串行时钟芯片DS1202

串行时钟芯片ＤＳ１２０２空军电讯工程学院景志宏１、引言ＤＳ１２０２是ＤＡＬＬＡＳ公司时钟芯片中开发较早、价格便宜的一种，后来推出的许多产品的内核基本上都是ＤＳＩ２０２，另外再附加一些其它电路（如掉电保护电路、锂电池、ＳＲＡＭ、定时器、晶振等），而且本...     

高性能低泄漏CMOS模拟多路开关

文章介绍了高性能的ＭＡＸ３０６／ＭＡＸ３０７／ＭＡＸ３０８／ＭＡＸ３０９及低泄漏的ＭＡＸ３３８／ＭＡＸ３３９的工作原理及性能特点。     

可校准低漂移的4.096V／5V／10V电压基准

文章介绍了ＭＡＸＩＭ公司生产的电压基准芯片ＭＡＸ６７６／ＭＡＸ６７７／ＭＡＸ６７８的原理与应用     

精品展台

精品展台半导体和ＩＣＣＭＯＳ模拟开关适用低失真系统Ｍａｘｉ公司最新推出低导通电阻ＣＭＯＳ单刀单掷开关系列产品,型号为ＭＡＸ４５８０、ＭＡＸ４５９０和ＭＡＸ４６００～ＭＡＸ４６０９,其中ＭＡＸ４６０４～ＭＡＸ４６０６导通电阻为５;ＭＡＸ４６０７～ＭＡＸ...     

MAX118及其在PCM遥测编码器中的应用

文章介绍了ＭＡＸＩＭ公司的ＭＡＸ１１８Ａ／Ｄ转换器，针对ＰＣＭ遥测的特点，给出了一种ＭＡＸ１１８与ＰＬＤ的接口方式，构成了ＭＡＸ１１８的最小应用系统。     

低功率转换速率限定的RS—485／RS—422收发器

本章介绍了ＭＡＸ４８１／ＭＡＸ４８３／ＭＡＸ４８５／ＭＡＸ４８７－ＭＡＸ４９１、ＲＳ－４８５和ＲＳ－４２２通信收发器的特点与性能。     

八路13位数模转换器MAX547的原理及应用

ＭＡＸ５４７是美国ＭＡＸＩＭ公司生产的Ｄ／Ａ转换器。该转换器精度高,意境蛞恙微机接口方便,适合于工业过程的自动化控制。文中简要介绍了ＭＡＸ５４７的工作原理,并给出了ＭＡＸ５４７与８０５１单片机的接口电路。     

带静电保护的RS—485／RS—422接口芯片

文章介绍了能抗±１５ｋＶ静电电荷冲击且具有转换速率限制低功耗的ＲＳ－４８５／ＲＳ－４２２收发器ＨＡＸ４８１Ｅ／ＭＡＸ４８３Ｅ／ＭＡＸ４８５Ｅ／ＭＡＸ４８７Ｅ～ＭＡＸ４９１Ｅ／ＭＡＸ１４８７Ｅ的性能特点与应用。     

高速视频多路器／放大器MAX440和MAX441

文章介绍了ＭＡＸＩＭ公司的高速视频多路器／放大器ＭＡＸ４４０和ＭＡＸ４４１的特点、原理、设计与应用。     

低压差线性稳压器MAX603/MAX604及其应用

１ＭＡＸ６０３／ＭＡＸ６０４的功能特点ＭＡＸ６０３／ＭＡＸ６０４是ＭＡＸＩＭ公司生产的低压差线性稳压器 ,具有预置５Ｖ(ＭＡＸ６０３)／３．３Ｖ(ＭＡＸ６０４)或可调两种输出方式 ,其输出电流可达５００ｍＡ。ＭＡＸ６０３在５Ｖ／５００ｍＡ输出时的压差为３２０ｍＶ,在５Ｖ／２００ｍＡ输出时的压差为１３０ｍＶ;ＭＡＸ６０４在３．３Ｖ／２００ｍＡ输出时压差为２４０ｍＶ。这两款器件的功耗很低 ,静态电流典型值为１５μＡ ,最大为３５μＡ ,关断模式下的最大电流只有２μＡ。同时 ,还可以用电阻对其输出电压进行调节 ,其输出电…     

Novel topologies for DC-DC converter with PWM control

Two topologies for the buck converter are presented. The first converter consists of two active switches whereas the second converter, derived from the parent twoswitch converter, consists of only one active switch. The main feature of this new converter is the ability to operate at a constant switching frequency using a simple PWM control. The design of the gate circuit is simplified as there is only one switch. The converter has a good efficiency, as is proved by the experimental results. The operation of the parent two-switch converter, from which the new single-switch converter is derived, is also presented to gain insight into the design of the new converter.     

Watkins-Johnson converter completes tapped inductor converter matrix

The Watkins-Johnson converter has been identified as belonging to the tapped inductor converter families extending once more the matrix of DC-DC converter topologies. This converter is analysed in terms of the tap position and the switch duty cycle and its operation as a rail-to-tap buck converter is verified.     

