PWMH桥驱动电路SA51及其应用

ＳＡ５１是美国ＡＰＥＸ公司最新推出ＰＷＭＨ桥驱动电路，主要用于直流电机伺服电路和Ｄ类开关放大器，本文拟介绍其主要特性，结构功能，使用注意事项及其典型应用电路。     

恒温电路设计中温度传感器的选择与应用

主要介绍恒温加热电路的设计，温度传感器选择和在恒温电路中的作用。     

信号波形合成实验电路设计

本文设计了一个用于演示波形合成的实验电路，其主要包括方波振荡电路、分频电路、滤波及调理电路和移相加法电路等。实验结果表明：所设计的电路产生的相应幅度的10kHz，30kHz和50kHz正弦波分别作为基波和3次谐波和5次谐波可以合成一个近似方波，并与理论相符。     

立体声录音座录放音电路的检修（1）

放音电路一般由双卡放音输入电路和放音前置均衡放大器、后级放大电路等组成；放音电路的主要作用是将磁头信号进行放大，从而改善频响，提高音质。下面分绍几种较常见的放音电路。     

基于S3C44BOX的PDA核心设计

基于ARM的嵌入式系统的核心部分包括处理器、存储器、JTAG电路和电源部分。存储器主要由SDRAM、FLASH和EEPROM等组成，本文给出了具体电路。JTAG电路包括复位电路和JTAG接口电路。电源部分采用LDO器件，本文分析了各个模块的耗电情况，并给出了电源设计的方法。     

一种改进的能量回收逻辑电路

文本分析了能量回收电路的功耗组成，指出非绝热损失是能量回收电路的主要功耗能量来源，提出了一种改进的能量回收逻辑电路IERL。IERL电路增加了额外的回收路径，能够显著降低电路的非绝热损失，HSPICE模拟结果表明，IERL电路具有很好的低功耗性能。同时，给出了IERL电路的复杂逻辑门设计与级联方式，用0．8μm DPDM工艺实现了2位IERL全加器电路和两相正弦功率时钟电路。     

基于UC3724／25的功率MOSFET驱动电路的设计和研究

本文介绍了专用驱动芯片组UC3724／3725的主要特点和原理，并对其构成的功率MOSFET驱动电路进行了分析和实验，实验结果表明，该集成驱动电路具有开关速度快，且能满足驱动所需的功率，是一种性能较好的驱动电路。     

基于UC3724／25的功率MOSFET驱动电路的设计和研究

本文介绍了专用驱动芯片组UC3724／3725的主要特点和原理，并对其构成的功率MOSFET驱动电路进行了分析和实验。实验结果表明，该集成驱动电路具有开关速度快，且能满足驱动所需的功率，是一种性能较好的驱动电路。     

车载对讲机的检修原则及注意事项

车载对讲机的检修原则及注意事项赵振强一、检修原则车载对讲机和一般手持对讲机一样都是由以下主要电路组成：电源电路、发射电路、接收电路、逻辑控制电路、频率合成电路等，检修时可按以下顺序进行。１．准确确定故障现象故障现象的确定，主要根据送修者的反映及检修者...     

线性负温度系数温度传感器及其应用

线性负温度系数(NTC)温度传感器是一种线性化输出负温度系数热敏元件，该传感器的主要特点是在工作温度范围内温度一电压为线性关系，对测温电路无需线性化处理就可完成测温或控温电路的设计，简化测温仪表的设计和调试。给出该传感器的主要特性参数，恒流源供电和恒压源供电两种情况下的信号调理电路及与单片机的接口电路。     

电源线滤波器对电子设备EMC影响分析

针对电子设备在电磁兼容(Electromagnetic Compatibility,EMC)测试中遇到的问题,从电源线滤波器内部电路入手,分析了电源线滤波器对电子设备EMC性能的影响。描述了如何根据电子设备内部电路、使用条件,尤其是输入端电路特性,对电源线滤波器的阻抗特性、插入损耗等参数进行正确选择。对于影响电子设备EMC性能的电源线滤波器的安装方法进行了分析、讨论,列举了2个实际测试例子,并对整改措施进行描述和分析。     

Power and stability limitations of resonant tunneling diodes

Stability criteria for resonant tunneling diodes are investigated. Details of how extrinsic elements, such as series inductance and parallel capacitance, affect the stability are presented. A GaAs/AlAs/InGaAs/AlAs/GaAs double-barrier diode is investigated, showing the effect of different modes of low-frequency oscillation and the extrinsic circuit required for stabilization. The effect of device stabilization on high-frequency power generation is described. The main conclusions of the paper are: (1) stable resonant tunneling diode operation is difficult to obtain, and (2) the circuit and device conditions required for stable operation greatly reduce the amount of power that can be produced by these devices     

