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Tutorial: ITI1100Dewan Tanvir Ahmed

SITE, UofO

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Question 4-5• Design a combinatorial circuit with three inputs, x, y, and x and

three outputs, A, B, and C. When the binary input is 0, 1, 2, or 3, the binary output is one greater than the input. When the binary input is 4, 5, 6, or 7, the binary output is one less than the input.

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Solution 4-5

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Question 4-6• A majority circuit is a combinatorial circuit whose output is equal

to 1 if the input variables have more 1’s than 0’s. Design a 3-input majority circuit

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Solution 4-6

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Question 4-10• Design a 4-bit combinational circuit 2’s complementer. Show that

the circuit can be constructed using exclusive-OR gates. Can you predict what the output functions are for a 5-bit 2’s complementer?

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Solution 4-10

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Question 4-11• Design a 4-bit combinational circuit incrementer. The circuit can

be designed using 4 half adders.

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Solution 4-11

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Question 4-22• Design a excess-3-to-binary decoder using NOR gates only.

Include an enable input.

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Solution 4-22

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Question 4-27• A combinational circuit is specified by following three Boolean

functions:F1 = (2, 4, 7)F2 = (0, 3)F3 = (0, 2, 3, 4, 7)

Implement the circuit with a decoder constructed with NAND and NAND or AND gates connected to the decoder outputs. Use a block diagram for the decoder. Minimize the number of inputs in the external gates.

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Solution 4-27

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Question 4-32• Implement the following Boolean function with a multiplexer:

F(A, B, C, D) = (0, 1, 3, 4, 8, 9, 15)

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Solution 4-32

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Thank You!