A novel voltage output integrated circuit temperature sensor

The novel integrated circuit (IC) temperature sensor presented in this paper works similarly as a two terminal Zener, has breakdown voltage directly proportional to Kelvin temperature at 10 mV/℃, with typical error of less than ±1.0℃ over a temperature range from -50℃ to +125℃. In addition to all the features that conventional IC temperature sensors have, the new device also has very low static power dissipation ( 0.5 mW ) , low output impedance ( less than 1Ω), excellent stability, high reproducibility, and high precision. The sensor's circuit design and layout are discussed in detail. Applications of the sensor include almost any type of temperature sensing over the range of -50℃-+125℃. The low impedance and linear output of the device make interfacing the readout or control circuitry especially easy. Due to the excellent performance and low cost of this sensor, more applications of the sensor over wide temperature range are expected.

Design of Cold-Junction Compensation and Disconnection Detection Circuits of Various Thermocouples and Implementation of Multi-Channel Interfaces Using Them-A Secondary Publication

Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain.

Investigation of a Pressure Sensor with Temperature Compensation Using Two Concentric Wheatstone-Bridge Circuits

This study presents a silicon-based pressure sensor with temperature compensation. The eight piezoresistors were designed on the polycrystalline silicon membrane and constructed by two concentric Wheatstone-bridge circuits to perform two sets of sensors. The sensor in the central circuit measures the membrane deflection caused by the combined effects of pressure and temperature, while the outer one measures only the deflection caused by the working temperature. From this arrangement, it is reliable and accurate to measure the pressure by comparing the output signals from the two concentric Wheatstone-bridge circuits. The optimal positions of the eight piezoresistors were simulated by simulation software ANSYS. The investigated pressure sensor was fabricated by the micro electro-mechanical systems (MEMS) techniques. The measuring performance and an indication of the conventional single Wheatstone-bridge pressure sensor is easily affected under variation of different working temperature and causes a maximum absolute error up to 45.5%, while the double Wheatstone-bridge pressure sensor is able to compensate the error, and reduces it down to 1.13%. The results in this paper demonstrate an effective temperature compensation performance, and have a great performance and stability in the pressure measuring system as well.

基于磁性传感器的低失调温度补偿接口电路设计

面向磁性传感器在物联网(IoT)技术中的广泛应用,该文基于180 nm CMOS工艺设计了一种具有低失调电压,低温度漂移特性的霍尔传感器接口电路。针对霍尔传感器灵敏度的温度漂移特性,该文设计了一种感温电路并与查表法相结合,调节可编程增益放大器(PGA)的增益有效地降低了霍尔传感器的温度系数(TC)。在此基础上,通过在信号主通路中使用相关双采样(CDS)技术,极大程度上消除了霍尔传感器的失调电压。仿真结果表明,在–40°C~125°C温度范围内,霍尔传感器的TC从966.4 ppm/°C减小到了58.1 ppm/°C。信号主通路的流片结果表明,霍尔传感器的失调电压从25 mV左右减小到了4 mV左右,霍尔传感器的非线性误差为0.50%。芯片的总面积为0.69 mm^(2)。

一种基于锁相放大的谐振式密度传感器谐振频率测量系统设计

谐振式密度传感器测量密度的关键在于谐振频率的测量。现有的测频法、测周期法、FFT法等谐振频率测量方法因噪声、脉冲误差等因素限制了其精度。为了解决该问题,设计了一种以锁相放大器为核心的谐振频率测量系统,其检测电路将交流振动信号的测量转换为直流恒定电压的测量。利用实验中发现的谐振区域内该直流电压与激励频率呈近似线性关系,基于扫频思想提出并实现了一种谐振频率自动测量算法。在(20±0.05)℃环境下进行了密度标定实验,对密度传感器进行了温度补偿。实验结果表明,在密度为700 kg/m^(3)~1000 kg/m^(3)的测量范围内,测得谐振频率稳定性可达到0.002%,传感器的密度测量最大误差为0.48 kg/m^(3),最大综合测量误差为0.069%,验证了所提谐振频率测量方法的有效性、精确性。

