IEEE C62.47-1992 ✓ Most Recent

The purpose of this guide is to describe the electromagnetic threat posed to electronic equipment and subassemblies by actual Electrostatic Discharge (ESD) events from humans and mobile furnishings. This guide organizes existing data on the subject of ESD in order to characterize the ESD surge environment. This guide is not an ESD test standard. An appropriate ESD test standard should be selected for equipment testing ([1], [3], ). The manufacturing, handling, packaging, and transportation of individual electronic components, including integrated circuits, are not discussed, and this guide does not deal with mobile items such as automobiles, aircraft, or other masses of comparable size. ESD results in a sudden transfer of charge between bodies of differing electrostatic potentials. In this guide, the term ESD includes charge transfer whether or not an arc occurs or is perceived. ESD phenomena generate electromagnetic fields over a broad range of frequencies, from direct current (dc) to low gigahertz. The term ESD event includes not only the discharge current, but also the electromagnetic fields and corona effects before and during a discharge. In this guide the intruder is often a human, but it may be any object that is moved, such as a chair, an equipment cart, a vacuum cleaner, or the equipment victim itself, whether or not it is in conductive contact with a human. The equipment victim is usually a fabricated electronic equipment or subassembly and is generally, although not necessarily, at local electrostatic ground potential. The equipment victim may be the receptor to which the discharge takes place from the intruder; less frequently, the equipment victim may be the intruder. Alternatively, the equipment victim may be affected by the electromagnetic fields generated by a discharge between an intruder and a receptor. Receptors and intruders that may not themselves be equipment victims include furniture such as metal chairs, carts, tables and file cabinets, as well as other electronic equipment. This guide discusses and cites references that describe the ways in which a body builds up charge and the characteristics of discharge currents and fields. Descriptions and references are also given for electrical equivalent circuits to be used in understanding and simulating the discharge current between intruder and receptor masses. Publications that are specifically referenced in the text of the guide are listed in the Section , while Section cites additional publications in both ESD and related areas. Most of the work that has been published in connection with actual ESD is related to discharges from humans, usually grasping or in association with a metal object. Far less published data exists for discharges from humans without metal objects, and from mobile furnishings, and virtually no data exists for discharges from human torsos or clothing. For this reason, primary emphasis is placed on discharges from humans with associated metal objects, with some additional material relating to ESDs from mobile furnishings. All discharges are assumed to take place in an air environment. Finally, all of the published time-domain data on which this guide relies were taken using instrumentation with either a 400 MHz or a 1 GHz bandwidth.