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关键词： MOSFET   通信设备   IP电话   直流/直流转换器   用户线路   Ring   脉冲电流   电源开关  

摘要： Diodes公司推出专为IP电话（VoIP）通信开发的新型60VN沟道器件，扩展了其MOSFET产品系列。新型DiodesDMN60xx系列专为处理产生正极线和负极线换行线路馈电（Tipand Ring Linefeeds）所需的高脉冲电流，以及抵挡电源开关时引起的雪崩能量而设计。该器件能够满足基于变压器的用户线路接口电路（SLIC）直流／直流转换器对基本切换功能的严格要求。

关键词： LED驱动器   切换式   调光技术   LED照明   设备数量   电路装置   受控电源   节省能源  

摘要： 简介 在LED照明设备数量增长的趋势下,提供给LED受控电源的集成电路装置不断推陈出新。如何节省能源是目前全球的重要议题,而耗电的线性电流源早已不符合这项要求,因此切换式LED驱动器取而代之成为业界标准。

关键词： Radiotherapy   Peripheral   dose   Metal   oxide   semiconductor   field   effect   transistor   Dosimeter  

摘要： AIM:To study the peripheral dose(PD) from highenergy photon beams in radiotherapy using the metal oxide semiconductor field effect transistor(MOSFET) dose verification ***:The radiation dose absorbed by the MOSFET detector was calculated taking into account the manufacturer's Correction Factor,the Calibration Factor and the threshold voltage *** measurements were carried out for three different field sizes(5 cm×5 cm,10 cm×10 cm and 15 cm×15 cm) and for various depths with the source to surface distance set at 100 *** measurements were realized on the central axis and then at distances(1 to 18 cm) parallel to the edge of the field,and were expressed as the percentage PD(% PD) with respect to the maximum dose(dmax).The accuracy of the results was evaluated with respect to a calibrated 0.3 cm3 ionization *** reproducibility was expressed in terms of standard deviation(s) and coefficient of ***:% PD is higher near the phantom surface and drops to a minimum at the depth of dmax,and then tends to become constant with *** scatter radiation is the predominant source of PD and the depth dependence is determined by the attenuation of the primary *** to the field edge,where internal scatter from the phantom dominates,the % PD increases with depth because the ratio of the scatter to primary increases with depth.A few centimeters away from the field,where collimator scatter and leakage dominate,the % PD decreases with depth,due to attenuation by the *** % PD decreases almost exponentially with the increase of distance from the field *** decrease of the % PD is more than 60% and can reach up to 90% as the measurement point departs from the edge of the *** a given distance,the % PD is significantly higher for larger field sizes,due to the increase of the scattering ***,the measured PD obtained with MOSFET is higher than that obtained with an ionization chamber with percentage differences be

关键词： 开关电源   PWM   变压器   MOSFET  

摘要： 光伏并网发电系统中通常使用宽输入范围的开关电源来为低压微控制器、IGBT驱动器以及LCD供电。文中介绍了一种输入范围为120～800V,输出为20V/1A的开关隔离电源的设计方法,从而有效地解决了光伏并网发电系统的供电问题。

关键词： Strained-Si   Heterostructure   2-DEG   Surface   Potential   Regional   Approach  

摘要： In this paper, a charge sheet surface potential based model for strained-Si nMOSFETs is presented and validated with numerical simulation. The model considers sub band splitting in the 2-DEG at the top heterointerface in SiGe layer and also the dependence of electron concentration at heterointerface with the gate oxide. The model is scalable with strained-Si material parameters with physically derived flat-band voltages. An explicit relation for surface potential as a function of terminal voltages is developed. The model is derived from regional charge-based approach, where regional solutions are physically derived. The model gives an accurate description of drain current both in the weak and strong inversion regions of operation. The results obtained from the model developed are benchmarked with commercial numerical device simulator and is found to be in excellent agreement.

关键词： 高效功率变换   双向DC/DC变换   MOSFET  

摘要： 通过分析DC/DC变换器的工作方式,总结出一种应用于串联超级电容器组单体电压动态均衡电路的变换器——高效双向推挽DC/DC变换器,并选择了合适的控制芯片和驱动方式。该方案具有电路拓扑简洁、双向功率流动、控制简单、变换效率高、可靠性高等优点。

关键词： DC/DC稳压器   MOSFET   电感器   器件   封装   阵列   焊盘   内置  

摘要： 凌力尔特公司推出15ADC／DC微型模块（pModule）稳压器LTM4627，该器件重2．6g，采用15mm×15mmLGA（焊盘网格阵列）封装，内置电感器、MOSFET和支持性组件。

关键词： 电阻   影响电阻大小   的因素   欧姆定律  

摘要： 本文以实验为主线，通过演示暗箱实验来引入新课，并引导学生通过实验探究，得出影响电阻大小的因素，最后联系生活实际，加深对知识的理解。

关键词： 配电网潮流   回路电流法   节点编号   优化LU分解   通用算法  

摘要： 针对传统的回路电流潮流算法在进行节点编号时需要添加虚拟支路形成二叉树的缺点,提出一种新的节点编号方法,简化编号过程并提高算法效率;针对回路阻抗矩阵分解算法的优化问题,在原有的只对其中部分元素优化计算的基础上,提出了所有元素均参与优化的回路阻抗矩阵LU分解算法;基于该改进的回路电流法,提出可以计算含有PV节点和弱环网的配电网潮流通用算法,并用PG&E的69节点配电网对算法的有效性进行了验证。

关键词： 光耦合器   测试方式   继电器   元件   利用   测试功能   功能测试   元器件  

摘要： 在场效型元器件（MOSFET）,光耦合元件及继电器的测试方式中,主要是以动作状态是否能正确来决定元件是否工作正常。在ABI4000M的V-I曲线测试功能中,可以针对此3种元件功能测试。接下来,先针对此3种元件的基本结构作说明,