Design of high-efficiency RF Class-D power amplifier

In this paper, the losses in a Class-D RF switching power amplifier and their frequency dependence are described. The losses analyzed are the switching, conduction, and gate drive losses. A 300 W, 13.56 MHz, Class-D circuit is designed in the traditional manner to illustrate the magnitude of the different types of loss. A circuit using the ZVS equations developed in this paper is designed. An experimental circuit is built using standard IRF540 devices in TO220 packages. That circuit does not meet its performance goals because of the package inductance. A new low inductance half-bridge package is introduced to solve this problem. Techniques for circuit layout and power measurements for RF applications are also presented in the experimental section. A low loss gate drive circuit is also presented using a Class-E circuit to provide the drive power. The experimental results confirm the accuracy of the design equations derived in this paper     

Interleaved soft switching resonant converter with a small input ripple current

ABSTRACT

An interleaved frequency control soft switching converter is studied for solar power or fuel cell power applications. The proposed circuit topology contains two parallel current-fed circuit cells with interleaved pulse-width modulation operation. Thus, the ripple currents at input and output terminals are decreased. In each circuit cell, the proposed current-fed dc-dc converter includes boost circuit and resonant circuit to achieve current ripple-free on low voltage side and less switching losses on active devices. The boost circuit and the resonant circuit have same active devices to decrease power switches. Due to the resonant behaviour, the reverse recovery current loss on secondary diodes is removed. The voltage doubler circuit topology is accomplished on secondary-side to reduce diode counts and conduction loss. The performance and effectiveness of the developed interleaved PWM current-fed converter are verified and confirmed by experiments.     

Adding active clamping and soft switching to boost-flybacksingle-stage isolated power-factor-corrected power supplies

Single-stage isolated power-factor-corrected power supplies (SSIPP) have the attractive features of fast regulation and a single control loop. However, SSIPP circuits also have higher voltage stress and heavier loss (when compared with a normal DC-DC power converter), which severely limit their practical applications. In this paper, the authors propose to add active clamping to SSIPP to recycle the energy trapped in the leakage inductance of their transformer (to keep the switch voltage stress low) and to achieve soft switching of their electronic devices (to further reduce the loss). This arrangement significantly improves the viability of SSIPP for practical applications. The auxiliary active-clamping transistor in the proposed circuit uses the same control/driver circuit as the main switching transistor. Simulations and experimental works verifying the operation of the converter are reported     

中小功率单相全桥节能型谐振极逆变器

中小功率单相全桥逆变器常以金属氧化物半导体场效应晶体管（Metal Oxide Semiconductor Field Effect Transistor,MOSFET）作为开关器件,为实现逆变器在高开关频率下的节能运行,本文提出了一种单相全桥节能型谐振极逆变器拓扑结构,其桥臂上分别并联相同的辅助谐振电路.桥臂上的主开关开通前,其并联的谐振电容的电压能周期性变为零,使主开关完成零电压软开通,可消除MOSFET的容性开通损耗,有利于逆变器的节能运行.本文分析了电路的工作模态,实验结果表明主开关器件处于零电压软切换.因此,该拓扑结构对于研发高性能的中小功率单相全桥逆变器具有参考价值.     

一种多路输出兼做辅助电源的稳压电源设计

线性稳压电源因其设计成熟、成本合理,能满足中小功率电子设备的一般稳压要求,在其基本设计基础上不断的技术改进更拓展了其应用范围.文章阐述了对于多路输出的稳压电源,通过选择一路电压作为主电路的辅助电源,避免了输入电压波动或负载变化对工作状态参数的干扰,维护了主电路放大器独立的工作环境,拓展了输出电路功能又减少了单元电路设计,是对基本设计的一种特色改进.文章中稳压电源的线路分析、核心元件计算,为精确选择或替代元件提供了一定参考价值.     

开关损耗与温升的PLECS仿真分析

借助仿真分析工具可验证理论分析的正确性,还能为实验研究过程提供有价值的经验。为培养知识全面型人才,电气工程专业学生应学会使用电磁热多域仿真软件,分析电力电子变换电路控制系统与功率器件的电、热特性。本文以双边LCC谐振网络无线输电系统中SiC功率MOSFET、逆导型开关（RC-IGBT）为例,基于热传导理论和连续网络热路模型（Cauer模型）,给出如何采用PLECS进行功率器件的热建模、损耗分析和温升计算。     

基于反激式开关电源电路实现与测试分析

本文实现了开关电源电路的实现,设计采用典型的反激式开关电源结构设计形式,以UC3842作为控制核心器件,运用脉宽调制的基本原理,并采用辅助电源供电方式为其供电,有利于增大主电源的输出功率。采用场效应管作为开关器件,其导通和截止速度很快,导通损耗小,为开关电源的高效性能提供保障。同时,电路中辅以过压过流保护电路,为系统的安全工作提供保障,本电路注意改善负载调整率,提高开关电源工作效率,降低开关电源输出纹波电压,降低电磁串扰,达到绿色环保的目的。输出电压可调,使其可适用于不同场合。     

Push-pull operation of transferred-electron oscillators

Push-pull circuit configurations for GaAs transferred-electron oscillators are described. C.W. X band and pulsed L band devices have been operated in such circuits and have shown as much as 50% increase in output power compared with the sum of the powers obtained from the individual devices.