). Which of the following device is used to interface o/p devices? FFS Encoders Latches Multiplexers HintThe device which has two stable states25). The latch working mainly depends on? CLK level Edge Memory Time HintWhen the CLK is high, then all the input effects will come into view on o/p.MCQs on Latches for Interviews26). In SR-Latch when the invalid state takes place? When the inputs are low When the inputs are high When S is high and R is low When S is low and R is high HintWhen S & R are high27). Which of the following FF can be used like a Latch? T-FF D-FF SR FF JK FF HintThis type of FF uses delay within input using one CLK cycle Please refer to this link to know more about Flip Flops28). The present state in synchronous circuits can be determined through….? Latches Flip Flops Combinational Logic Circuits Multiplexers HintIt is also called a bistable multivibrator29). Unlocked FFs are also called? Combinational Logic Circuits Multiplexers Latches Logic Gates HintIt depends on input to change its output30). Latch circuit works on …states based on the triggering signals? 2 3 4 5 HintThe states are active low and active high31). When enable pin of the latch is high then both the inputs are…..? High Low Medium No change HintWhen the enable pin is low then both the inputs are high.32). What are the inputs of a Latch? High & :Low SET and RESET 0 & 1 A & B HintThe outputs will be Q Q’33). SR latch can be designed with…..logic gates? 2 AND 2 NOR 2 Ex-OR 2 NOR HintThe function of this gate is quite opposite to the OR gate34). The gated SR latch includes…..inputs? 2 3 4 5 HintThe inputs are SET, RESET, and Enable pin35). Which of the following pin enables the inputs of Gates SR Latch? Enable Pin Data Pin Register Pin Output Pin Q HintThis pin enables the operation of both the inputs36). Which of the following is used to connect the enable pin in Gated SR Latch? Logic Gate Switch Transistor Diode HintIt interrupts the flow of current37). Which of the following flip flop is similar to D latch? SR T D JK HintThe difference between this FF and latch is to enable pin38). Gated D Latch includes…inputs? 2 3 4 5 HintThe inputs are enabled and data39). Which of the following latch is used to design a gated D latch? Jk D Gated SR Latch T HintThe inputs of this latch is SET & RESET40). Which of the following latch is similar to the JK latch? D SR T Gated SR HintIn this latch, there is no o/p feedback to the inputs41). Which of the following latch can be formed by shortening the inputs of the JK latch? SR T D Gated SR HintThis is also called toggle latch42). When the T latch output will toggle? When the input is high Low Infinite None of the above HintWhen the input of the T latch is 143). How many types of latches are there in digital electronics? 2 4 6 8 HintThey are D, SR, Gated SR, Gated D, T, and JK44). Why is latch is called a bistable multivibrator? It includes two stable states Its working is similar to multivibrator It is a combinational circuit It removes the stored data HintThe two stable states are Low and High45). In digital electronics systems, the basic building blocks are? Flip flops & Latches Logic Gates Integrated Circuits Multiplexers HintThese circuits includes two stable states which are used to store the data46). The example of a bistable multivibrator is….? Latch Flip Flop Integrated Circuits Logic Gate HintBoth the latch and bistable multivibrator includes two stable states.47). Flip flops & latches are the basic building blocks of……? Encoders Sequential Circuits Integrated Circuits Decoders HintThe output of these circuits depends on the input timing48). Latches can be designed by using….? Encoders Logic Gates ICs Multiplexers HintA physical electronic device that is used to implement a Boolean function.49). Latches are used to built…? Flip Flops Logic Gates Encoders Decoders HintIt is used to store a 1-bit data50). Logic gates can be built with…? Flip Flops Transistors Encoders Multiplexers HintA semiconductor device is used to switch/amplify electronic signals Please refer to this link to know more about Logic GatesMCQs on Latches for Exams51). Which of the following has positive feedback…..? Transistors Encoders Latch Multiplexers HintIt is mainly used to store state data52). Which of the following doesn’t include a latch? Memory CLK signal Logic Gates Enable HintThis can be generated through a CLK generator53). How can we design a circuit without using logic gates and that are not combinational? Using Feedback Oscillator Inverter None HintBy creating loops within the circuit54). If the feedback in the circuit is positive then it tends to include…? Signals Stable States Enable Pin Inverter HintA latch includes high output & low output55). The feedback loop which is formed in a latch by an inverter is always…..? Negative Infinite Positive Always Changing HintIt exacerbates the results of a small trouble56). Which of the following is a popular microprocessor chip? 74LS337 74LS373 74LS278 74LS120 HintIt is an octal latch chip Please refer to this link to know more about Microprocessor57). A switch debouncing can be possible by using a…….? Integrator SR Latch D Flip Flop Multiplexer HintIt is an asynchronous device58). Which of the following is cross-coupled to make an SR latch with an active high i/p? 2 AND gates 2 OR Gates 2 NOR Gates 2 NOT Gates HintThe o/p of this gate is positive when two inputs are negative59). Which of the following statement is correct? A FF is edge-triggered A FF is level triggered A latch is not level triggered A latch edge-triggered HintFF is an alteration to the latch60). Which of the following is one of the drawbacks of a latch Chance of metastability Expensive Sensitive Has many stable states HintWhenever a latch is level-sensitive then it is caused 61). As compared to FFs, the latch design is ….? Hard Very flexible Not easy Complicated HintLatch design in digital electronics is easy62). Latch occupies very less area because of….? Its size is small Nano Design It uses fewer flip flops to design None of the above HintIts shape is very small63). In high-speed circuit design, the latch performance is….? Very quick Slow Medium Very slow HintLatches are asynchronous within