隔离型DC/DC在高压电压电流源设计中的应用

由于隔离型DC/DC的安全性、隔离性等特征,该类器件广泛应用于多个电子、工业领域,本文主要介绍了隔离型DC/DC在高压电压电流源中的应用。本文将隔离型双输出DC/DC引入设计,利用DC/DC的隔离特性,将电压电流源的次级输出作为DC/DC器件参考地,将DC/DC器件的两路输出电压作为相关运算放大器的电源电压。常规高压电压电流源设计中需要大量采用高压运算放大器,采用此方案可使用较少的高压运算放大器及更低的成本实现相同功能,同时降低高压电源对PCB电路板上信号的影响。通过实际测量,文中方案输出稳定、精度高,满足设计与使用要求。文中用功能图纸对此类应用进行了详细说明。     

Voltage-to-frequency converter with high sensitivity using all-MOS voltage window comparator

A high-sensitivity voltage-to-frequency converter (VFC) using an all-MOS voltage window comparator is presented in this work. The circuit is composed of one voltage-to-current converter, one charge and discharge circuit, and one all-MOS voltage window comparator. The input voltage is converted into a current which in turn triggers the charge and discharge circuit, where a built-in capacitor is driven. The voltage window comparator monitors the variated voltage on the capacitor and generate an oscillated output of which the vibration frequency is linearly dependent to the input voltage. In this way, the worst-case linear range of the output frequency of the proposed VFC is 0-55.40 MHz verified by simulations given a 0-0.9 V input range. The physical measurement of the proposed VFC shows a 0-52.95 MHz output frequency given a 0-0.9 V input range. The error in linearity is better than 8.5% while the power dissipation is merely 0.218 mW.     

基于MEMS静电微镜驱动器的光纤相位调制器

设计并制作出了一种基于MEMS静电微镜驱动器的光纤相位调制器。MEMS静电驱动器采用垂直梳齿驱动技术,驱动硅微反射镜沿其法线方向的垂直平移运动以实现入射光波的光相位调制。MEMS静电微镜驱动器与光纤准直器耦合构成MEMS光纤相位调制器,避免了拉伸光纤或改变折射率的困难,具有MEMS技术批量制造、低成本等优势。采用MEMS工艺成功制作出MEMS光纤相位调制器,并实现Michelson光纤干涉仪。利用ASE宽带光源对光纤相位调制器的静态调制特性进行测试,采用Michelson光纤干涉仪对光纤相位调制器的动态调制特性进行测试,结果表明,MEMS光纤相位调制器50V偏压实现了1 550nm光波的2π相位调制,当器件谐振频率为7.15kHz以及交、直流电压幅值分别为12.5V时,响应幅值可达6.8μm,可以实现多个2π的相位的正弦调制。     

汇川技术HD92高压变频器在高炉鼓风机上的应用

本文介绍了汇川技术HD92系列大功率高性能高压变频器在钢铁行业高炉鼓风机上的成功应用,系统采用了双机并联方案,并且具备工变频的无扰切换功能,能够实现单台故障时,另一台不停机且能够无扰切换至工频运行。     

悬浮型高压窄脉冲放大器的研究

悬浮型高压窄脉冲放大器输出的是脉宽100ns、上升/下降沿10ns的高压脉冲,运用其中的DC/DC变换器处于动态悬浮隔离供电状态.为使DC/DC变换器适用于高压瞬态跃变状态,首先要求DC/DC变换器的输入/输出耦合电容的存在不影响高压窄脉冲的质量,其次是输出高压窄脉冲时的高速瞬态跃变不会影响DC/DC变换器的供电稳定性.因此,研究悬浮型高压窄脉冲放大器的驱动方式,就是要着重分析动态运用中的DC/DC变换器的工作状态.     

小型化直流电源发展动态

随着电子整机向小型化、轻量化方向的发展，对整机所用的直流稳压电源也提出了小型化的要求。本文叙述了国外ＤＣ／ＤＣ变换器的研究与开发情况，介绍了国内发展集成化直流稳压电源的现状，分析了国内市场对ＤＣ／ＤＣ变换器的需求。对国内外在该领域的技术水平进行了比较，提出了发展我国小型化直流电源的对策。     

小体积高压电源的固体封装技术

本文介绍了一种小体积高压电源固体封装技术要点.给出了有关试验数据,指出小体积高压电源的封装技术是工艺、结构、电路三方密切配合的结果.采用这项新技术,可以有效地缩小电源体积,避免高压电源(组件)在湿热环境或低气压下产生电晕、飞弧;或者因电晕产生过载致使某些元件损坏,从而提高部件的可靠性.     

