一种霍尔电流传感器的电路设计

为了解决霍尔电流传感器电流动态测试范围小、线性度低及频带宽度不能满足实际工程需求的问题.设计出了零磁通型霍尔电流传感器,利用零磁通原理,通过检测二次线圈的电流(反馈电流),计算一次侧电流(被测电流)的大小.采用REF232电压基准芯片为HW300B型霍尔元件提供工作电流,采用仪器放大器AD620对霍尔元件产生的霍尔电压进行放大.通过测试表明,该传感器的电流动态测试范围比同类型的传感器提高了50%,线性度可以达到输入电流的0.2%,频带宽度可以达到300 kHz.     

霍尔元件的几种检测方法

霍尔元件为磁敏元件,体积小,多为四脚元件,分卧式和立式两种。如原机用卧式霍尔元件,代用进也需用卧式霍尔元件,反之亦然。不过在位置允许的情况下也可用任何型号的卧式或立式霍尔元件代用。霍尔元件是利用霍尔效应制成的新型磁敏元件,它由霍尔传感头,放大器、温度补偿电路及稳压电路构成。能感应与磁有关的物理量,并能输出相应电信号,具有体积小,灵敏度     

差分霍尔效应加速度测量方法及其线性实验模拟

对磁场中对称结构的霍尔元件的输出特性进行研究,提出一种差分霍尔效应加速度测量方法。基于线性霍尔元件和圆柱形永磁体设计加速度测量模型,两个霍尔元件与磁体构成对称互补结构,以差分方式输出信号电压。建立加速度与输出电压的线性关系,实现以非接触的方式测量加速度。模型的对称互补式设计,减小了非线性因素对测量的影响,改善了输出线性度。差分式电压输出,能够抑制共模干扰和零点漂移,并提高了信号幅度。对模型进行线性模拟实验,实验结果符合理论结论。数据分析显示,测量方法具有较高灵敏度和线性度。     

用霍尔传感器测量大电流

霍尔元件测量电流,是用霍尔元件检测通电导线周围的磁场来实现的。霍尔效应大电流计的特点是:结构简单、成本低廉、准确度高、测量时不需要断开回路。下面介绍几种用霍尔元件测量大电流的方法。     

轨道用霍尔传感器的应用

介绍了将霍尔传感器用做轨道接近开关的结构、磁路和电路设计方法.该传感器采用铁轨安装方式,用霍尔元件作为敏感元件,将霍尔元件固定于磁路中,通过检测元件输出信号变化,判断列车经过及车厢的位置.该传感器可用来检测由低速到高速运行的列车.     

新型非接触式电流传感器

1 原来状况 原来的非接触式电流传感器大致有3种结构模式,如图1所示.在图1中,例1所示为以霍尔元件作为磁场检测元件设置在铁芯的间隙内;例2所示为在铁芯的间隙内设置霍尔元件,而在铁芯上设置反馈线圈;例3所示为在铁芯的间隙内设置磁-光效应元件(应用法拉第效应的元件),用作磁场检测元件.     

电子罗盘

<正> 地球上每个地方的地磁场都有固定的方向和大小。线性霍尔元件可以检测地磁场的大小和方向。因此,线性霍尔元件可用来制作电子罗盘,也可根据实际需要制作指南针或指北针。 电路原理 本文介绍的电子罗盘电原理图如图1所示。所有放大指示电路由一块四运放LM324组成。霍尔元件H的电源由总电源经限流电阻R4、R5后提供。霍尔元件产生的霍尔电动势加在运算放大器IC1的同相和反相两个输入端上。IC1输出电平调整通过R1、R2和W分压方式实现。IC1的电压放大增益由R7决定。驱动放大级由LC2担任。R9、R10提供同相输入端电平。R11决定LC2的增益,输出信号既可由LED指示,又可由     

谈谈录像机中的霍尔集成电路

霍尔元件是利用霍尔效应制成的一种磁敏传感器件,而霍尔集成电路则是将霍尔元件、放大器、温度补偿电路和稳压电路利用集成电路工艺技术制造而成,它能感知一切与磁有关的物理量,并且输出相关的电信号。所以霍尔集成电路既是一种集成电路,也是一种灵敏度很高的磁敏传感器。一、霍尔效应霍尔效应原理如图1所示。将一块     

开关型CMOS霍尔传感器的设计

利用CMOS工艺制作的霍尔传感器一般失调电压较大。为了抑制霍尔传感器的失调电压,文中提出一种正交耦合旋转电流技术,利用开关改变失调电压的极性,经过采样相加抑制霍尔元件的失调电压,同时利用相关双采样技术降低电路失调电压。采用Cadence工具对电路进行仿真验证,3.3 V的供电电压下,平均失调电压为550 μV。结果表明,电路有效降低了霍尔传感器的失调电压。     

2阶Δ-∑励磁调节器ADS1208的应用

ADS1208是美国德州仪器(TI)公司生产的针对霍尔元件的2阶△-∑励磁调节器芯片。文中详细介绍了ADS1208的主要特点、工作原理,指出了使用 ADS1208实际设计电路时应注意的技术问题。     

