Smart build-in-test using the BITSI technique
G.C. Bergeson · 1989
This report describes a built-in-test technique called Built-In-Test by Signature Inspection (BITSI) used to pinpoint the source of faults within digital circuits. BITSI is implemented using simple, digital logic which resides on the same printed circuit board as the circuit under test. BITSI is an active technique which does not influence normal operation of the circuit board. When the BITSI logic is activated, it switches the circuit under test off-line, applies a test stimulus to the circuit, and measures circuit response at various test nodes. If the response is abnormal, BITSI will isolate the fault to the circuit node which generated the fault. BITSI has many advantages, including real-time test speed: it is fully automated and self-contained on the printed circuit board under test; it requires no external test equipment; it tests for faults in the test hardware; it is highly reliable and is easily applicable to most digital circuits. 8 refs., 15 figs., 6 tabs.