A Systems Approach to Specifying Built-in Tests

The need for specifying robust built-in test for systems is growing as systems become more complex. Further, detection-only BIT—the predominant form of BIT—is insufficient to meet the needs of system test on current and future systems; localization and even isolation is becoming essential. In response to this need, several computerbased analysis tools have become available that provide the ability to assess system testability and BIT effectiveness. Yet few if any formal methods exist for providing optimal BIT specifications. In this paper, we explore two BIT figures of merit—test point utilization and optimized resolution analysis. We will describe evaluation measures which we then apply to BIT specified using these two approaches and explain the resulting differences.