Electrostatic-sensitive device

Warning symbol denoting a device's susceptibility to electrostatic discharge.

Symbol for an ESD protection device – EPA

Symbol of an ESD grounding point for all components

An electrostatic-sensitive device (often abbreviated ESD) is any component (primarily electrical) which can be damaged by common static charges which build up on people, tools, and other non-conductors or semiconductors. ESD commonly also stands for electrostatic discharge.

As electronic parts like computer central processing units (CPUs) become packed more and more densely with transistors the transistors shrink and become more and more vulnerable to ESD.

Common electrostatic-sensitive devices include:

• MOSFET transistors, used to make integrated circuits (ICs)
• CMOS ICs (chips), integrated circuits built with MOSFETs. Examples are computer CPUs, graphics ICs.
• Computer cards
• TTL chips
• Laser diodes
• Blue light-emitting diodes (LEDs)
• High precision resistors

ESD-safe working

Often an ESD-safe foam or ESD-safe bag are required for transporting such components. When working with them, a technician will often use a grounding mat or other grounding tool to keep from damaging the equipment. A technician may also wear antistatic garments or an antistatic wrist strap

There are several kinds of ESD protective materials:

• Conductive: Materials with a resistance of between 1kΩ and 1MΩ
• Dissipative: Materials with a resistance of between 1MΩ and 1TΩ
• Shielding: Materials that attenuate current and electrical fields
• Low-charging or Anti-static: Materials that limit the buildup of charge by prevention of triboelectric effects through physical separation or by selecting materials that do not build up charge easily. Humans have natural electrical sources running through the body, touching an ESD unequipped can result in serious material damage.

See also

• Antistatic device
  • Antistatic garments
  • Antistatic agent

External links

• ESD Association
• Avoid Static Damage to Your PC, from PC World
• ESD advice from Intel
• Tips for Enhancing ESD Protection, for board designers