调制型半导体激光器驱动电路设计

半导体激光器以体积小、质量轻、驱动功率和电流较低、效率高、工作寿命长、可直接调制、易于与各种光电子器件实现光电子集成及与半导体制造技术兼容、可大批量生产等特点得到了广泛的研究与应用,研究和改进激光器驱动电路具有重要的意义。小功率可调谐半导体激光器对驱动电流有很高的要求,驱动电流的微小变化将直接导致其输出光强的波动。为实现半导体激光器的稳定功率输出,基于电流负反馈原理设计包含慢启动和限流保护电路的恒流驱动电路。在电路设计中尽可能利用简单的器件和设计起到改善激光器正常工作的目的。在调制过程中分别利用运放与三极管的不同特性设计出了低频低失真和高频开关调制电路。利用两级放大负反馈原理进行反馈电流的调整,降低闭环带宽,增强了闭环负反馈的稳定性。     

三代半导体功率器件的特点与应用分析

以S i双极型功率晶体管为代表的第一代半导体功率器件和以GaAs场效应晶体管为代表的第二代半导体功率器件为雷达发射机的大规模固态化和可靠性提高做出了贡献。近年来以S iC场效应功率晶体管和GaN高电子迁移率功率晶体管为代表的第三代半导体--宽禁带半导体功率器件具有击穿电压高、功率密度高、输出功率高、工作效率高、工作频率高、瞬时带宽宽、适合在高温环境下工作和抗辐射能力强等优点。人们寄希望于宽禁带半导体功率器件来解决第一代、第二代功率器件的输出功率低、效率低和工作频率有局限性以至于无法满足现代雷达、电子对抗和通信等电子装备需求等方面的问题。文中简要介绍了半导体功率器件的发展背景、发展过程、分类、特点、应用、主要性能参数和几种常用的半导体功率器件;重点叙述了宽禁带半导体功率器件的特点、优势、研究进展和工程应用;对宽禁带半导体功率器件在新一代雷达中的应用前景和要求进行了探讨。     

Microwave and millimeter-wave QWITT diode oscillators

The authors present DC, microwave, and millimeter-wave characteristics of different quantum-well-injection transit-time (QWITT) devices. Small-signal and large-signal device models are used to provide physical design parameters to maximize the output power density at any desired frequency of operation. A peak output power density of 3.5-5 kW/cm² in the frequency range 5-8 GHz has been obtained from a planar QWITT oscillator. This appears to be the highest output power density obtained from any quantum-well oscillator at any frequency. This result also represents the first planar circuit implementation of a quantum-well oscillator. Good qualitative agreement between DC and RF characteristics of QWITT devices and theoretical predictions based on small-signal and large-signal analyses is achieved. The device efficiency has been increased from 3% to 5% by optimizing the design of the drift region in the device through the use of a doping spike with optimized concentration, without compromising the output power at X -band. Self-oscillating QWITT diode mixers are also demonstrated at X-band in both waveguide and planar circuits. The self-oscillating mixer exhibits a conversion gain of about 10 dB in a narrow bandwidth and a conversion loss of about 5 dB if broadband operation is desired     

A Multicell Linear Power Amplifier for Driving Piezoelectric Loads

A multicell amplifier is developed by connecting floating signal modules in series to drive piezoelectric devices. The amplifier generates a high voltage gain by summing the individual module gains. The bandwidth equals that of a single module. The multicell amplifier provides a means of achieving high power and can divide the total power dissipation among the modules, because each module delivers the same output voltage and current. A prototype circuit that consists of six floating signal modules exhibits precise linear operation over a wide range of input frequencies and capacitive loads. The circuit provides a plusmn 200-V output swing with a corner frequency of around 100 kHz at a driving capacitive load of 0.1 muF. The slew rate is as high as 115 V/mus, and the maximum output current is plusmn2.6 A. The practicality and performance of the presented modular implementation concepts were verified by the close match between the simulated and experimental results.     

新型毫米波大功率器件——折叠波导行波管

折叠波导行波管是近年来涌现的一类新型毫米波大功率器件。它具有宽频带和大功率的优点,制造成本低,且可以与微波功率模块（MPM）组合实现小型化;由于紧凑的整体极靴,能对低电压电子注聚焦,因而很适合要求轻重量的场合。折叠波导行波管在短厘米波段和毫米波段具有极好的发展前景。     

W波段扩展互作用速调管的研究

扩展互作用速调管是在大功率速调管的基础上,采用扩展互作用谐振腔技术,扩展其瞬时工作带宽,在毫米波频段能够实现高功率、高效率、高增益和宽频带的一种紧凑型微波真空器件。本文基于空间电荷波理论对多间隙谐振腔电路进行了简要分析,采用PIC三维粒子模拟软件对高频互作用电路进行了粒子模拟与优化。在2π模式工作下,其工作电压为15 kV,电流为0.8 A,中心频率为94.5 GHz时,得到了效率大于8.4%,峰值功率超过2 kW的微波功率输出,-3 dB带宽为1 GHz,增益超过40 dB。该工作对研发高性能扩展互作用速调管,并推动其在国防安全、卫星监测、外层空间小目标跟踪、高分辨率雷达和精确气象监测等领域应用具有重要意义。     

S波段1MW多注速调管的研制进展

介绍了一种S波段多注速调管的研制进展.该管采用19注电子枪,工作电压34 kV,工作电流72 A,研制目标是在7％的相对带宽内输出1 MW脉冲功率,工作比2％.介绍了包括互作用段、电子枪、输出窗在内的主要部件和最终测试结果.     

