Reconvergent Fanout Masking
Automatic test pattern generation algorithms struggle significantly when signals split and later recombine. The circuit below features a primary input A that fans out to two parallel logic paths. Path one passes through a buffer to node B. Path two passes through an inverter to node C. Nodes B and C act as inputs to a downstream XOR gate, which drives the final output Y. A stuck-at-1 fault is present at the fanout stem A. Trace the propagation of this fault through both paths. Determine whether the fault can be observed at output Y and identify the masking mechanism.
Constraints
- Assume standard gate delays are zero for static fault analysis.
- The fault at
Ais a permanent stuck-at-1 fault. - The circuit contains no other faults.
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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