一种基于硅基MEMS三维异构集成技术的T/R组件

基于硅基微电子机械系统(MEMS)三维异构集成工艺,设计并制作了用于相控阵天线系统的三维堆叠式Ku波段双通道T/R组件。该组件由两层硅基结构通过球栅阵列(BGA)植球堆叠而成,上下两层硅基封装均采用5层硅片通过硅通孔(TSV)、晶圆级键合工艺实现。组件集成了六位数控移相、六位数控衰减、串转并、电源调制、逻辑控制等功能,最终组件尺寸仅为15 mm×8 mm×3.8 mm。测试结果表明,在Ku波段内,该组件发射通道饱和输出功率大于24 dBm,单通道发射增益大于20 dB,接收通道增益大于20 dB,噪声系数小于3.0 dB。该组件性能好,质量轻,体积小,加工精确度高,组装效率高。     

Fabrication of 3D MEMS toroidal microinductor for high temperature application

Based on Microelectromechanical systems (MEMS) technique and thick photoresist lithography technology, a new toroidal-type inductor for high temperature application has been successfully developed. In the fabrication process, heat-resistant materials are used, alumina as insulator and supporting materials instead of polyimide, heat resistant glass for underlay instead of normal glass, and copper for coil. The maximum inductance is 87 nH at 0.826 GHz and maximum of quality factor (Q-factor) is 4.63 at 0.786 GHz, at room temperature. With simulation of thermal deformation, it shows that the developed toroidal inductor can be suitable for high temperature application, from 300 to 700 °C.     

某高压电连接器的失效分析

针对某型号高压电连接器在电压冲击试验中的失效现象,进行失效分析.分析手段包括X 射线检查、内部检查和金相分析等.检测发现该元件存在多芯导线压接损伤、剥线损伤等缺陷.根据该高压电连接器的失效模式和各项检测结果,分析得出了其失效机理.最后,在元件设计、工艺控制、质量监控方面提出了改进建议.建议实施后该元件通过了各项检测,质量可靠性得到了提升.     

Electrically Enhanced Readout System for a High‐Frequency CMOS‐MEMS Resonator

The design of a CMOS clamped‐clamped beam resonator along with a full custom integrated differential amplifier, monolithically fabricated with a commercial 0.35 μm CMOS technology, is presented. The implemented amplifier, which minimizes the negative effect of the parasitic capacitance, enhances the electrical MEMS characterization, obtaining a 48 × 10⁸ resonant frequency‐quality factor product (Q×f_res) in air conditions, which is quite competitive in comparison with existing CMOS‐MEMS resonators.     

CMOS MEMS技术的现状及展望

简要介绍了MEMS的发展状况及CMOS工艺在MEMS中的地位。主要介绍了pre-CMOS，intermediate-CMOS和post-CMOS三种不同的CMOS MEMS工艺。详细讨论了CMOS MEMS今后将面临的挑战及其未来应用领域，最后，根据国内情况对我国CMOS MEMS的发展提出了建议。     

交直流隔离的分布式MEMS移相器设计

设计了一种五位分布式微电子机械系统（MEMS）移相器,通过分析对比传统分布式MEMS移相器加载直流偏置的两种方式,提出了一种新的直流偏置的加载方式,能解决传统方式带来的交直流干扰和引线繁杂问题,同时工艺容易实现。采用ADS软件对移相器进行级联仿真,优化了微波性能参数,仿真得出移相器在35 GHz时移相精确度小于3°,移相器的插入损耗小于0.5 dB,回波损耗大于23 dB。给出了五位分布式MEMS移相器的工艺流程,同时验证了所设计加载直流偏置方式工艺简单的优势。     

