共查询到19条相似文献,搜索用时 109 毫秒
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电桥法测二极管的伏安特性 总被引:1,自引:0,他引:1
电桥法测二极管的伏安特性高伟(安徽芜湖师专物理系241008)电桥法测电阻一种是公认的较精确地测量电阻的方法.本文介绍利用电桥平衡原理测量二极管的伏安特性的电路,能明显提高测量的准确度.一、羽量电路原理二极管伏安特性的坝量是普通物理学的基础实验之一,... 相似文献
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浅谈伏安法测二极管的特性 总被引:1,自引:1,他引:0
高等学校试用的《普通物理实验》一书中,关于伏安法测二极管的特性实验(以下简称伏安特性实验),是通过测出二极管反向饱和电流I_e、正向各种偏压U_D及其对应的电流I_D,算出二极管温度等效电压的倒数(q/kT),再与室温时的理论值比较,让学生了解二极管的正向伏安特性。该实验和一些较能精确测定半导体PN结电流-电压关系的方法相比,不仅具有方法简单,直观性强,数据易处理等优点,而且使学生能够运用普物实验手段,认识半导体二极管这一重要特性,它是大学低年级可以开设的基础实验之一,但是如按课本上的要求测量,误差很大(只有理论值的一半左右),达不到比较满意的效果,本文通过分析误差产生的主要根源,谈谈原实验方案的弊端及改进意见。 相似文献
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伏安特性曲线反映了元件在电路中的基本工作特性.传统的伏安法虽电路简单,但要人工测绘数据点,处理速度慢,误差较大.而示波器则能接受连续变化的信号,并能把它自动描绘成图形,处理速度快,结果直观;且示波器的输入阻抗大,测量精度高.但双通道示波器的X、Y输入公用一个接地点,使得这两路输入的都是对地变化的信号.根据实验教学中普遍使用图1、图2的方法, 相似文献
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本通过对伏安法测二极管特性实验中一个特殊现象的分析,提出了环境电磁波对实验的影响;通过对实验现象的深入分析,能够提高学生观察问题和分析解决问题的能力。 相似文献
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以闪光二号加速器为研究平台,实验研究了前沿80 ns和34 ns脉冲电压下的二极管工作稳定性,通过对比实验结果和数值模拟结果,分析了脉冲前沿对二极管启动时间、阴极发射均匀性和阻抗重复性的影响,探讨了脉冲前沿对平面阴极二极管工作状态的影响机制。实验结果表明:脉冲前沿、二极管启动时间增加时,二极管的阻抗重复性降低;平面阴极易于在中心位置形成强区域发射,等离子体覆盖整个阴极发射面的时间随脉冲前沿增大而增加;屏蔽效应对阴极发射的影响随前沿增加而变大,进而导致阴极表面不均匀强点发射,等离子体运动速度增加,阴极有效发射面积减小,在等离子体运动速度和阴极有效发射面积共同作用下,二极管工作稳定性下降。 相似文献
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Directly extracting both threshold voltage and series resistance from the conductance-voltage curve of an AlGaN/GaN Schottky diode 下载免费PDF全文
An Ni/Au Schottky contact on an AlGaN/GaN heterostructure has been prepared. By using the peak-conductance model, the threshold voltage and the series resistance of the AlGaN/GaN diode are simultaneously extracted from the conductance-voltage (G-V) curve and found to be in good agreement with the ones obtained by using the capacitance-voltage (C-V) curve integration and the plot of dV/d(ln I) versus current I. Thus, a method of directly and simultaneously extracting both the threshold voltage and the series resistance from the conductance-voltage curve for the AlGaN/GaN Schottky diode is developed. 相似文献
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提出了一种高压电源谐振升压倍压电路,该电路由LC谐振电路与整流电路组成。对该电路的工作模式和稳态输出特性进行了分析;建立了该电路的数学模型:以归一化的形式定量描述了稳态输出电压与电流的增益、短路特性和开路特性、输出纹波与电压降、以及器件上的电应力,并分析了电路品质因数、归一化频率和电容比对输出特性的影响;对该电路进行了仿真与实验研究,仿真结果与实验结果具有很好的一致性,验证了数学模型的正确性。与C-W电路的对比研究结果表明:所提出的电路具有输出电压稳定、输出纹波小、短路特性好以及响应速度快的优点,满足高压小电流的应用需求。 相似文献
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Dispersion effect on the current voltage characteristic of AlGaN/GaN high electron mobility transistors 下载免费PDF全文
The current voltage (IV) characteristics are greatly influenced by the dispersion effects in AlGaN/GaN high electron mobility transistors. The direct current (DC) IV and pulsed IV measurements are performed to give a deep investigation into the dispersion effects, which are mainly related to the trap and self-heating mechanisms. The results show that traps play an important role in the kink effects, and high stress can introduce more traps and defects in the device. With the help of the pulsed IV measurements, the trapping effects and self-heating effects can be separated. The impact of time constants on the dispersion effects is also discussed. In order to achieve an accurate static DC IV measurement, the steady state of the bias points must be considered carefully to avoid the dispersion effects. 相似文献
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Two-dimensional models of threshold voltage and subthreshold current for symmetrical double-material double-gate strained Si MOSFETs 下载免费PDF全文
The two-dimensional models for symmetrical double-material double-gate(DM-DG) strained Si(s-Si) metal–oxide semiconductor field effect transistors(MOSFETs) are presented. The surface potential and the surface electric field expressions have been obtained by solving Poisson's equation. The models of threshold voltage and subthreshold current are obtained based on the surface potential expression. The surface potential and the surface electric field are compared with those of single-material double-gate(SM-DG) MOSFETs. The effects of different device parameters on the threshold voltage and the subthreshold current are demonstrated. The analytical models give deep insight into the device parameters design. The analytical results obtained from the proposed models show good matching with the simulation results using DESSIS. 相似文献
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J. H. Han 《Opto-Electronics Review》2008,16(2):185-188
Improvement in frequency bandwidth of a packaged diode laser is investigated by the circuit impedance matching. To overcome
the structural limitation of the electronic package for high frequencies, employing conventional lumped element impedance
matching technique in conjunction with the manipulation of signal path of the package connections showed significant enhancement
for 3-dB bandwidth to more than 6 GHz. 相似文献