Digital Circuits Question & AnswersJanuary 17, 2022 By WatElectronics This article lists 100 Digital Circuits MCQs for Engineering Students. All the Digital Circuits Questions & Answers given below includes solution and link wherever possible to the relevant topic.In digital circuits, the input and output will be in digital format. The circuits will have basic gates, multiplexers, counters, registers, and microprocessors. The three types of electronic circuits are digital circuits, analog circuits, and mixed-signal circuits. In integrated circuits manufacture, most of the designs that we have are digital in nature. The digital signals are stable, less prone to noise, use less power, and are not affected during data transmission.1). Which one of the following has smaller integrated circuits? Analog electronics Digital electronics Both a and b None of the above HintThe integrated circuits are not smaller in analog electronics compared to digital electronics2). Which one of the following occupies a lesser area? Analog electronics Digital electronics Both a and b None of the above HintDigital electronics occupies lesser area compare to analog electronics3). The levels of integration is categorized into ______________ types? One Two Three Four HintThe levels of integration are categorized into four types they are SSI, LSI, VLSI, and MSI4). The combinational logic circuits and sequential circuits are type of _____________ circuits? Analog Digital Both a and b None of the above HintThe combinational logic circuits and sequential circuits are a type of digital circuits5). In _____________ logic circuit, the output depends only on present input? Combinational Sequential Both a and b None of the above HintIn the combinational logic circuit, the output depends only on the present input6). _______________ gates are required to build a half adder? EX-OR AND NOR None of the above HintThe EX-OR gates are required to build a half adder7). Which one of the following is not a universal gate? EX-NOR NAND NOR None of the above HintThe EX-NOR is not a universal gate8). How many inputs does a full adder logic circuit will have? One Two Three Four HintThe full adder logic circuits will have three inputs9). What are the advantages of a digital system over an analog system? Ease of programmability Reduction in cost of hardware High speed and reliability All of the above HintThe advantages of a digital system over the analog system are ease of programmability, reduction in the cost of hardware, high speed and reliability10). What are the advantages of static RAM? High-speed High power consumption Low density and capacity All of the above HintThe advantages of static RAM are high speed, high power consumption, low density, and capacity11). The analog to digital conversions fall into _____________ general type of technique? One Two Three Four HintThe analog to digital conversions fall into three general types of technique they are parallel encoding, successive approx., and single or double slope12). In _____________ digital circuit, the output depends on present state and present input of the circuit? Combinational Sequential Both a and b None of the above Hint- In a sequential digital circuit, the output depends on the present state and present input of the circuit Read more about Digital Circuits13). How many outputs do full adder logic circuits will have? One Two Three Four HintThe full adder logic circuits will have two outputs14). If the two inputs are 00 then the OR gate output will be ________ High Low Moderate Constant HintIf the two inputs are 00 then the OR gate output will be high15). The level-sensitive (latches) are categorized into ______________ types? One Two Three Four HintThe level-sensitive (latches) are categorized into two types they are high level sensitive and low level sensitive16). The edge-triggered (flip flops) are categorized into _______________ types? One Two Three Four HintThe edge-triggered (flip flops) are categorized into two types they are rising edge-triggered and falling edge triggered17). The sequential circuit elements are categorized into ____________ types? One Two Three Four HintThe sequential circuit elements are categorized into two types they are level sensitive and edge triggered18). The one’s compliment of 11001011 is ________________ 00110101 0011010 00110000 00110100 HintThe one’s compliment of 11001011 is 0011010119). The two’s compliment of 11001011 is ______________ 11110101 00110101 00110000 00110100 HintThe two’s compliment of 11001011 is 0011010120). The addition of +43 and +19 results as _____________ in two’s compliment? 11110101 00110101 00110000 0111110 HintThe addition of +43 and +19 results as 0111110 in two’s compliment21). Which one of the following complements is used for arithmetic operations? 1’s compliment 10’s compliment 2’s compliment 9’s compliment HintFor arithmetic operations, only two’s complement is used22). Which one of the following complements is used for logical manipulations? 