Research And Design Of Fault Detection&Demonstration System Based On Boundary-Scan Technology

As the development of the large scale integrated circuit is vigorous,its application gets wide so that the intensity of circuit board&surface mount gets more complex. As the chip package gets more and more sophisticated and its pins get more intensive,there come such series of fault as open or short circuit components installed in wrong direction or wrong components choiced when the circuit board is soldered.It is difficult and traditional to use physical means(the electrical performance is tested by using physical probe contacts to the wire mesh of the circuit board)to achieve effective test of such circuit board,or even damage the more complex circuit board. To aim at those faults of the complex and intensive circuit board,the popular solution is the Boundary Scan Technology. The core idea of the technology is to put the boundary-scan cells between the pins and internal logic circuit of the chips,the boundary-scan cells are composed by the shift registers,and can load the test vectors and capture the corresponding vectors.The technology was accepted by IEEE,in1991and then was called IEEE1149.1standard. This standard provides standard test access ports and boundary-scan structure for the digital integrated circuit.It is not only to support the testing of the board level&complex integrated circuit or high-density surface mount technology,but also to provide testing access and control methods for the embedded&testing digital integrated circuit. This standard was accepted by lots of IC manufactures when appeared soon,then,there came a lot of equipment with the boundary-scan test structure in the market.Now it is the important structure features of the computer-aided design tool and is used in the circuit simulation debugging and troubleshooting. This topic uses the most widely used ARM and FPGA processor as central controller to detect the faults of more complex&intensive circuit board by using boundary-scan technology,and fanally design a set of practical demonstration system for fault detection.The system makes the device-level,board-level,equipment-level fault to get self-detection and isolation through the scan chain,and complete the detection &isolation of all levels of the system faults through the combination of the automatic testing system.In order to achieve better effect demonstration of the system faults,this paper design special module to simulate the anticipated faults to detect the practical&flexible applicability of the designed system.