ESD辐射场测试研究

测试一直是静电与电磁防护研究的瓶颈.针对ESD辐射场测试问题,提出了能量有效带宽和动态范围有效带宽的概念,并根据IEC61000-4-2标准规定的ESD电流波形,采用数值方法估算了ESD辐射场的带宽以及上升时间对带宽的影响.在此基础上成功研制了带宽为3.5Hz~1GHz(±1.5dB),动态范围60dB,测试灵敏度可调的ESD辐射场测试系统,并实际测试了IEC61000-4-2标准规定的水平和垂直耦合电场.     

IEC 61000-4-2存在问题分析

IEC 61000-4-2规定了静电放电抗扰度试验方法,在实际测试中发现该标准存在两个主要问题,使用不同模拟器对同一产品测试会得到不一致的测试结果,而放电次数偏少使得该标准对数字电路测试的测试结果重复性较差.建议详细规定模拟器放电电流波形参数并增加放电次数.     

传输线理论分析静电放电电流

传输线理论分析了静电放电(ESD)发生器的放电过程,时域有限差分法(FDTD)模拟了放电电流,得到与IEC61000-4-2标准相符合的电流波形,并对影响电流波形的关键因素进行讨论.结果表明,静电放电发生器中电阻和连接线长度影响电流波形的上升时间;连接线的布置影响着电流波形的平滑性;不同的终端负载也对电流峰值有很大影响.该结论为静电放电发生器的设计提供了参考和建议.     

IEC61000-4-2静电放电输出电流测量浅谈

IEC61000 -4 -2规定了放电电流的波形参数和测量方法 ,但没有给出如何将示波器电压测量值转换成电流值的办法。本文主要对此问题进行讨论     

电子设备中的ESD保护设计

介绍了静电放电(ESD)的工作机理以及静电放电给电子元器件所带来的损伤。通过对比压敏电阻与瞬变电压抑制二极管(TVS管)的特点,给出了如何选择ESD保护器件的一些建议。在分析了TVS管的工作原理及关键参数基础上,对TVS管选型标准进行了简要介绍。针对使用TVS管的保护电路,以IEC61000-4-2最高严酷度级别4的环境对电路中的寄生参数进行了分析,提出了优化ESD保护器件性能及PCB保护电路设计时需要注意的事项。以MAX3490E为例指出了集成片上ESD系统芯片的优点。     

新版静电标准对静电放电模拟器的影响

该文依据IEC61000-4—2第2版标准,阐述了新版的静电标准对静电放电模拟器的影响,以及这种静电放电模拟器相应的校准方法。     

静电放电模拟器电路建模分析

从实际的静电放电模拟器结构出发,根据接触放电时静电放电电流的主要特征,考虑到静电模拟器本身、连接线及回路电缆与地平面间产生的分布参数的影响,建立了一个新的静电放电模拟器等效电路模型,并用PSPICE软件对等效电路进行模拟分析,得到了与实测波形基本一致的电流波形.利用该模型讨论了各分布参数对放电电流的影响.结果表明:模拟器体电阻与地间的电感对电流波形影响不大,因此可以忽略,但其与地之间的分布电容对电流波形的低频段有重要影响;连接线分布参数对电流波形的第一峰值及波形光滑度都有影响;回路电缆分布参数主要影响了电流波形中第二个波峰峰值及其位置.     

一种改进的火花放电电流波形

分析了四种现有的火花信号电流拟合波形，在此基础上提出了一种改进的火花放电电流拟合方式。该方式拟合得到的电流波形不仅符合IEC 61000-4-2 标准，而且还具有一定的随机性。在此基础上实现了产生具有随机性和叠加特性的更为接近于真实火花源的火花信号方式。     

ESD防护仿真技术研究

静电放电（ESD）一直是电子产品的重大威胁,严重的还会造成芯片失效。在设计阶段需对芯片受ESD冲击后的耦合情况进行预测评估,并为芯片设计有效的ESD防护,实现系统级高效ESD设计（SEED）成为发展趋势。文章研究了瞬态抑制二极管（TVS）对静电的响应情况,并将TVS分为回滞型与非回滞型,分别建立了SPICE模型。提出了一种新的ESD发生器电路模型和全波模型,所得电流波形与实测数据吻合较好。两种模型的电流特征值与IEC 61000-4-2:2008要求的偏差较小。为复现完整的系统级ESD测试环境提供了支持,也为探索芯片在系统级ESD测试下的行为模式打下基础。     

空气式静电放电的放电特性研究

利用简单的静电放电模拟测试装置对IEC标准规定的空气式静电放电的放电特性进行了研究.对放电电流的上升时间、峰值、自制金属半圆环上的耦合电压峰-峰值进行了测量,并用数字存储示波器记录了放电电流和耦合电压的波形.在较宽范围的电压电平和正负电压极性上进行了空气放电.对空气式静电放电的重复性、频谱特性和耦合特性等进行了分析.对空气式静电放电的放电特性研究可为静电放电抗扰度试验方法提供参考.     

