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    Discussion Question


    General Questions

    1).
    Any number with an exponent of zero is equal to:
    A   zero   
    B   one   
    C   that number   
    D   ten   
    ANS: B - one

    No answer description available for this question.

    2).
    In the decimal numbering system, what is the MSD?
    A   The middle digit of a stream of numbers   
    B   The digit to the right of the decimal point   
    C   The last digit on the right   
    D   The digit with the most weight   
    ANS: D - The digit with the most weight

    No answer description available for this question.

    3).
    Which of the following statements does NOT describe an advantage of digital technology?
    A   The values may vary over a continuous range.   
    B   The circuits are less affected by noise.   
    C   The operation can be programmed.   
    D   Information storage is easy.   
    ANS: A - The values may vary over a continuous range.

    No answer description available for this question.

    4).
    The generic array logic (GAL) device is ________.
    A   one-time programmable   
    B   reprogrammable   
    C   a CMOS device   
    D   reprogrammable and a CMOS device   
    ANS: B - reprogrammable

    No answer description available for this question.

    5).
    The range of voltages between VL(max) and VH(min) are ________.
    A   unknown   
    B   unnecessary   
    C   unacceptable   
    D   between 2 V and 5 V   
    ANS: C - unacceptable

    No answer description available for this question.

    6).
    What is a digital-to-analog converter?
    A   It takes the digital information from an audio CD and converts it to a usable form.   
    B   It allows the use of cheaper analog techniques, which are always simpler.   
    C   It stores digital data on a hard drive.   
    D   It converts direct current to alternating current.   
    ANS: A - It takes the digital information from an audio CD and converts it to a usable form.

    A DAC converts an abstract finite-precision number (usually a fixed-point binary number) into a concrete physical quantity (e.g., a voltage or a pressure).

    7).
    What are the symbols used to represent digits in the binary number system?
    A   0,1   
    B   0,1,2   
    C   0 through 8   
    D   1,2   
    ANS: A - 0,1

    No answer description available for this question.

    8).
    A full subtracter circuit requires ________.
    A   two inputs and two outputs   
    B   two inputs and three outputs   
    C   three inputs and one output   
    D   three inputs and two outputs   
    ANS: D - three inputs and two outputs

    No answer description available for this question.

    9).
    The output of an AND gate is LOW ________.
    A   all the time   
    B   when any input is LOW   
    C   when any input is HIGH   
    D   when all inputs are HIGH   
    ANS: B - when any input is LOW

    No answer description available for this question.

    10).
    Give the decimal value of binary 10010.
    A   610   
    B   910   
    C   1810   
    D   2010   
    ANS: C - 1810

    No answer description available for this question.

    11).
    Parallel format means that:
    A   each digital signal has its own conductor.   
    B   several digital signals are sent on each conductor.   
    C   both binary and hexadecimal can be used.   
    D   no clock is needed.   
    ANS: A - each digital signal has its own conductor.

    No answer description available for this question. 

    12).
    A decoder converts ________.
    A   noncoded information into coded form   
    B   coded information into noncoded form   
    C   HIGHs to LOWs   
    D   LOWs to HIGHs   
    ANS: B - coded information into noncoded form

    No answer description available for this question.

    13).
    A DAC changes ________.
    A   an analog signal into digital data   
    B   digital data into an analog signal   
    C   digital data into an amplified signal   
    D   none of the above   
    ANS: B - digital data into an analog signal

    No answer description available for this question.

    14).
    The output of a NOT gate is HIGH when ________.
    A   the input is LOW   
    B   the input is HIGH   
    C   the input changes from LOW to HIGH   
    D   voltage is removed from the gate   
    ANS: A - the input is LOW

    No answer description available for this question.

    15).
    The output of an OR gate is LOW when ________.
    A   all inputs are LOW   
    B   any input is LOW   
    C   any input is HIGH   
    D   all inputs are HIGH   
    ANS: A - all inputs are LOW

    No answer description available for this question.

    16).
    Which of the following is not an analog device?
    A   Thermocouple   
    B   Current flow in a circuit   
    C   Light switch   
    D   Audio microphone   
    ANS: C - Light switch

    No answer description available for this question.

    17).
    A demultiplexer has ________.
    A   one data input and a number of selection inputs, and they have several outputs   
    B   one input and one output   
    C   several inputs and several outputs   
    D   several inputs and one output   
    ANS: A - one data input and a number of selection inputs, and they have several outputs

    No answer description available for this question.

