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Syllabus

NEC Electronics · Practice

Chapters & sets

1. Basic Electrical and Electronics Engineering

Basic Electrical

Set 1106

Basic Electronics

Set 171 Set 233

2. Digital Logic and Microprocessor

Digital Logic

Set 150 Set 250 Set 350 Set 450 Set 550 Set 650 Set 749 Set 851 Set 950 Set 1050 Set 1150 Set 1232

Microprocessor

Set 150 Set 250 Set 350 Set 445 Set 550 Set 650 Set 720 Set 850 Set 969

3. Programming Language and Its Applications

Mixed chapter MCQs

Set 150 Set 249 Set 349 Set 451 Set 540

4. Computer Organization and Embedded Systems

Mixed chapter MCQs

Set 150 Set 249 Set 350 Set 450 Set 550 Set 650 Set 750 Set 849 Set 950 Set 1050 Set 1150

5. Computer Networks and Network Security

Basic Networking

Set 150 Set 253

Advanced Networking

Set 150 Set 250 Set 350 Set 450 Set 550 Set 655

10. Project Planning, Design and Implementation

Digital Logic Set 9

50 questions

Question 1

A 32-bit data word consists of

A.
2 bytes
B.
4 bytes
C.
4 nibbles
D.
3 bytes and 1 nibble

Question 2

Data are stored in a random-access memory (RAM) during the

A.
Read operation
B.
Write operation
C.
Enable operation
D.
Addressing operation

Question 3

Data that are stored at a given address in a random-access memory (RAM) is lost when

A.
Power goes off
B.
New data are written at the address
C.
The data are read from the address
D.
Answer (A) and (B)

Question 4

A ROM is a

A.
Nonvolatile memory
B.
Read/write memory
C.
Volatile memory
D.
Byte-organized memory

Question 5

A memory with 256 addresses has

A.
256 address lines
B.
A address lines
C.
A address lines
D.
8 address lines

Question 6

A byte-organized memory has

A.
1 data output
B.
8 data output
C.
4 data output
D.
16 data output

Question 7

The storage cell in a SRAM is

A.
A flip-flop
B.
A fuse
C.
A capacitor
D.
A magnetic domain

Question 8

A DRAM must be

A.
Replaced periodically
B.
Always enabled
C.
Refreshed periodically
D.
Programmed before each use

Question 9

A flash memory is

A.
Nonvolatile
B.
A read/write memory
C.
A read-only memory
D.
Answers (A) and (B)

Question 10

Hard disk, floppy disk, Zip disk, and Jaz disk are all

A.
Magneto-optical storage devices
B.
Magnetic storage devices
C.
Semiconductor storage devices
D.
Optical storage devices

Question 11

Optical storage devices employ

A.
Ultraviolet light
B.
Optical couplers
C.
Electromagnetic field
D.
Lasers

Question 12

A fixed-function IC package containing four AND gates in an example of

A.
MSI
B.
SOIC
C.
SMT
D.
SSI

Question 13

An LSI device has a circuit complexity of

A.
12 to 99 equivalent gates
B.
2000 to 5000 equivalent gates
C.
100 to 9999 equivalent gates
D.
10,000 to 99,999 equivalent gates

Question 14

A positive-going pulse is applied to an inverter. The time interval from the leading edge of the input to the leading edge of the output is 7 ns. This parameter is

A.
Speed-power product
B.
Propagation delay $t(_{PLH})$
C.
Propagation delay, $t(_{PLH})$
D.
Pulse width

Question 15

The CMOS family with the fastest switching speed is

A.
AC
B.
ACT
C.
HC
D.
ALVC

Question 16

If power were the major criterion in the design of a digital system, the logic family that you would probably use is

A.
HCL
B.
LV
C.
ALVC
D.
LVC

Question 17

When the frequency of the input signal to a CMOS gate is increased, the average power dissipation

A.
Decreases
B.
Does not change
C.
Increases
D.
Decreases exponentially

Question 18

CMOS operates more reliably than TTL in a high-noise environment because of its

A.
Lower noise margin
B.
Higher noise margin
C.
Input capacitance
D.
Smaller power dissipation

Question 19

Proper handling of a CMOS device is necessary because of its

A.
Fragile construction
B.
High-noise immunity
C.
Susceptibility to electrostatic discharge
D.
Low power dissipation

Question 20

Which of the following is not a TTL circuit?

