A SIC PAIR GENERATOR FOR A BILBO ENVIRONMENT
Ioannis Voyiatzis, Dimitris Kehagias · Journal of Circuits Systems and Computers · 2006
Built-In Self Test (BIST) techniques are commonly used as an efficient alternative to external testing in today's high-complexity VLSI chips since they provide on-chip test pattern generation and response verification. Among the BIST techniques, Built-In Logic Block Observation (BILBO) has been widely used in practice. Test patterns generated by BILBO structures target the detection of stuck-at faults. It has been shown that most common failure mechanisms that appear into current CMOS VLSI circuits cannot be modeled as stuck-at faults. These mechanisms, modeled by sequential (i.e., stuck-open and delay) faults models, require the application of two-pattern tests (vector pairs) in the circuit-under-test inputs. Single Input Change (SIC) pairs are pairs of patterns where the second pattern differs from the first in only one bit and have been successfully used for two-pattern testing. In this paper we present the BILBO-oriented SIC pair Generator technique that extends BILBO in order to generate SIC pairs; in this way, sequential faults are also detected.