基于新型专用运放的现代传感器调理电路设计

越来越多地选用新型专用运放设计现代传感器调理电路,将成为必然趋势。结合现代传感器调理电路设计中的若干重要技术问题,重点讨论了全差分运放、带EMI/RFI滤波器的仪表放大器、带远程负载检测的仪表放大器、单电源微功耗仪表放大器、静电计级运放等新型专用运放,在现代传感器调理电路设计中的具体应用。表明选用合适新型专用运放设计现代传感器调理电路,可以解决选用常用运放难以解决的问题或得到更高的性能。相关的设计思想与设计技术,也适用于其他类似应用实践。     

运用负反馈模型分析实际运算放大器电路

对工作在深度负反馈状态的运算放大器电路,常采用虚短虚断技术得出的理想参数代替实际参数。这种方法忽略了理想模型与实际电路之间的误差。为了知道这个误差给实际运算放大器电路带来的影响,通过将运算放大器电路等效成对应的负反馈系统模型,并计算反馈系数,运用该模型的等效参数来更加近似的分析实际运算放大器电路闭环参数及其稳定性。     

含运算放大器电路的图解分析

运算放大器在工作时具有两种状态:线性状态和非线性状态,分别对应其输入—输出特性的线性区和正、负饱和区。本文采用图解分析法讨论了含运算放大器电路的解及其解的特性,指出含运算放大器电路如采用负反馈接法,则其解唯一且稳定;如采用正反馈接法,则其稳定工作状态必为非线性状态。对教学中加入含运算放大器电路接法的教学内容,本文给出一些教学建议。     

基于闭环集成运放的模拟电路模块级软故障诊断

基于斜率故障模型,提出了一种诊断模拟电路中基于闭环集成运算放大器的模块级软故障的字典法.在由闭环运放组成的模拟电路中,通过对电路以闭环运放及与其输入直接相连的元件看作一个整体划分模块,对各个模块中的任一元件或进行宏模型替代之后的运放等效电路,利用电路中的两节点电压增量计算出的斜率作为统一故障特征,建立故障字典,实现电路中相应模块包含的运放和所有元件的软故障诊断.给出了运放的等效宏模型和模块级软故障的诊断步骤,并用仿真实例证明了该诊断方法的有效性.     

Reduction of EMI Susceptibility in CMOS Bandgap Reference Circuits

This paper presents a successful approach to increase the electromagnetic interference (EMI) immunity of CMOS bandgap reference circuits. Layout techniques along with some changes in the reference schematics lead to a robust electromagnetic immunity, preserving good overall performances. Measurement results confirm the low susceptibility of the proposed circuits. They exhibit only a few millivolts shift, for interfering signals of 1 Vpp in the frequency range of 1 MHz to 4 GHz, compared to the classical topologies that may reach more than 1 V. The circuits were fabricated in a 0.8-mum standard CMOS technology     

测控电路设计中运算放大器的若干误用

运算放大器(运放)在测控电路中有重要而广泛的应用,已成为测控电路中的基本器件.测控电路的特点对运放的应用设计有更高的要求.在测控电路设计中,往往因运放的应用设计不当或错误而降低电路的性能,甚至电路不能正常工作.总结了在测控电路设计中运放的几种重要误用,分析了其原因,并给出了相应的对策.相关的讨论与结论对运放在测控电路中的应用设计具有参考作用.     

Model for Transient Fault Susceptibility of Combinational Circuits

Transient faults (TFs) are increasingly affecting microelectronic devices as their size decreases. During the design phase, the robustness of circuits for high reliability applications with respect to this kind of faults is generally validated through simulations. However, traditional electrical level simulators are too slow for the task of simulating the effects of TFs on large circuits. In this paper, we present a new model to estimate accurately the possible propagation of transient fault-due glitches through a CMOS combinational circuit. We will show how the proposed model can be applied in order to estimate the TF susceptibility of a circuit by simply considering the propagation delay of the datapath. Therefore, the proposed model is suitable to be used into a new simulation tool able to provide good accuracy, while significantly speeding up simulations, with respect to electrical level simulation. In particular, our model allows approximately 90% accuracy with respect to HSPICE simulations.     

Modified Model for Settling Behavior of Operational Amplifiers in Nanoscale CMOS

An accurate time-domain model for the settling behavior of folded-cascode operational amplifiers is presented. Using a velocity–saturation model for MOS transistors makes the proposed model suitable for nanoscale CMOS technologies. Both linear and nonlinear settling regimes and their combination are considered. Transistor-level HSPICE simulation results of a fully differential single-stage folded-cascode amplifier using BSIM4v3 models of a standard 90-nm CMOS process are presented to verify the accuracy of the proposed models.      

影响集成运放输入误差信号的主要参数分析

正确使用集成运算放大器必须了解影响其工作性能的主要，其中输入误差信号是影响运放工作性能的重要参数之一。本文主要研究引起集成运放输入误差信号的主要参数及减小其影响的方法。     

基于可编程跨导运算放大器POTA低通有源滤波器设计

该文给出了基于可编程跨导运算放大器(POTA)的有源滤波器设计方法,能在一定范围内实现跨导值程控调节, 提高调节精度和准确度。并且利用Jacobi法求解相似对角形矩阵,避免解高次方程的难题。所设计的有源滤波电路不易受分布电容的影响,稳定性好、灵敏度低。本文给出了设计实例,显示了该方法的优点。     

基于矢量水听器的信号调理电路设计研究

矢量水听器可以有效地获取水下的声信号,并将其转化成可以进行处理的电信号,但是此信号十分微弱,并且掺杂着水中复杂的噪声,为了有效实现信号处理,设计了信号调理电路,分为电源模块、放大模块和滤波模块,可以提高输出信号的信噪比。通过对电路进行仿真以及测试实验,验证了设计的有效性。     

Functional Properties and Frequency Characteristics of Low-Sensitive RC Filters Based on Micropower Operational Amplifiers

Russian Microelectronics - The main designs of low-sensitivity multiloop active RC filters (ARCFs) based on micropower operational amplifiers (OAs) for preliminary sensor signal processing in...     