宽带变压器在压电陶瓷驱动电源中的应用

受高压功率器件的限制,目前市场上压电陶瓷高压驱动电源较少且价格贵。变压器能够实现电压和电流的变换,合理的设计可使其在较宽的频率范围内保持良好的频率响应特性。该文研究了一种基于音频变压器的压电陶瓷高压驱动电源的实现方式,并进行了相关实验,实现了一种空载时-3 dB带宽达4 Hz~380 kHz、输出电压峰 峰值达600 V的驱动电源,可在20 kHz的频率下满负荷驱动2.5 nF的容性负载。     

适合容性负载的高压大功率放大器

设计了一种适合压电陶瓷等容性负载的双极性可调高压大功率线性放大器,它由简单低廉的低压运算放大器、基于功率场效应管(MOSFET)的功率放大级组成主回路,通过电压负反馈构成闭环控制。对电路中各环节的特性进行了分析,并讨论了放大器的性能。该高压放大器在驱动等效电容为60nF的压电陶瓷时,单端到地输出电压为一600～ 600V,电压增益42dB,大信号带宽800Hz,小信号带宽7kHz,充放电电流可达200mA,静态电流可达1．4mA。实验与分析表明,高压直流放大器采用功率场效应管和电压闭环控制后,可拓展放大器通频带,提高放大器输出能力和长时间稳定性。     

Experimental Study and Analysis of an S-Band Multiple-Beam Klystron With 6% Bandwidth

We present experimental results and analyses of an eight-beam five-cavity multiple-beam klystron (MBK) operating at a center frequency of ~3.2 GHz. The device met its performance goals in its first hardware implementation, generating a peak RF output power of 600 kW and a 3-dB bandwidth of ~6%. The circuit was modeled with TESLA, a 2.5-D large-signal klystron/MBK code that was extended to enable simulations of the low- Q multiple-gap cavities used to increase the bandwidth. Details of the model and underlying theory are described, and the simulation results are compared with experimental measurements. The good agreement between the model and the experiment provides a validation for our tools and techniques that will be used in the design of future devices.     

Wide-Band Gallium Arsenide Power MESFET Amplifiers

The performance, with emphasis on wide bandwidth, that can be expected of linear medium power GaAs microwave MESFET (metal semiconductor field-effect-transistor) amplifiers is discussed. It starts with measured scattering parameters of devices and proceeds through computer-optimized device modeling, to amplifier circuit designs and performance results. It shows computed and measured octave bandwidth performance and reveals that decade bandwidth is feasible. It discusses single-ended and balanced amplifier design approaches. Some practical designs with performance results are presented, with circuit topologies which are easily realizable in microstrip.     

Moving average filter for spur reduction in subsampling fractional PLLs

A mono-bit digital receiver circuit for instantaneous frequency measurement is presented. The circuit is co-designed with Indium Phosphide Double Heterojunction Bipolar Transistor and complementary metal oxide semiconductor (CMOS) devices. The chip is fabricated by InP/CMOS three-dimensional (3D) heterogeneous integration using the wafer-level bonding technique. The measurable signal frequency within?+?15 to???25 dBm power is up to 7.5 GHz with a 14-GHz clock. Compared to an integrated circuit (IC) with a traditional InP or CMOS technologies, the proposed chip could benefit from both InP and CMOS technology. In the heterogeneous integration, InP devices provide high operating frequency, broad signal bandwidth, and large input signal dynamic range, while CMOS devices achieve complex function with low power consumption. In this way, the system FoM is improved for a mono-bit digital receiver while the system power consumption is kept the same. This work also shows the great potential of the 3D heterogeneous integration for the high-performance mixed-signal and multifunction radio-frequency ICs.

