光学双稳态在光纤传感器的应用

光强调制型光纤传感器，已得到了广泛的应用，它的测量灵敏度，精度和稳定性，主要取决于光源输出功率的稳定性，传统的办法是采用引入参考光路，利用光电补偿方法，来减小光源波动造成的影响，我们提出采用光学双稳装置来稳定光源输出功率，并将它用於折射率调制型光纤传感器测量液体浓度的实验中，本文详细报导了该装置的原理，内容和测量结果，并指出进一步研究方向。     

A new NMOS temperature-stable voltage reference

An NMOS voltage reference has been developed that exhibits extremely low drift with temperature. The reference is based on the difference between the gate/source voltages of enhancement and depletion-mode NMOS transistors. The theoretical dependence of the reference voltage on both device and circuit parameters is analyzed and conditions for optimal performance are derived. The reference NMOS transistors are biased to the optimizing current levels by a unique feedback circuit. The measured output voltage drift in the integrated realization agrees well with theory and is less than 5 parts per million per degree Celsius over the temperature range -55/spl deg/ to +125/spl deg/C.     

微弯型光纤传感器光源光强的新的稳定方法

本文详细报导了该装置的原理，内容和测量结果，并指出进一步研究方向。     

The mechanical stress resistance capability of stress buffer structures in analog devices

In this research, we showed that the different stress buffer configurations in the analog device will change the magnitude of the mechanical stress effect on the device surface, which will cause the variation in the output voltage characteristic of the device as well. And, the experimental results reveal that the different stress buffer configurations provide the difference of the mechanical stress resistance capability on the LDO (Low Drop Out) analog device. The stress buffer structure can reduce the stress effect to the LDO analog device effectively, i.e., the variation of the output voltage character of the LDO analog device will be larger if there is no stress buffer structure on the LDO analog device. Our results could be a reference for the design of an analog device and its packaging to improve the performance of the analog device.     

一种阵列式版图布局的低温度系数CMOS带隙基准电压源

设计了一款低温度系数的自偏置CMOS带隙基准电压源电路,分析了输出基准电压与关键器件的温度依存关系,实现了低温度系数的电压输出。后端物理设计采用多指栅晶体管阵列结构进行对称式版图布局,以压缩版图面积。基于65 nm/3.3 V CMOS RF器件模型,在Cadence IC设计平台进行原理图和电路版图设计,并对输出参考电压的精度、温度系数、电源抑制比(PSRR)和功耗特性进行了仿真分析和对比。结果表明,在3.3 V电源和27℃室温条件下,输出基准电压的平均值为765.7 mV,功耗为0.75μW;在温度为-55~125℃时,温度系数为6.85×10~(-6)/℃。此外,输出基准电压受电源纹波的影响较小,1 kHz时的PSRR为-65.3 dB。     

Correlation-based fiber sensor using a holographic matched filter

The principle of a fiber sensor based on an optical correlation technique is described and assessed for its feasibility. The device measures the correlation between the far-field radiation pattern of a multimode sensing fiber and a reference pattern stored in a holographic matched filter. The output is a monotonically decreasing function of the changes in the patterns caused by the perturbance applied to the fiber. The results of some preliminary experiments are discussed and some drawbacks of the technique are pointed out     

Experimental validation of PTAT for in situ temperature sensor and voltage reference

Based on the CMOS proportional to absolute temperature principle, a combined device for voltage reference and temperature sensors is successfully implemented using a fully digital process. For a temperature range from 20 to 1208C, the experimental results show that the voltage reference has a temperature stable output of 717 mV and the associated temperature sensor has the sensitivity of 2.3 mV/8C with linearity up to 95%. They are independent of the variation of supply voltage.     

基于热释电型红外气体探测器的原始信号探究

作为采用非色散分光红外吸收光谱(Non-dispersed Infrared, NDIR)原理的红外光谱气体分析仪的一个核心器件,热释电型红外气体探测器输出信号的特征与后级信号处理息息相关。基于PYS3228TC_G1G20热释电红外气体探测器在不同调制频率下对激励源和输出的原始信号的同步跟踪,深入分析了激励源与探测器输出信号之间的关系。通过这些实验,总结并得出了热释电型红外探测器的初始信号特征,为热释电型红外气体分析仪的信号处理提供了重要的理论参考。     

一种可与微机兼容的12位D／A转换器

本文介绍并分析了一种可与微机兼容的１２位Ｄ／Ａ转换器的工作原理及其应用。该Ｄ／Ａ电路内有高稳定的齐纳隐埋基准，数字输入采用了两级缓冲锁存结构，片内含速输出放大器。本文给出了其主要性能指标性能指标及典型应用连接图。     

一种新型的混合型双频高功率微波器件

为提高高功率微波(HPM)器件的输出功率和转换效率,通过对磁绝缘线振荡器(MILO)和分离腔振荡器(SCO)的特性分析,提出利用MILO磁绝缘电流驱动的SCO替代收集极,构成一个具有更高输出性能的双频混合型HPM器件。通过全电磁粒子模拟软件的模拟,结果表明：L波段MILO-SCO混合型HPM器件可在1.54 GHz和0.74 GHz双频下工作,转换效率超过20%,对探索提高HPM器件工作性能提供了参考。     

