基于AD转换器的高精度电压测量电路的设计与实现
发布时间：2019-05-19 23:51
【摘要】：模数转换器是现代测量领域重要的电子器件。高精度模数转换器按照结构分类,通常包括逐次比较型、sigma-delt型、双斜或多斜积分型以及电压频率型。论文研究了一种新型积分过采样模数转换器,该种结构转换器具有较高线性度,千赫兹级信号带宽。它比通用集成模数转换器具有更高的精度性能,而比起常见的高精度专用模数转换器具有更高的采样率,其适用于电能计量仪器中,实现高精度电压测量。为了验证积分过采样理论的正确性以及该种结构转换器的可行性,论文设计了基于集成AD转换器的专用型电压测量或转换电路,其构成了积分过采样模数转换器。论文主要工作为:1.分析积分过采样模数转换器的电路结构与工作过程,对经典量化噪声与过采样理论进行研究,推导出积分过采样模数转换器的信噪比公式以及临界条件。2.分析积分过采样模数转换器的自校准设计方法,研究迭代自校准误差项、电荷注入误差项、集成ADC线性误差项的校准流程以及相应补偿方法。最后分析了补偿放电时间误差的两种方法,分别为量化放电法与直接测量法。3.研究模数转换器的测试理论。首先分析模数转换器测试需遵循的相干条件,然后分析了测量静态误差的直方图测试法以及测量动态精度的FFT测试法。最后使用matlab对模数转换器的线性误差、增益误差、失调误差建模,并对直方图测试法以及FFT测试法进行仿真验证。4.为验证积分过采样理论正确性与可行性,设计与实现18位积分过采样模数转换器。该转换器使用14位集成模数转换器积分过采样16倍,其具有双极性输入电压范围-2~+2 V,采样率10 kHz。5.搭建测试平台,对该18位积分过采样转换器进行测试。通过码密度测试,得到静态精度:最大DLE小于0.8 LSB,最大ILE小于4 LSB。通过FFT测试,得到动态精度:噪声和失真总和比为91.87 dB,信噪比为92.03 dB,总谐波失真比为-105.9 dB,无杂散动态范围为-107.3 dB,有效位数14.96。
[Abstract]:Analog-to-digital converter (ADC) is an important electronic device in the field of modern measurement. High precision analog-to-digital converters are classified according to structure, including successive comparison type, sigma- delt type, double oblique or multi-oblique integral type and voltage frequency type. In this paper, a new type of integral oversampling analog-to-digital converter is studied, which has high linearity and kilohertz signal bandwidth. Compared with the general integrated analog-to-digital converter, it has higher accuracy and higher sampling rate than the common high-precision special analog-to-digital converter. It is suitable for electric energy metering instruments to achieve high-precision voltage measurement. In order to verify the correctness of integral oversampling theory and the feasibility of this kind of structural converter, a special voltage measurement or conversion circuit based on integrated AD converter is designed in this paper, which constitutes an integral oversampling analog-to-digital converter. The main work of this paper is as follows: 1. The circuit structure and working process of integral oversampling analog-to-digital converter are analyzed, the classical quantitative noise and oversampling theory are studied, and the signal-to-noise ratio formula and critical condition of integral oversampling analog-to-digital converter are derived. 2. The self-calibration design method of integral oversampling analog-to-digital converter is analyzed, and the iterative self-calibration error term, charge injection error term, calibration flow of integrated ADC linear error term and corresponding compensation method are studied. Finally, two methods to compensate the discharge time error are analyzed, which are quantitative discharge method and direct measurement method. The test theory of analog-to-digital converter is studied. Firstly, the coherence conditions to be followed in the test of analog-to-digital converter are analyzed, and then the histogram test method for measuring static error and the FFT test method for measuring dynamic accuracy are analyzed. Finally, matlab is used to model the linear error, gain error and misalignment error of analog-to-digital converter, and the histogram test method and FFT test method are simulated and verified. 4. In order to verify the correctness and feasibility of integral oversampling theory, an 18-bit integral oversampling analog-to-digital converter is designed and implemented. The converter uses 14-bit integrated analog-to-digital converter to integrate oversampling 16 times. It has a bipolar input voltage range of-2 V and a sampling rate of 10 kHz.5.. The 18-bit integral oversampling converter is tested by building a test platform. Through the code density test, the static accuracy is obtained: the maximum DLE is less than 0.8 LSB, the maximum ILE is less than 4 LSB.. Through FFT test, the dynamic accuracy is as follows: the sum ratio of noise to distortion is 91.87 dB, the total harmonic distortion ratio is 92.03 dB, and the total harmonic distortion ratio is-105.9 dB,. The effective number of effective bits is-107.3 dB,.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN792
本文编号：2481173
[Abstract]:Analog-to-digital converter (ADC) is an important electronic device in the field of modern measurement. High precision analog-to-digital converters are classified according to structure, including successive comparison type, sigma- delt type, double oblique or multi-oblique integral type and voltage frequency type. In this paper, a new type of integral oversampling analog-to-digital converter is studied, which has high linearity and kilohertz signal bandwidth. Compared with the general integrated analog-to-digital converter, it has higher accuracy and higher sampling rate than the common high-precision special analog-to-digital converter. It is suitable for electric energy metering instruments to achieve high-precision voltage measurement. In order to verify the correctness of integral oversampling theory and the feasibility of this kind of structural converter, a special voltage measurement or conversion circuit based on integrated AD converter is designed in this paper, which constitutes an integral oversampling analog-to-digital converter. The main work of this paper is as follows: 1. The circuit structure and working process of integral oversampling analog-to-digital converter are analyzed, the classical quantitative noise and oversampling theory are studied, and the signal-to-noise ratio formula and critical condition of integral oversampling analog-to-digital converter are derived. 2. The self-calibration design method of integral oversampling analog-to-digital converter is analyzed, and the iterative self-calibration error term, charge injection error term, calibration flow of integrated ADC linear error term and corresponding compensation method are studied. Finally, two methods to compensate the discharge time error are analyzed, which are quantitative discharge method and direct measurement method. The test theory of analog-to-digital converter is studied. Firstly, the coherence conditions to be followed in the test of analog-to-digital converter are analyzed, and then the histogram test method for measuring static error and the FFT test method for measuring dynamic accuracy are analyzed. Finally, matlab is used to model the linear error, gain error and misalignment error of analog-to-digital converter, and the histogram test method and FFT test method are simulated and verified. 4. In order to verify the correctness and feasibility of integral oversampling theory, an 18-bit integral oversampling analog-to-digital converter is designed and implemented. The converter uses 14-bit integrated analog-to-digital converter to integrate oversampling 16 times. It has a bipolar input voltage range of-2 V and a sampling rate of 10 kHz.5.. The 18-bit integral oversampling converter is tested by building a test platform. Through the code density test, the static accuracy is obtained: the maximum DLE is less than 0.8 LSB, the maximum ILE is less than 4 LSB.. Through FFT test, the dynamic accuracy is as follows: the sum ratio of noise to distortion is 91.87 dB, the total harmonic distortion ratio is 92.03 dB, and the total harmonic distortion ratio is-105.9 dB,. The effective number of effective bits is-107.3 dB,.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN792
【参考文献】
相关硕士学位论文 前2条
1 郝新超;数字直流纳伏表关键技术研究[D];哈尔滨工业大学;2007年
2 任鸿;一种新型模拟积分器设计[D];吉林大学;2013年
，本文编号：2481173
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