智能温度传感芯片中Δ-Σ调制器的设计  

Design of Δ-Σ modulator in smart temperature sensor chip

作　　者：严琴[1] 

机构地区：[1]厦门大学嘉庚学院机电系,福建厦门361005

出　　处：《电子技术应用》2011年第2期39-41,45,共4页Application of Electronic Technique

摘　　要：从模数转换的基本理论出发,在对一阶Δ-Σ调制器原理深入解析的基础上,得到Δ-ΣADC动态输入范围的计算方法。利用Matlab simulink建立了二阶Δ-Σ调制器系统模型,对调制器电路进行仿真和参数优化,对其性能进行了有效评估。使用轨对轨折叠式共源共栅运算放大器作为调制器的积分器,增大了调制器的动态输入范围;设计的高速比较器将NMOS负载管交叉耦合从放大器输出端引入正反馈,提高了转换速度。设计实现了一款适用于14 bit温度转换芯片的二阶△-∑调制器,信噪比SNR可达87 dB。From the basic theory of analog-digital conversion, on the basis understanding the principle of 1st order △-∑ ADC,calculate the dynamic input range of △-∑ ADC modulator,study the 2nd order △-∑ ADC modeling through simulink,then simulate and design parameters of the modulator,last make an effective performance evaluation. Use rail-to-rail folded-cascode op Amp, increase the dynamic input range of modulators; Based on the positive feedback gain improved principle, design high-speed comparators, greatly improving the conversion speed. Design and impement a second order △-∑ modulator for the 14 bit temperature conversion chip, the SNR is 87dB.

关 键 词：△-∑调制器 Matlab建模 轨对轨 

分 类 号：TN761.91[电子电信—电路与系统]