新型高性能的高频信号发生器

介绍一种性能优良的高频信号发生器,对其产生信号的频率、占空比等技术指标进行了分析讨论,给出了它在电子技术中相应的典型应用实例,它产生的信号波形清晰、频率、相位和幅度稳定,失真度低,性价比高,具有较高的实用价值。     

一种高效的大功率宽带整流电路

提出了一种由π型匹配枝节、整流二极管、直通滤波器组成的高效大功率宽带整流电路。采用2只HSMS-282P肖特基二极管桥设计单级倍压整流电路,使电路在整流效率不下降的情况下提升输入的功率容量;采用π型匹配枝节实现阻抗匹配,使电路具有宽频特性,同时其并联短路枝节可以作为输入滤波器,实现小型化和整流效率的提高。直通滤波器用于抑制基频和二极管非线性产生的高次谐波,以提高整流效率。实测结果表示：在2.05~2.6 GHz带宽内整流效率大于60%;在2.45 GHz工作频率和35 dBm输入功率下,整流电路在330 Ω负载上获得70%的整流效率。该整流电路具有整流效率高、功率容量大、频带宽的特性,可为工程人员设计大功率微波整流电路提供设计指导。     

高度集成、功能丰富的32位MCU满足了消费电子和网络安全应用的需求

最近面市的32位MCU具有包括闪存、ADC和其他功能在内的一整套集成外设,而且处理能力也得到了增强.这些新型的MCU为家电应用、消费电子产品和网络安全应用提供了高性能、低成本的解决方案.     

一种高集成高空间分辨率220 GHz检波器

本文设计了一种高集成检波器,其包含贴片天线、匹配电路、肖特基二极管和透镜。在中芯国际130nm工艺下将天线、匹配电路、肖特基二极管集成到一个芯片上,检波器的集成度相比于分离式有了明显的提高。为增强片上天线的方向性,进行了带有空气腔的尼龙透镜的设计和优化。透镜上的空气腔不但提供了组装空间而且减小了透镜体积。通过测试,天线在220 GHz辐射增益为22 dB,其中透镜贡献约为20dB。检波器测试得到的响应率可达到130-150V/W,对应的等效噪声功率（NEP）估算为400-460 。     

Pseudospark switches for high repetition rates and high currentapplications

The state-of-the-art of pseudospark switch (PSS) development is reported. In addition to the replacement of thyratrons for high power applications in TE-gas-discharge lasers, PSSs have been tested at high repetition rates up to 2 kHz. In order to minimize the erosion rate and to reduce total switch inductance, multichannel PSSs with various geometrical configurations have been investigated: linear, coaxial, and radial arrangements of the parallel discharge channels. All three configurations possess distinct advantages in pulsed power technology, i.e. linear systems fit well into striplines. Beyond this, PSSs gain increasing importance in high current devices like fast pinches, plasma foci, or powerful modulators, i.e. for magnetoforming. A single-channel switch for hold-off voltages up to 30 kV at peak currents of ≈100 kA has been tested for a damped sinusoidal pulse of a 5 μs duration at a repetition rate of up to 0.2 Hz, with and without electrode cooling     

A high performances CMOS CCII and high frequency applications

In this paper, we propose an improved translinear based CCII configuration. Heuristic algorithm is used for optimal sizing regarding static and dynamic performances. PSPICE simulations for AMS 0.35 μm CMOS technology show that the current and voltage bandwidths are respectively 2.6 GHz and 3.9 GHz, and the parasitic resistance at port X (R _X ) has a value of 18 Ω for a control current of 100 μA. The improved configuration is used as a building block into high frequency design applications: a current controlled oscillator and a tunable fully integrable band pass filter. The oscillator frequency can be tuned in the range of [290–475 MHz] by a simple variation of a DC current. The central frequency of the band pass filter can be varied in the range of [1.22–1.56 GHz] and the quality factor vary in the range [8–306] with a simple variation of a DC current.     

New high power, high performance power converter systems

A new, high performance, low cost power converter system architecture is proposed. The system consists of a main converter and a multifunctional load conditioner. The main converter deals with most of the power flow running at a low switching frequency. The load conditioner is designed at a much lower power level running at a high-switching frequency. The load conditioner can (1) act like a current source and inject harmonic currents required by the load; (2) act like an active resistor to provide damping to the main converter; and (3) for three-phase inverters, decouple the coupling sources in the main inverter model in the rotating coordinates to make the control loop design for the main inverter much easier. The concept has been proved by simulation and experimental results on a 150 kW high performance three-phase utility power supply prototype. The proposed system configuration can be used in high power DC-DC converters, inverters, PFC and UPS applications     

一种用于大功率音频功放的高稳定性LDO

设计了一种用于大功率音频功放的高稳定性低压差线性稳压器(LDO),对其电路结构和工作原理进行了分析,重点讨论了上电预充模块、环路稳定性及电源抑制能力。采用0.18μm 1P4M BCDMOS工艺,不同工艺角下,Cadence Spectre仿真表明,LDO的温度系数小于47.45 ppm/℃,瞬态响应最大变化量为50 mV,电源抑制大于71 dB@1 kHz,工作电压范围5 V~24 V,输出电压值为3.3 V;tt(渡越时间)模型下,工作电压为18 V 时,对大功率音频功放进行系统仿真,LDO 表现出约为30μs的启动时间,其输出电压值能很好地跟踪负载电流的变化。     

