Analog-Multiplier Circuit Linearizes Transducer Output

A circuit employing one operational amplifier and one analog multiplier is used to produce a voltage output proportional to the quantity t when the input voltage is related to t (e.g., temperature) by at + bt2, where a and b are constants. The determination of the resistor values, the useful operating voltage range, the accuracy of the linearizing process and the effects of changes in the ambient temperature are discussed. Extension of the circuit to higher order polynomial functions is also considered.     

A JFET Circuit for Instrumentation Applications

A new class of junction field-effect transistor (JFET) circuit is introduced, which can serve as a simple versatile building block in instrumentation applications. Economical realizations of current-to-voltage converters, voltage-controlled voltage sources, and voltage-controlled current sources are described. The basic circuit building block, called the piggy-back pair, consists of a matched pair of JFET's and two resistors. The basic configuration is easily manipulated to realize various circuit functions when combined with a few other components. It is shown that by full utilization of the terminal properties of JFET's, many simple high-performance circuits can be designed, which have circuit functions determined essentially by resistor ratios and which accordingly are relatively insensitive to device parameters. The circuit design procedure is very straightforward with design limitations clearly indicated. The flexibility and versatility of the piggy-back pair is indicated by the wide range of circuits demonstrated.     

一种电感式位移传感器的电路系统设计

介绍了一种电感式位移传感器的电路系统.该系统以一片AD698芯片为信号调整电路的核心,将位移量输出信号转换为相应的直流电压值,并结合其它一系列电路模块实现了测头位移量测量.通过对测头的标定试验证明该系统精度高、线性测量范围大.     

使用电流传感器的ACI／DCV转换电路

介绍一种使用电流传感器的交流电流－直流电压（ＡＣＩ／ＤＣＶ）转换电路，具有与被测电路隔离、体积小、测量范围广、线性度好等特点。     

1种热敏电阻温度传感器数字接口电路的研究

在一些用单片机组成的测试仪表或控制器中，常常需要一两路温度输入信号，如环境温度、水温的测量，而若仅为一两个温度信号的测量而增加1个硬件A／D转换器，则势必增加仪表的成本。这里所要介绍的热敏电阻温度传感器的数字接口电路，每路温度测量包括传感器在内仅10元左右的成本，在－20℃～＋70℃的测温范围内测温精度可达±0.2℃。并且性能稳定，抗干扰能力较强。已成功地应用在工业测控仪表中。     

电阻应变式测力传感器线性化电路的设计与分析

本文对电阻应变式测力传感器的非线性误差进行了具体的分析。提出了一种传感器线性化线路．理论分析和实验结果表明．该线性化线路对电阻直变式测力传感器的非线性误差具有良好的补偿作用。     

S波段宽带速调管输出回路的研究

给出了一种S波段宽带速调管,采用双间隙重叠模耦合腔展宽输出回路带宽,从等效电路出发计算其阻抗-频率曲线,并给出了测试结果。将设计的输出回路运用于整管研制中。热测结果表明,在250 MHz范围内,输出功率大于800 kW,满足整机设计要求。     

传输法模拟滤波器型输出回路的间隙阻抗频率特性

利用传输法把滤波器型输出回路等效为双端口微波网络问题,通过理论分析,数值模拟和冷测实验证明了S21平方后的曲线能定性反映滤波器型输出回路的间隙阻抗频率特性.从而在仿真设计阶段,可将S21设为优化目标,利用三维电磁仿真软件的参数优化功能实现精确设计滤波器结构,比相位法,场分析法更加快捷准确.传输法同样适用于矢量网络分析仪冷测滤波器的实验,可消除系统拆装及波导元件引起的误差,使测量更加方便准确.     

X波段三间隙耦合腔型输出回路间隙阻抗的模拟计算

本文基于理论分析和数值模拟,对一个X波段重叠模工作的三间隙耦合输出回路进行了分析计算.讨论了总间隙阻抗与群时延之间的关系以及回路的群时延对总间隙阻抗的影响.通过合理优化群时延曲线,该X波段三间隙耦合输出腔在三模重叠的情况下获得了1dB输出带宽大于14.5%(约1.3GHz)的结果.     

