PCB functional test system based on virtual instrument

A new PCB functional test system, based on the techniques of virtual instrument and USB bussing, is presented in this paper in order to complete functions of traditional instruments. Hardware here is only utilized to establish the basic testing conditions and gather the response. Boundary scan test is inducted and a new approach is proposed for PCB test. The system consists of the superior PC system, the PCB functional test instrument and the needle-bed structure. The superior PC system controls the whole testing process through USB bus. The PCB functional test instrument is the core of the system. The needle-bed structure connects the measured PCB and the ATS together. The experimental results illustrate that the system in this paper is effective and desirable for PCB functional test. It provides 48 bi-directional digital channels and a group of the serial channels and 20 multiplex switches simultaneously.