Digital Logic and Systems Flashcards
7 cards from real BEE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Digital Logic and Systems flashcards as text
Which minimization technique uses a tabular method to find the prime implicants of a Boolean function?
Answer: Quine-McCluskey method
The Quine-McCluskey method is a tabular algorithm for finding all prime implicants, useful for functions with many variables where K-maps become impractical.
In a JK flip-flop, what is the output when both J=1 and K=1?
Answer: Toggle (Q changes state)
When J=K=1, the JK flip-flop toggles its output on each clock edge, which eliminates the undefined state of the SR flip-flop.
A 4-bit ripple carry adder adds two numbers in how many gate delays compared to a carry look-ahead adder?
Answer: More gate delays
A ripple carry adder propagates carry serially through each stage, resulting in more gate delays than a carry look-ahead adder which computes carries in parallel.
Which of the following is a universal gate?
Answer: NAND gate
NAND (and NOR) gates are universal because any Boolean function can be implemented using only NAND gates.
In a Moore machine, the output depends on:
Answer: Current state only
In a Moore machine, outputs are a function of the current state only, making them synchronous with the clock.
What does a tri-state buffer output when its enable signal is inactive?
Answer: High impedance (Z)
A tri-state buffer enters a high-impedance state when disabled, effectively disconnecting its output from the bus.
How many product terms (minterms) does a 3-variable Boolean function have in total?
Answer: 8
A 3-variable Boolean function has 2³ = 8 possible minterms, one for each combination of input values.