Debug 2-Bit Carry Lookahead Adder
A carry lookahead adder (CLA) improves speed by calculating carry signals in advance based on generate and propagate logic.
Expected behavior:
The circuit must correctly add two 2-bit numbers A and B with a carry-in Cin to produce a 2-bit sum S and a carry-out Cout. The outputs follow the standard arithmetic addition equation: {Cout, S1, S0} = {A1, A0} + {B1, B0} + Cin.
Simulation shows S1 = 0, S0 = 1, and Cout = 0 for input A1=0, A0=1, B1=0, B0=0, Cin=1. The expected output is S1 = 1, S0 = 0, and Cout = 0. The carry fails to propagate correctly through the first bit position. Inspect the circuit and correct the fault.
Constraints
- Do not change the overall architecture to a ripple carry adder.
- Maintain the existing carry lookahead logic structure.
- Only replace the single faulty logic gate.
Topics
Solve this problem
Place the gates, wire them up and watch the signals settle. Every submission runs on the same simulation engine that grades it.
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