the design of high-speed circuits64). Which of the following is the main benefit of a latch? Latches use fewer components Very speed operation Uses more logic gates It borrows required time to complete the circuit design if the design is not completed in time HintIf the circuit design is not finished in the set time they take time from others65). In which of the following, the circuit analyzing is difficult? Latches Flip Flops Multiplexers Demultiplexers HintBecause latches have level-sensitive property66). The testing of the latch circuit can be done by using…..? Multimeter Additional CAD program Simmulation Voltmeter HintIt uses an extra CAD program to test the circuit67). In asynchronous systems, which of the following latch is used? T Latch D Latch SR Latch JK Latch HintThese latches are used as input and output ports68). In synchronous 2-phase systems, which latches are used? SR Latch D Latch T Latch JK Latch HintFor decreasing the transit count these latches are used69). Single bit storage elements are called? Flip Flops Latches Logic Gates Encoders HintThese are used to store the data and computing70). Which of the following latch is similar to RS? D Latch T Latch JK latch Gated SR Latch HintIn RS latch, the o/p feedback is not present71). Which of the following latch is modified to form a gated D-latch? T Latch D Latch SR latch Gated SR Latch HintIn this latch, the R input should be changed to an inverted S72). When the JK latch inputs are shorted then which of the below latch is formed? T Latch SR latch D Latch Gated SR Latch HintWhen the input of this latch is high then the output will be toggled73). Why latches don’t work as a register? Lack of a CLK Signal Memory Binary Inputs Outputs HintLatches doesn’t include a CLK signal74). Sequential circuits are available in ….types? 2 4 5 6 HintThey are synchronous and asynchronous75). In sequential circuits, which of the following element provides memory? Encoder Decoder Combinational Logic Circuit Flip Flop HintA memory device that stores a single data bitLatches MCQs for Quiz76). At the end of bits in a shift register has……neighbors? 2 4 6 8 HintShift register has two neighbors at the end of the bit77). SR latches are also known as…? D Flip Flops Direct Coupled RS FFs Multiplexers None of above HintIt has two inputs like SET/RESET78). How a NAND-based SR latch is changed into an SR latch? By arranging a D-latch at every i/p By arranging an inverter at every i/p Both an inverter & a latch at its i/p None of the above HintBy connecting a latch and an inverter at its input79). Which of the following circuits have quick operations? Flip Flops Combinational Circuits Latches Multiplexers HintIn these circuits, different logic gates can be used80). In SR latch based on NAND gate, when the S=R=1 then what is the condition of the latch? Outputs will be low Outputs will be high Reset No change HintThere is no change within the latch condition81). When SR Latch is designed with NAND gates then the circuit is called as….? Active low circuit Active high circuit Combinational circuit Logic circuit HintThis circuit activates through a -Ve level trigger82). Which of the following latch is known as transparent latch? D Latch SK Latch T Latch None of the above HintThis latch is known as a data latch83). Which of the following circuits is known as two-state devices? Sequential logic circuits Logic gate circuits Combinational logic circuits None of the above HintThese circuits use memory elements84). How many categories are there in sequential logic circuits? 1 3 5 7 HintThe categories are event, CLK and pulse driven85). Sequential circuits are signified with….? Infinite state machine Finite state machine Multiplexers Encoders HintIt is also called FSM86). The storage elements that function through levels of the signal are known as…? Flip Flops Multiplexers Encoders Latches HintThese are used to design asynchronous sequential circuit87). The output crossing in SR Latch is called as? Coupling Cross-coupling Interfacing None of the above HintThis circuit uses cross-coupling feedback88). The amount of power used by latches is…..? Less Huge Very high None of the above HintLatches works with very little power89). Latches are better than….? Multiplexers Flip flops Logic gates Encoders HintTo get the quick realizations, these are very better90). In digital electronics, memories are considered as…? Essential components Storage elements Detachable elements Protection devices HintMemory in digital electronics is a very essential component91). The working of latches mainly depends on…? Enable i/p function Based on inputs Based on Memory Based on Logic Function HintIt depends on the function of enable input Please refer to this link to know more about Digital Electronics MCQs92). Transparent latches are used in….? Synchronous systems Asynchronous systems Digital systems Control systems HintThese systems are quite opposite to synchronous93). Which of the following IC is a quadruple transparent latch? 74HC76 74HC75 73HC20 75HC40 HintThese ICs are manufactured by Texas instruments94). The series of 74HC75 latch is? 7400 series 74 series 74H series 7H series HintThese are digital logic ICS95). The first electronic FF was invented by….? William George William Jouls William Eccles Lindley HintHe is the British physicists 96). The electronic FF was invented in which year? 1920 1910 1928 1918 HintIt was invented by two scientists namely William Eccles & F. W. Jordan97). In which of the following circuits, the o/p is mainly dependent on the present input? Combinational circuits Sequential circuits Logic circuits Multiplexers HintThese circuits don’t have a memory element98). In which of the following circuits, the o/p depend on the history of input? Sequential circuits Combinational circuits Logic circuits Multiplexers HintThese circuits have the least single memory element99). Which of the following device is a temporary storage device? Flip flop Logic gates Latch Multiplexers HintThese devices include two stable states100). What is the property of a latch? Level Sensing Memory Storage Voltage Detection Triggering HintBecause of this property, circuit analyzing is hard Time is Up! Time's up
