# MCQs on Digital to Analog Converters

1 - Question

What is the form in which audio files are stored?
a) Digital
b) Semi-digital
c) Analog
d) Semi-Analog
Explanation: The audio files are stored in digital format. Computer or any other storage device can only understand and store the binary digits (i.e) 0 and 1, the audio or the sound waves are converted into digital data which is a combination of many 0 and 1. Thus digital data can be stored in any storage device.

2 - Question

Which conversion takes place when music is played from a memory card?
a) AAC
c) DDC
d) DAC
Explanation: DAC conversion takes place when music is played from a memory card. Computer or any memory storing device only understand the binary language which is a combination of many 0 and 1. Any information that has to be stored should be converted into binary digits. The output of any music player is analog signal. Therefore digital to analog conversion (DAC) takes place music is played from a memory card.

3 - Question

What is the output of a music player?
a) Digital
b) Semi-digital
c) Analog
d) Semi-Analog
Explanation: Output of a music player is analog signal. Music or any type of sound is an example of analog signal. The sound signal of music contains many crests and troughs which makes it analog signal. advertisement

4 - Question

What does PWM stand for?
a) Pulse Width modulation
b) Pulsating Width modulation
c) Pulse Width modulator
d) Pulsating Width modulator
Explanation: PWM stands for pulse width modulation. It is a process by which the digital signals are converted to analog signal. In this process the duty cycle of the signal is varied. This varied signal acts as analog signal.

5 - Question

What is the duty cycle of a signal if the pulse width is 0.4 seconds and the time period is 0.8 second?
a) 60%
b) 50%
c) 40%
d) 20%
Explanation: Given: Pulse width=0.4 seconds Time period=0.8 second Duty cycle=(pulse width/time period)*100%. Duty cycle => 0.4/0.8=0.5*100%=50%.

6 - Question

What is the duty cycle of a signal if the pulse width is 0.008 seconds and frequency is 50 hertz?
a) 60%
b) 50%
c) 40%
d) 20%
Explanation: Given: Pulse width=0.008 seconds Frequency=50 hertz Time period=1/frequency Time period=1/50= 0.02 Duty cycle=(pulse width /time period)*100%. Duty cycle => 0.008/0.02=0.4*100%=40%.

7 - Question

What is the duty cycle of a signal if the ON time of the signal is 0.5 seconds and off time of the signal is 0.5 seconds?
a) 60%
b) 50%
c) 40%
d) 20%
Explanation: Given: ON time=0.5 seconds Off time=0.5 seconds Duty cycle=(ON time / total time period)*100%. Total time period=ON time + Off time=>1 Duty cycle => 0.5/1=0.5*100%=50%.

8 - Question

Which of the integrated circuit mentioned below is the name of a Digital to Analog converter?
a) BC541
b) MCP4725
c) TIP122
d) TIP135
Explanation: MCP4725the name of a Digital to Analog converter. It has 12 bit resolution. It supports I2C communication protocol. It also has an internal EEPROM to store the settings. It works on 2.2V to 5.7V input.

9 - Question

What is the duty cycle of a signal if the pulse width is 0.004 seconds and frequency is 50 hertz?
a) 60%
b) 50%
c) 40%
d) 20%
Explanation: Given: pulse width=0.004 seconds Frequency=50 hertz Time period=1/frequency Time period=1/50=0.02 Duty cycle=(pulse width/time period)*100%. Duty cycle => 0.004/0.02=0.2*100%=20%.

10 - Question

What is the duty cycle of a signal if the pulse width is 0.3 seconds and the time period is 0.6 second?
a) 60%
b) 50%
c) 40%
d) 20%
Explanation: Given: Pulse width=0.3 seconds Time period=0.6 second Duty cycle=(pulse width /time period)*100%. Duty cycle => 0.3/0.6=0.5*100%=50%.

11 - Question

What is the duty cycle of a signal if the ON time of the signal is 0.7 seconds and off time of the signal is 0.3 seconds?
a) 60%
b) 70%
c) 40%
d) 20%
Explanation: Given: ON time=0.7 seconds Off time=0.3 seconds Duty cycle=(ON time / total time period)*100%. Total time period=ON time + Off time=>1 Duty cycle => 0.7/1=0.7*100%=70%.

12 - Question

Which is an example of Digital to Analog converter module?
a) PCF8591
b) TMS320F2809PZA
c) RD-KL25-AGMP01
d) DM388AAARD21
Explanation: PCF8591 is an example of Digital to Analog converter module. DM388AAARD21 is an example of Digital media processor. It is manufactured by the “Texas Instruments”. TMS320F2809PZA is an example of Digital signal controller. RD-KL25-AGMP01 is an example of data logger kit.

13 - Question

The highest voltage value of an analog signal is replaced by “logic 1” in digital signal.
a) True
b) False
Explanation: The highest voltage value of an analog signal is replaced by “logic 1” in digital signal. Digital signal can only represent 2 values that are logic 1 and logic 0. Logic 1 represents high voltage whereas logic 0 represents low voltage.

14 - Question

We cannot store analog data directly.
a) True
b) False