    18).
    A flip-flop has ________.
    A   one stable state   
    B   no stable states   
    C   two stable states   
    D   none of the above   
    ANS: C - two stable states

    No answer description available for this question.

    19).
    Digital signals transmitted on a single conductor (and a ground) must be transmitted in:
    A   slow speed.   
    B   parallel.   
    C   analog.   
    D   serial.   
    ANS: D - serial.

    No answer description available for this question. 

    20).
    In a certain digital waveform, the period is four times the pulse width. The duty cycle is ________.
    A   0%   
    B   25%   
    C   50%   
    D   100%   
    ANS: B - 25%

    No answer description available for this question.

    21).
    In positive logic, ________.
    A   a HIGH = 1, a LOW = 0   
    B   a LOW = 1, a HIGH = 0   
    C   only HIGHs are present   
    D   only LOWs are present   
    ANS: A - a HIGH = 1, a LOW = 0

    No answer description available for this question.

    22).
    Convert the fractional binary number 0000.1010 to decimal.
    A   0.625   
    B   0.50   
    C   0.55   
    D   0.10   
    ANS: A - 0.625

    No answer description available for this question.

    23).
    Digital representations of numerical values of quantities may BEST be described as having characteristics:
    A   that are difficult to interpret because they are continuously changing.   
    B   that vary constantly over a continuous range of values.   
    C   that vary in constant and direct proportion to the values they represent.   
    D   that vary in discrete steps in proportion to the values they represent.   
    ANS: D - that vary in discrete steps in proportion to the values they represent.

    No answer description available for this question.

    24).
    A common instrument used in troubleshooting a digital circuit is a(n) ________.
    A   logic probe   
    B   oscilloscope   
    C   pulser   
    D   all of the above   
    ANS: D - all of the above

    No answer description available for this question.

    25).
    The parallel transmission of digital data:
    A   is much slower than the serial transmission of data.   
    B   requires only one signal line between sender and receiver.   
    C   requires as many signal lines between sender and receiver as there are data bits.   
    D   is less expensive than the serial method of data transmission.   
    ANS: C - requires as many signal lines between sender and receiver as there are data bits.

    No answer description available for this question. 

    26).
    Convert the fractional decimal number 6.75 to binary.
    A   0111.1100   
    B   0110.1010   
    C   0110.1100   
    D   0110.0110   
    ANS: C - 0110.1100

    No answer description available for this question. 

    27).
    What is one relative disadvantage of serial transfer?
    A   It requires too many conductors.   
    B   Its interconnect system is complex.   
    C   It is slow.   
    D   It can only be used over very short distances.   
    ANS: C - It is slow.

    No answer description available for this question.

    28).
    Which format requires fewer conductors?
    A   Parallel   
    B   Serial   
    C   Both are the same   
    D   Cannot tell   
    ANS: B - Serial

    No answer description available for this question.

    29).
    A pulse has a period of 15 ms. Its frequency is ________.
    A   6.66 Hz   
    B   66.66 Hz   
    C   666.66 Hz   
    D   15 Hz   
    ANS: B - 66.66 Hz

    No answer description available for this question.

    30).
    Give the decimal value of binary 10000110.
    A   13410   
    B   14410   
    C   11010   
    D   12610   
    ANS: A - 13410

    No answer description available for this question.

    31).
    The rise time is the time it takes a pulse to go from ________.
    A   the base line to the maximum HIGH voltage   
    B   10% of the pulse amplitude to the maximum HIGH voltage   
    C   the base line to 90% of the pulse amplitude   
    D   10% of the pulse amplitude to 90% of the pulse amplitude   
    ANS: D - 10% of the pulse amplitude to 90% of the pulse amplitude

    No answer description available for this question.

    32).
    What is an analog-to-digital converter?
    A   It makes digital signals.   
    B   It takes analog signals and puts them in digital format.   
    C   It allows the use of digital signals in everyday life   
    D   It stores information on a CD.   
    ANS: B - It takes analog signals and puts them in digital format.

    No answer description available for this question

    33).
    A multiplexer has ________.
    A   one input and several outputs   
    B   one input and one output   
    C   several inputs and several outputs   
    D   several inputs and one output   
    ANS: D - several inputs and one output

    No answer description available for this question.

    34).
    What is the decimal value of 23 ?
    A   2   
    B   4   
    C   6   
    D   8   
    ANS: D - 8

    23 = 2*2*2=8

    35).
    An encoder converts ________.
    A   noncoded information into coded form   
    B   coded information into noncoded form   
    C   HIGHs to LOWs   
    D   LOWs to HIGHs   
    ANS: A - noncoded information into coded form

    No answer description available for this question.