基于LM5025的有源箝位反激变换器的前馈控制

在有源箝位反激变换器负载基本恒定的情况下采用前馈控制既可以减小变换器体积,又可降低变换器的成本。文中在分析有源箝位反激变换器工作原理的基础上,结合LM5025器件的前馈控制特性,深入研究了基于LM5025的有源箝位反激变换器前馈控制的实现方案,设计了前馈控制电路的参数,完成了有源前馈反激变换器电路设计。在此基础上进行了实验研究,实验结果证明了有源箝位反激变换器前馈控制的有效性和实用性。     

矩阵变换器的间接空间矢量控制

矩阵变换器是一种新型的电力电子技术,具有能量可双向流通,可产生正弦输入电流和输出电压以及输入功率角可调等优点。文章基于矩阵变换器空间矢量调制法,分析虚拟整流器和逆变器的空间矢量调制,综合两个过程,得到一种直接的交-交变换器,利用MATLAB的仿真模块组建成矩阵变换器的仿真模型。仿真结果验证了空间矢量调制策略的有效性,矩阵变换器的优越性。     

带辅助网络的ZVS PWM全桥三电平直流变换器

提出了一种带辅助网络的ZVS PWM全桥三电平直流变换器,很好地解决了ZVS PWM移相全桥三电平变换器中滞后桥臂不容易实现软开关的问题,同时具有开关管电压应力小的特点。加入辅助网络后可以减小谐振电感,达到降低占空比丢失目的。文章分析了变换器的原理,最后通过对一个输出400V,10A的变换器的仿真进行了验证。     

On configurable oversampled A/D converters

An oversampled A/D (analog-to-digital) converter that can be configured as either a sigma-delta converter or an incremental converter is presented. This is an oversampled instrumentation converter that cancels offset and 1/f noise. The converter architecture is based on a mixed analog-digital integrator (MADI) concept. This concept is shown to lead to a very simple and modular architecture. The implemented converter also allows selection of the converter order and the decimation factor in order to find the best tradeoff between resolution, conversion time or bandwidth, and power consumption. As the converter architecture is completely modular, it can rapidly be tailored for a specific application with minimized silicon area. The circuit achieves a resolution of 16 b on a range of ±650 mV and compensates the offset and the even-order harmonics to a nonobservable level     

An isolated bridgeless AC-DC PFC converter using a LC resonant voltage doubler rectifier

This paper proposed an isolated bridgeless AC–DC power factor correction (PFC) converter using a LC resonant voltage doubler rectifier. The proposed converter is based on isolated conventional single-ended primary inductance converter (SEPIC) PFC converter. The conduction loss of rectification is reduced than a conventional one because the proposed converter is designed to eliminate a full-bridge rectifier at an input stage. Moreover, for zero-current switching (ZCS) operation and low voltage stresses of output diodes, the secondary of the proposed converter is designed as voltage doubler with a LC resonant tank. Additionally, an input–output electrical isolation is provided for safety standard. In conclusion, high power factor is achieved and efficiency is improved. The operational principles, steady-state analysis and design equations of the proposed converter are described in detail. Experimental results from a 60 W prototype at a constant switching frequency 100 kHz are presented to verify the performance of the proposed converter.     

XGM波长变换器网络的性能分析

目前对有限范围波长变换器的研究或者是针对能变换到较长和较短波长的FWM(SOA(Semiconductor Optical Amplifier) in Four-Wave Mixing,基于半导体光放大器的四波混合)波长变换器的,或者是针对具有卷绕(Wraprounds)功能的变换器.本文研究了只具有单边变换且不具有卷绕的XGM(SOA(Semiconductor Optical Amplifier) in Cross-Gain Modulation,基于半导体光放大器的交叉增益调制)有限范围波长变换器对网络性能的影响,从网络的阻塞率方面比较了FWM与XGM波长变换器对网络性能的影响.研究结果表明,XGM波长变换器的性能虽然只相当于具有10-20%左右变换范围的FWM波长变换器,但较无波长变换器网络的性能已经有了较大的改善,同时与全范围波长变换器网络的性能相差并不太远.     

Quasi-multi-pulse voltage source converter design with two control degrees of freedom

In this article, the design details of a quasi-multi-pulse voltage source converter (VSC) switched at line frequency of 50 Hz are given in a step-by-step process. The proposed converter is comprised of four 12-pulse converter units, which is suitable for the simulation of single-/multi-converter flexible alternating current transmission system devices as well as high voltage direct current systems operating at the transmission level. The magnetic interface of the converter is originally designed with given all parameters for 100 MVA operation. The so-called two-angle control method is adopted to control the voltage magnitude and the phase angle of the converter independently. PSCAD simulation results verify both four-quadrant converter operation and closed-loop control of the converter operated as static synchronous compensator (STATCOM).     

Transformer secondary leakage inductance based ZVS dual bridge DC/DC converter

A novel zero voltage switching (ZVS) dual bridge dc/dc converter is presented. The proposed converter is composed of two dual-transistor-forward converter, coupled with a single high frequency transformer. ZVS is realized by introducing a proper leakage inductance to the secondary of the high frequency isolation transformer with a corporation of a designed pulse-width modulation control. Operation principle and ZVS condition of the proposed converter are analyzed. Experimental results obtained from a 3.2-kW prototype are given. Extensions of the proposed converter topologies and experimental results of one extension converter are presented.