《专用集成电路设计》教学方法初探

《专用摹成电路设计》是本科电气信息类专业的一门重要专业课。该文探讨了非微电子专业《专用集成电路设计》课程的教学方法。结合教学实践,总结了讲授《专用集成电路设计》课的几点体会。     

Analysis,modeling, and design of cascaded defected microstrip structure for planar circuits

In this article, two cascaded defected microstrip structures (CDMSs) are proposed to increase the effective inductance. So the cutoff frequencies of filters made by CDMSs can be controlled. The proposed CDMSs have wider stopband characteristic and sharper transition from passband to stopband than defected microstrip structure (DMS). To show the behavior variations of the effective inductance, the DMS and CDMSs have been analyzed, compared, and their design parameters are formulated. These parameters are necessary for a fast filter design procedure. Also, the models of DMS and CDMSs using the very simple lumped element forms are presented according to the physical parameters. The results of the proposed models have been compared with those obtained by full wave analysis. To verify the proposed DMS model, the comparison in response not only has been considered in amplitude but also in phase of all S‐parameters of proposed model and full wave analysis. It is obvious that the stopband is enhanced by periodically cascading the DMS. Surviving of EMC aspects between DMS, DGS, and CDMS is considered and compared. Finally, the theoretical results are validated by comparison with simulations of the structures and experimental results. The simulations from modeling results are found to be in good agreement with the full wave analysis and measurement results in the range of 0.5–35 GHz. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010.     

一种新型矿用本质安全型电源的设计

针对目前煤矿井下多输入电压等级本质安全型电源的笨重和单输入电压等级本质安全型电源的局限性问题,提出了一种新型本质安全型电源的设计方案。该新型本质安全型电源采用R型隔离变压器,体积小;采用高性能的DC/DC开关转换电源,提高了本质安全型电源的转换效率,且减小了输出纹波噪声;同时采用由过流检测芯片、单稳态触发芯片、大功率三极管等组成的双重化过流和过压保护电路,提高了本质安全型电源的可靠性。     

稀疏贝叶斯相关向量机的模拟电路故障诊断

模拟电路故障诊断受制于传统的机器学习方法需要人为设定参数,分类效果依赖于参数设定是否成功,无法进行在线诊断。为此,提出一种基于稀疏贝叶斯相关向量机理论的模拟电路故障诊断模型,改进权值更新算法,设定阈值提前剔除非相关权值,减少算法运行时间,加快权值更新速度。在贝叶斯框架下对分类函数的权重进行推断,并得到各分类的后验概率,从而判断分类结果的置信度,辅助诊断决策。仿真结果表明,与支持向量机相比,该模型在精度相当的情况下,需要的相关向量更少,更具稀疏性和泛化性,分类时效性更高,适合模拟电路的在线检测。     

Thin-film electrode based droplet detection for microfluidic systems

We report on a droplet-producing microfluidic system with electrical impedance-based detection. The microfluidic devices are made of polydimethylsiloxane (PDMS) and glass with thin film electrodes connected to an impedance-monitoring circuit. Immiscible fluids containing the hydrophobic and hydrophilic phases are injected with syringe pumps and spontaneously break into water-in-oil droplet trains. When a droplet passes between a pair of electrodes in a medium having different electrical conductivity, the resulting impedance change signals the presence of the particle for closed-loop feedback during processing. The circuit produces a digital pulse for input into a computer control system. The droplet detector allows estimation of a droplet's arrival time at the microfluidic chip outlet for dispensing applications. Droplet detection is required in applications that count, sort, and direct microfluidic droplets. Because of their low cost and simplicity, microelectrode-based droplet detection techniques should find applications in digital microfluidics and in three-dimensional printing technology for rapid prototyping and biotechnology.     

基于虚拟仪器文氏桥混沌电路的建模与仿真

为缩短混沌电路的研究周期,提出了一种利用虚拟仪器实现混沌电路的方法。采用改进型欧拉算法对文氏桥混沌电路的状态方程进行近似处理,建立了相应的离散模型。在虚拟仪器(Labview)环境下进行数值仿真,可观察到在电路参数变化时电路动力学行为的演变过程,并通过构建采集系统,实现了文氏桥混沌电路离散模型的混沌信号输出。仿真结果与已有研究结果完全一致,有效地体现了"软件既是仪器"的概念。     

发动机嵌入式传感器自主供电装置

通过热电形式,发动机内部的废热可以为嵌入式传感器提供工作所需要的电能。根据温差发电原理设计了一种能够利用发动机内部存在的温度差为嵌入式传感器供电的装置。它由集热板、隔热层、散热装置以及相应的电源管理电路组成。在负载与发电器件内阻匹配和最低温度差为10℃的条件下,电源管理电路能够将发电器件输出的0.52 V电压转化为5.06 V、4.57 mA的稳定输出。建立了实验模型,且通过实验进行了性能验证。     

基于CAN总线电子系统在车辆底盘控制中的应用

对于军用特种车辆底盘控制系统使用的点对点控制方式所造成的车体底盘布线复杂、布局不合理、维修更换难等一系列技术问题进行了分析研究.设计了基于CAN总线的电子综合控制系统,各测控模块进行多点控制,同时各测控模块采用基板印制电路板加功能印制电路板的组合,可随时根据现场车体被控设备的要求进行添加或精简,各测控模块通过CAN总线...     

PCB检测中图像分割技术研究

光学检测是进行印刷电路板(PCB)装配质量检验的重要手段,应用图像分割技术可以提取PCB中的目标物以进行检测。针对PCB图像分割,提出一种基于改进量子遗传算法的图像分割方法。该方法将基于阈值的图像分割方法转化为阈值优化问题,通过改进量子遗传算法的计算实现最优图像分割阈值的求取。仿真结果验证了该方法的可行性。     

Fast problem-size-independent parallel prefix circuits

A family of parallel algorithms solving the prefix problem on the combinational circuit model is presented. These prefix circuits are waist-size optimal with waist 1 (WSO-1). They are not only building blocks for constructing fast depth-size optimal prefix circuits, but also themselves fast problem-size-independent prefix circuits. When the problem size is greater than the circuit width, the presented prefix circuits may very much faster than any other prefix circuits of the same width, especially when the problem size is greater than or equal to twice the circuit width. The new prefix circuits are compared analytically with other representative prefix circuits to show how fast they are. They have the minimum depth and are the fastest among all WSO-1 prefix circuits of the same width and fan-out. Thus, they are better building blocks than other WSO-1 circuits for constructing fast depth-size optimal prefix circuits with the same fan-out.