1’s compliment 10’s compliment 2’s compliment 9’s compliment HintThe one’s complement is used for logical manipulations23). How many operations are required for one’s compliment? One Two Three Four HintOnly one operation is required for one’s compliment24). How many arithmetic operations are required for two’s complement? One Two Three Four HintThe arithmetic operations are required for two’s complement is one25). The logic circuitry is used to detect the _______________ Overflow and underflow Only overflow MSD, LSD All of the above HintThe logic circuitry is used to detect only overflowDigital Circuit Important Questions for Interviews26). An overflow is a ____________ problem and it occurs in ____________ position? Software, MSD Hardware, LSD Software, Middle None of the above HintAn overflow is a software problem and it occurs in the MSD position27). The OR operation is performed by _____________ properties in a Boolean algebra? Associative Distributive Commutative All of the above HintThe OR operation is performed by associative, distributive, and commutative properties in a boolean algebra28). Which one of the following is an expression for absorption law? A+AB=A A+B=B+A A+AB=B None of the above HintThe A+AB=A is an expression for absorption law29). How many cells are there in a four-variable K-map? Four Six Sixteen Twenty HintIn a four-variable k-map there are sixteen cells30). The maximum clock frequency of advanced Schottky transistor-transistor logic (AS-TTL) is of ___________ 1MHz 10MHz 105MHz 3MHz HintThe maximum clock frequency of advanced Schottky transistor-transistor logic (AS-TTL) is of 105MHz31). The Schottky high speed transistor-transistor logic (S-TTL) is of ___________ 1MHz 100MHz 105MHz 3MHz HintThe Schottky high-speed transistor-transistor logic (S-TTL) is of 100MHz32). Which one of the following TTL (Transistor-Transistor Logic) has the shortest propagation delay? AS-TTL S-TTL HS-TTL None of the above HintThe advanced Schottky TTL (Transistor-Transistor Logic) has the shortest propagation delay33). What is the standard form of DLP? Dual in Long Packages Dual in Line Packages Double in Long Packages None of the above HintThe standard form of DLP is Dual in Line Packages34). What is the standard form of LCC? Long Chip Carrier Large Chip Carrier Leadless Chip Carrier None of the above HintThe standard form of LLC is Leadless Chip Carrier35). The fan-out and the fan-in both are characteristics of _____________ Logic families Registers Oscillators None of the above HintThe fan-out and the fan-in both are characteristics of logical families36). What is the standard form of DTL? Diode Transistor Logic Double Transistor Logic Direct Transistor Logic None of the above HintThe standard form of DTL is Diode Transistor Logic37). How many stages does diode transistor logic consists of? One Two Three Four HintThe diode transistor logic consists of three stages they are an output diode logic, an input diode logic, and an intermediate logic38). The Transistor-Transistor Logic is a _____________logic? Current sinking Voltage sinking Both a and b None of the above HintThe Transistor-Transistor Logic is a current-sinking logic39). What is the standard form of PGA? Plastic Grid Array Pen Grid Array Pin Grid Array None of the above HintThe standard form of PGA is Pin Grid Array40). What is the standard form of ECL? Emitter Collector Logic Emitter Capacitor Logic Emitter Coupled Logic None of the above HintThe standard form of ECL is Emitter Coupled Logic41). What is the standard form of CML? Capacitor Mode Logic Common Mode Logic Collector Mode Logic None of the above HintThe standard form of CML is Collector Mode Logic42). In an emitter-coupled logic the output is taken from _______________ Collector Base Emitter None of the above HintIn an emitter-coupled logic the output is taken from the collector43). What is the standard form of CMOS? Continuous Metal Oxide Semiconductor Complex Metal Oxide Semiconductor Complementary Metal Oxide Semiconductor None of the above HintThe standard form of CMOS is Complementary Metal Oxide Semiconductor44). In an emitter-coupled logic the fan-out capacity is ___________ High Low Very low Moderate HintIn an emitter-coupled logic the fan-out capacity is high45). What is the standard form of SCFL? Source Coupled Logic Source Common Logic Source Capacitor Logic None of the above HintThe standard form of SCFL is Source Coupled Logic46). In which year does emitter-coupled logic is invented? 1956 1980 1996 2000 HintIn 1956 the emitter-coupled logic is invented47). What is the standard form of CTDL? Complimented Transistor Diode Logic Complex Transistor Diode Logic Continuous Transistor Diode Logic None of the above HintThe standard form of CTDL is Complimented Transistor Diode Logic48). Who invented TTL (Transistor-Transistor Logic)? Chris Brown Frank Wanlass James L.Buie None of the above HintThe Transistor-Transistor Logic is invented by James L.Buie49). Who invented emitter-coupled logic (ECL)? Baker Clamp Frank Wanlass Hannon S.Yourke None of the above HintThe Hannon S.Yourke invented emitter-coupled logic (ECL)50). The emitter-coupled logic circuits usually operates with _____________ voltage? High Positive Negative Both b and c HintThe emitter-coupled logic circuits usually operates with positive voltageDigital Circuit Quiz Questions and Answers Read more about Digital Circuits51). What is the standard form of LVPECL? Low Voltage Positive