Digital logic: gates, K-maps & flip-flops worksheet with answers

Free printable Digital logic: gates, K-maps & flip-flops worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

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1.Easy
A = 1B = 0C = 1N1G1G2G3F

The inputs of the logic circuit are A = 1, B = 0 and C = 1. Exactly one of its gates has the output 1. Click that gate.

A = 1B = 0C = 1
  1. 1N1
  2. 2G1
  3. 3G2
  4. 4G3
2.Easy
A = 0B = 1C = 0N1G1G2G3F

The inputs of the logic circuit are A = 0, B = 1 and C = 0. Exactly one of its gates has the output 0. Click that gate.

A = 0B = 1C = 0
  1. 1N1
  2. 2G1
  3. 3G2
  4. 4G3
3.Medium
ABCD000111100001111010010302141507160121131151140819011110

Use the Karnaugh map to find the minimal product-of-sums (POS) form of F(A, B, C, D) = Σm(0, 4, 5, 6, 9, 10, 13, 14, 15). How many sum terms (factors) N does it have?

F(A, B, C, D) = Σm(0, 4, 5, 6, 9, 10, 13, 14, 15)
N =
4.Medium
ABCD000111100001111000111302140517060120130150141809111010

Use the Karnaugh map to find the minimal sum-of-products (SOP) form of F(A, B, C, D) = Σm(1, 3, 4, 7, 8, 11). How many product terms N does it have?

F(A, B, C, D) = Σm(1, 3, 4, 7, 8, 11)
N =
5.Hard
CLKT1234567

A positive-edge-triggered T flip-flop starts with Q = 0 and receives the inputs shown at 7 rising clock edges. How many times N does Q change state?

Q₀ = 0T
N =
6.Hard
CLKJK1234567

A positive-edge-triggered JK flip-flop starts with Q = 0 and receives the inputs shown at 7 rising clock edges. How many times N does Q change state?

Q₀ = 0JK
N =

Answer key

  1. 1. G1
  2. 2. G1
  3. 3. N = 5
  4. 4. N = 5
  5. 5. N = 2
  6. 6. N = 4

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