Measuring system for development of stroke-sensing cylinder forautomatic excavator

In order to develop a stroke-sensing cylinder for automatic excavators equipped with Hall sensors of GaAs type, a measuring test facility is set up and used in investigating the design parameters. The measuring system itself is a kind of XZ table with two moving axes in X and Z directions, respectively, on which sensing parts, including Hall sensors, are installed. Furthermore, to attain a high precision of movement of the measuring system, a new sliding mode control is introduced, which diminishes chattering in the control loop by setting two dead zones along the switching line. The unknown parameters for sliding mode control are estimated by a signal compression method. The output signal from a Hall sensor was analyzed by using a measuring instrument. In particular, the detected signal according to the Hall sensor's movement on the piston rod, which has a magnetic scale, was investigated and the vertical distance between the Hall sensor and the piston rod, which gives direct effects on the detected signal, was obtained. Based on these results, the stroke-sensing cylinder was designed and fabricated     

A comment on "An extension and application of the Thompson-Lampard theorem"

This letter proves that the conductivity measuring technique presented by Rehman-Murti can be directly derived from the Van Der Pauw's method by a simple transformation of the current field. Hence, conclusions obtained for one method can be transposed to the other one. It is also proved that the Rehman-Murti structure can also be applied to Hall mobility measurements.     

An automatic smoothing algorithm for the calculation of impurity concentration from sheet resistivity and sheet hall coefficient data

A new processing algorithm is described for the conversion of incremental sheet resistance and sheet Hall coefficient data to impurity concentration, for the case of smooth unimodal carrier profiles. The method is based on two improvements to existing techniques. The first involves the application of an inverse error function complement transformation which attempts to linearize the experimental data. The second refinement, concerning the numerical differentiation of the data, includes the use of a cubic spline function and also a simple editing facility, so that the results obtained are not influenced by occasional poor data values. As an example of the power of these new techniques, results are given of an application to the sheet resistance data published by Plunkett et al.Full details of the extension of the algorithm to incorporate the use of sheet Hall data are described, and it is noted that the differentiation of the Hall and sheet resistance data are accomplished independently. Finally an application of the complete algorithm is described on new experimental sheet resistance and sheet Hall coefficient data.     

Carrier Transport Properties in the Doped Micro—crystalline Silicon Films

Doped micro-crystalline silicon films are deposited at temperatures as low as 400 ℃ by the catalytic chemical vapor deposition method using a silane and hydrogen gas mixture. Electrical properties such as the carrier concentration and the Hall mobility are investigated for various measuring temperatures. It is found that the grains of micro-crystalline silicon are preferentially oriented along the (220) direction , and that the Hall mobility is larger than 8 cm 2·V -1 ·s -1 , the carrier concentration is about 1×10 17 cm -1 ～1×10 19 cm -3 at room temperature.     

计算机辅助霍尔测量系统

霍尔测量是研究半导体材料性质的重要实验方法 ,文中设计、建立了一套计算机辅助测量系统 ,它能自动采集和处理数据。文中论述了该系统的组织构造、工作原理和软件实现。     

最大熵迁移率谱分析的发展与应用

最大熵迁移率谱分析方法是用于研究和获得材料电学参数一种测试手段。它克服了传统的固定磁场霍尔测量方法的缺点,可以获得更多更准确的电学信息。本文介绍了最大熵迁移率谱分析方法的基本原理和特点,论述了最大熵迁移率谱分析方法的发展与应用,最后展望了最大熵迁移率谱分析方法的应用前景。     

基于延迟捕获功能的血液切变率测量方法

对延迟捕获的基本原理进行了系统的分析,详细介绍了利用延迟捕获功能实现计时计数法测量转速的具体方法和实例.此方法已应用在粘度测试仪器中切变率指标的测量上,经实际使用表明具有软硬件结构简单、成本低、精度较高、运行可靠等优点,对于一些在嵌入式应用中需要测量转速指标时,可谓一种良好的方法.     

Increase of accuracy of definition of coordinates by multi-position passive complexes on a basis of difference-distance measuring method and the problem solution in redundancy conditions

It is proposed a method of definition of coordinates of radiation sources (RS) using difference-distance measuring method and the problem solution in condition of redundant information about target space location. It is considered mathematical tool for the problem solution in condition of redundancy, it is represented a validation of considered method of RS coordinates definition. It is carried out simulation of RS coordinates definition, and on a basis of statistic characteristics of simulation results it is shown increase of the accuracy of RS coordinates in case of application of given method in the system of passive radio location.     

动态定标原理及其应用

本文从测量技术中的通用定标原理出发，在传感器一定的线性传输特性范围内，提出了一种新的定标方案－动态定标方案，并以成份分析工作中对待测量所提出的计量控制值域为例，说明了这种定标方法在测量技术中的实现方法及其应用价值。     

200A峰值电流表的制作与应用

常用的交直流电流表只能测量直流电流和交流电流有效值。本文介绍了利用新型器件霍尔电流传感器制作的200A峰值电流表的工作原理、电性能和调试方法。按文中电路原理图制作的峰值电流表既可以单独测量使用，也可以作为测流组件安装在其他检测设备中配套使用。