A Single-Axis Low-Cost Accelerometer Fabricated Using Printed-Circuit-Board Techniques

This letter presents a new single-axis low-cost printed-circuit-board (PCB)-based accelerometer. Motivated by the need to develop low-cost human-sensing accelerometer, a capacitive PCB-based microelectromechanical-system (MEMS) accelerometer is developed, and the experimental results of the prototype have demonstrated that the objective is feasible. The PCB-based MEMS accelerometer is fabricated with a metal film adhered to a PCB, which forms the two electrodes of the sensing capacitor of the accelerometer. This signal is compared with the output signal of a commercially available accelerometer, ADXL330, by Analog Devices. The prototypes are designed to have a dynamic range of $pm$5 g and a bandwidth from 0 to 20 Hz, which covers the range of accelerations for human limbs. The result shows that the new low-cost accelerometer can fulfill the requirement of human motion sensing.      

An Internally-Matched High-Isolation CMOS SPDT Switch Using Leakage Cancellation Technique

An internally-matched single-pole double-throw (SPDT) switch with high isolation is presented. The high isolation is resulted from the leakage cancellation by employing a compensation circuit, which also achieves impedance match for all ports. The SPDT chip, implemented in a 0.18-mum CMOS process, achieves a measured isolation of 72 dB, an insertion loss of 1.1 dB, return losses better than 10 dB at all ports and PidB of 19.3 dBm at 1.9 GHz.     

高精度加速度计信号变换技术

针对捷联惯导系统加速度计信号采集的高精度要求,提出了一种采用I-F变换技术对加速度计进行高精度数据采集的方法,对其工作原理、构成及提高精度的方法等问题进行了分析和讨论。实验证明,该系统满足了捷联惯导系统的精度要求,具有普遍的实用价值。     

开关电源IC的绿色设计

由于对电器及电子产品的环保要求越来越高,迫使人们不得不思考如何规划产品“绿化”工程及打造绿色产业链等问题,而绿色设计是绿色产业链中重要和首要的环节。文中就绿色产业链的主要组成环节及开关电源IC绿色设计应该解决的主要问题及其必要性进行了讨论,提出低待机功耗、功率因数校正(PFC)、电磁兼容(EMC)及强大的保护等功能已成为全球半导体业界共同关注的课题,并提出了与用户紧密结合,在系统层面上进行绿色设计的重要性。     

基于CY7C68013A芯片的USB键盘的设计

由于具备传输速率高、体积小等特点,USB接口广泛地应用于计算机外部硬件设计。针对此介绍了Cypress公司的CY7C68013A芯片的基本原理,以及使用CY7C68013A芯片进行USB键盘设计的方法。     

Optimization Design of Silicon Micro—capacitive Accelerometer with PWM Technique

The property of silicon micro-capacitive accelerometer is analyzed and discussed by establishing the model of the sensor,to lay a basis for optimization design of sensor system structure.Discussed issues include the static modeling and dynamic behavior of the two commnly used structures,i.e.,double-cantilever supported and four-beam supported structures,and also the measurement range of these devices.     

一种结构新颖的地震动加速度计

对比典型的差动电容结构,设计了一种新的折叠梁电容式MEMS低g(g=9.8m/s~2,当地重力加速度)值加速度计,指标为量程0～±2g,横向灵敏度<3%。利用有限元分析软件对模型进行了静态应力分析和模态分析,并给出了接口电路和自检测功能原理。最后设计了一套可行的加工工艺。     

一种基于开关门阵列结构的9级TDI读出电路

介绍了一种采用开关门阵列结构实现的9级TDI功能的读出电路.片中包含了脉冲发生电路.测试结果表明,该电路能够实现9级积分功能,电荷处理能力为11.9 pC,电压输出摆幅为3.1 V,最小可积分电流为0.1 nA.     

FA5310开关电源控制IC及其应用

介绍了FA5310开关电源控制IC的性能、特点及工作原理，并给出了它的一种具体应用电路。     

性能卓越,绿色环保——瑞萨电子uPG/uPD系列天线开关产品

在线座谈(Online Seminar)是中电网于2000年推出的创新服务,通过"视频演示+专家解说+在线问答"三位一体相结合的形式,充分发挥网络平台的便捷性,实现了先进半导体技术提供商与系统设计工程师的实时互动交流,其形式和内容都广受电子行业工程师的好评。本刊每期将挑选一些精华内容整理成文,以飨读者。欲了解更多、更详细的内容,敬请登录http://seminar.eccn.com。     

A Sign-Component-Based Framework for Chinese Sign Language Recognition Using Accelerometer and sEMG Data

