ISCET Digital Electronics Principles 2

Question 1

What is the output of a NAND gate when both inputs are HIGH?

Accepted Answer

LOW

Answer

A NAND gate outputs LOW only when all inputs are HIGH, making it the complement of an AND gate.

Question 2

Which number system uses base 16 with digits 0–9 and letters A–F?

Accepted Answer

Hexadecimal

Answer

Hexadecimal (base-16) uses digits 0–9 and letters A–F to represent values 0 through 15.

Question 3

In a D flip-flop, what happens to the output Q on the active clock edge when D = 0?

Accepted Answer

Q becomes 0

Answer

A D flip-flop transfers the D input directly to Q on the active clock edge, so Q = 0 when D = 0.

Question 4

What Boolean expression represents a 2-input XOR gate?

Accepted Answer

A⊕B = A'B + AB'

Answer

XOR (exclusive-OR) outputs HIGH when inputs differ: A'B + AB' is the canonical SOP form.

Question 5

How many bits are required to uniquely represent 32 different states?

Accepted Answer

5

Answer

2⁵ = 32, so exactly 5 bits are needed to represent 32 unique states.

(ISCET) International Society of Certified Electronics Technicians Practice Test