SCOPE
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This guideline establishes the requirements for methods and materials used to protect electronic parts, devices,
and assemblies (items) that are susceptible to damage or degradation from electrostatic discharge (ESD). The
electrostatic charges referred to in this specification are generated and stored on surfaces of ordinary plastics,
most common textile garments, ungrounded person’s bodies, and many other commonly unnoticed static
generators. The passage of these charges through an electrostatic-sensitive part can result in catastrophic
failure or performance degradation of the part.
The part types for which these requirements are applicable include, but are not limited to the following:
All metal-oxide semiconductor (MOS) devices; e.g., CMOS, PMOS, etc.
Junction field-effect transistors (JFET)
Bipolar digital and linear circuits
Op-amps, monolithic microcircuits with MOS compensating networks, on-board MOS capacitors, or other
MOS elements
Hybrid microcircuits and assemblies containing any of the types of devices listed
Printed circuit boards and other types of assembly containing static-sensitive devices
Thin-film passive devices
definitions
Electrostatic discharge (ESD): A transfer of electrostatic charges between bodies at different electrostatic
potentials caused by direct contact or electrostatic field induction.
Conductive material: Material having a surface resistivity of 10
5
/square maximum.
Static dissipative material: Material having a surface resistivity between 10
5
and 10
9
/square.
Antistatic material: Material having a surface resistivity between 10
9
and 10
14
/square.
Surface resistivity: An inverse measure of the conductivity of a material and is the resistance of unit length
and unit width of a surface. Note: Surface resistivity of a material is numerically equal to the surface
resistance between two electrodes forming opposite sides of a square. The size of the square is immaterial.
Surface resistivity applies to both surface- and volume-conductive materials and has the dimension of
/square.
Volume resistivity: Also referred to as bulk resistivity, it is normally determined by measuring the resistance
(R) of a square of material (surface resistivity) and multiplying this value by the thickness (T).
Ionizer: A blower that generates positive and negative ions, either by electrostatic means or from a
radioactive energy source in an airstream and distributes a layer of low-velocity ionized air over a work area
to neutralize static charges.
Close proximity: For the purpose of this guideline, six inches or less.
device sensitivity per test circuit of Method 3015, MIL-STD-883C
Devices are categorized according to their susceptibility to damage resulting from electrostatic discharges
(ESD).
Category
ESD
Sensitivity
Class 1
0 V – 1999 V
Class 2
2000 V – 3999 V
Class 3
4000 V and above
At TI, devices are to be protected from ESD damage from receipt at incoming inspection through assembly,
test, and shipment of completed equipment.