GATE Digital Logic 5

Question 1

Which of the following correctly describes a tri-state buffer?

Accepted Answer

Can output 0, 1, or high-impedance

Answer

A tri-state buffer outputs logic 0, logic 1, or high-impedance (Z) depending on its enable signal.

Question 2

The hexadecimal number 2F is equivalent to which decimal value?

Accepted Answer

47

Answer

2F hex = 2×16 + 15 = 32 + 15 = 47 in decimal.

Question 3

A Moore machine's output depends on:

Accepted Answer

Current state only

Answer

In a Moore machine, outputs are a function of the current state alone, not the inputs.

Question 4

What is the minimum number of flip-flops needed to build a MOD-10 counter?

Accepted Answer

4

Answer

MOD-10 requires 10 states; since 2^3=8 < 10 ≤ 2^4=16, at least 4 flip-flops are needed.

Question 5

Which of the following combinational circuits selects one of many inputs and routes it to a single output?

Accepted Answer

Multiplexer

Answer

A multiplexer (MUX) selects one of multiple input lines and forwards it to a single output based on select signals.

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