Q.1

When the analog input to a tracking A/D converter is at a constant level, the digital output will oscillate.

  • True
  • False
Q.2

One form of a sigma/delta modulator circuit is designed to convert a continuous analog signal into a modulated bit stream (A/D).

  • True
  • False
Q.3

What is the disadvantage to using a counter-ramp type ADC?

  • complex circuit
  • high cost
  • very slow
Q.4

A digital voltmeter converts an analog voltage to its ________ representation.

  • BCD-code
  • decimal
  • digital
  • alias
Q.5

Resolution in the analog output of a DAC is primarily dependent on the number of input binary bits.

  • True
  • False
Q.6

A sample-and-hold circuit is used in D/A conversion.

  • True
  • False
Q.7

The input of an analog-to-digital converter is ________.

  • a voltage level
  • a clock pulse
  • a binary number
  • any of the above
Q.8

An actuator is usually a device that:

  • converts analog data to meaningful digital data.
  • controls a physical variable.
  • stores digital data and then processes that data according to a set of specified instructions.
  • converts a physical variable to an electrical variable.
Q.9

Which of the following characterizes an analog quantity?

  • Discrete levels represent changes in a quantity.
  • Its values follow a logarithmic curve.
  • It can be described with a finite number of steps.
  • It has a continuous set of values over a given range.
Q.10

The main advantage of the tracking A/D converter over the stairstep-ramp A/D converter is that ________.

  • it does not require a counter
  • it uses an up/down counter to indicate the polarity of the input voltage
  • it uses an up/down counter to measure both positive and negative voltages
  • it is faster
Q.11

What is the maximum conversion time for an 8-bit successive-approximation ADC with a clock frequency of 20 kHz?

  • 12.8 ms
  • 6.4 ms
  • 0.05 ms
  • 0.4 ms
Q.12

A signal ________ is produced by sampling the signal at a rate less than the minimum rate identified by Nyquist.

  • Nyquist
  • sampling frequency
  • basis
  • alias
Q.13

The primary disadvantage of the simultaneous A/D converter is ________.

  • that it requires the input voltage to be applied to the inputs simultaneously
  • the long conversion time required
  • the large number of output lines required to simultaneously decode the input voltage
  • the large number of comparators required to represent a reasonable-sized binary number
Q.14

To be useful, A/D or D/A converters must have meaningful representation of the analog quantity and a digital representation and the digital quantity as an analog representation.

  • True
  • False
Q.15

In a binary-weighted D/A converter the sum of all the currents from the binary weighted resistors flows through the operational amplifier.

  • True
  • False
Q.16

The number of binary bits at the input of a DAC or the output of an ADC is known as ________.

  • accuracy
  • linearity
  • resolution
  • monotonicity
Q.17

The primary disadvantage of the flash A/D converter is the large number of comparators required.

  • True
  • False
Q.18

The output of an analog-to-digital converter is a voltage level.

  • True
  • False
Q.19

A(n) ________ converts an analog input to a digital output.

  • ADC
  • DAC
  • flash converter
  • bipolar converter
Q.20

A counter-ramp ADC stops counting when ________.

  • the input voltage equals the DAC staircase voltage
  • the counter reaches a maximum count
  • the input voltage equals 5 volts
  • the DAC staircase voltage equals 5 volts
Q.21

For each bit that is added to a digital ramp ADC, the conversion time ________.

  • doubles
  • triples
  • decreases by one-third
  • decreases by one-half
Q.22

Electrical quantities can be interpreted without conditioning by a digital computer.

  • True
  • False
Q.23

The amount of deviation of the measured step size from the ideal step size is a measure of linearity.

  • True
  • False
Q.24

Generally speaking, DACs with a current output will have a shorter settling time than those with voltage outputs.

  • True
  • False
Q.25

A light bulb and a switch are examples of an analog circuit.

  • True
  • False
Q.26

An eight-bit D/A converter has a resolution of 0.125.

  • True
  • False
Q.27

A summing op-amp can be used for DAC.

  • True
  • False
Q.28

A CD player probably uses a sigma/delta D/A converter.

  • True
  • False
Q.29

When the inputs of a four-bit D/A converter are connected to a binary up-counter, the output looks like an upward sloping line.

  • True
  • False
Q.30

________ DACs produce both positive and negative output values.

  • Tristate
  • Double
  • Bipolar
  • Unilateral
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