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Basics of ESD Safety And Data Tracking

What Makes ESD Important?

Electrostatic discharge, more commonly known as ESD, appears in many forms. From lightning bolts to a near-invisible spark when touching a piece of metal, there is no single way to encapsulate all of the different forms of ESD. In many cases, ESD can be felt in the form of a mild shock, usually more irritat- ing than painful. However, when it comes to the world of electronics and manufacturing, this little shock can prove costly.

ESD De � ned

� eld. Before the actual discharge event, the electrostatic charge builds due to an electron imbalance on the surface of the material. This charge can be created in a number of ways, including professional shoes scuff- ing against a particular surface, or certain materials rubbing against each other. This accumulation of electrical charge causes one surface to gain electrons (negative charge) and the other to lose electrons (positive charge). The ESD event brings the electrical charge back into balance by transferring elec- trons via current. An ESD event occurs when an electrostatic charge rapidly transfers between two objects. This transfer is usually caused when two objects with a notable potential difference in electrical charge contact each other. However, ESD events can also happen when two objects close to one another create a highly charged electrostatic

The Dangers of ESD

Static charges can accumulate at almost any stage of a manufacturing process. Any object that moves and is not a perfect conductor is susceptible. For example, imagine a line of parts moving past a plastic window during the manufacturing process. As the parts move, a static charge builds up on the window; when the charge reaches a certain level, it can arc and discharge to a grounded point. If the arc is intense enough, components may be damaged in the process. (See Figure 1.)
Plastic window Static build up Movement of parts Parts Figure 1: Static within a moving manufacturing process