Abstract
Auto-Fault-Locating-System for mounting boards has been developed. In this system, faultpropagated nets are detected by comparing pulse-counts and voltages in good boards and fault ones under full power supply. And fault nets, which include the real fault origin, are located by tracing backward via a fault propagation path using the input-output attribute of terminals. With this system, IC functions are not necessary to locate faults and the number of measurement points is smaller than that of measuring all terminals. Measurement requires 1.5 seconds per net, and fault search requires 10-20 seconds. The system successfully located the fault origin in about 60 % of boards rejected in a functional test.
