RP-SYN: synthesis of random pattern testable circuits with test point insertion

An automated logic synthesis procedure, called RP-SYN, is described for synthesizing random pattern testable circuits. RP-SYN takes as an input a two-level description of a circuit and a constraint on the minimum fault detection probability (threshold below which faults are considered random pattern-resistant), and generates a multilevel implementation which satisfies the constraint while minimizing the literal count. RP-SYN identifies random-pattern-resistant faults and eliminates them through testability-driven factoring combined with test point insertion. By moving the task of test point insertion from the back-end into the synthesis process, RP-SYN reduces design time and enables better optimization of the resulting implementation. Results are shown for benchmark circuits which indicate that RP-SYN can generally reduce the random pattern test length by at least an order of magnitude with only a small area overhead.