宽测量范围温度敏感IC

外接的一只双极型晶体管作为敏感元件的数字式“远端放置”温度传感器,是多年以来人们倚重的、用以检测高速、高性能芯片(如微处理器、图形处理器和FPGA等)温度的一种敏感器件。对于保证最佳性能和防止灾难性事故而言,精确的温度监控具有关键意义。温度监测装置协助系统对风扇进行控制并实现时钟减速(clockthrottling)功能,以便让高性能IC的工作温度保持在必要的范围之内。温度更高时,可以用它来关闭系统以防止出现故障。随着性能和功率水平的提高,远程温度监控功能变得越来越重要,其实现也越来越困难。几乎所有传统数字温度传感器IC的…     

红外热成像仪温度场测量的几何信息还原

针对温度场的热成像结果中缺少被测表面的几何位置信息并难以用直接的数学方法进行恢复的问题,提出用在被测表面设置红外可视校准网格的实验方法来建立物平面与像平面间的几何对应关系,并用一阶二维插值算法来还原热像结果的几何位置信息.通过对一个柱面射流冲击冷却温度场的测量验证了该方法的可行性.     

How Wind Affects Passive Microwave Measurements of Sea Surface Temperature

Uncertainty in the wind speed is a major source of error in passive microwave measurements from satellites of sea surface temperature (SST) because of the non-linear relationship between sea surface emissivity and wind speed. The accuracy of the SST measurement that can be achieved with only passive microwave measurements was assessed by computer modeling. Our investigation showed that the second-order terms must be included in the equation of radiative transfer in an analysis of the errors in the retrieved SST. In addition, we found that the effects of wind roughening and foam production should be treated separately. We have concluded that the accuracy of SST measurements would be improved by including data from an active remote-sensing instrument such as a scatterometer.     

Temperature stability of ultrahigh-speed GaAs JFET ICs

Ultrahigh-speed digital integrated circuits (ICs) implemented with GaAs/int JFETs are confirmed to be reliable in a wide variety of temperatures. Divide-by-256/258 dual-modulus prescaler ICs using source-coupled FET logic (SCFL) circuits that can operate up to 9 GHz have temperature coefficients of operating frequency stability and input power sensitivity of -17.2 MHz/degree and +0.12 dBm/degree between -20 and +100°C, respectively. Direct-coupled FET logic (DCFL) circuits were also confirmed to have very small temperature coefficients. The variations of the maximum operating frequency and the input power sensitivity of the DCFL divide-by-4 divider IC are -1.93 MHz/degree and +0.47 dBm/degree, respectively, between -60 and +100°C. The variation in the threshold voltage of the JFET is -0.88 mV/degree which is very small for the temperature stability of GaAs digital ICs     

矸石山温度场红外热像的空间信息挖掘

针对红外热像因其中缺乏与温度信息相对应的空间信息难以用于进一步分析的问题,提出通过布设覆盖矸石山表面满足一定条件的三角形控制网建立矸石山表面与热像的对应关系,通过插值提取红外热像的空间信息.设计实验验证了该方法的可行性并对误差进行了分析.     

集成电路低温特性的推断

随着极地及深空探测等领域的技术进步与发展,对IC的可工作温度范围提出了更高的要求,尤其是低温工作范围。换言之,军用级IC-55～125℃的温度范围已不能完全满足要求。通过3种航天器已经大量使用的通用集成电路温度特性的测试分析,以确定一种简单的、能够表征或推断IC低温工作特性的方法。     

Dynamic effects in the detection of bridging faults in CMOS ICs

Dynamic effects in the detection of bridging faults in CMOS circuits are taken into account showing that a test vector designed to detect a bridging may be invalidated because of the increased propagation delay of the faulty signal. To overcome this problem, it is shown that a sequence of two test vectors < T ₀, T ₁ >, in which the second can detect a bridging fault as a steady error, can detect the fault independently of additional propagation delays if T₀ initializes the faulty signal to a logic value different from the fault-free one produced by T ₁. This technique can be conveniently used both in test generation and fault simulation. In addition, it is shown how any fault simulator able to deal with FCMOS circuits can be modified to evaluate the impact of test invalidation on the fault coverage of bridging faults. For any test vector, this can be done by checking the state of the circuit produced by the previous test vector.     

Temperature Study of Sub-Micrometric ICs by Scanning Thermal Microscopy

Surface temperature measurements were performed with a scanning thermal microscope mounted with a thermoresistive wire probe of micrometric size. A CMOS device was designed with arrays of resistive lines 0.35 mum in width. The array periods are 0.8 mum and 10 mum to study the spatial resolution of the SThM. Integrated circuits (ICs) with passivation layers of micrometric and nanometric thicknesses were tested. To enhance signal-to-noise ratio, the resistive lines were heated with an ac current. The passivation layer of nanometric thickness allows us to distinguish the lines when the array period is 10 mum. The results raise the difficulties of the SThM measurement due to the design and the topography of ICs on one hand and the size of the thermal probe on the other hand.     

集成电路动态老化新技术的实施

在集成电路的可靠性评估试验中,动态老化项目是最重要的试验之一。文章提出了利用新技术对集成电路进行动态老化测试的全新方法,该新方法可以对老化线路板的关键电路信息和老化环境进行多路全面测试的监控,全面提高监控范围,及时发现老化过程中的工作异常,并减少人工,提高评估试验的可靠性,和其他方法相比有独特的优势。文中在技术上就集成电路具体实施动态老化试验过程中的技术细节和功能的实现进行探讨,分析和介绍老化技术中老化信号的生成和加载方法以及实时监控、数据采集方案。     

多显数字温度传感器的研制

为了提高温度测量的精确度,实现对温度的控制,采用美国DALLAS公司生产的一线式数字温度计芯片DS18B20并结合单片机技术可以达到所需目的,所形成的温度传感器结构简单、精度高、使用范围很大、使用灵活.     