DSPC6000环境下视频输入输出驱动程序开发

文中利用TI公司提出的类/微驱动模型的驱动程序结构,以基于TI公司TMSDM6437 DSP的视频处理系统平台,在DSP/BIOS的基础上设计了视频输入输出设备底层驱动程序（给出了主要的程序）,为高层程序开发人员提供方便的API接口函数来操作底层视频设备,提高了视频处理系统的开发效率。所阐述的视频设备驱动程序开发方法,对同类视频处理平台具有较好的借鉴性。     

自适应双参考磁场梯度探测原理

本文使用4个单分量磁探头构成双参考磁场梯度探测装置.4个探头组成3个磁场梯度传感器,其中一个为信号传感器,另两个为噪声传感器.以信号传感器输出作为原始输入,噪声传感器输出作为参考输入,采用自适应噪声抵消技术,能有效消除因载体运动产生的涡流磁场及因磁探头方向相对地磁方向改变而引起的噪声输出.本文提出的双参考磁场梯度探测装置具有工艺性好,灵敏度高,虚警概率低的优点,可在实际磁探系统中使用.     

Very-low-drop voltage regulator with a fully complementary power process

A very-low-drop voltage regulator is presented that uses an isolated-collector power p-n-p transistor structure to achieve an input-output voltage drop of 0.4 V at 1 A. The device includes a circuit which prevents quiescent current peaks when the p-n-p is in saturation and a Zener-zap trimmed reference makes possible /spl plusmn/1% output voltage tolerance.     

Status of the Microwave Power Transmission Components for the Solar Power Satellite

During the 1970-1980 time period a substantial advance has heen made in developing all portions of a microwave power transmission system for the solar power satellite (SPS). The most recent advances pertain to the transmitting portion of the system in the satellite and are based upon experimental observations of the use of the magnetron combined with a passive directional device to convert it into a highly efficient directional amplifier with excellent low-noise properties and potentially very long life. The ability of its microwave output to track a phase reference makes it possible to combine it with many other radiating units to provide a highfy coherent microwave beam. The ability of its output to track an amplitude reference while operating from a dc power source with varying voltage makes it possible to eliminate most of the power conditioning equipment that would otherwise be necessary.     

A sensitivity analysis of millimeter wave characteristics of SiC IMPATT diodes

Ionization rate coefficients and saturation drift velocities for electrons and holes are the vital material parameters in determining the performance of an IMPATT diode. We have performed a sensitivity analysis of the millimeter wave characteristics of 4H-SiC and 6H-SiC IMPATT diodes with reference to the above mentioned material data and an operating frequency of 220 GHz. The effect of a small variation in the ionization rate and drift velocity on the device characteristics like break down voltage, efficiency, noise measure and power output has been presented here.     

射频板条CO2激光器整形光路自适应调节研究

为了解决射频板条CO2激光器因安装或腔镜热畸变造成的光路偏移问题,采用外光路偏移补偿的方法对其进行校正。研究了基于压电陶瓷的偏移补偿装置,设计了压电陶瓷驱动电路,并分析了控制精度和自适应控制方法。结果表明,通过偏移补偿装置,激光输出功率在任何占空比下均可达到或超过标准参考功率值,并通过对比有无自适应调节,激光输出功率最大相差100W,且可保持激光输出功率在2h运行中波动小于2%。此项研究可保证激光器高效运行,提高激光器的输出功率和模式的稳定性,具有较大的实用价值。     

高压、高效率白光LED驱动电路的研究与设计

设计了一种高效率的高输入电压,恒定电流输出的白光LED驱动芯片.采用高压工艺,以脉宽调制(PWM)峰值电流的控制方式,实现了宽范围电压输入、恒定电流输出的LED驱动芯片的设计.内部集成了带隙电压基准源,产生0.25V的参考电压.芯片设计采用了高压横向扩散金属氧化物半导体场效应管(LDDMOS),设计了电压预调整电路,实现了输入电压范围在85V-400V间变化,输出电流在1毫安到1安培间设定.芯片仿真结果显示电能转换效率最高可达90%以上.     

单片式3.6μs pn结二极管存储相关器/卷积器

本文报道一种单片式金属氧化锌、二氧化硅(MZOS)结构存储相关器。在我国首次实现将参考信号“写入”(存储)二极管阵列中,然后用读信号将其“读出”,该器件也可用作卷积器。本文简叙了器件设计、结构、制作方法、工作模式和性能参数。     

Liquid-Core Directional Couplers Integrated With Silica Waveguides

Liquid-core directional couplers are fabricated in silica-on-silicon, monolithically integrated with silica waveguides at the input and output ports. The device output as a function of device length is shown experimentally using a series of devices of different lengths with toluene as the core medium. The experimental results agree with simulations, and the device is shown to be polarization insensitive. Applications in sensing, filtering and optical processing are discussed     

Frequency-adjustable clock oscillator based on frequency-to-voltage converter

A frequency-adjustable clock oscillator based on a frequency-to-voltage converter is presented. A new architecture is employed without reference frequency input. The system model shows the conditions of system stability. A compensation circuit was used to cancel the variations of frequency over process and temperature. The range of output frequency is from 22.5-360 MHz, which is within +4.5% variation in worst cases. The circuit was designed in a 0.13 μm CMOS 3.3 V device process, occupying a chip area of about 0.05 mm². The clock oscillator can achieve 25 ps peak-to-peak jitter, 2 μs locked time and consume 5 m W at a 3.3 V supply voltage and 200 MHz output clock.