Frequency-Domain Measurement Method for the Analysis of ESD Generators and Coupling

The electrostatic discharge (ESD) generator calibration described in IEC 61000-4-2 (2008) only specifies contact mode discharge waveforms for the discharge-into-ground scenario. However, the actual device under test input impedance often differs from a short. To study the effect of different load impedances, a test method for ESD generator discharge under different load impedances is proposed. The method only slightly modifies the present calibration setup. The data show that the peak current variation between different brands of ESD generators for nonshorted load impedances is within the tolerance range given by the standard for the peak current. On the other hand, when performing system-efficient ESD design simulations, the load impedance seen by the ESD generator models is also different than a short. Therefore, the discharge current of a variety of ESD generator models is simulated with different load impedances and compared with ESD generator measurement results, which allows the selection of a suitable ESD generator model.

The aim of this paper is to investigate the transient magnetic field radiating by electrostatic discharge (ESD) generators. Near field measurements have been conducted, a few centimeters far away from the discharge point (Pellegrini target). The Pellegrini target is mounted on the centre of a grounded metal plane, inside an anechoic chamber. The measurements were carried out to three different directions in relation to the discharge point. The experimental data show that each ESD generator produces a different transient magnetic field. Furthermore, additional differences referring to the produced magnetic field produced by each generator are noted, depending on the direction that the measurement is conducted. Finally, comparisons are stated concerning the magnetic field produced by each generator as well as useful conclusions for the decrease of the magnetic field

This paper demonstrates the essential procedures in the Hong Kong Standards and Calibration Laboratory for the calibration of an electrostatic discharge (ESD) generator in accordance with the International Standard IEC 61000-4-2 Edition 2.0 (2008-12) of electromagnetic compatibility. All the required instruments and special precautions to perform the calibration are listed clearly. The performance of an ESD generator has been tested and reported by following the requirement of the standard. The corresponding results, including the waveform parameters of the current discharge pulse and the DC high voltage test of the ESD generator before discharge with different voltages setting, are reported. The measurement uncertainties of the calibration are clearly listed in this paper, and they are evaluated in accordance with the document "Guide to the Expression of Uncertainty in Measurement (GUM)". The expanded measurement uncertainty U, with level of confidence of approximate 95 %probability is used in the calibration.

This paper introduces a methodology to simulate the currents and fields during an air discharge electrostatic discharge (ESD) into a product by combining a linear description of the behavior of the DUT with a nonlinear arc resistance equation. The most commonly used test standard IEC 61000-4-2 requires using contact-mode discharges to metallic surfaces and air-discharge mode to nonconducting surfaces. In the contact mode, an ESD generator is a linear system. In the air-discharge mode, a highly nonlinear arc is a part of the current loop. This paper proposes a method that combines the linear ESD generator full-wave model and the nonlinear arc model to simulate currents and fields in air-discharge mode. Measurements are presented comparing discharge currents and fields for two cases: ESD generator discharges into a ground plane, and ESD generator discharges into a small product.

Electrostatic discharge (ESD) generators are used for testing the robustness of electronics towards ESD. Most 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 comprising fast CMOS devices, while rise time and current derivative of the discharge current did not correlate well. The electric parameters are compared for typical and modified ESD generators and the effect on the failure level of fast CMOS electronics is investigated. The consequences of aligning an ESD standard with the suggestions of this paper are discussed with respect to reproducibility and test severity.

Electrostatic discharge (ESD) is a physical phenomenon that may destroy electronic components due to its high discharge current that may reach a few amperes in just a few ns. However, another major aspect of ESD is the related high-frequency electromagnetic (E/M) fields radiated by the ESD event. The electronic equipment that is affected by the ESD phenomenon is additionally affected by the induced voltages caused by these E/M fields. This is the reason that the current version of the IEC 61000-4-2 on ESD has a special reference to these fields and the measurement setup. Starting with the classical formulation of these fields, this paper reviews the most popular techniques for calculating the ESD electromagnetic fields while also emphasizing the best methods for minimizing computational effort. There is also a separate section for the measurement techniques that have been applied in research works, whose outcomes could be implemented in the next revision of the IEC 61000-4-2. It is extremely important for the next revision to include these measurement setups and the E/M field sensors because the ESD generators should comply with certain values related to the E/M fields they produce.

This paper summarizes the experience of the EMC laboratory of INRiM in the calibration of electrostatic discharge (ESD) generators. A description of the measurement set-up is followed by the calibration result analysis. The goal of this work is to put in evidence some critical aspects involved in the calibration procedure and to suggest future improvement of the measurement set-up.

