This set of Digital Circuits Multiple Choice Questions & Answers (MCQs) focuses on “K-Map Simplification”.

1. Which of the examples below expresses the commutative law of multiplication?

a) A + B = B + A

b) A • B = B + A

c) A • (B • C) = (A • B) • C

d) A • B = B • A

2. The Boolean expression Y = (AB)’ is logically equivalent to what single gate?

a) NAND

b) NOR

c) AND

d) OR

3. Which statement below best describes a Karnaugh map?

a) It is simply a rearranged truth table

b) The Karnaugh map eliminates the need for using NAND and NOR gates

c) Variable complements can be eliminated by using Karnaugh maps

d) A Karnaugh map can be used to replace Boolean rules

4. The observation that a bubbled input OR gate is interchangeable with a bubbled output AND gate is referred to as __________________

a) A Karnaugh map

b) DeMorgan’s second theorem

c) The commutative law of addition

d) The associative law of multiplication

5. Each “1” entry in a K-map square represents _______________

a) A HIGH for each input truth table condition that produces a HIGH output

b) A HIGH output on the truth table for all LOW input combinations

c) A LOW output for all possible HIGH input conditions

d) A DON’T CARE condition for all possible input truth table combinations

6. Which of the following statements accurately represents the two BEST methods of logic circuit simplification?

a) Actual circuit trial and error evaluation and waveform analysis

b) Karnaugh mapping and circuit waveform analysis

c) Boolean algebra and Karnaugh mapping

d) Boolean algebra and actual circuit trial and error evaluation

7. The systematic reduction of logic circuits is accomplished by _______________

a) Symbolic reduction

b) TTL logic

c) Using Boolean algebra

d) Using a truth table

8. Each “0” entry in a K-map square represents _______________

a) A HIGH for each input truth table condition that produces a HIGH output

b) A HIGH output on the truth table for all LOW input combinations

c) A LOW output for all possible HIGH input conditions

d) A DON’T CARE condition for all possible input truth table combinations

9. Looping on a K-map always results in the elimination of __________

a) Variables within the loop that appear only in their complemented form

b) Variables that remain unchanged within the loop

c) Variables within the loop that appear in both complemented and uncomplemented form

d) Variables within the loop that appear only in their uncomplemented form

10. Which of the following expressions is in the sum-of-products form?

a) (A + B)(C + D)

b) (A * B)(C * D)

c) A* B *(CD)

d) A * B + C * D

11. Which of the following is an important feature of the sum-of-products form of expressions?

a) All logic circuits are reduced to nothing more than simple AND and OR operations

b) The delay times are greatly reduced over other forms

c) No signal must pass through more than two gates, not including inverters

d) The maximum number of gates that any signal must pass through is reduced by a factor of two

12. Which of the following expressions is in the product-of-sums form?

a) (A + B)(C + D)

b) (AB)(CD)

c) AB(CD)

d) AB + CD