The Study Of Key Technologies In Ground Test Bench Of Data Record Device

The ground test bench is designed for the performance test demands of data recorddevice. The overall design scheme of the test bench is proposed based on the detailedanalysis of its performance index. The main control chip of this system is FPGA, and theUSB interface is responsible for the communication with computer. With the method ofmodular design, the whole ground test bench is divided into power module, signal sourcemodule and main control module which are connected with each other through the powerrear panel. This paper focuses on the study of key technologies during the design process.In the design of main control module, the LVDS interface and command design aredesigned and analyzed particularly. For LVDS interface, the hardware circuit design andlogical time-sequenced design are introduced and further optimal designs are proposed inhardware and software through the analysis of problems encountered in the test process.The reliability design of command transmission is especially introduced in the commanddesign part. The realization of RS-422 communication by FPGA is expounded fromelectrical level standard and communication protocol.In the design of signal source module, the generation scheme of high-speed pulse isparticularly introduced. Based on the analysis of performance index, two design schemeswhich are high-speed op-amp regulate scheme and high-speed electronic switch scheme areput forward. The phenomenon of signal reflection occurred in these two schemes isanalyzed in depth and the solution method is also put forward.Through the overall experiment of ground test bench and recorder device, it can bedemonstrated that the functions of test bench are well and performance is reliable.