Electrostatic Discharge

Electrostatic Discharge (ESD) is the sudden flow of electricity between two unevenly-charged objects. Whether it's a lightning bolt crackling from the sky or the snap you feel as you touch a shopping cart, ESD is a common, natural phenomenon.

ESD occurrences are normally harmless, and modern electronics are pretty shielded/hardened against it. However, there's still a chance that ESD can damage sensitive components, leading to device instability or failure. ESD damage is difficult to trace and diagnose, so it's better to prevent it in the first place.

In normal life, static electricity is the common source of ESD. When you walk across the floor or take off a sweater, charge builds up on you via the triboelectric effect. This charge dissipates through the air—the more humid it is, the faster it dissipates. If you get close to something conductive that's of a lower charge state (often a grounded object), zap! An electrostatic discharge occurs.

When a discharge occurs, you may see a spark, hear a crack, or feel a snap, but it's not guaranteed. On average, you can feel an ESD occurrence only if the discharge exceeds 2,000 volts, but lower voltage ESD can still damage components.

There are two main ways to minimize ESD:

1. Prevent charge from building up in the first place.

2. Create a controlled discharge path to dissipate any residual charge.

Here are some practical ways to minimize ESD:

• Remove rings, watches, and bracelets from your fingers and wrists.
• Keep your new parts in their pink or silver bags until you are ready to install them.
• Place all your bagged new parts on the anti-static mat before you work with them.
• Before starting a repair, discharge yourself by touching a metal fixture. This works because most of the time, fixtures will have a much lower charge potential than you.
• Use an ESD-safe workspace with a grounded anti-static mat and anti-static wrist strap.
• Wear ESD-safe clothes. Don't wear polyester clothing (such as a jogging suit) while you work on electronics. Polyester is an absolute haven for static buildup.
• Never introduce vinyl, Styrofoam, or plastic (except for your ESD-safe work tools) into your workspace environment.
• Wear ESD-safe, anti-static gloves. Natural oils from your fingers can transfer all too easily to the tiny IC components and conductive contacts inside electronics. When this happens, you can unintentionally create extra resistance and potential short-circuits.

Caution: ESD safe procedures will not protect you from high voltage discharges from a CRT display or a power supply capacitor.

Anti-static mats are made of a material that has high electrical resistance/low conductivity. When you connect the mat to a ground, it dissipates charge at a slow and controlled rate. When the mat's not connected to a ground, it insulates devices on it and prevents unintentional ESD to its surroundings.

Anti-static wrist straps create a conductive, high-resistance path from the user's arm to ground. The fabric band has conductive fibers woven into it, and there's a resistor (normally 1 MΩ) built into the path. When you connect the anti-static wrist strap to a ground, it dissipates charge through the wire at a slow and controlled rate. Anti-static wrist straps have no benefit if they're not grounded.

ESD-safe tools (such as our tweezers and spudgers) are either non-conductive or have a high-resistance coating. This prevents the tool from being a discharge conduit.

Blog: What is ESD? Silent Killer or Mythical Boogeyman?

Blog: ESD is Not a Venereal Disease

Video: ESD is Not a Venereal Disease

Video: Linus Tech Tips: Can static KILL your PC?

Video: Gamers Nexus: Static Electricity Misconceptions