# Mixed Signal Testing Quiz

## Take the Challenge!

Print this and answer the questions below. If you miss more than 3, then you are a good candidate for this course.

1. The term “resolution” is typically used to describe which of the following DAC characteristics?

a) Voltage Range
b) Accuracy
c) Number of Bits
d) Maximum Clock Frequency

2. The sine of an angle in a right triangle is the ratio of sides given by:

b) Opposite over hypotenuse

3. Sampling can be used to get information about all of the following except:

a) Signal Amplitude
b) Nyquist frequency of a signal
c) Magnitude of a signal at various frequencies
d) Magnitude of a signal at various frequencies

4. What is the “Fourier Frequency”?

a) The highest frequency component of a frequency spectrum
b) The lowest frequency component of a frequency spectrum
c) The frequency of interest in a frequency spectrum
d) The frequency resolution of a frequency spectrum

5. Time Windowing functions can be used to reduce:

a) Voltage Range
b) Spectral leakage
c) Distortion
d) Quantization error

6. The following is a requirement for coherent sampling:

a) A high bandwidth waveform digitizer
b) An integer number of signal cycles
c) Samples from more than one cycle of a signal
d) A lowpass filter

7. A filter’s “3dB point” is:

a) The frequency at which the signal is completely attenuated
b) The frequency at which the signal is not attenuated at all
c) The frequency at which half the signal power is attenuated
d) The frequency at which half the signal voltage is attenuated

8. Which of the following is not a Differential Nonlinearity test method for Analog-to-Digital Converters?

a) Servo Loop
b) Segmented Input Ramp
c) Histogramming
d) Thermal Tail

9. A DAC LSB is calculated as:

a) (Full scale output – zero scale output) * (2bits – 1)
b) (Full scale output – zero scale output) / (2bits – 1)
c) (Full scale output – zero scale output) / 2bits
d) Full scale output / bits

10. A Sine Histogram test is often used to:

a) Find superposition problems with R/2R DACs
b) Find distortion problems with sigma-delta ADCs
c) Find noise problems with partially decoded DACs
d) Find sparkling problems with flash ADCs

a) 45°
b) 90°
c) 180°
d) 360°

12. A low pass filter with 6 poles has a voltage roll-off of:

b) 120dB per octave
d) 6dB per octave

13. A value of 80dB represents a ratio in volts of

a) 10000 : 1
b) 80 : 1
c) 8 : 1
d) 4 : 1

14. The frequency resolution of a spectrum, FF, is given by:

a) Ft / M
b) Fs / N
c) 1 / UTP
d) All of the above

15. The Fast Fourier Transform uses how many calculations?

a) N2 calculations
b) (N / 2) log2 N
c) (N / 2) log10 N
d) (N) log2 N

16. For a given Ft and Fs, what is the effect of increasing M?

a) The number of samples N is decreased, leading to lower frequency domain resolution
b) The number of samples N is increased, leading to higher frequency domain resolution
c) The Unit Test Period is decreased, leading to lower test time
d) The Fourier Frequency is increased, leading to higher noise measurements

17. What is a “sparkle code”?

a) A glitch in a DAC’s output due to superposition error
b) A glitch in an ADC’s output due to superposition error
c) A glitch in an ADC’s output due to illegal states in the output decoder
d) A glitch in a DAC’s output due to major carry transitions

18. A device LSB for an ADC is calculated from the:

a) Zero and full scale measurements
b) Gain measurement
c) Zero and full scale transition measurements
d) Datasheet

19. using the histogram method to test an ADC, “average hits per code” is analogous to:

a) Total number of samples taken
b) DNL
c) Device LSB
d) Tester LSB

20. To use a 12-bit waveform digitizer to dynamically test a 14-bit DAC, you will probably need

a) Waveform generator
b) Notch filter
c) Phase locked loop
d) Bandpass filter