Determine the worst-case propagation delay for your

Question

• Draw the AND gates in the full adder?

Question 1(a)
Sketch a combinational circuit which takes as input, two 4-bit binary numbers, A₃A₂A₁A₀ and B₃B₂B₁B₀, and which outputs the 8-bit product P₇P₆P₅P₄P₃P₂P₁P₀•

Assume that you have available sixteen 2-input AND gates and three 4-bit adders.

Please explain the reasoning behind your design.

The circuit symbol for the 4-bit adder is shown in Figure 1. Note that C0 is the carry-in and C4 is the carry-out.

Question 1(b)

Assuming that each 4-bit adder is implemented by cascading four full adders together (with no carry lookahead), determine the worst-case propagation delay for your combinational multiplier. You can assume that the delay through every full adder is t_pd.