Electrostatic discharge
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Introduction
Electrostatic discharge (ESD), caused by touching with the hand for example, can
destroy semiconductor components. The correct operation of the complete system is
then no longer assured.
Industry experience has shown that
all
semiconductor components can be damaged by
static electricity that builds up on work surfaces and personnel. The electrostatic
discharge can also affect the components indirectly via contacts or conductor tracks.
The electrostatic charges are produced by various charging effects of movement and
contact with other objects. Dry air allows greater static charges to accumulate. Higher
potentials are measured in areas with low relative humidity, but potentials high enough
to cause damage can occur anywhere.
The barred-hand symbol
Circuit packs containing components that are especially sensitive to electrostatic
discharge are identified by warning labels bearing the barred-hand symbol.
ESD instructions
Observe the following ESD instructions to avoid damage to electrostatic-sensitive
components:
•
Wear working garment made of 100% cotton to avoid electrostatic charging.
•
Touch the circuit packs at the edges or the insertion and removal facilities only.
•
Ensure that the rack is grounded.
•
Wear conductively connected wrist straps and connect them to the rack/subrack
ESP bonding point.
•
Work in an area which is protected against electrostatic discharge. Use conducting
floor and bench mats which are conductively connected to the rack/subrack ESP
bonding point.
•
Conductively connect all test equipment and trolleys to the rack/subrack ESP
bonding point.
Figure 1-2 ESD symbol
Safety
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1-20
Lucent Technologies - Proprietary
See notice on first page
365-374-187
Issue 1, December 2005