A.
74F00
B.
74HC00
C.
74AS00
D.
74ALS00

Question 21

An open TTL NOR gate input

A.
Acts as a LOW
B.
Should be grounded
C.
Acts as a HIGH
D.
Answers (B) and (C)

Question 22

An LS TTL gate can drive a maximum of

A.
20 unit loads
B.
40 unit loads
C.
10 unit loads
D.
Unlimited unit loads

Question 23

If two unused inputs of a LS TTL gate are connected to an input being driven by another LS TTL gate, the total number of remaining unit loads that can be driven by this gate is

A.
Seven
B.
Seventeen
C.
Eight
D.
Unlimited

Question 24

The main advantage of ECL over TTL or CMOS is

A.
ECL is less expensive
B.
ECL consumes less power
C.
ECL is available in a greater variety of circuit type
D.
ECL is faster

Question 25

ECL cannot be used in

A.
High-noise environments
B.
High-frequency applications
C.
Damp environments
D.
ECL is less expensive

Question 26

The basic mechanism for storing a data bit in an

E(^2)

CMOS cell is

A.
Control gate
B.
Floating gate
C.
Floating drain
D.
Cell current

Question 27

A CPLD is a

A.
CMOS programmable logic device
B.
Capacitive programmable logic device
C.
Complex programmable logic device
D.
Complementary process latching device

Question 28

VHDL is a

A.
Logic device
B.
Computer language
C.
PLD programming language
D.
Very high density logic

Question 29

The types of SPLDs do not include

A.
GAL
B.
RAM
C.
PROM
D.
PAL

Question 30

A GAL has

A.
A reprogrammable AND array, a fixed OR array, and programmable output logic
B.
A fixed AND array and a programmable OR array
C.
One-time programmable AND and OR array
D.
Reprogrammable AND and OR array

Question 31

An SPLD that has a programmable AND array and a fixed OR array is a

A.
PROM
B.
PAL
C.
PLA
D.
GAL

Question 32

A connection between a row and column in a PAL array is made by

A.
Blowing a fusible link
B.
Leaving a fusible link intact
C.
Connecting an input variable to the input line
D.
Connecting an input variable to the product tem line

Question 33

The device number PAL14H4 indicates

A.
A PAL with fourteen active-HIGH outputs and four inputs
B.
A PAL that implements fourteen AND gates and four OR gates
C.
A PAL with implements and four active-HIGH outputs
D.
Who the manufacturer is

Question 34

A GAL is different from a PAL because

A.
A GAL has more inputs and outputs
B.
A GAL is implemented with a different technology
C.
A GAL can replace several different PALs
D.
All except answer 1

Question 35

The reprogrammable cells in a GAL array are

A.
TTL
B.
ECL
C.
E $^2$ CMOS
D.
Bipolar fuses

Question 36

OLMC is an acronym for

A.
Output Logic Main Cell
B.
Output Logic Macrocell
C.
Optimum Logic Multiple Channel
D.
Odd-parity Logic Master Check

Question 37

Two ways in which a GAL output can be configured are

A.
Combinational and I/O
B.
Fixed and variable
C.
Simple and complex
D.
Combinational and registered

Question 38

The device number GAL22V10 means that

A.
The device has22 dedicated inputs and 10 dedicated outputs
B.
The device has 22 inputs including dedicated inputs and I/Os and 10 outputs either dedicated or I/Os
C.
The device has a variable number of inputs form a maximum of 22 to a minimum of 10
D.
The device has 24 inputs including dedicated inputs and I/Os and 14 outputs either dedicated or I/Os

Question 39

To conventionally program an SPLD, you need a

A.
Special fixture
B.
Special fixture and a master PLD that has been preprogrammed at the factory
C.
Computer, a programmer, and HDL software
D.
Computer, a programmer, and BASIC software

Question 40

ISP stands for

A.
In-System Programmable
B.
Integrated Silicon Program
C.
Integrated System Program
D.
In-System Integrated Programming

Question 41

The GAL22V10 has

A.
10 inputs and 22outputs
B.
22 dedicated inputs and 10 outputs
C.
12 dedicated inputs and 10 dedicated outputs
D.
12 dedicated inputs and 10 outputs, any of which can be an input

Question 42

The GAL22V10 operates on a dc supply voltage of

A.
5V
B.
3.3V
C.
10V
D.
1.2V

Question 43

OLMC stand for

A.
Output logic modular circuit
B.
Output latch memory cell
C.
Output logic macrocell
D.
Overall logic matrix circuit

Question 44

The three states of a tri-state output buffer are

A.
HIGH, LOW, high impedance
B.
HIGH, LOW, in between
C.
HIGH, LOW, ground
D.
Right, left, centre

Question 45

The OLMC of the GAL22V10 contains

A.
One OR gate, one flip-flop, two multiplexers
B.
One OR gate, one flip-flop, one multiplexer
C.
One AND gate, one latch, two multiplexers
D.
One OR gate, one flip-flop, two decoders

Question 46

The GAL16V8 has

A.
16 dedicated inputs and 8 outputs
B.
8 dedicated inputs and 8 inputs /outputs
C.
8 inputs and 16 outputs
D.
16 input/outputs and 8 outputs

Question 47

A typical OLMC consists of

A.
Gates, multiplexers, and a flip-flop
B.
Gates, and a shift register
C.
A Gray code counter
D.
A fixed logic array

Question 48

A CPLD is a

A.
CMOS PLD
B.
Complementary PLD
C.
Complex PLD
D.
A fixed logic array

Question 49

A CPLD contains

A.
Shift registers
B.
Logic arrays
C.
Programmable interconnections
D.
Answers (B) and (C)

Question 50

FPGA stands for

A.
Fast propagation gate array
B.
Field programmable gate array
C.
Field presentable gate application
D.
File programmable gate array

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