    36).
    What kind of logic device or circuit is used to store information?
    A   Counter   
    B   Register   
    C   Inverter   
    D   Buffer   
    ANS: B - Register

    No answer description available for this question.

    37).
    PLCC packages have leads on ________.
    A   one side   
    B   two sides   
    C   three sides   
    D   four sides   
    ANS: D - four sides

    No answer description available for this question.

    38).
    What is the typical invalid voltage for a binary signal?
    A   0.7–2.8 volts   
    B   0.8–3 volts   
    C   0.8–2 volts   
    D   0.7–2.5 volts   
    ANS: C - 0.8–2 volts

    No answer description available for this question.

    39).
    Convert the fractional binary number 0001.0010 to decimal.
    A   1.40   
    B   1.125   
    C   1.20   
    D   1.80   
    ANS: B - 1.125

    No answer description available for this question. 

    40).
    Convert the fractional binary number 10010.0100 to decimal.
    A   24.50   
    B   18.25   
    C   18.40   
    D   16.25   
    ANS: B - 18.25

    No answer description available for this question. 

    41).
    How many binary bits are necessary to represent 748 different numbers?
    A   9   
    B   7   
    C   10   
    D   8   
    ANS: C - 10

    No answer description available for this question.

    42).
    A periodic digital waveform has a pulse width (tw) of 6 ms and a period (T) of 18 ms. The duty cycle is ________.
    A   3.3%   
    B   33.3%   
    C   6%   
    D   18%   
    ANS: B - 33.3%

    No answer description available for this question.

    43).
    Any number with an exponent of one is equal to:
    A   zero   
    B   one   
    C   two   
    D   that number   
    ANS: D - that number

    No answer description available for this question.

    44).
    Serial format means digital signals are:
    A   sent over many conductors simultaneously.   
    B   sent over one conductor sequentially.   
    C   sent in groups of eight signals.   
    D   sent in binary coded decimal.   
    ANS: B - sent over one conductor sequentially.

    No answer description available for this question.

    45).
    What is the decimal value of 2–1 ?
    A   0.5   
    B   0.25   
    C   0.05   
    D   0.1   
    ANS: A - 0.5

    No answer description available for this question.

    46).
    Which format can send several bits of information faster?
    A   Parallel   
    B   Serial   
    C   Both are the same   
    D   Cannot tell   
    ANS: A - Parallel

    No answer description available for this question. 

    47).
    The frequency of a pulse train is 2 kHz. The pulse period is ________.
    A   5 ms   
    B   50 ms   
    C   500 s   
    D   2 s   
    ANS: C - 500 s

    No answer description available for this question

    48).
    What has happened to the advances in digital technologies over the past three decades?
    A   Slowed down considerably   
    B   Continued to increase, but at a decreasing rate   
    C   Made excellent progress   
    D   Nothing short of phenomenal   
    ANS: D - Nothing short of phenomenal

    No answer description available for this question.

    49).
    A type of digital circuit technology that uses bipolar junction transistors is ________.
    A   TTL   
    B   CMOS   
    C   LSI   
    D   NMOS   
    ANS: A - TTL

    No answer description available for this question.

    50).
    How many unique symbols are used in the decimal number system?
    A   One   
    B   Nine   
    C   Ten   
    D   Unlimited   
    ANS: C - Ten

    No answer description available for this question.

    51).
    A classification of ICs with complexities of 12 to 100 equivalent gates on a chip is known as ________.
    A   SSI   
    B   MSI   
    C   LSI   
    D   VLSI   
    ANS: B - MSI

    No answer description available for this question.

    52).
    Which of the following is a semiconductor memory?
    A   RAM   
    B   MAR   
    C   CD-ROM   
    D   CD   
    ANS: A - RAM

    No answer description available for this question.

    53).
    The holes through a PC board are ________.
    A   smaller with SMT than with through-hole mounting   
    B   larger with SMT than with through-hole mounting   
    C   the same size as with through-hole mounting   
    D   usually unnecessary   
    ANS: C - the same size as with through-hole mounting

    No answer description available for this question

    54).
    A classification of ICs with complexities of 100 to 10,000 equivalent gates per chip is known as ________.
    A   SSI   
    B   MSI   
    C   LSI   
    D   VLSI   
    ANS: C - LSI

    No answer description available for this question.