Fully integrated gate drive supply Around Power switches

Main power switches such as metal oxide semiconductor field effect transistors or insulated gate bipolar transistors have reached very high performances from an electrical point of view. If their electrical characteristics are getting closer to physical limits, there is still a lot to do to improve their functionalities. The paper presents the monolithic integration of a gate drive power supply with the power switch to be driven. The operating principle is discussed to demonstrate that all needed components for this function can be integrated with the power switch. It is also demonstrated that the solution does not require any main power switch technological process modification-leading to a cost effective solution. Modeling and analysis comments are provided in order to clarify and to present operating principles and possible design constraints. Finally, the realization itself is presented. Prototypes are used to highlight the interest of such function.     

A novel optical bistable multiple-quantum-well phase modulator

The authors present a new type of optically bistable phase modulator utilizing a self electrooptic effect device (SEED) integrated with an electrooptic wavelength modulator. An electrically bistable SEED, operating on the principle of the quantum-confined Stark effect, controls the bias voltage across an electrooptic waveguide phase modulator to produce optical bistability. A control signal at 0.848 μm, corresponding to the first electron to heavy hole exciton transition in GaAs/AlGaAs multiple-quantum-well is used to switch 1.152 μm light propagating through a waveguide in a direction normal to the control beam     

Resistive Switching Mechanism in ZnxCd1 − xS Nonvolatile Memory Devices

Nonvolatile information storage devices based on an abrupt resistance switch when an electric bias is applied are very attractive for future memory applications. Recently, such a resistance switch was described in ferroelectric Zn_xCd_1-xS, but the mechanism of switching remains controversial. Here, we present results that elucidate the mechanism, showing that a metal needs to be easily oxidized and is capable of diffusing into the ZnCdS film as a cation impurity forming a filamentary metallic conduction path     

Two-dimensional GaAs photonic switch array with direct gain andhigh contrast

The fabrication and design of a 4×4 surface-normal reflection photonic switch array, with an operating principle based on the change of the gain coefficient in GaAs, is described. A 3-μm-thick GaAs active layer and carrier confinement layers are sandwiched between a semiconductor multilayer reflector and an antireflection window. The beryllium ion implantation technique is used to make a narrow current path to reduce the operation current. Each photonic switch independently realizes direct amplification and absorption of the optical signal. It features an optical gain of 4 dB and a contrast of 9.6 dB, for an applied voltage of 2.2 V. The array has a simple planar structure     

基于可开关桥式耦合结构的介质滤波开关

作为无线通信时分双工子系统的重要元件之一,目前绝大多数已报道的滤波开关是利用微带线结构实现的,然而其较高的损耗已逐渐不能满足通信系统的要求.文中针对介质滤波器提出了一种可开关桥式耦合结构,该耦合结构由印刷电路板上的一部分金属带条和伸入介质腔体内部的两根金属探针构成.将PIN管并联在金属带条上,通过控制PIN管的偏置电压...     

Small–signal analysis of floating–junction transistor switch circuits

In this paper some characteristics of switch circuits using junction transistors are analyzed. The switch properties result from the large changes in small-signal admittance of one junction of a transistor when the bias polarity of the other junction is reversed. The characteristics analyzed include the small-signal, low-frequency conductance and the associated potentials. The circuits are suitable for low level modulators and commutators.     

STM/AFM nano-oxidation process to room-temperature-operatedsingle-electron transistor and other devices

Application of a scanning tunneling microscopy (STM) and an atomic force microscopy (AFM) to electron devices and an optical device are introduced in this paper. Using STM tip/AFM cantilever as a cathode, surfaces of a metal or a semiconductor are oxidized to form a few tens of nanometers-wide oxidized metal line or an oxidized semiconductor line, which works as an energy barrier for an electron. A single-electron transistor (SET), a photoconductive switch, and a high-electron mobility transistor (HEMT) are fabricated using this fabrication process. The fabricated SET operates even at high room temperatures and shows the large Coulomb gap and staircase of 200-mV periods and the large Coulomb oscillation periods of 406 mV. The fabricated photoconductive switch shows a ultra-fast response time, i.e., a full-width at half-maximum response of 380 fs at a bias voltage of 10 V. The drain current of HEMT was controlled by the oxidized semiconductor wire on the channel region formed by this fabrication process     

A High-Linearity Single-Pole-Double-Throw Pseudomorphic HEMT Switch Based on Tunable Field-Plate Voltage Technology

A high-isolation high-linearity GaAs pseudomorphic high-electron mobility transistor single-pole-double-throw microwave switch was developed using a tunable field-plate (FP) bias voltage technology. In this paper, a piece of FP metal was deposited between 0.15-$muhbox{m}$-long gate and drain terminals. An extra FP-induced depletion region was generated to suppress the harmonics of switching associated with off-state operation. When switching into the on-state, the FP switch is associated with an insertion loss similar to that of the standard switch below 6 GHz. However, the isolation performance can be enhanced by 10 dB using an FP technology, which reduces the off-state capacitance that is produced by the extra FP-induced depletion region. The FP provides an additional mechanism to suppress the power of the second- and third-order harmonics in the off-state with slight on-state insertion-loss degradation.      