基于Sm-PMN-PT和改进型DICH接口电路的压电取能功率提升方法

通过压电取能方式将电力设备表面的机械振动能转化为电能,是实现电力专用传感器无源化的有效途径之一。然而,传感器高集成度和小型化发展趋势对压电取能功率提出了更高要求。为此,提出一种基于钐掺杂铌镁酸铅-钛酸铅(Sm-doped Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3),Sm-PMN-PT)材料和改进型双中间电容回收(improved double intermediate capacitor harvesting,improved-DICH)接口电路的压电取能功率提升方法。首先,制备了不同Sm掺杂质量分数为x和PT质量分数为y的xSm-PMN-yPT压电双晶片,并对压电材料的性能参数进行了测试和对比;其次,在对比分析几种典型接口电路的基础上,设计了一种改进型DICH接口电路,并从理论上进行了取能功率的对比分析;然后,采用Multisim软件对不同接口电路的取能功率进行了仿真分析;最后,对Sm-PMN-PT压电双晶片和锆钛酸铅(Pb(Zr1–xTix)O3,PZT)压电陶瓷在不同接口电路下的取能功率和能量提取效率进行了对比测试。研究结果表明:基于2.5%Sm-PMN-32%PT材料和改进型DICH接口电路的压电取能装置具有516.3μW的高输出功率、61.1%的高能量提取效率和较强的负载适应性,在取能领域具有良好的工程应用前景。

一种基于MIPI D-PHY物理层的高速比较器

基于MIPI D-PHY物理层传输协议,文章设计一种高速低功耗的自偏置比较器电路,并对电路进行理论分析和仿真验证。该高速比较器总体结构由二级运放构成:共栅极和共源极以及工作在线性区的NMOS管组成第1级放大结构;电流源作负载的四管运放组成第2级放大结构。差分信号通过NMOS源极进行输入,提升信号的共模电压接收范围。电路结构中无额外电流源偏置,提高数据传输速率的同时减小了功耗。基于SMIC 0.18μm CMOS工艺设计,采用1.8 V电压供电,仿真结果表明:高速比较器能准确接收低共模电平的差分信号,直流增益为37.4 dB,传输速率达到2.5 Gb/s,功耗达到326μW/(Gb/s),可以接收到差分信号的共模电平范围为30~330 mV。

柔性超导电路制备工艺技术研究

超导转变边沿探测器是坎德拉单位量子化复现和单能X射线量子计量的核心器件。大规模超导转变边沿探测器阵列探头的信号读出需利用柔性超导电路将信号传输至探头侧面的超导量子干涉器件。柔性超导电路是将超导信号线制备在柔性聚酰亚胺衬底上以实现信号低热导率、无阻传输。以硅片作为临时支撑,电子束蒸发100 nm Cr膜作为剥离牺牲层。非光敏聚酰胺酸旋涂在Cr膜上固化后,通过紫外曝光、溅射薄膜沉积和剥离等工艺制备Nb/Al薄膜传输线结构,利用Cr膜高应力特性将聚酰亚胺薄膜从硅片上剥离,湿法腐蚀Cr膜完成柔性超导电路的制备。测试的40根Nb/Al传输线的超导转变温度T_(c)为8.91~9.02 K,剩余电阻比r_(RR)为5.83~6.96。温度为8 K时,38根传输线临界电流I_(c)超过1 mA;温度为4.2 K时,所有样品I_(c)均超过1 mA,其中有25根传输线I_(c)超过10 mA,满足超导转变边沿探测器阵列测试需求。

