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a shock hazard, and the equipment should be repaired and rechecked
before it is returned to the customer.
2. PREVENTION OF ELECTRO STATIC DISCHARGE
(ESD) TO ELECTROSTATICALLY SENSITIVE (ES)
DEVICES
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such
components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES
devices are integrated circuits and some field-effect transistorsand semiconductor "chip" components.
The following techniques should be used to help reduce the incidence of component damage caused
by electro static discharge (ESD).
1. Immediately before handling any semiconductor component or
semiconductor-equipped assembly, drain off any ESD on your body by
touching a known earth ground. Alternatively, obtain and wear a
commercially available dischargingESD wrist strap, which should be
removed for potential shock reasons prior to applying power to the unit
under test.
2. After removing an electrical assembly equipped with ES devices, place
the assembly on a conductive surface such as alminum foil, to prevent
electrostatic charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES
devices.
4. Use only an anti-static solder removal device. Some solder removal
devices not classified as "anti-static (ESD protected)" can generate
electrical charge sufficient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate electrical
charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package
until immediately before you are ready to install it. (Most replacement
ES devices are packaged with leads electrically shorted together by
conductive foam, alminum foil or comparableconductive material).
7. Immediately before removing the protective material from the leads of a
replacement ES device, touch the protective material to the chassis or
circuit assembly into which the device will be installed.
Caution
Be sure no power is applied to the chassis or circuit, and observe all
other safety precautions.
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