基于运算放大器正向积分电路的初步研究

在自控系统中,常用积分和微分电路作为调节环节,以集成运放作为放大电路,利用电阻和电容作为反馈网络,可以实现这两种运算电路.针对常规的运算放大器反向积分电路的算法,提出了一种基于运算放大器正向积分电路的算法,并通过数学上的推导说明了正向积分屯路的工作原理,最后对推导的结论进行了仿真和验证.通过仿真和验证可知:正向积分电路的输出电压与输入电压是同方向的,另外正向积分运放电路只需要单电源供电且其积分速率为常规反向积分电路的两倍.     

基于电容式微加速度计的信号调理电路的设计与标定

为了提高MENS微加速度计的各种性能,完成了基于电容式微加速度计的过载传感器信号调理电路的设计。设计了基于Model 1221电容式微加速度计的信号调理电路,通过静态和动态调试,在频率响应范围内的带内不平度≤±3 dB,超出频率响应范围的带外衰减≥30 dB/oct。最后通过传感器主动校准系统对传感器进行标定测试,测试结果显示:理论值与实际值的误差很小,系统的准确度很高,而且在±15 gn的测量范围内的输出电压满足(0.2±0.2)V^4.8±0.2V。     

Numerical Spectral Model Based on BPM for Er-doped Waveguide Amplifiers

A spectral numerical analysis method to analyze the Er-doped waveguide amplifiers（EDWA） in wavelength division multiplexing is presented. This model is based on finite difference beam propagation method modified by Douglas scheme, which can efficiently reduce the truncation error and time consumption. By superposing the Lorentzian function for the experimental curves, the spectral properties of EDWA can be investigated. Results show that the pump efficiency of EDWA pumped at 980 nm is higher than that at 1 480 nm. Meanwhile, by rationally increasing the pump length and the erbium concentration, larger signal gains can be acquired. Taking account of the up-conversion and cross-relaxation effects of cooperation, the spectrum analysis of highly doped EDWA is carried out over a wider frequency band.     

Predicting the Effect of Pulsed Ionizing Radiation on Operational Amplifiers

The response of IC operational amplifiers (op amps) to pulsed ionizing irradiation is studied theoretically and experimentally. The major mechanisms of the radiation response are covered. The contributions of main op-amp stages to the output-voltage response are analyzed. The ionization-induced failure of an op amp is traced to its intermediate stages. It is established that the recovery time depends on the type of compensation employed. A block-model approach is proposed as a method for the prediction of transient radiation responses. Ways to define the performance index of an op amp exposed to pulsed ionizing radiation are discussed.     

基于互感模型的混合封装电力电子集成模块内 电磁干扰的研究

研究了大电流混合封装电力电子集成模块(IPEM)内功率电路对控制驱动电路的电磁干扰问题研究表明,功率电路的内部环流通过互感耦合的方式会对IPEM内部的控制和驱动电路产生重要影响,特别是环流的高频分量为了对环流的EMI进行评估,建立了IPEM的内部环流实验模型另外,一种简化的基于局部元等效电路(PEEC)原理的建模和计算方法被用于计算环流回路与控制和驱动回路之间的互感,实验证明结果是比较准确的.     

Computer-Aided Analysis of RFI Effects in Operational Amplifiers

The modified Ebers-Moll model is used to predict RFI effects in the 741 operational amplifier (op amp)-a bipolar linear integrated circuit (IC). RFI susceptibility predictions for RF incident upon the op-amp input terminals are made using a complete model, a macromodel, and a voltage-offset model. Both the batch-mode computer program SPICE 2 and the commercial interactive computer program ISPICE are used. The three sets of calculated results are essentially identical and agree within 4 dB with experimental results measured at 220 MHz. A threshold cannot be given for the RF power level at which a 741 op amp is susceptible to RFI. The level depends upon the op-amp circuit application. For op-amp circuits designed to amplify input signals in the 0.1-to 1.0-V range, RF power levels as large as -15 to + 5 dBm may be required to cause RHI susceptibility problems. For op-amp circuits designed to amplify input signals in the 1-to 10-mV range, RF power levels as low as -55 to -35 dBm may cause RHI susceptibility problems.     

模拟运算电路运算误差分析

模拟运算电路在测控领域有广泛应用。运算误差是评价运算电路性能的重要指标之一。确定影响运算误差的主要因素和估算运算误差的大小,对指导运算电路设计和评价运算电路性能,都是必要的。文章探讨了引起模拟运算电路运算误差的几种主要因素,给出了它们引起的运算误差的估算方法,讨论了在模拟运算电路设计中减小运算误差的相应措施。结论可用于指导模拟运算电路设计和运算误差评价。     

智能仪器课程教学中的运算放大器

本文总结了主流运算放大器尤其是程控增益放大器、仪用放大器和隔离放大器的主要特点,包括型号、增益范围、增益编程或设置方式及主要生产厂家等,通过对这些特点的教学或学习,帮助学生了解有关器件的主要类型、特征,为有关教学和应用提供有价值的参考。