ECE QUIZ :4

Online Examination for ECE Quiz Question And Answer

Online Test

1. Which of the following characterizes an analog quantity?

Discrete levels represent changes in a quantity
Its values follow a logarithmic response curve
It can be described with a finite number of steps
It has a continuous set of values over a given range
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2. If a signal passing through a gate is inhibited by sending a low into one of the inputs, and the output is HIGH, the gate is a(n)

AND
NAND
NOR
OR
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3. What is the standard TTL noise margin?

5.0 V
0.2 V
0.8 V
0.4 V
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4. The determination of a digital signal's frequency and waveshape is best accomplished with which test equipment?

an oscilloscope
a multimeter
a spectrum analyzer
a frequency generator
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5. What are the two types of basic adder circuits?

half adder and full adder
half adder and parallel adder
asynchronous and synchronous
one's complement and two's complement
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6. A 4-bit R/2R digital-to-analog (DAC) converter has a reference of 5 volts. What is the analog output for the input code 0101.

0.3125 V
3.125 V
0.78125 V
13.125 V
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7. The difference between analog voltage represented by two adjacent digital codes, or the analog step size, is the

quantization
accuracy
resolution
monotonicity
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8. The primary disadvantage of the flash analog-to digital converter (ADC) is that

it requires the input voltage to be applied to the inputs simultaneously
a long conversion time is required
a large number of output lines is required to simultaneously decode the input voltage
a large number of comparators is required to represent a reasonable sized binary number
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9. A binary-weighted digital-to-analog converter has a feedback resistor, Rf, of 12 komega.gif. If 50 mu.gifA of current is through the resistor, the voltage out of the circuit is

0.6 V
–0.6 V
0.1 V
–0.1 V
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10. What is the major advantage of the R/2R ladder digital-to-analog (DAC), as compared to a binary-weighted digital-to-analog DAC converter?

It only uses two different resistor values
It has fewer parts for the same number of inputs.
Its operation is much easier to analyze
The virtual ground is eliminated and the circuit is therefore easier to understand and troubleshoot
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