联用动态EMMI与FIB的集成电路失效分析

EMMI被广泛应用于集成电路的失效分析和机理判定。针对端口I-V特性曲线的异常现象,采用静态电流的发光效应对漏电点进行光发射定位。静态电流法无法全面测试集成电路内部逻辑单元,需要使用动态信号驱动集成电路,使内部失效部位能够产生光发射。对样品在动态失效工作状态进行光发射捕捉,再结合良品对比、电路原理图和版图分析等辅助手段进行故障假设,以定位失效点,最后利用FIB系统对电路进行剖面切割制样,找出物理损伤点。对砷化镓数字集成电路的不稳定软失效案例进行分析,动态EMMI法与FIB系统联用可成功应用于芯片内部金属化互连异常的失效分析,解决传统静态光发射法无法定位的技术难题。     

T/R组件功放芯片瞬态温度响应研究

T/R组件的热设计是有源相控阵雷达的核心技术之一。在脉冲周期状态下,T/R组件中的功放芯片在很短的时间内,芯片沟道温度会产生快速的变化。针对芯片在脉冲周期中的瞬态温度响应问题,对芯片沟道温度的瞬态变化进行仿真研究,并利用红外热分析仪进行测试验证。将仿真结果与实验结果进行对比,两者结果吻合较好,满足T/R组件的使用要求。     

Thin-Film Temperature Sensors for Biological Measurements

Dynamic as well as static temperature measurements are now possible in biological tissue using thin-film Cu-Ni microthermocouples. These probes which use a quartz substrate exhibit response times of less than a millisecond with thermal properties similar to tissue. Their thermoelectric EMF of 21 , ?m V/°C is linearly dependent on temperature over the range normally encountered in biological measurements. Probe-tip diameters as small as 10 ?m are being fabricated.     

空间交叉CARS测量NO气体的温度

测量了不同温度下NO气体的空间交叉相位匹配CARS光谱,并将其与理论计算谱进行拟合,从而实现了用CARS方法测量系统中点的温度。     

卫星地球站系统噪声温度的测量

卫星地球站的品质因数G／TSYS是一个十分重要的指标。而限于客观条件，G／TSYS中的关键参数——系统噪声温度TSYS的测定往往难以实施。笔利用单位现有的仪器设备，实现了业余条件下对TSYS的测定，为地球站的设计和建设提供了参考数据。     

射频集成电路发展趋势

据市场调研咨询公司In-Stat/MDR的研究者称,到2005年全球所有家庭和办公室的无线以太网(Wi-Fi)接入点将达4400百万个。.现有频带中消费电子设备信号的干扰日益增加。与日俱增的通信需求已给通信业提出了挑战。骨干网络的传输速度业已提升到万亿位每秒,光纤也正进入局域网和广域网。此外,第三代系统(3G)不久将取代两代半系统(2.5G),包括通用便携无线服务(GPRS)、乃至改进数据速率GSM服务(EDGE)。为进一步改善移动通话质量并能提供可视服务,选择适当的工艺技术将不像以往那样简单,设计者将要面对诸多的抉择。工艺技术以往,用于移动电…     

Fault-Tolerant ICs: The Reliability of TMR Yield-Enhanced ICs

The use of triple modular redundancy (TMR) for reliability enhancement is well known. This paper presents a simple method' for predicting the reliability of integrated circuits (ICs) which use TMR for yield enhancement. A simple yield-model is included as it is necessary to factor in the effect of consumption of redundancy paths due to wafer fabrication defects. TMR implementation is briefly discussed as well.     

Dynamic life-estimation of CMOS ICs in real operating environment:precise electrical method and MLE

The functionality of an IC in field use can be maintained by replacing an IC shortly before its anticipated failure. An accurate estimation of circuit lifetime is important in selecting a replacement time to: (1) avoid unanticipated circuit failure by replacing them as early as possible; and (2) use the IC fully by replacing them as late as possible. Since the problem is different from lifetime estimation with accelerated test results, this approach continually measures circuit performance and then analyzes the measurements statistically. The whole estimation process is covered from selection of circuit parameters for performance measurement to development of an aging model for the statistical analysis. The circuit-delay change due to hot-carrier effects is selected to quantify the performance degradation; an aging model, founded on the hot-carrier induced failure mechanism, is developed. Maximum likelihood estimation (MLE) is used for the statistical characteristics of future aging, where the severity of the operating environment is assumed to be a stationary random process. The MLE are used to choose an efficient time for IC replacement. The practical use of the suggested method in IC maintenance is demonstrated with statistically simulated data     

Surface Current Measurements with an Electric Probe

The use of an electric probe for measurement of induced surface currents on obstacles in a parallel plate region is described. An analysis of the sources of error, and in particular the interaction of the probe with the obstacle, is examined theoretically and experimentally. It is concluded that the technique is capable of yielding measurements of good accuracy.     

Ovulation Detection by Internal Cranial Temperature Measurements

A simple method for recording a patient's internal cranial temperature is described. Using these measurements it is shown that the drop and rapid rise in basal temperature indicative of ovulation can be easily detected and recorded. The superiority of cranial temperature over oral temperature is demonstrated by indicating the occurrence of ovulation one full day before a like indication in oral temperature. Evidence is also given for choosing cranial over rectal temperature for use in detecting ovulation.