【作者】 付震； 胡善清； 李兴明； 贲蓉蓉；

【Author】 FU Zhen;HU Shanqing;LI Xingming;BEN Rongrong;Beijing Key Laboratory of Embedded Real-time Information Processing Technology,Beijing Institute of Technology;Tsinghua University;

【机构】 北京理工大学嵌入式实时信息处理技术北京市重点实验室； 清华大学电子系；

【摘要】 随着高速实时信号处理技术的发展,高速实时信号处理系统的数据处理能力越来越高,也对系统中的数据采集部分提出了更高要求,而作为系统数据获取关键部分的ADC芯片,也在顺应需求往高输入带宽、高采样速率、高量化精度方向发展。目前,高性能ADC的采样率普遍跨入Gsps采样率的量级,其性能指标极易受除ADC芯片本身性能以外的因素影响,如时钟、电源、模拟前端等外围设计。在实际设计中,时钟和电源可以通过选用更高性能的时钟和电源芯片提升各自性能,然而前端链路的设计大多依赖经验法则,容易造成设计的返工及多次迭代。从信号完整性角度分析了前端链路的阻抗不连续对高速信号的影响,提出了一种综合考虑SMA连接器和阻容网络的前端链路优化方法,并通过全链路建模仿真对优化效果进行了验证。结果表明,通过该方法优化后的链路设计明显改善了前端链路的S参数指标。更多还原

【Abstract】 With the development of high-speed real-time signal processing technology,high-speed real-time signal processing system of data processing ability is getting higher and higher,which puts forward higher requirements on data acquisition part of the system.Thus,as the key part of data acquisition system,ADC’s development is also heading to the high input bandwidth,high sampling rate and high accuracy of quantitative direction.At present,high performance ADC’s sampling rate is generally entered the Gsps magnitude,which means its performance is affected by factors other than the performance of the ADC chip itself,such as clock,power supply,the design of analog front end and other peripheral.In actual design,clock and power can improve their performance by choosing power supply chips and clock chips with better performance.However,the design of the front end link most depends on the rule of thumb,which makes it easy to cause design rework and multiple iterations.From the point of view of signal integrity,this paper analyzes influence on high speed signal by impedance discontinuity of the front-end.This paper proposes an optimization method of front end comprehensively considering both SMA connector and resistance capacity network,and this optimization method is verified through the whole link modeling simulation optimization results.Results show that the method of optimized link design significantly improves the S parameters of the front end link.更多还原