直流固态功率控制器控制技术

直流固态功率控制器是智能开关装置,采用功率MOS管作为直流负载接通或断开直流电源的开关器件,能够实现过载、短路、超温等保护功能。通过DC-SSPC对直流负载进行远程控制,可随时获知负载的工作模式和运行状态,具备健康诊断和实时监控功能。主要研究了直流固态功率控制器工作原理及主要关键技术,并通过原理样机验证了直流固态功率控制器设计的可行性。     

马赫曾德尔调制器偏压控制技术研究

介绍了马赫曾德尔调制器的工作原理及传输曲线随温度漂移引起偏置工作点改变的现象。理论推导出基于谐波分析的马赫曾德尔调制器偏压工作点稳定控制方法,同时通过导频信号来度量偏压工作点的漂移量。设计出基于FPAG的马赫曾德尔调制器偏压控制硬件模块,通过记录接入该模块前后PIN光电二极管电压及马赫曾德尔调制器输出光功率的变化情况,最终证实该偏压控制模块可以实现稳定马赫曾德尔调制器工作点的目的。     

On-board baseband switch development using A high speed optical ring

This paper presents work performed at COMSAT Laboratories to develop a prototype on-board baseband switch. The switch design is modular to accommodate different service types, and the architecture features a high-speed optical ring operating at 1 Gb/s to route input (up-link) channels to output (down-link) channels. The switch is inherently a packet switch, but can process either circuit-switched or packet-switched traffic. If the traffic arrives at the satellite in a circuit-switched mode, the input processor packetizes it and passes it on to the switch. The main advantage of the packet approach lies in its simplified control structure. Details of the switch architecture and design, and the status of its implementation, are presented.     

A Polymer‐Electrolyte‐Based Atomic Switch

Studies on a resistive switching memory based on a silver‐ion‐conductive solid polymer electrolyte (SPE) are reported. Simple Ag/SPE/Pt structures containing polyethylene oxide–silver perchlorate complexes exhibit bipolar resistive switching under bias voltage sweeping. The switching behavior depends strongly on the silver perchlorate concentration. From the results of thermal, transport, and electrochemical measurements, it is concluded that the observed switching originates from formation and dissolution of a silver metal filament inside the SPE film caused by electrochemical reactions. This is the first report of an electrochemical “atomic switch” realized using an organic material. The devices also show ON/OFF resistance ratios greater than 10⁵, programming speeds higher than 1 μs, and retention times longer than 1 week. These results suggest that SPE‐based electrochemical devices might be suitable for flexible switch and memory applications.     

Distortion in off-state arsenide MESFET switches

This paper presents the results of an investigation into the origin and level of distortion generated by the off-state gallium arsenide MESFET when used as a microwave semiconductor control element. The results show that the drain-gate and gate-source capacitance nonlinearities generate distortion in the device in its off-state. These nonlinearities, which reflect the capacitance-voltage characteristic of the capacitances, can be reduced in as-fabricated devices by increasing the gate reverse bias voltage. The level of distortion monotonically increases with frequency throughout the usable range of the MESFET when used in a series reflective switch. In an SPDT switch application, where both on and off-state devices are used, the distortion level is relatively constant at frequencies in the vicinity of the gate bias cut-off frequency. The nonlinear off-state model is compared with both a SPICE-based analysis, and with experimental data on a GaAs MESFET SPDT switch. The main conclusions to be drawn from the study are that the dominate distortion generated by a GaAs MESFET used in a switch application occurs in the on-state, and that off-state distortion can be only slightly improved in as-fabricated devices     

光控功率开关BMFET的特性分析与数值模拟

讨论了光驱动ＢＭＦＥＴ作为光控功率开关的工作原理，根据理论分析和计算机模拟讨论了器件结构参数和外加偏置电路与工作特性的关系，为器件优化设计提供依据。     

Novel zero-Voltage-transition PWM DC-DC converters

A new family of zero-voltage-switching (ZVS) pulsewidth-modulated (PWM) converters that uses a new ZVS-PWM switch cell is presented in this paper. Except for the auxiliary switch, all active and passive semiconductor devices in the ZVS-PWM converters operate at ZVS turn ON and turn OFF. The auxiliary switch operates at zero-current-switching (ZCS) turns ON and OFF. Besides operating at constant frequency, these new converters have no overvoltage across the switches and no additional current stress on the main switch in comparison to the hard-switching converter counterpart. Auxiliary components rated at very small current are used. The principle of operation, theoretical analysis, and experimental results of the new ZVS-PWM boost converter, rated 1 kW, and operating at 80 kHz, are provided in this paper to verify the performance of this new family of converters.     

