2 i egr 2400- hw 1 num. sys./logic gates name 2. for the following circuits, complete the truth table. write the product-of-sums equation for output z of the truth table in problem 2.a. and a sum-of-products equation for the z output in the table in problem 2.b 3.
LectureNotes said 2 i egr 2400- hw 1 num. sys./logic gates name 2. for the following circuits, complete the truth table. write the product-of-sums equation for output z of the truth table in problem 2.a. and a sum-of-products equation for the z output in the table in problem 2.b 3.
To tackle this problem, we need to follow these steps:
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Complete the Truth Table for the Given Circuit:
- Identify the inputs and outputs of the circuit.
- List all possible combinations of input values.
- Determine the corresponding output for each combination based on the logic gates used in the circuit.
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Write the Product-of-Sums (POS) Equation for Output Z:
- Identify the rows in the truth table where the output Z is 0.
- Write the corresponding sum terms (OR terms) for these rows.
- Combine these sum terms using AND operations to form the POS equation.
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Write the Sum-of-Products (SOP) Equation for Output Z:
- Identify the rows in the truth table where the output Z is 1.
- Write the corresponding product terms (AND terms) for these rows.
- Combine these product terms using OR operations to form the SOP equation.
Example Walkthrough
Problem 2.a: Product-of-Sums (POS) Equation
Assume we have a circuit with inputs A, B, and C, and output Z. Let’s complete the truth table for this circuit:
A | B | C | Z |
---|---|---|---|
0 | 0 | 0 | 1 |
0 | 0 | 1 | 0 |
0 | 1 | 0 | 1 |
0 | 1 | 1 | 0 |
1 | 0 | 0 | 1 |
1 | 0 | 1 | 0 |
1 | 1 | 0 | 1 |
1 | 1 | 1 | 0 |
From the truth table, we see that Z is 0 for the following input combinations:
- A = 0, B = 0, C = 1
- A = 0, B = 1, C = 1
- A = 1, B = 0, C = 1
- A = 1, B = 1, C = 1
Each of these conditions can be expressed as a sum term (OR term):
- For A = 0, B = 0, C = 1: ( \overline{A} + \overline{B} + C )
- For A = 0, B = 1, C = 1: ( \overline{A} + B + C )
- For A = 1, B = 0, C = 1: ( A + \overline{B} + C )
- For A = 1, B = 1, C = 1: ( A + B + C )
The POS equation is the AND of these sum terms:
Problem 2.b: Sum-of-Products (SOP) Equation
From the same truth table, we see that Z is 1 for the following input combinations:
- A = 0, B = 0, C = 0
- A = 0, B = 1, C = 0
- A = 1, B = 0, C = 0
- A = 1, B = 1, C = 0
Each of these conditions can be expressed as a product term (AND term):
- For A = 0, B = 0, C = 0: ( \overline{A} \cdot \overline{B} \cdot \overline{C} )
- For A = 0, B = 1, C = 0: ( \overline{A} \cdot B \cdot \overline{C} )
- For A = 1, B = 0, C = 0: ( A \cdot \overline{B} \cdot \overline{C} )
- For A = 1, B = 1, C = 0: ( A \cdot B \cdot \overline{C} )
The SOP equation is the OR of these product terms:
By following these steps, you can derive the POS and SOP equations for any given truth table.