Haier TV-8888-09, Service Manual

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6
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by static electricity.
Such components are usually called Electrostatically Sensitive (ES) Devices.
Examples of typical ES devices are integrated circuits and some field effect
transistors and semiconductor “chip” components.
The following techniques should be used to help reduce the incidence of component
damage caused by static electricity.
1. Immediately before handling any semiconductor component or semiconductor-
equipped assembly, drain off any electrostatic charge on your body by touching a
known earth ground. Alternatively, obtain and wear a commercially available
discharging wrist strap device, which should be removed to prevent potential shock
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 aluminum 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 type folder removal device. Some solder removal devices
not classified as “anti-static” can generate electrical charges sufficient to damage ES
devices.
5. Do not use frond-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 you are
ready to install it. (Most replacement ES devices are packaged with leads electrically
shorted together by conductive foam, aluminum foil or comparable conductive
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: Ensure no power is applied to the chassis or circuit, and observe all other
safety precautions.
8. Minimize bodily motions when handling an unpackaged replacement ES device.
(Even some normally harmless motions such as mutual brushing of your clothes’
fabric or lifting of your foot from a carpeted floor might generate static electricity
sufficient to damage an ES device.)