In digital design, what is a Karnaugh map and how is it used to simplify Boolean expressions?

• A. A method for sorting truth tables into truth tables.
• B. 2D grid method to minimize logical expressions by grouping 1s to find minimal sum-of-products; reduces logic gates.
• C. A numerical method for solving differential equations.
• D. A tool to compute Fourier transforms.

Answer: (B)

A Karnaugh map is a visualization tool that places the truth table entries where the function is true onto a 2D grid. By grouping these 1s into rectangles whose sizes are powers of two, you identify which variables stay the same across the entire group. Those constant variables form a product term, and combining these product terms gives a simplified sum-of-products expression with fewer literals. Fewer literals mean fewer gates in hardware, so the map helps you minimize the circuit efficiently. Remember that edges wrap around, so groups can span the grid’s boundaries to maximize simplification. This technique isn’t about sorting truth tables, solving differential equations, or computing Fourier transforms.