Digital Logic and Design MCQs with Answers
Practice important Digital Logic and Design MCQs with answers and explanations.
Chapter: 23
Q521:
The state of the flip-flop in an edge-triggered D flip-flop changes ________.
A. On the falling edge of the clock pulse
B. On the rising edge of the clock pulse
C. At the negative edge of the clock pulse
D. At any change in the clock pulse
Correct Answer:
B
Chapter: 23
Q522:
What does the term 'debouncing' refer to in digital electronics?
A. Filtering noise from the signal
B. Stabilizing a signal to avoid multiple transitions due to mechanical switch bounce
C. Increasing signal strength
D. Reducing signal interference
Correct Answer:
B
Chapter: 24
Q523:
What is the advantage of using edge-triggered D-flip-flops in a parallel-to-serial converter?
A. They allow changes in data before the clock transition to be stored
B. They store data precisely at the clock transition
C. They require less clock cycles for data conversion
D. They increase the enable time of the latches
Correct Answer:
B
Chapter: 24
Q524:
What happens to the data stored in a D-flip-flop if the data changes after the clock transition?
A. The data in the flip-flop is updated
B. The data in the flip-flop remains stable
C. The data in the flip-flop is cleared
D. The flip-flop enters a transparent mode
Correct Answer:
B
Chapter: 24
Q525:
In a D-latch, what mode is the latch in when the enable signal is activated?
A. Latched Mode
B. Transparent Mode
C. Reset Mode
D. Undefined Mode
Correct Answer:
B
Chapter: 24
Q526:
What is the main demerit of using gated D-latches in parallel-to-serial conversion?
A. Extended enable time
B. Increased data loss during conversion
C. Increased complexity in design
D. Reduced data stability during conversion
Correct Answer:
A
Chapter: 24
Q527:
How does a D-flip-flop improve the stability of parallel-to-serial conversion compared to a gated D-latch?
A. By increasing the enable time of the latch
B. By storing data precisely at the clock transition
C. By allowing data changes to be reflected immediately
D. By requiring fewer clock cycles for conversion
Correct Answer:
B
Chapter: 24
Q528:
What is the primary function of a D-flip-flop in synchronizing asynchronous inputs?
A. To prevent incomplete or partial pulses from appearing
B. To amplify the input signal
C. To debounce the input switch
D. To delay the clock signal
Correct Answer:
A
Chapter: 24
Q529:
How does a D-flip-flop synchronize an asynchronous input signal?
A. By making the input signal synchronous with the clock
B. By generating an additional clock pulse
C. By amplifying the input signal
D. By increasing the switching frequency
Correct Answer:
A
Chapter: 24
Q530:
What is a primary application of using J-K flip-flops in digital circuits?
A. To act as a basic storage element
B. To divide frequency
C. To perform arithmetic operations
D. To implement memory cells
Correct Answer:
B
Chapter: 24
Q531:
How does a J-K flip-flop operate when both J and K inputs are set to logic 1?
A. It maintains the previous state
B. It sets Q to 1 and Q to 0
C. It toggles the state of Q and Q
D. It resets Q to 0 and Q to 1
Correct Answer:
C
Chapter: 24
Q532:
What happens to the output of a J-K flip-flop when J=0 and K=1?
A. The output Q is set to 1 and Q to 0
B. The output Q is set to 0 and Q to 1
C. The output remains unchanged
D. The output toggles between 0 and 1
Correct Answer:
B
Chapter: 24
Q533:
How does a J-K flip-flop behave when J=1 and K=0?
A. It resets the output to Q=0 and Q=1
B. It sets the output to Q=1 and Q=0
C. It toggles the output between 1 and 0
D. It maintains the previous state
Correct Answer:
B
Chapter: 24
Q534:
What is the function of a J-K flip-flop used as a frequency divider?
A. To multiply the input frequency
B. To divide the input frequency
C. To synchronize different parts of the circuit
D. To store data temporarily
Correct Answer:
B
Chapter: 24
Q535:
What is the advantage of using J-K flip-flops as a shift register?
A. To perform binary multiplication and division by shifting bits
B. To store multi-bit binary data in parallel
C. To synchronize asynchronous inputs
D. To prevent multiple transitions of input data
Correct Answer:
A
Chapter: 24
Q536:
How can J-K flip-flops be used in a counter application?
A. By counting up or down with each clock signal
B. By storing multi-bit data
C. By converting parallel data to serial data
D. By synchronizing different frequency signals
Correct Answer:
A
Chapter: 24
Q537:
What is the primary purpose of using a J-K flip-flop as a sequence detector?
A. To detect a specific sequence of inputs
B. To divide the clock frequency
C. To store multi-bit binary information
D. To synchronize asynchronous inputs
Correct Answer:
A
Chapter: 25
Q538:
What are S-R, J-K, and D inputs in a flip-flop commonly referred to as?
A. Asynchronous inputs
B. Synchronous inputs
C. Digital inputs
D. Clock inputs
Correct Answer:
B
Chapter: 25
Q539:
What is the function of asynchronous inputs in a flip-flop?
A. Operate with the clock
B. Override synchronous inputs
C. Synchronize inputs
D. Disable flip-flop
Correct Answer:
B
Chapter: 25
Q540:
Which input sets the flip-flop to Q=1 and Q=0?
A. PRE set to 1, CLR set to 1
B. PRE set to 0, CLR set to 1
C. PRE set to 1, CLR set to 0
D. PRE set to 0, CLR set to 0
Correct Answer:
B