一种测试高分辨率ADC 有效位数的新方法.doc

文档介绍：一种测试高分辨率ADC有效位数的新方法*
王慧刘正士徐亮陆益民
(合肥工业大学噪声与振动工程研究所, 合肥 230009)
摘要: 提出一种测试高分辨率A/D转换器(ADC)有效位数(ENOBs)的正弦拟合法, 和传统的正弦拟合法不同, 省去了严格选取参数初值的步骤, 避免了求解非线性方程组。该方法利用希尔伯特-黄变换(HHT), 从ADC输出数据中逐次拟合出基波曲线和谐波曲线的波形参数, 进而求得ENOBs。仿真结果表明, 在信号源频率高达1 MHz、分辨率分别取7~12位、所含二、三次谐波失真分别为-72 dB和-84 dB的情况下, 运用所述方法实现了对14位ADC的ENOBs的精确评价。
关键词: 高分辨率;A/D转换器;有效位数;希尔伯特-黄变换;正弦拟合;谐波失真
中图分类号: 文献标识码: A 国家标准学科分类代码:
New method for testing effective numbers of bits of high-resolution
analog-to-digital converter
Wang Hui Liu Zhengshi Xu Liang Lu Yimin
(Institute of Sound & Vibration Research, Hefei University of Technology, Hefei 230009, China)
Abstract: A new sine fitting method for testing the effective number of bits (ENOBs) of high-resolution analog-to-digital converter (ADC) is presented in this paper. Unlike conventional sine fitting method, this method leaves out the selection of initial value for the parameters and avoids to seek the nonlinear equations. On the basis of Hilbert-Huang transform (HHT), the parameters of fitting basic-wave and harmonic curves are obtained from ADC output data in turn, thereby the ENOBs are obtained. The simulation results show that, based on the method proposed in this paper, when a signal source is at the frequency of 1 MHz and under the circumstances of 7-12 bit resolution respectively, with both the 2nd harmonic distortion of -72 dB and the 3rd harmonic disto