On the uncertainty in the current waveform measurement of an ESDgenerator

The uncertainty in the current waveform measurement of an electrostatic discharge (ESD) generator is evaluated. The measurands are the current amplitude and the rise time of the output current waveform of the ESD generator. An intuitively simple model is proposed to evaluate the uncertainty in the current amplitude measurement. Type A and Type B evaluations for all contributions to the measurement uncertainty are performed to obtain the combined standard uncertainty. The evaluated expanded uncertainty (95.5% confidence level) of the current amplitude and the rise time at ESD voltages of 2, 4, 6, and 8 kV are within the specification of IEC 61000-4-2. The results show that the uncertainty in the current amplitude measurement stems from the voltage reading of the measuring equipment, the difference between the displayed and the actual voltages of the discharge tip of the ESD generator, and the inaccuracy of the delta time measurement of an oscilloscope, whereas the uncertainty in the rise time measurement mainly originates from the measuring equipment     

Characterization of human metal ESD reference discharge event and correlation of generator parameters to failure levels-part II: correlation of generator parameters to failure levels

Most electrostatic discharge (ESD) generators are built in accordance with the IEC 61000-4-2 specifications. It is shown, that the voltage induced in a small loop correlates with the failure level observed in an ESD failure test on the systems comprised of fast CMOS devices, while rise time and derivative of the discharge current did not correlate well. The electric parameters of typical ESD generators and ESD generators that have been modified to reflect the current and field parameters of the human metal reference event are compared and the effect on the failure level of fast CMOS electronics is investigated. The consequences of aligning an ESD standard with the suggestions of the first paper, of this two-paper series, are discussed with respect to reproducibility and test severity.     

静电放电电磁脉冲均匀辐射场模拟

为了研究静电放电电磁脉冲（ESDEMP）的特性,利用传统的静电放电电磁脉冲产生方法,通过静电放电模拟器在静电放电抗扰度试验平台上放电,产生了静电放电电磁脉冲,并测出了静电放电电磁脉冲的时域波形和频谱。在研究电磁脉冲模拟器的基础上,首次通过ESD模拟器和GTEM室的结合,在GTEM室内产生了均匀的、重复性和线性好的ESDEMP。实验表明,用TEMP室、GTEM室等大型装置产生均匀静电放电电磁脉冲辐射场的方案是可行的。     

IEC 61000-4-2:2008静电放电模拟器校准方法的变化

针对IEC61000—4—2：2008中静电放电模拟器的校准参数、校准方法的变化,比较了其与2001版本的差别。阐明了2008版标准中用于校准静电放电模拟器脉冲参数的靶型适配器的结构、电参数的重大修改和严格技术要求。最后,详细介绍了靶型适配器的校准框图、校准设备和校准方法。     

Analysis of reliability and optimization of ESD protection devices supported by modeling and simulation

An analysis of electrostatic discharge (ESD) protection structures supported by advanced 2-D mixed mode electro-thermal device and circuit simulation with calibrated electro-physical models to increase the reliability of protected IC’s is presented. The critical temperature as a criterion of device destruction is defined and experimentally verified. Numerical simulation and visualization of the internal electro-physical properties of the analyzed structures during a very short ESD pulse considerably improved the understanding of their physical behavior and contributes to a proper design and optimization of doping and geometry of the analyzed ESD protection devices. The analyzed devices are designed as protection against Human Body Model (HBM) and International Electromechanical Commission model (IEC) 61000-4-2 with very high robustness. The obtained results are shown on two examples. Modification of the device layout by splitting the cathode contact of the ESD diode into two parts allowing area reduction with improved electrical characteristics is the subject of the first example. The influence of doping fluctuations on the device robustness is presented in the second example. Different triggering and failure mechanisms of the diode and transistor structure during HBM and IEC pulse are presented.     

Characterization of human Metal ESD reference discharge event and correlation of generator parameters to failure levels-part I: reference event

Electrostatic discharge (ESD) generators are used for testing the robustness of electronics toward ESD. Most generators are built in accordance with the IEC 61000-4-2 specifications. Using only a few parameters, this standard specifies the peak current, the rise time and the falling edge. Lacking a transient field specification, test results vary depending on which generator is used, even if the currents are quite similar. Such a specification is needed to improve the test repeatability. As for the current, the specification should be based on a reference human metal ESD event. While keeping the presently set peak current and rise time values, such a reference ESD (5 kV, 850-/spl mu/m arc length) is identified and specifications for current derivative, fields, and induced voltages are derived. The reference event parameters are compared to typical ESD generators.