Digital Electronics - Digital Concepts
Digital Electronics - Digital Concepts
11. Parallel format means that:
- each digital signal has its own conductor.
- several digital signals are sent on each conductor.
- both binary and hexadecimal can be used.
- no clock is needed.
12. A decoder converts ________.
- noncoded information into coded form
- coded information into noncoded form
- HIGHs to LOWs
- LOWs to HIGHs
13. A DAC changes ________.
- an analog signal into digital data
- digital data into an analog signal
- digital data into an amplified signal
- none of the above
14. The output of a NOT gate is HIGH when ________.
- the input is LOW
- the input is HIGH
- the input changes from LOW to HIGH
- voltage is removed from the gate
15. 15. The output of an OR gate is LOW when ________.
- all inputs are LOW
- any input is LOW
- any input is HIGH
- all inputs are HIGH
16. Which of the following is not an analog device?
- Thermocouple
- Current flow in a circuit
- Light switch
- Audio microphone
17. A demultiplexer has ________.
- one data input and a number of selection inputs, and they have several outputs
- one input and one output
- several inputs and several outputs
- several inputs and one output
18. A flip-flop has ________.
- one stable state
- no stable states
- two stable states
- none of the above
19. Digital signals transmitted on a single conductor (and a ground) must be transmitted in:
- slow speed.
- parallel.
- analog.
- serial.
20. In a certain digital waveform, the period is four times the pulse width. The duty cycle is ________.
- 0%
- 25%
- 50%
- 100%