Research On Automatic Test System Of Card Function

With the continuous development of integrated circuit technology,today,thousands of doors from the integrated circuit has been developed to the present one million,ten million class level,multi-layer circuit boards,surface mount devices,multi-chip module assembly process makes the application more miniaturized circuit assembly in the form.With the continuous improvement of chip integration and wiring density,board short circuit,short circuit interconnect greatly increasing the possibility of failure.According to statistics,Internet failures have accounted for the failure of more than half of the circuit board.Therefore,in electronic equipment production and maintenance phases,board circuit test to become a very important part.In this paper,17 kinds of the board’s functions for its functional test station hardware and software design.Functional test items include:board current consumption test,LED test,RS-232 test,the DC voltage signal test,resistance test,and Ethernet communications test.By multiplexing relay matrix card and board,it achieve pin-point test between the switch and instrument connections.Hardware,the control unit’s 9S12NE64 use free scale microcontroller to achieve the relay matrix and multiplexer board of control,communications,industrial Ethernet,and were used RS-485,a custom protocol.PC software use NI companies TestStand test sequences written,call module written with Lab VIEW.The system realizes Boards of several tests of basic functional test items,No one involved in the process.Production personnel can understand the board whether or not the test item passed,by test reports.The maximum allowed each board test time 500s,average test time 180s,Compared with manual testing greatly reduces test time.Not only guarantees the quality of the product,but also improve the efficiency of production processes.