基于对称型双谐振电路的LTCC温湿传感器

为了实现高温、恶劣环境下温度和湿度复合参数测量,设计了一种基于对称型双谐振电路的双参数传感器。该传感器采用了一种独特的对称型双谐振电路,可解决多参数间物理性串扰的难题。首先通过高频结构模拟器(HFSS)对传感器电场进行仿真,采用低温共烧陶瓷(LTCC)技术对传感器进行制备,最后搭建温度和湿度平台测试并验证了传感器的可行性。测试结果表明,两个被测参数的谐振频率彼此完全独立、解耦,其中传感器的最高测试温度为500℃,随着温度的升高,温度灵敏度逐渐升高,在25~300℃、300~400℃和400~500℃范围内,温度灵敏度分别约为0.0116、0.0259和0.0493 MHz/℃,湿度灵敏度约为0.043 MHz/%RH,传感器对温度和湿度测量均表现出了良好的敏感特性。

超低温铂电阻传感器及其变换电路的线性参数研究

本文重点对超低温(-200℃以下)的传感器测量进行分析研究,针对低温条件测量的温敏特性和变换电路进行系统性研究,根据铂电阻在低温下的特性曲线,利用电路的反馈原理,修正铂电阻的线性参数,按照直线方程给出温度—电压关系时,该线性参数的修正可以有效提高传感器/变换器精度,保证传感器测量超低温环境时,不受铂电阻自身低温非线性带来的弊端,通过试验验证可以得出,传感器在-250~100℃全温区范围内精度可以达到0.95%,保证对低温环境的精确测量。

太空设备用单片集成电路筛选方案研究

随着太空研究进程不断加速,空天优势已经成为现代竞争中取胜的重要环节。如果偶然失效或者有质量隐患的元器件上装应用,会导致太空设备整机早期故障率大大增加。装备对太空设备用元器件的质量与可靠性提出了战略需求。文中基于太空设备的典型应用环境,在充分调研国内外元器件标准体系及质量控制模式的基础上,利用FMEA技术分析元器件的敏感因素。基于薄弱环节建立分级分类的筛选方案,支撑太空设备用元器件可靠性保证工作,避免早期失效或有质量隐患的元器件上装应用,满足太空设备对元器件质量、成本及研制周期的要求,助力空天装备快速、高质量和可持续发展。

某型润滑油温度传感器感温故障研究

针对某型润滑油温度传感器感温故障现象(信号输出异常),通过拆解排查和X射线方法,对润滑油温度传感器进行故障定位及故障模式分析,定位出故障点为感温组件,故障模式为开路。采用故障树法逐次分析可能导致感温组件开路故障的因素,得出以下结论:焊接过程中的高温沿内引线往薄膜元件传导,使元件加固树脂烧蚀或受热严重膨胀,导致加固树脂及引出线松动脱落,引出线与金属膜之间接触不良,最终造成感温组件经过高温或温度循环后开路。根据失效机理分析和试验,该型润滑油温度传感器感温组件开路问题分析定位准确,改进措施有效。

一种新型智能电容传感器设计

文章旨在改进传统电容式接近传感器抗干扰能力差,误触发频繁的问题。在充分调研国内外传感器的发展现状及应用市场基础上,新型智能电容传感器的硬件重新设计了振荡电路、单片机控制电路和IO-LINK驱动电路,软件使用了自适应的投票算法和自动示教功能。新型智能电容传感器在安装方式上支持三芯电缆的IO-LINK模式,可实现简单快速对传感器的过程数据进行扩展诊断,提升现阶段电容传感器的智能化水平,同时为同类新型产品的研发提供有效的解决方案。

Development of capacitive sensor signal conditioning system for angular displacement measurement using timer IC LM555 and UFDC

In this research paper,we have presented variable area type capacitive sensor signal conditioning system for angular displacement measurement and for this purpose we have used timer LM555 based astable multivibrator and universal frequency to digital converter (UFDC). Due to variation in angular displacement in the variable area type capacitor which is connected in the timer based astable circuit,capacitance changes which in turn changes the time period of the timer circuit output. The time period of the timer output waveform is linear with the capacitance and hence linear with angular displacement. The timer output is further processed with UFDC for the measurement. The experimental results show that the time period is linear with the angular displacement in the range of 0- 180° and the uncertainty we should associate it with this average time period value is the standard deviation of the mean,often called the standard error (SE),which is ± 0.023 μs. Because of the simplicity,this measurement system can be used in both electronic and industrial instrumentation.