In this paper, we describe a hybrid circuit and electromagnetic simulation technique for electrostatic discharge (ESD) events. First, we perform the transient simulation of an equivalent circuit of an ESD generator. At the same time, a computational domain without the ESD generator is analyzed by means of the finite-difference time-domain (FDTD) method. The results from the SPICE-like and FDTD simulations are exchanged for each other by using analogy between the circuit theory and electromagnetics. The proposed method can reduce the computational cost significantly because we perform the FDTD simulation only for the reduced domain, which is much smaller than the whole domain. The adequacy of the proposed method is verified by comparing simulation results with measurement results.

Here, a new analytical method, state matrix transform method, is proposed for calculating the descriptions of current waveforms generated by commercial electrostatic discharge (ESD) generators. This method can be used to analyse and design lumped parameter ESD circuits. A relatively simple eight elements ESD circuit model is established and used to predict the current waveform of human-metal ESD events. To calibrate the ESD simulator, a mathematical expression of four exponentials curve for ESD current waveform is given. This careful theoretical study of ESD current waveform calculation makes an innovative contribution to ESD generator circuit simulation and design, and it provides a new mathematical description for ESD sensitivity test.

Applied Electromagnetics and Electromagnetic Compatibility

Experiment with electrostatic discharge(ESD) generator was implemented in two situations of gap state. All discussion in previous literatures on approach speed effect in electrostatic discharge is really the combination of contact mode discharge and air mode discharge because of final collision of electrode with the target. Three kinds of discharge current waveforms are analysed for experiment test results in electrostatic discharge. Approach speed, i.e., moving electrode velocity to the target, only alter charge state on electrode before ESD taking place. The parameters of ESD are affected by special contact electrostatic discharge combination with air discharge.

Electrostatic discharge induced by strong electromagnetic field refers to the electrostatic discharge process of spacecraft surface materials, cables, some special structural parts and other areas with low charging potential induced by strong electromagnetic field. In general, the spacecraft surface low charge potential sensitive area of the electric field is weak, and electron energy is lower than the ionization energy of molecules, atoms, collision ionization probability is low, when the strong electromagnetic field action, stimulate low-pressure gas to produce dense plasma, thereby reducing the discharge threshold and induce the generation of electrostatic charge discharge. The establishment of testing method for electrostatic discharge induced by strong electromagnetic field is the premise of research on law and protection method of electrostatic discharge induced by strong electromagnetic field. At present, there are no experimental conditions for the interaction between strong electromagnetic field and space environment in China. Therefore, this article established the strong electromagnetic radiation environment and space radiation environment at the same time, under the action of induced discharge test system, not only to be able to carry out electrostatic discharge, high power microwave, nuclear electromagnetic pulse, ultra-wideband electromagnetic pulse and continuous wave such as strong electromagnetic field radiation studies, but also need to solve the high vacuum environment at the same time for sample production and discharge, the discharge parameters and the effect of real-time monitoring, etc. For the research on the rules of space equipment of strong electromagnetic field induced electrostatic discharge is of great significance.

If a nongrounded piece of metal is subjected to an electrostatic discharge (ESD), a spark between this metal part and grounded metal parts can occur. This discharge is generally called “secondary ESD.” These secondary ESDs are often very close to the electronic part inside products and, as this paper shows, can have much higher currents and shorter rise times than the original ESD. For that reason, secondary ESD poses a very high risk of causing soft and hard errors in the affected device under test (DUT). A methodology to model the secondary ESD inside a portable electronic product is presented herein. This is a co-simulation model and it combines linear descriptions of the ESD generator and the DUT with the nonlinear spark-arc model and a model for the initiation delay (statistical time lag) of the spark. Measurement results are presented comparing discharge currents and time delays for two cases: secondary discharge between metal rod and ESD target, and inside a portable product.

Electrostatic discharge (ESD) is a source of electromagnetic disturbance. For an ESD immunity test, IEC 61000-4-2 is standardized. In the standard, the air discharge and contact discharge method are described for the application of ESD to equipment under test. Air discharge, which is most common in the field, is a more severe test than contact discharge. Air discharge is dependent on the humidity, the speed of approach to grounded material, the structure of the ESD generator, and so on. An ESD event while charged material approaches grounded material has a more significant effect on electronic equipment than an ESD event from stationary charged material with the same charge potential. This peculiar phenomenon is considered because the rise time becomes faster and the peak spark current becomes larger, but is not well understood for reasons such as the difficulty of reproducibility. To promote an understanding of the spark discharge that occurs while a charged material is approaching a grounded material, the effect of change in the time of the charging voltage on the spark discharge from a stationary metal disk was measured. The experiment showed that the spark voltage and peak spark current increased with a change in the time of the charging voltage, and that the amplitude of the spark current spectra also increased with a change in the time of the charging voltage. The experimental results are considered in terms of the sparking resistance formula, and can be explained qualitatively in terms of the increase of spark voltage. 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 173(3): 1–9, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20991

Human-to-metal electrostatic discharge current measurements – Notes on the ESD current waveform