Important Digital Logic and Design Short Questions
Chapter: 27
Question 1:
How does a 4-bit synchronous counter use AND gates in its design?
Answer:
A 4-bit counter uses AND gates to control the state change of the fourth flip-flop based on the outputs of the first three flip-flops, ensuring correct counting at specific intervals.
Chapter: 27
Question 2:
What is the purpose of a synchronous decade counter?
Answer:
A synchronous decade counter counts from 0000 to 1001 and resets to 0000 after reaching 1001, using logic gates to manage the reset function instead of asynchronous clear inputs.
Chapter: 27
Question 3:
How does a synchronous decade counter differ from an asynchronous decade counter?
Answer:
A synchronous decade counter uses a common clock and logic gates for resetting, while an asynchronous decade counter uses separate clear inputs to reset after counting to 1001.
Chapter: 28
Question 4:
What does a synchronous decade counter do?
Answer:
A synchronous decade counter counts from 0000 to 1001, then resets to 0000 using a common clock signal for all flip-flops.
Chapter: 28
Question 5:
How is a Mod-n synchronous counter implemented?
Answer:
It is implemented using J-K flip-flops with their clocks triggered simultaneously, where n=2mn = 2^mn=2m, and mmm is the number of flip-flops.
Chapter: 28
Question 6:
What are the main features of the 74HC163 4-bit synchronous counter?
Answer:
The 74HC163 features parallel data inputs, synchronous clear and load, enable inputs, and ripple clock output for cascading.
Chapter: 28
Question 7:
What happens when the CLR signal is activated in a 74HC163 counter?
Answer:
The CLR signal synchronously resets the counter output to 0000 when active.
Chapter: 28
Question 8:
How does the 74HC163 counter differ from the 74HC160?
Answer:
The 74HC163 has a synchronous clear input, while the 74HC160 has a similar function but is designed as a decade counter.
Chapter: 28
Question 9:
What is the purpose of cascading counters like in the 74HC160 example?
Answer:
Cascading counters allows forming larger counters by connecting the RCO output of one to the ENP/ENT inputs of the next.
Chapter: 28
Question 10:
How can a 74HC163 be configured to count in a truncated sequence, such as Mod-7?
Answer:
The counter can be preset with a specific value and reset to this value upon reaching the maximum count using logic gates.