Explore topic-wise MCQs in Digital Electronics.

This section includes 289 Mcqs, each offering curated multiple-choice questions to sharpen your Digital Electronics knowledge and support exam preparation. Choose a topic below to get started.

101.

What will be the starting address of memory chip, given that memory address of last location of an 1K byte memory chip is FBFFH?

A. F800 H
B. FA00H
C. EB00H
D. EBFFH
Answer» B. FA00H
102.

The number of chips required to make up 1K-bytes of memory, if the available chip size is 256 1 bits

A. 4
B. 8
C. 16
D. 32
Answer» E.
103.

The number of chips required to make up 16 K-bytes memory, if the available memory chip size is 2048 8 bits

A. 4
B. 8
C. 16
D. 32
Answer» C. 16
104.

The architecture of a PLA device differs from that of a PROM device in the following

A. The former has a fixed OR array while the latter has a programmable OR array
B. The former has a programmable AND array while the latter has a hard-wired AND array.
C. The former has larger number of AND gates in the AND array than the latter for a given number of variables.
D. The latter has a fixed OR array while the former has a programmable OR array.
Answer» B. The former has a programmable AND array while the latter has a hard-wired AND array.
105.

A ROM is usually not preferred to implement those Boolean functions which

A. Are very complex
B. Can otherwise the implemented using a PLA
C. Have a large number of don t care conditions
D. Have large number of outputs
Answer» C. Have a large number of don t care conditions
106.

It is desired to implement a binary multiplier capable of multiplying two 3-bit binary numbers. Size of ROM would be

A. 64 4
B. 1024 6
C. 64 8
D. 128 6
Answer» E.
107.

A masked programmed version of PAL device that is pin compatible to its PAL counterpart is known as

A. PLA device
B. PAL device
C. PLS device
D. PGA device
Answer» D. PGA device
108.

A programmable array logic (PAL) device has a

A. Programmable AND-array at the input and a fixed OR-array at the output
B. Fixed AND-array at the input and a programmable OR-array at the output
C. Fixed AND-array at the input and a fixed OR-array at the output
D. None of these
Answer» C. Fixed AND-array at the input and a fixed OR-array at the output
109.

A PAL device is marked PAL-1618. It implies the following

A. It has sixteen active-LOW inputs
B. It has eight active-LOW outputs
C. It has sixteen inputs and eight active-LOW outputs
D. It has eight inputs and sixteen active-LOW outputs
Answer» B. It has eight active-LOW outputs
110.

A PLA-like architecture that can implement a full adder should at least have

A. Eight 6-input programmable AND gate, two 8-input programmable OR gates
B. Seven 6-input programmable AND gates, two 4-input programmable OR Gates
C. Eight 6-input programmable AND gates, two 4-input programmable OR gates
D. Sixteen 3-input programmable AND gates, two 8- input programmable OR gates
Answer» E.
111.

Size of the ROM required to implement a 16-to-1 multiplexer would be

A. 512K 2
B. 1M 1
C. 1M 2
D. 256 2
Answer» D. 256 2
112.

A PROM device that can generate any eight desired four-variable Boolean functions will have

A. Four-2-inputs AND gates in the AND array and eight 8-input OR gates in the OR array.
B. Eight 2-input AND gates in the AND array and eight 16 input OR gates in the OR array.
C. Sixteen 2-inputs AND gates in the AND array and eight 16-input OR gates in the OR array.
D. Sixteen 8-input AND gates in the AND array and eight 16-input OR gates in the OR array.
Answer» E.
113.

Identify the programmable interconnect technology used in PLDs

A. Antifuse
B. Fuse
C. Static RMA controlled switches
D. All of these
Answer» E.
114.

The most widely used hardware description language for describing digital designs on CPLD and FPGA devices is

A. VHDL
B. JAVA-HDL
C. Verilog
D. ABEL
Answer» B. JAVA-HDL
115.

A programmable interconnect device that has high initial resistance and can be permanently programmed to highly conducting path is known as

A. Fuse
B. Floating-gate transistor
C. Anti-fuse
D. PGA device
Answer» C. Anti-fuse
116.

Memory devices are used for

A. Temporary storage of data
B. Semi-permanent storage of data
C. Permanent storage of data
D. All of these
Answer» C. Permanent storage of data
117.

Which one of the following types of RAM needs periodic refreshing

A. Asynchronous SRAM
B. DRAM
C. Synchronous SRAM
D. All types of RAM need periodic refreshing
Answer» D. All types of RAM need periodic refreshing
118.

Three main building blocks of RAM are

A. Array of memory cells, address decoder and read/write control logic
B. Array of memory cells, input buffers and output buffers
C. Array of memory cells, address decoder and buffers
D. Address decoder, address encoder and memory cells
Answer» E.
119.

Identify the primary memory device

A. Registers built into the CPU
B. RAM and ROM
C. Cache memory
D. All of these
Answer» C. Cache memory
120.

A 16K RAM chip can stores

A. 64000 bytes
B. 65536 bytes
C. 65536 bits
D. 64000 bits
Answer» E.
121.

Identify the characteristic feature or features of random access memory

A. It is a serial access memory
B. Data can be read from or written into any of the memory locations regardless order in which they are arranged
C. All memory locations can be accessed with the same speed
D. Both (B) and (C)
Answer» E.
122.