Emitter Coupled Logic Line Voltage Positive Emitter Coupled Logic Low Voltage Positive Emitter Capacitor Logic None of the above HintThe standard form of LVPECL is Low Voltage Positive Emitter Coupled Logic52). What is the standard form of IIL? Integrated Integrated Logic Injection Integrated Logic Integrated Injection Logic None of the above HintThe standard form of IIL is Integrated Injection Logic53). The integrated injection logic also called as _____________ transistor logic? Merged Single Multiple None of the above HintThe integrated injection logic also called merged transistor logic54). What is the standard form of TCTL? Transistor-Capacitor-Transistor-Logic Transistor-Coupled-Transistor-Logic Transistor-Complementary-Transistor-Logic None of the above HintThe standard form of TCTL is Transistor-Coupled-Transistor-Logic55). The metal oxide semiconductor is being used in _____________ integration? Small scale Large scale Very large scale Both b and c HintThe metal oxide semiconductor is being used in large scale and very large scale integration56). What is the standard form of COS-MOS? Complementary Symmetry Metal Oxide Semiconductor Complex Symmetry Metal Oxide Semiconductor Common Symmetry Metal Oxide Semiconductor None of the above HintThe standard form of COS-MOS is Complementary Symmetry Metal Oxide Semiconductor57). The complementary metal-oxide-semiconductor technology is used in ___________ Microprocessor Digital logic Both a and b None of the above HintThe complementary metal-oxide-semiconductor technology is used in microprocessors as well as in digital logic58). The important characteristics of complementary metal-oxide-semiconductor is ___________ Has low static power consumption Has high noise immunity Both a and b None of the above HintThe important characteristics of the complementary metal-oxide-semiconductor are it has low static power consumption and high noise immunity59). The programmable read-only memories are available in _______________ technologies? MOSFET FET & MOSFET MOS & Bipolar None of the above HintThe programmable read-only memories are available in MOS and bipolar technologies60). What is the standard form of PSRAM? Pseudo Static Read Access Memory Pseudo Static Random Access Memory Pseudo Static Read Only Memory None of the above HintThe standard form of PSRAM is Pseudo Static Random Access Memory61). What is the standard form of PLD? Programmable Logic Devices Pseudo Logic Devices Positive Logic Devices None of the above HintThe standard form of PLD is Programmable Logic Devices62). The programmable logic devices contains large number of ____________ Gates Registers Flip-flops All of the above HintThe programmable logic devices contain a large number of gates, registers, and flip flops63). The programmable logic devices are categorized into ____________ types? One Two Three Four HintThe programmable logic devices are categorized into three types they are PROM, PAL, and PLA64). What is the standard form of PLA? Programmable Logic Array Programmable Local Array Programmable Load Array None of the above HintThe standard form of PLA is Programmable Logic Array65). The outputs of the AND gate in programmable logic devices is known as ______________ lines? Control b)c)d) Output Input None of the above HintThe outputs of the AND gate in programmable logic devices are known as control lines66). The programmable logic array is used to implement _______________ circuit? Sequential Combinational Complex combinational None of the above HintThe programmable logic array is used to implement complex combinational circuit67). What is the standard form of FPGA? Float Programmable Gate Array First Programmable Gate Array Field Programmable Gate Array None of the above HintThe standard form of FPGA is Field Programmable Gate Array68). The applications of programmable logic arrays are ______________ Configurable PALs Registered PALs PAL programming All of the above HintThe applications of programmable logic arrays are configurable PALs, registered PALs, and PAL programming69). What is the standard form of HDL? Higher Description Language Higher Description Logic Hardware Description Language None of the above HintThe standard form of HDL is Higher Description Language70). What is the standard form of PAL? Programmable Array Logic Programmable Array Local Programmable Array Load None of the above HintThe standard form of PAL is Programmable Array Logic71). How many decimals does the decimal counter have? One Ten Three Five HintThe decimal counter have ten decimals72). How many flip-flops are required in a four-bit up-down counter? One Ten Three Four HintThe four flip-flops are required in four-bit up-down counter73). What is the standard form of VHSIC? Very High Speed Integrated Circuit Very High-Speed Integrated Clock Variable High-Speed Integrated Circuit None of the above HintThe standard form of VHSIC is Very High-Speed Integrated Circuit74). What is the standard form of VHDL? Very High Definition Language Very High Description Language Verilog Hardware Definition Language None of the above HintThe standard form of VHDL is Verilog Hardware Definition Language 75). How many select lines are required in one to four demultiplexers? One