US Patent 8074189 Pruning-based variation-aware design

For application to analog, mixed-signal, and custom digital circuits, a system and method to begin with a complex problem description that encompasses many variables from statistical manufacturing, the circuit's environment, and the circuit's design parameters, but then apply techniques to prune the scope of the problem to make it manageable for manual design and more efficient automated design, and finally use that pruned problem for more efficient and effective design.