Dynamic SVL and body bias for low leakage power and high performance in CMOS digital circuits

In this article, a new complementary metal oxide semiconductor design scheme called dynamic self-controllable voltage level (DSVL) is proposed. In the proposed scheme, leakage power is controlled by dynamically disconnecting supply to inactive blocks and adjusting body bias to further limit leakage and to maintain performance. Leakage power measurements at 1.8?V, 75°C demonstrate power reduction by 59.4% in case of 1?bit full adder and by 43.0% in case of a chain of four inverters using SVL circuit as a power switch. Furthermore, we achieve leakage power reduction by 94.7% in case of 1?bit full adder and by 91.8% in case of a chain of four inverters using dynamic body bias. The forward body bias of 0.45?V applied in active mode improves the maximum operating frequency by 16% in case of 1?bit full adder and 5.55% in case of a chain of inverters. Analysis shows that additional benefits of using the DSVL and body bias include high performance, low leakage power consumption in sleep mode, single threshold implementation and state retention even in standby mode.     

Photonic crystal-based permutation switch for optical networks

We present, for the first time, the design of a low-cross talk scalable permutation switch employing photonic crystal ring resonators in an optical network. Through this novel approach, the transition between different states of the \(2 \times 2\) optical switch, as the basic element, is achieved by applying different operating wavelengths. Subsequently, the shuffling mechanisms in \(3 \times 3\) and \(4 \times 4\) optical networks are realized by controlling the position of photonics crystal ring resonators. Lowest cross talk levels of 6 and 5% are obtained for “bar” and “cross” switching states, respectively.     

用光导开关产生高压、高功率超快电脉冲

基于半导体材料的光导效应,设计并制做光导开关,在偏压为4000V,负载电阻Z0为50Ω时,用脉宽为～12ns的激光脉冲辐照光导开关,得到脉宽为～16ns,峰值电压为～1.8kV,峰值功率为～65kW的电脉冲,本文并对光导开关的技术关键进行了分析。     

New family of zero-current-switching PWM converters using a new zero-current-switching PWM auxiliary circuit

A new family of zero-current-switching (ZCS) pulsewidth-modulation (PWM) converters using a new ZCS-PWM auxiliary circuit is presented in this paper. The main switch and auxiliary switch operate at ZCS turn-on and turn-off, and the all-passive semiconductor devices in the ZCS-PWM converters operate at zero-voltage-switching (ZVS) turn-on and turn-off. Besides operating at constant frequency and reducing commutation losses, these new converters have no additional current stress and conduction loss in the main switch in comparison to the hard-switching converter counterpart. The PWM switch model and state-space averaging approach is used to estimate and examine the steady-state and dynamic character of the system. The new family of ZCS-PWM converters is suitable for high-power applications using insulated gate bipolar transistors (IGBTs). The principle of operation, theoretical analysis, and experimental results of the new ZCS-PWM boost converter, rated 1.6 kW and operating at 30 kHz, are provided in this paper to verify the performance of this new family of converters.     

Probing the minority-carrier quasi-Fermi level in epitaxial Schottky-barrier diodes

An experimental technique for probing the minority-carrier quasi-Fermi level in epitaxial Schottky-barrier diodes has been developed and verified for the first time. The technique uses a novel self-aligned floating guard ring as a probe for the hole quasi-Fermi level in the quasi-neutral epitaxial region of an epitaxial Schottky-barrier diode [1]. The anode of the Schottky diode is separated from the guard ring by a thin sidewall oxide, thereby allowing the guard ring to be electrically isolated from the anode. It is shown through both simple physical arguments and two-dimensional numerical simulations that the potential on the floating guard ring assumes the value of the plateau of constant-hole quasi-Fermi level in the quasi-neutral epitaxial region under the anode when bias is applied to the anode. Experimental measurements on both low- and high-barrier Schottky diodes agree very well with two-dimensional numerical simulations as well as computer simulations of a detailed equivalent-circuit model. The result provides direct evidence of the fact that the hold quasi-Fermi level in the silicon does not line up with the metal level at large forward bias and indicates that Schottky-barrier diodes can be scaled further than previously predicted.