一种用于升压型DC/DC变换器的低压带隙基准源

设计了一种应用于升压型DC/DC转换器芯片的高精度、低电压、低功耗带隙基准电压源,包含恒定电流的偏置电路、低压低功耗的运算放大器、三极管级联的带隙基准核心电路和低压启动电路四个部分。经过理论分析和仿真模拟,采用华虹NEC的5 V 0.35μm 1P4M工艺流片成功。电路实测结果为:输出电压Vout=1.2 V,温度系数12.5 ppm/℃,工作电压1.3~5 V,随电源电压的变化率为0.78 mV/V,3 V供电下功耗9μA。该带隙基准源可用于实际产品的批量生产。     

高稳定性Buck型DC/DC变换器设计

提出了一种基于模拟反馈的高稳定性Buck型DC/DC变换器的结构,使得电路在输入电压和负载变化时,具有输出电压稳定,波动范围和纹波小的特点.根据基于UMC 0.18μm工艺下的模型参数,使用Hspice对整个变换器进行仿真,给出了仿真结果表明电路设计的正确性.     

一种55 V输出小功率DC/DC变换器的设计

介绍了一种小功率混合集成DC/DC变换器的设计思想、实现方法及测试结果。设计的电路采用光隔离单端反激式拓朴结构和混合集成工艺技术制作,输出电压为55 V,输出功率小于2W,工作温度为-55~105℃,体积为27 mm×27 mm×6.5 mm。该电路具有电压稳定、精度高、纹波小、调整率优良和可靠性高等特点,可应用于各类精密电子设备中。     

RF MEMS技术

通信收发机、天线等无线设备的发展趋势是高性能、小体积、低成本。微电子机械系统技术在这一趋势中显现了技术潜力。本文阐述了RFMEMS技术的现状。     

一种Ka频段高密度高集成瓦式T组件的设计

介绍了一种Ka频段瓦式T组件的设计方法和关键技术.采用多层印制电路板(Printed Cir-cuit Board,PCB)技术,实现了无源网络和馈电网络集成在同一块多层电路板上,滤波功能层和天线一体化集成,利用毛纽扣实现了组件的三维垂直互联.采用互补金属氧化物半导体(Complementary Metal Oxide...     

Evolution of a CMOS Based Lateral High Voltage Technology Concept

This work describes the evolution of a CMOS based lateral high voltage (HV) technology concept, where the HV part is integrated in a low voltage (LV) CMOS technology. The starting point is an existing substrate related state of the art 0.35 μm LV CMOS technology (C35) which is optimized for digital and analog applications. The technology covers two different gate oxide thicknesses which allow to control two LV logic levels with different gate voltages and drain voltages (max.V_GS=max.V_DS=3.3V, max.V_GS=max.V_DS=5.5 V). The key requirement for the HV integration is to preserve the LV design rules (DR) and the LV transistor parameters. Only in this case it is possible to reuse the digital and analog intellectual property (IP) blocks. The major challenge of this integration is to overcome the relatively high surface concentration of the 0.35 μm CMOS process which defines the threshold voltages and the short channel effects. Because the HV devices use the same channel formation like the LV devices, a process concept for the drift region connection to the channel is the key point in this integration approach. A benchmark for the process complexity is given by the mask count (low volume production) and the number of alignments (high volume production). Starting from a very simple approach n-channel HV transistors are described which can be integrated in the substrate related LV CMOS concept without adding additional masks. During the next steps the LV CMOS process is modified continuously using additional masks and alignment steps. From each step to step the new HV properties are explained and the trade-off between process complexity and device performance is discussed.     

A new MEMS based variable capacitor with wide tunability,high linearity and low actuation voltage

We have proposed a new RF MEMS variable capacitor to achieve high linearity, wide tunability and low actuation voltage. The idea is based on increasing the linear region in the gap between the plates of the capacitor. It is done by adding a fixed-fixed beam below the fixed-free beam. The fixed-free beam is one plate of the capacitor. The voltage is applied to the fixed-free beam. In the vicinity of the pull-in voltage, the fixed-free beam losses its equivalent stiffness. The fixed-fixed beam is located in the vicinity of pull in situation of the fixed-free beam. This condition increases the equivalent stiffness of the fixed-free beam and allows the beam to continue moving down linearly and consequently increases the maximum capacitance of the structure. Geometrical and material property effects of the second beam on the linearity, tunability and voltage are investigated. The governing nonlinear equation for static deflection of the beam based on the Euler–Bernoulli beam theory has been presented.