Robustness aware high performance high fan-in domino OR logic design

A novel technique using a keeper with a simultaneous low supply voltage and low body voltage is proposed to improve the overall performance of high fan-in OR gates without modifying the physical dimensions of the keeper. Simulation results of a 16-input domino OR gate using 45 nm CMOS technology show that the proposed technique could trade off between a high power/speed efficient operation and the robustness to noise effectively.Also, a Monte Carlo analysis indicates that the proposed domino OR gate is more robust to parameter variation compared to a conventional domino OR gate.     

高频下保持高输出阻抗的双极电流源

基于仪器和运算放大器的传统电流源和电压/电流转换器在低频下提供很高的输出阻抗,这是因为放大器具有良好的低频CMRR(共模抑制比)。在较高频率下,降低的CMRR、固有的输出电容、转换率的局限性阻止了高质量电流源的实现。     

宽带高线性高隔离无源双平衡混频器

基于InGap/GaAs HBT工艺设计了一款宽带无源双平衡混频器,针对双平衡混频器射频中频交叠及射频到中频端口隔离度差的问题,采用了双混频环+新型滤波补偿网络的结构,不仅提高了隔离度和线性度,同时扩宽了带宽,改善了混频器整体性能.射频、本振频率为1.5～5.0 GHz,射频功率为-10 dBm,本振功率为13 dBm...     

高频预电离在高气压脉冲放电中的应用研究

本文介绍了高频预电离在高气压脉冲放电中的研究结果。从理论与实验上，分析了高频预电离的有关特性，并研究了其对高气压脉冲放电的影响。     

大功率LED高低温特性

在线测量了从－30至100度InGaN和AlGaInP大功率LED的各参数,拟合了两种LED正向压降、相对光强、波长、谱宽和温度的曲线,分析了两种LED参数变化的原因和这些变化对应用的影响。温度对大功率LED的性能和应用都有很大影响,低温时,应考虑正向压降的增大和波长的蓝移,高温时,应考虑光强的下降和波长的红移     

高速高机动弱小目标检测方法研究

本文针对高速高机动弱小目标检测中的距离走动和多普勒走动问题,提出一种多普勒频率补偿加尺度变换的目标检测方法.首先通过多普勒频率估计构建多普勒频率补偿函数,消除速度引起距离走动的影响,其次采用尺度变换方法消除多普勒调频率的影响,从而使积累时间不再受目标运动的限制.该方法无需多普勒调频率估计,解决了传统弱小目标检测方法中多普勒调频率估计准确性问题.在进行多普勒频率估计时,提出一种无模糊多普勒频率估计方法,该方法避免了模糊因子估计,大大减小了计算量,同时降低了对输入信噪比的要求,且有利于多目标情况.仿真结果验证了所提方法大大提高了高速高机动弱小目标的检测性能.     

Material requirements for high voltage, high power IGBT devices

The two basic package types of current IGBT modules, which evolved from opposing requirements of traction and power transmission applications, are presented. It is shown that reliability and lifetime aspects given by traction puts most stringent limitations on the choice of materials at given cost targets. The materials used today for high power packaging and the future developments of high power IGBT-packages are discussed.     

Analog multiplication at high frequencies with a high dynamic range

An analog multiplier has been constructed by means of field-effect transistors. The multiplier has a dynamic range higher than 80 dB and a frequency response that is flat to within 0.7 dB from 50 to 70 Mhz. This device would be very useful in applications where both inputs may vary by 40 dB or more.     

具有高特征温度的808 nm大功率半导体激光器

研制出利用液相外延方法生长808 nm InGaAsP/GaAs分别限制单量子阱激光器,其室温连续输出功率达到4 W,室温工作的特征温度达到218 K.     

Very high speed and high capacity packet switching for broadbandISDN

The authors discuss and propose a very-high-speed and high-capacity packet-switching (HPS) architecture for a future broadband ISDN (integrated-services digital network). The HPS network accommodates various communication services, such as voice, high-speed data, high-speed still picture, and video services. The proposed architecture has three significant principles: a high-speed oriented simple network protocol, separation of signaling and network control from data transfer, and hardware switching. These principles provide fast- and high-throughput transmission for data packets and reliable transmission and processing for call-control packets. The HPS protocol structure is addressed, which provides high flexibility for various communications services as well as high-speed capability. A 3-Gb/s capacity and building-block-structured packet-switching system architecture, using bus- and loop-type switch fabric, is also presented     

优化高电压IGBT造就高效率太阳能逆变器

随着绿色电力运动势头不减,包括家电、照明和电动工具等应用,以至其他工业用设备都在尽可能地利用太阳能的优点。为了有效地满足这些产品的需求,电源设计师正通过最少数量的器件、高度可靠性和耐用性,以高效率把太阳能源转换成所需的交流或者直流电压。