Frequency-domain compatibility in digital filter BIST
Laurence Goodby, Alex Orailoğlu · 1997
We examine frequency-domain issues in the design and selectionof on-chip test generators for built-in self-test (BIST) of high-performancedigital filters. Test-generator/circuit compatibility isidentified as a significant factor in testing large filters. A fault-injectionexperiment is used to show that when an incompatible testgenerator is used, high fault coverage (over 99%) does not guaranteethat all serious faults will be detected. The frequency-domaincharacteristics of some basic test generation schemes are examined,and guidelines for test generator selection are proposed. Analyticaltechniques for identifying frequency-related testability problemsare discussed, and several test generation schemes are evaluated byfault simulating them against lowpass, bandpass, and highpass filters.A mixed test generation scheme is shown to reduce the numberof untested faults by a factor of two to three over a standard linear-feedbackshift-register (LFSR) based test scheme, at little added cost.