A Primer On Electro-Static Discharge; How Static Charges Are Created - Teledyne T300 Operation Manual

A PRIMER ON ELECTRO-STATIC DISCHARGE

14.

14.1. HOW STATIC CHARGES ARE CREATED

Materials
Makes
Contact
+
P = 3
ROTONS
E = 3
LECTRONS
N C = 0
ET HARGE
06864B DCN6314
Teledyne API considers the prevention of damage caused by the discharge of static
electricity to be extremely important part of making sure that your analyzer continues to
provide reliable service for a long time. This section describes how static electricity
occurs, why it is so dangerous to electronic components and assemblies as well as how
to prevent that damage from occurring.
Modern electronic devices such as the types used in the various electronic assemblies of
your analyzer, are very small, require very little power and operate very quickly.
Unfortunately, the same characteristics that allow them to do these things also make
them very susceptible to damage from the discharge of static electricity. Controlling
electrostatic discharge begins with understanding how electro-static charges occur in the
first place.
Static electricity is the result of something called triboelectric charging which happens
whenever the atoms of the surface layers of two materials rub against each other. As the
atoms of the two surfaces move together and separate, some electrons from one surface
are retained by the other.
+
P = 3
ROTONS
E = 3
LECTRONS
N C = 0
ET HARGE
Figure 14-1:
If one of the surfaces is a poor conductor or even a good conductor that is not grounded,
the resulting positive or negative charge cannot bleed off and becomes trapped in place,
+
P = 3
ROTONS
E = 2
LECTRONS
N C = -1
ET HARGE
Triboelectric Charging
Materials
Separate
+
P
ROTONS
E
LECTRONS
N C = +1
ET HARGE
= 3
= 4
325