基于VXI总线用DDS+PLL技术实现精密时钟源

DDS（直接数字频率合成）技术是一门在频率合成领域的新兴技术，具有响应时间短，
精度高等优点。而PLL（Phase Locked Loop）锁相环技术虽然工作速度慢，但稳定可靠。VXI 总线具有灵活、体积小、可移植好等特点，VXI 总线测试平台是21 世纪公认的仪器总线系统和自动测试系统的优秀平台。VXI 总线模块仪器的优点是宜于集成为不同用途的自动测试系统，具有优良的交互操作性，数据传输速率高，可靠性高，易维修，体积小，重量轻，功耗低，可移动性好，价格与传统的自动测试系统相比具有巨大的竞争潜力。
关键词：VXI 总线；DDS；PLL；精密时钟

Abstract： DDS is a new technique in the field of frequency synthesis. It owns the merits of
shorter response time, high accuracy, and so on. Though the converting speed of PLL is low, it works very stable. VXI bus owns the merits of smaller dimension, better transplanting ability, and so on. It is excellent instrument platform in 21st century, it has shown huge power of market competition with the merits of lower consumption, very good instinct of movable and its price compared with traditional instruments.
Keywords：VXI bus；DDS；PLL；PRECISE CLOCK