Identification of constituent components of each sign gesture can be beneficial to the improved performance of sign language recognition (SLR), especially for large-vocabulary SLR systems. Aiming at developing such a system using portable accelerometer (ACC) and surface electromyographic (sEMG) sensors, we propose a framework for automatic Chinese SLR at the component level. In the proposed framework, data segmentation, as an important preprocessing operation, is performed to divide a continuous sign language sentence into subword segments. Based on the features extracted from ACC and sEMG data, three basic components of sign subwords, namely the hand shape, orientation, and movement, are further modeled and the corresponding component classifiers are learned. At the decision level, a sequence of subwords can be recognized by fusing the likelihoods at the component level. The overall classification accuracy of 96.5% for a vocabulary of 120 signs and 86.7% for 200 sentences demonstrate the feasibility of interpreting sign components from ACC and sEMG data and clearly show the superior recognition performance of the proposed method when compared with the previous SLR method at the subword level. The proposed method seems promising for implementing large-vocabulary portable SLR systems.     

A Novel Integrated CMOS Switch Circuit for High Precision Sample-and-Hold Technique

A new CMOS switch circuit is proposed for the implementationof high precision sample-and-hold. The switch includes a currentmirror and switching action is controlled by current pulses.This reduces charge injection due to clock feedthrough and thecharge injection is input signal independent, resulting in agreatly improved sample-and-hold accuracy.     

基于扫描的集成电路故障诊断技术

随着集成电路技术的飞速发展,人们对集成电路产品的可靠性要求越来越高,这就要求集成电路测试特别是故障诊断提出了更高的要求.基于扫描的故障诊断方法是广泛应用的故障诊断方法之一.介绍基于扫描的集成电路故障诊断方法,并详细介绍了一种改进的扫描诊断方法和一种基于扫描的全速诊断方法.     

基于加速度传感器的油井示功图位移测量技术研究

示功图是分析油田抽油机与抽油杆工作状态的重要手段,本文针对采油现场示功仪小型化和无绳化的趋势,提出了一种基于加速度传感器的油井示功图位移测量方案.介绍了加速度信号的检测、调理等硬件电路设计和位移计算方法;为提高加速度信号的测量精度,提出了一种复合滤波方法,并完成了MSP430单片机的编程实现.现场试验表明,基于加速度测量所得到的位移和冲程的计算结果完全满足现场示功图测量的精度要求.     

MEMS开关技术的研究与进展

开关是信号变为现实.在MEMS技术的基础上,分析了MEMS开关技术及其在电路系统中的应用,并着重阐述了射频MEMS的结构及其相关技术特点.     

开关电源噪声的抑制技术

通过对开头电源噪声种类及产生机理的分析,提出了抑制噪声的几种方法。     

一种改进型除法集成电路的设计

介绍了一种改进的除法集成电路,该电路适合于对精度要求很高、而对速度要求不高的应用场合。它对原有的除法实现算法做了调整,减小了运算误差,同时减少了所需的器件数量,从而缩小了芯片面积。     

一种采用厚膜混合工艺的10位高速D/A转换器

介绍了一种采用厚膜混合集成工艺制作的倒R-2R电阻网络结构的高速10位D/A转换器电路.重点分析了二极管电流开关对输出电流建立时间的影响,提出了一种改进型二极管电流开关结构,减少了二极管电流开关中电荷泄放引起的过冲,使电流建立时间大大减小,样品电路测试典型值为25 ns.     

CMOS多路加权SAW滤波器高频模拟开关研究

报道了0.6μm CMOS 4路可编程加权高频模拟开关集成电路,其开关和加权功能分别由两个高跨导的N沟MOS晶体管实现。模拟开关连续可调的动态加权范围最大为21.3 dB,最小插入损耗约为-6 dB。在线功能测试表明,该集成电路可对中心频率在50~250 MHz范围内的声表面波(SAW)滤波器进行取样、加权、可编程加权叠加,可应用于多芯片模式组成的可编程声表面波滤波器。     

A 50 to 94-GHz CMOS SPDT Switch Using Traveling-Wave Concept

A fully integrated single-pole-double-throw transmit/receive switch has been designed and fabricated in standard bulk 90-nm complementary metal-oxide semiconductor (CMOS) technology. Traveling wave concept was used to minimize the insertion loss at higher frequency and widen the operating bandwidth. The switch exhibits a measured insertion loss of 2.7 -dB, an input 1-dB compression point (input P_{1 dB}) of 15 dBm, and a 29-dB isolation at the center frequency of 77 GHz. The total chip size is only 0.57 times 0.42 mm ² including all testing pads. To our knowledge, this is the first CMOS switch demonstrated beyond 50 GHz, and the performances rival those monolithic microwave integrated circuit switches using standard GaAs PHEMTs