With reference to erasable PROM devices, identify the true statement

A. In the case of EEPROM selective erasure is not possible
B. UV EPROM erasure process is very fast
C. In the case of UV EPROM, selective erasure is not possible
D. EEPROM has relatively much higher density as compared to UV EPROM.
Answer» D. EEPROM has relatively much higher density as compared to UV EPROM.
123.

In volatile storage, data is lost

A. Gradually with time
B. As soon as saturation point is crossed
C. As soon as programme is over
D. When power is removed
Answer» E.
124.

Memory that requires refreshing cycle is

A. Dynamic MOS
B. RAM
C. ROM
D. All of these
Answer» B. RAM
125.

One of the following is true with respect to CPLD and FPGA devices

A. CPLD architecture offers greater flexibility
B. FPGA devices have very complex configurable logic blocks
C. CPLD devices offer relatively lower flexibility but more predictable timing characteristics
D. FPGA devices offer relatively lower flexibility but more predictable timing characteristics
Answer» C. CPLD devices offer relatively lower flexibility but more predictable timing characteristics
126.

The primary memory of a computer system

A. Holds the instructions of the program to be executed
B. Stores data to be processed
C. Stores the intermediate results of any calculation during processing of data
D. All of these
Answer» B. Stores data to be processed
127.

Which of the following is a permanent memory?

A. RAM only
B. ROM only
C. Both RAM and ROM
D. Neither RAM nor ROM
Answer» C. Both RAM and ROM
128.

A temporary memory is

A. Destroyed in few milliseconds
B. Destroyed in few seconds
C. Destroyed in few minutes
D. Destroyed when power is switched off.
Answer» E.
129.

Which of the following is a temporary memory?

A. RAM only
B. ROM only
C. Both RAM and ROM
D. Neither RAM nor ROM
Answer» B. ROM only
130.

The abbreviation TTL stands for

A. Transmitter transistor load
B. Tuned transistor loop
C. Transistor-transistor logic
D. Transistor-transformer logic
Answer» D. Transistor-transformer logic
131.

A Schmitt trigger

A. Is a digital circuit that produces sinusoidal output regardless of the input waveform
B. Is a digital circuit that produces rectangular output regardless of the input waveform
C. Is a digital circuit that produces a trapezoidal output regardless of the input.
D. None of these
Answer» C. Is a digital circuit that produces a trapezoidal output regardless of the input.
132.

Indicate the false statement. The SWR on a transmission line if infinity the line is terminated in

A. A short circuit
B. A complex impedance
C. An open circuit
D. A pure reactance
Answer» C. An open circuit
133.

With reference of a 2K bit ROM organized as 256 8 array of memory cells, which one of the following is true

A. It uses 2000 memory cells
B. It uses 256 rows of eight memory cells each
C. It uses 2048 memory cells and 8 line to 256-line address decoder
D. Both (B) and (C) are true
Answer» B. It uses 256 rows of eight memory cells each
134.

The basic memory cell in a DRAM is a

A. Capacitor
B. MOS switch and a capacitor
C. MOSFET
D. Flip-flop
Answer» B. MOS switch and a capacitor
135.

Resistor free logic

A. TTL
B. CMOS
C. 4ns ECL
D. 8ns ECL
Answer» C. 4ns ECL
136.

SRAM devices are made using

A. Bipolar, MOS or BICMOS technologies
B. Bipolar technology
C. MOS technology
D. BICMOS technology
Answer» D. BICMOS technology
137.

Logic with lowest power dissipation per gate is

A. TTL
B. CMOS
C. 4ns ECL
D. 8ns ECL
Answer» C. 4ns ECL
138.

Logic with fan out of more than 50 is

A. CMOS
B. TTL
C. 4ns ECL
D. 8ns ECL
Answer» B. TTL
139.

Fastest logic

A. TTL
B. LSI
C. CMOS
D. ECL
Answer» E.
140.

Current-mode logic (CML) is the same as

A. LSI
B. CMOS
C. TTL
D. ECL
Answer» E.
141.

The total number of inhibit drivers required for a 16K, 24- bit/word memory with a 3-D organization is

A. 4
B. 8
C. 16
D. 24
Answer» E.
142.

For a 16K, 32-bit memory, the size of MBR register is

A. 4
B. 16
C. 32
D. 64
Answer» D. 64
143.

A microprocessor consists of a small number of LSI chips containing

A. Control unit
B. Logic unit
C. Arithmetic unit
D. All of the above
Answer» E.
144.

A flip-flop free from race problem is

A. JK flip-flop
B. D flip-flop
C. T flip-flop
D. Master-slave flip-flop
Answer» E.
145.

Which of the following ICs allow wired AND connections

A. 7440
B. 8080
C. 7990
D. 7410
Answer» B. 8080
146.

Which of the following name is associated with microprocessor manufacturer?

A. Fairchild
B. IBM
C. Motorola
D. Intel
Answer» E.
147.

Intel 8080 has

A. 16 pins
B. 24 pins
C. 32 pins
D. 40 pins
Answer» E.
148.

The unit of the speed of a digital IC is

A. Hz
B. kHz
C. MHz
D. GHz
Answer» D. GHz
149.

Identify the IC with only one NAND gate?

A. 7400
B. 7410
C. 7420
D. 7430
Answer» E.
150.

What is the minimum number of flip-flops required in a counter to count 60 pulses?

A. 2
B. 4
C. 6
D. 8
Answer» D. 8