Two Three Four HintThe two select lines are required in one to four demultiplexerDigital Circuit Interview Questions and Answers76). How many light-emitting diodes are used in a seven-segment display? One Two Seven Four HintThe seven light-emitting diodes are used in seven-segment display77). The random access memory is also called as ______________ memory? MAR RWM MBR None of the above HintThe random access memory is also called read-write memory78). Who invented one-transistor dynamic random access memory? Denard Kilby Noyce None of the above HintThe Denard invented one-transistor dynamic random access memory79). Who invented a solid-state rectifier? Denard Kilby Noyce Braun HintThe Braun invented solid-state rectifier in 1874 Read more about Rectifiers80). What is the standard form of EDA? Electronic Design Automation Electrical Design Automation Electronic Description Automation None of the above HintThe standard form of EDA is Electronic Design Automation81). Which one of the following is a part of electrical engineering? Analog electronics Digital electronics Power electronics None of the above HintThe power electronics is a part of electrical engineering82). Which one of the following works with two-state signals? Analog electronics Digital electronics Power electronics None of the above HintThe digital electronics work with two state signal83). Which one of the following works with extremely low current and low voltage? Analog electronics Digital electronics Power electronics Both a and b HintThe digital electronics work with extremely low current and low voltage84). Which one of the following works with high current and high voltage? Analog electronics Digital electronics Power electronics Both a and b HintThe power electronics work with high current and high voltage85). Which one of the following electronics mainly delays with analyzing, switching, mixing, multiplexing, and process of electronic signals? Analog electronics Digital electronics Power electronics Both a and b HintThe digital electronics mainly delays with analyzing, switching, mixing, multiplexing, and process of electronic signals86). Which one of the following electronics uses only active components? Analog electronics Digital electronics Power electronics Both a and b HintThe digital electronics use only active components87). Which one of the following electronics has very low noise and distortion? Analog electronics Digital electronics Power electronics Both a and b HintThe digital electronics have very low noise and distortion88). In which one of the following electronics there is no power loss? Analog electronics Digital electronics )Power electronics Both a and b HintIn digital electronics there is no power loss89). Which one of the following electronics helps to analyze the data of a system? Analog electronics Digital electronics Power electronics Both a and b HintThe digital electronics helps to analyze the data of a system90). In which one of the following electronics there is no electrical safety hazard? Analog electronics Digital electronics Power electronics Both a and b HintIn digital electronics there is no electrical safety hazard91). Which one of the following is an example of digital electronics? Digital clocks SMPS Radios None of the above HintThe digital clock is an example of digital electronics92). Which one of the following is not an example for digital electronics? Digital clocks Computers Smartphones UPS HintThe UPS is not an example of digital electronics93). Which one of the following signal stores in the form of binary bit? Analog Digital Both a and b None of the above HintThe digital signals stores in the form of binary bit94). The CDs, DVDs, computers are few examples of ___________ signal? Analog Digital Both a and b None of the above HintThe CDs, DVDs, computers are a few examples of digital signal95). What is the output for the below circuit? 1 0 A A+B HintThe output for the above circuit is one96). For the below circuit the input combination should be ___________, if the output F is 1 A=1, B=1, C=1 A=1, B=0, C=0 A=0, B=0, C=1 A=0, B=0, C=0 HintFor the below circuit the input combination should be A=0, B=0, C=1, if the output F is 197). Which one of the following is a correct Boolean expression for the below circuit? M1=(P XOR Q) XOR R M1=(P OR Q) XOR R M1=(P AND Q) XOR R M1=(P NAND Q) XOR R HintThe correct Boolean expression for the above circuit is M1=(P XOR Q) XOR R98). The output should be 1 if the inputs of the circuit A, B, C is equal to ______________ 0, 1, 1 1, 1, 1 0, 1, 0 0, 0, 1 HintThe output should be 1 if the inputs of the circuit A, B, C is equal to 0, 1, 199). The below logic diagram is a 4 bit ___________________ shift register? Serial in, parallel-out Serial in, serial-out, shift right, shift left Parallel in, serial-out Parallel in, parallel-out HintThe above logic diagram is a 4 bit serial-in, serial-out, shift right, shift left sift register100). The below logic diagram is a 4 bit ___________________ shift register? Serial in, parallel-out Serial in, serial-out, shift right, shift left Parallel in, serial-out Parallel in, parallel-out HintThe above logic diagram is a 4 bit serial-in, parallel-out shift register Time's up
