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ESD Information
ESD Information
What is ESD?
ESD stands for ElectroStatic Discharge.
Static electricity is an everyday phenomenon – there are few
of us who have not experienced a static shock on getting out
of a car or after walking across a room and touching the door
knob.
Other examples of static electricity are the cling of some fab-
rics to the body, the sticking of a plastic document cover, or
the attraction of dust to a TV or computer screen. It can
build up rapidly on objects, to produce surprisingly high volt-
ages.
Static electricity occurs when an object has an imbalance in
its electric charge. Objects with excessive electrons carry a
negative charge, whereas objects lacking electrons carry a pos-
itive charge. Charged objects need to be neutralized to rem-
edy this unstable energy state. If two objects that have
different voltages approach each other closely enough, charge
may pass from one object to the other in a fast electrostatic
discharge.
While this only lasts a microsecond or less, the peak discharge
current can be several Amps and the peak power can be in the
kiloWatt range! This discharge of electrons is called ESD.
ESD occurs when the resistance provided by the air gap is less
than that of other available paths to ground.
Why worry about ESD?
Basically because it can damage electronic components and
circuits.
We usually feel ESD, but ESD happens also at lower levels
that we cannot feel. Many ESD events are well below the
human sensitivity threshold of 3000 V but, unfortunately, an
increasing number of electronic components are susceptible
to damage from increasingly lower voltage levels. This trend
will continue as consumers demand more-compact products,
with increasing circuit density and decreasing component
size. Event levels as low as 20 V can damage some of the more
sensitive components.
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Gryphon™ ESD SH4248
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