Versatile BIST: an integrated approach to on-line/off-line BIST

In this paper we report a versatile BIST approach (VBIST) that targets both off-line and on-line self test. VBIST uses off-line BIST circuitry for on-line testing as well. Unlike traditional on-line self test approaches, VBIST does not use functional data as test inputs. Rather, VBIST generates test patterns and compacts test responses during the normal mode of operation. Furthermore, VBIST coordinates this generation and application of test patterns and compaction of test responses with the usage profile of the modules in the design. VBIST entails little additional impact on performance and area of the design (vis-a-vis the performance and area of a design with off-line BIST). We validated the VBIST approach using the Synopsys Behavioral Compiler as the synthesis framework and by writing synthesis scripts for incorporating VBIST constraints