Basics of Static Electricity
Photo courtesy of National Semiconductor
Electrical Energy
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How is Static Generated ?
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Contact and Separation
of Materials
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Demonstration:
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Attraction of Charge
Same charges,
repel
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Opposite
charges, attract
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Major Problems Caused by
Static Electricity
- Dust and lint attraction
- Handling problems
- Product damage
- Fire and explosion hazard
- Personnel shock
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Electric Field
Emanates from an electrical charge
and can affect electronics
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STATIC FIELD EMANATES FROM
CHARGED OBJECT
4,000V
2,000V
3,000V
5,000 Volts
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Conductor
A material that allows the flow of
electricity
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Grounded “Conductor”
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What is Ground?
Definition – “A place for electrons to go”
Types of Grounds:
Earth Ground
ESD Ground
Common Ground
Electrical System Ground
Water Pipe
Building Ground
Chassis Ground
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Electrical System Ground
(scr
ews
)
Ground
Attachment Points
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ews
r
c
(s
(Power Outlet)
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What if No Ground is
Available?
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Bonding
The attachment of two conductive
objects together to equalize their voltage
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Seated Personnel Must Wear
Wrist Strap
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Non-Conductor
A material that resists the flow of
electricity. Also called an “Insulator”
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Cannot Ground a Non-Conductor
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Ionization
The process of creating a positive
charge or a negative charge.
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Using an Ionizer
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Silicon Wafer
Photo courtesy of National Semiconductor
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“Chip” or Die
Photo courtesy of National Semiconductor
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Mounted Chip/Die (through-hole)
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Two Ways to Damage Electronics
An electric field
Static discharge
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STATIC FIELD
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Direct Discharge
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Types of ESD Failures to
Electronic Devices
Catastrophic Failure
◆ Device no longer operates
◆ Represents 10% of ESD failures
Intermittent / Walking Wounded
◆ Device is operational, but erratic and
will cause additional service calls
◆ Represents 90% of ESD failures
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DAMAGES CAUSED BY ESD
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Cost of Damage?
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Where Do I Need Static Protection?
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BASIC RULES OF STATIC
CONTROL
- Handle electronic components while
grounded or bonded.
- Transport electronic parts and assemblies in
proper containers or packages.
- Test your static protection products to make
certain that they are working properly.
- Make certain that others who enter your area
understand and practice these rules.
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Measurement of Worksurface
Electrical Properties
100 volts
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Electrical Resistance / Surface To Ground
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Testing Footwear
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Testing a Wrist Strap
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