     

便携式压电微型泵驱动电源的研制

根据用于烈性药物输注的便携式压电微型泵的使用要求,研制了压电陶瓷驱动器的驱动电源。驱动电源以3 V锂离子钮扣电池供电,通过DC/DC电路和逆变电路为压电陶瓷驱动器提供高的输出电压(200 V,峰-峰值),具有频率可调,体积小,质量轻,功耗低,安全可靠,便于控制的特点。实验表明,驱动电源能满足压电微型泵的使用要求,也适用于以逆压电效应为基本原理的微小压电器件的动态应用。     

Broad-band injected-beam crossed-field amplifiers

The design and operation of injected-beam-crossed-field amplifiers, which provide efficient amplification over octave frequency bands with grid control in compact PM Focused format, are described. Dielectric supported meander lines, which are used to provide the low-dispersion and high-interaction impedance required to achieve octave bandwidth, are detailed. Relationships between space charge, gain factor, beam impedance, circuit loss, and circuit dimensions are derived for design optimization. An electron gun with a negative grid, which provides noise suppression, as well as a nonintercepting current control electrode, is shown to be effective in controlling the beam current continuously from zero to full operating value. Operating characteristics of production CFA's, providing 1 kW of average power in pulsed and CW operation and up to 5-kW peak pulsed power, are presented to illustrate the inherent multimode performance which can be achieved with low-voltage grid control.     

A low-voltage line driver for digital signaling interface

This paper describes a CMOS line driver that operates from a 3 V power supply and delivers a peak current of about 100 mA to the load. The novel features of the circuit are high power efficiency, an output pulse shape and amplitude independent of power supply and temperature variations, and the ability to handle abnormal load termination conditions. The circuit has been designed in a 0.9 μm CMOS technology and does not require any low-threshold devices     

A 2.1 μW 80 dB SNR DT ΔΣ modulator for medical implant devices in 65 nm CMOS

This paper presents a simple and robust low-power ΔΣ modulator for accurate ADCs in implantable cardiac rhythm management devices such as pacemakers. Taking advantage of the very low signal bandwidth of 500 Hz which enables high oversampling ratio, the objective is to obtain high SNDR and low power consumption, while limiting the complexity of the modulator to a second-order architecture. Significant power reduction is achieved by utilizing a two-stage load-compensated OTA as well as the low-V_T devices in analog circuits and switches, allowing the modulator to operate at 0.9 V supply. Fabricated in a 65 nm CMOS technology, the modulator achieves 80 dB peak SNR and 76 dB peak SNDR over a 500 Hz signal bandwidth. With a power consumption of 2.1 μW, the modulator obtains 0.4 pJ/step FOM. To the authors’ knowledge, this is the lowest reported FOM, compared to the previously reported second-order modulators for such low-speed applications. The achieved FOM is also comparable to the best reported results from the higher-order ΔΣ modulators.     

MCT与Clustered IGBT在大功率应用中的比较研究

针对两种应用于大功率领域的半导体器件——栅控晶闸管(MCT)和组合式绝缘栅晶体管(CIGBT),采用数值仿真软件进行了比较研究。静态仿真结果表明MCT具有更低的正向压降,只有CIGBT的50%左右,而CIGBT得益于其电流饱和特性,具有更大的短路安全工作区。开关仿真结果表明CIGBT具有比MCT更短的关断时间和更小的关断能量,更适合应用于高频领域。同时研究了MCT和CIGBT在脉冲放电应用中的特性,结果表明MCT具有更大的脉冲峰值电流和更快的电流上升率,并首次论证了脉冲放电过程中器件物理机制的区别。     

一种性能多种重构的高频压控有源电感

提出了一种性能多种重构的高频压控有源电感(HFVCAI).电路主要由第一回转回路、第二回转回路以及调控支路构成,且第一回转回路和第二回转回路并联,调控支路与第一回转回路连接,两个回转回路均配置了外部调控端.通过协同调节3个外部调控端,可对HFVCAI的性能进行3种重构:在高频工作区能够对电感值进行大范围调控,且同时能保...     

GaN 功率器件调制电路在T/R组件中的设计与应用

介绍了一种GaN 功率器件调制电路的设计方法。该调制电路广泛用于T/ R 组件发射链路的大功率 GaN 功放,具有高电压工作、大电流供给以及尖峰电压抑制等功能。文中重点论述了调制电路的原理,指出尖峰电 压抑制功能是实现该调制电路的难点。经仿真分析实现了延时在500 ns 以内、负压检测电平在-4. 2~ -3. 8 V 的关 键指标。最后选用聚四氟乙烯印制板设计出GaN 功率器件调制电路实物,在T/ R 组件中进行了应用验证,测试结果 与仿真结论相符。该调制电路体积小、可靠性高,可用于高功率GaN 功放的设计,具有广阔的工程应用前景。     

Versatile composite amplifier configuration

This paper describes a versatile composite amplifier in which a current feedback amplifier (CFA) drives an operational amplifier (OPA). In the conventional OPA–CFA composite amplifier, an OPA drives a CFA resulting in a composite structure that combines the DC input stability of the OPA and the high speed capability of the CFA. The proposed composite configuration combines different features of the CFA and OPA, specifically the constant bandwidth property of the CFA and the high power and high current output capacity of the OPA. The new circuit is easily implemented in the standard inverting and non-inverting configurations using commercially available devices, and the accuracy and constant bandwidth features were experimentally verified. Local feedback around the associated CFA ensures that the proposed composite amplifier possesses a higher level of bandwidth constancy than a single CFA.