Current-Mode Capacitive Sensor Interface Circuit With Single-Ended to Differential Output Capability

This paper presents a current-mode interface circuit for capacitive sensors, with the main features being its ability to produce a differential output from a single-ended sensor (using a fixed reference capacitor) and its simplicity in realization. These advantages make it a potential candidate for applications where differential sensors are not available and where a simple design is required. The principle is, however, easily applicable to differential sensors as well. The interface concept can be realized in different ways; however, to present a proof of concept on silicon, a prototype has been fabricated and tested in a commercially available 0.8-mum CMOS process. The circuit has been designed using common analog building blocks such as a fully differential operational transconductance amplifier (OTA), a high-output-resistance wide-swing current source, and a single clock phase. The estimated linearity error was 0.2% relative to full-scale swing with a simple two-point calibration. The circuit consumes 145 muA from a 5-V power supply.     

三间隙耦合输出回路间隙阻抗频率特性的测量

从多端口微波网络等效的角度,讨论多间隙耦合输出回路间隙阻抗频率特性的测试问题,并以X波段三间隙耦合输出回路为例,分别从模拟测量和实际测量两个方面确定了其间隙耦合阻抗的频率特性,简化了测量过程,为三间隙耦合输出电路工程应用提供了有效的实验手段.     

Ultrasonic Transducer Sensitivity and Model-Based Transducer Characterization

It is shown that the role that an ultrasonic piezoelectric transducer plays in both generating and receiving ultrasound in an ultrasonic nondestructive evaluation (NDE) measurement system can be completely described in terms of the transducer's electrical impedance and open-circuit, blocked force receiving sensitivity. Furthermore, it is shown that both of these quantities can be obtained experimentally via a model-based approach and purely electrical measurements. The measurement of sensitivity uses a method originally developed for lower-frequency acoustic transducers. However, it is shown that at the higher frequencies found in ultrasonic NDE applications electrical cabling effects play an important role and must be compensated for in determining the transducer sensitivity. Examples of experimental measurement results using these new approaches are given.     

Ultrasonic Transducer Sensitivity and Model-Based Transducer Characterization

Abstract

It is shown that the role that an ultrasonic piezoelectric transducer plays in both generating and receiving ultrasound in an ultrasonic nondestructive evaluation (NDE) measurement system can be completely described in terms of the transducer's electrical impedance and open-circuit, blocked force receiving sensitivity. Furthermore, it is shown that both of these quantities can be obtained experimentally via a model-based approach and purely electrical measurements. The measurement of sensitivity uses a method originally developed for lower-frequency acoustic transducers. However, it is shown that at the higher frequencies found in ultrasonic NDE applications electrical cabling effects play an important role and must be compensated for in determining the transducer sensitivity. Examples of experimental measurement results using these new approaches are given.     

Ultrasonic Transducer Sensitivity and Model-Based Transducer Characterization

It is shown that the role that an ultrasonic piezoelectric transducer plays in both generating and receiving ultrasound in an ultrasonic nondestructive evaluation (NDE) measurement system can be completely described in terms of the transducer's electrical impedance and open-circuit, blocked force receiving sensitivity. Furthermore, it is shown that both of these quantities can be obtained experimentally via a model-based approach and purely electrical measurements. The measurement of sensitivity uses a method originally developed for lower-frequency acoustic transducers. However, it is shown that at the higher frequencies found in ultrasonic NDE applications electrical cabling effects play an important role and must be compensated for in determining the transducer sensitivity. Examples of experimental measurement results using these new approaches are given.     

音响功放开关电源输出功率检测电路的设计与实现

为了使开关电源很好地应用于音响功放,设计了一种开关电源输出功率检测电路,给出了电路的原理和具体实现方法.经测试证明该电路具有检测准确、动态性能良好的特点.     

Pressure Transducer Hysteresis Modeling

The paper describes the results of attempts to model hysteresis effects of strain gauge pressure transducers. Experimental data are presented with an analysis of the observed behavior and a model suitable for the transducer tested.     

速调管圆柱同轴谐振腔高阶TM310模式输出回路

设计了工作于高阶横磁TM310模式圆柱同轴谐振腔.模拟计算了六个漂移管间隙中心轴向谐振电场极大值位置处的特性阻抗.对于谐振腔加载空矩形波导和加载电感膜片滤波器矩形波导两种速调管输出回路,由微波电路理论和高频电磁场软件分别模拟计算了漂移管间隙中心的平均间隙阻抗和输出带宽.两种情形间隙阻抗的最大值分别为48.757 kΩ和14.328 kΩ;间隙阻抗的3dB带宽分别约为1.1MHz和2.8 MHz.研究表明,单间隙圆柱同轴输出腔高阶横磁TM310模式结构适用于高频、窄带和高功率多注速调管输出回路.     

Transducer of time to amplitude

Measurement Techniques -