Research on key techniques of expendable conductivity temperature depth measuring system

This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.

地层压力动态响应的精确测量

精确测量地层压力动态响应能够准确快速地获得地层压力参数,是油气田勘探开发的重要环节。介绍了地层测试器压力测量系统的基本组成,提出了一种地层压力动态响应的精确测量方案。该方案以Quartzdyne石英压力传感器为核心,基于混合厚膜集成电路的硬件采集电路和系统软件,通过IIC总线读取Quartzdyne石英压力传感器的压力计数值、温度计数值、温度标定系数和压力标定系数。再经过解算算法进行解算,从而计算出真实的压力值和温度值,得到地层压力动态响应的精确测量结果。归纳了地层压力动态测量中的4种常见问题:机械和电路系统异常、传感器本身异常、作业方案设计不合理和井壁不光滑。提出的地层压力动态响应精确测量方案已经过渤海油田上百口井数年的实际应用,能够满足175℃下地层压力测试的需求。

混动汽车电池管理系统温度采样电路设计研究

为了实现混动汽车电池智能化管理,选取电池组温度作为采样指标,利用NLV74HCT4851芯片搭建温度采样电路。该电路以温度传感器作为信号采集装置,通过对信号进行放大、调理处理,按照电压信号与温度信号之间的关系,转换信号以获取温度值。测试结果表明,该电路设计方案能够实现电池组的温度采集,时间周期控制良好,并且检测采样精度有所提升,可以作为电池智能化管理的辅助工具。

微波电路互联用金丝键合界面空间高低温特性演化研究

金丝材料应用于航天器小型化微波模块等产品的电路封装中,金丝键合界面受高低温环境影响易产生性能变化从而影响服役可靠性。本文对金丝界面高低温特性的演化规律进行了研究,包括空间温度环境模拟试验后的界面与成分迁移、界面层厚度变化、键合金丝拉伸剪切力与失效模式演变,得出不同温度条件处理后的金铝键合界面微观组织变化规律。结果表明高低温循环试验后金丝界面仍保持较高的结合强度,一定程度的金属间化合物生长提高了键合界面强度。高温贮存试验中,随着贮存时间的增加,金丝界面层IMC(Intermetallic Compound)厚度和金属间化合物不断增长,失效破坏位置越来越多地出现在键合界面处,铝金属化层附近的金含量因扩散而增高,金铝键合界面处IMC界面层厚度的增加降低了界面结合强度。

集成ASIC补偿电路的高温动态MEMS压力传感器

随着工业技术的进步,高温高动态压力传感器的应用需求显著增加。提出一种集成专用补偿电路的高动态硅压阻式微电子机械系统(Micro-Electro-Mechanical Systems,MEMS)压力传感器,进行压力敏感芯片的结构设计和加工工艺设计,并对压力传感器进行封装和温度补偿电路设计。多层绝缘体上硅(Silicon On Insulator,SOI)材料能够使传感器在高温环境下正常工作。无引线的封装方式可有效提升传感器的频响性能。传感器后端集成了桥阻式专用集成电路(Application Specific Integrated Circuits,ASIC),能够显著减小传感器的体积,同时提升传感器整体性能。该MEMS传感器通过自动压力测试系统进行性能试验,结果表明MEMS压力传感器经过补偿后能够实现较高的线性度、稳定的零点输出特性以及理想的动态输出特性。

一种可应用于无源RFID的新型CMOS温度传感器设计

针对无源RFID低功耗的应用需求,基于SMIC 0.18μm CMOS工艺设计了一种低功耗CMOS温度传感器。该传感器首先基于双晶体管电路将温度信号转换为与之成正比的电压信号,并进一步转换为电流信号,然后通过振荡器电路转换为频率信号,最终经计数器后转换为与温度对应的二进制数字信号输出。仿真结果表明,在-20~100℃范围内传感器具有良好的线性度和温度精度,且传感器总功耗仅为1.05μW,可满足无源RFID领域应用需求。