高集成度多种格式并行输出的视频测试信号源研制

在大规模自动化生产过程中，为了对不同型号的电视机主板进行测试，需要一种能同时输出不同格式、多种接口、多种分辨率的视频测试信号源。通过对多媒体视频传输原理及不同格式视频接口信号的研究，在一片先进的Artix-7系大规模可编程XC7A100T芯片上，实现了超高清、高清的数字视频HDMI接口信号和模拟标清视频VGA、CVBS、YPRPB格式的信号同时输出。首先，根据视频显示的基本原理，产生对应不同分辨率、不同场频的并行数字视频基带信号。然后，将并行的超高清、高清分辨率的数字视频信号进行并串转化，成为串行的TMDS信号，送到HDMI接口显示；将并行标清分辨率的信号送入调制模块及数模转换转器成为CVBS、VGA、YPRPB格式的模拟视频信号。在一片XC7A100T芯片内将并行的超高清、高清数字信号转换成串行差分TMDS信号，节省了视频信号的并串转换处理芯片，节约了成本。整个系统提高了产生视频测试信号的集成度，减小了测试装备的体积，方便生产视频设备的厂家进行测试。

Implementation of the high-integration video signal-source with the multi-format and parallel-output function

In the large-scale automatic production process, in order to test different types of TV motherboards, it is very necessary that video test sources can output different formats, multi-interfaces and multi-resolution in parallel. Through the exploration of multimedia video transmission principle and video signal interface formats, the video test signal source is designed and realized in an advanced Artix-7 series large-scale programmable XC7A100T chip, which can output both ultra-high-definition and high-definition video HDMI interface signal, and analog standard definition video signal in VGA, CVBS and YPRPB format. First of all, parallel digital baseband video signals with different resolutions and field frequencies are generated according to the principle of video display. Then, the parallel ultra-high-definition and high-definition digital video signals are converted into serial TMDS signals in order to be sent to the HDMI interface for display; and the parallel standard resolution signal is sent to the modulation module and digital-to-analog converter to become analog video signal in VGA, CVBS and YPRPB format. In particular, the parallel ultra-high-definition and high-definition digital video signals are converted into serial TMDS differential signal inside the XC7A100T chip, which saves the video parallel-serial processing chips and reduces the cost of equipment. The whole system improves the integration level of video test signal, reduces the volume of test equipment, and the manufacturers of video equipment can be more convenient to test.