— 7 —
3 ESD PRECAUSIONS
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be damaged easily
by static electricity.
Such components commonly are called Electrostatically Sensitive
Devices (ESD). Examples of typical ESD 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 for
potential shock reasons prior to applying power to the unit under
test.
(2) After removing an electrical assembly equipped with ESD
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
ESD devices.
(4) Use only an anti-static solder removal devices. Some solder
removal devices not classified as “anti-static” can generate
electrical charges sufficient to damage ESD devices.
(5) Do not use freon-propelled chemicals. These can generate
electrical charges sufficient to damage ESD devices.
(6) Do not remove a replacement ESD device from its protective
package until immediately before your are ready to install it.
(Most replacement ESD devices are packaged with leads
electrically shorted together by conductive foam, aluminum foil
or comparable conductive materials).
(7) Immediately before removing the protective materials from the
leads of a replacement ESD device, touch the protective material
to the chassis or circuit assembly into which the device will be
installed.
Be sure no power is applied to the chassis or circuit,
and observe all other safety precautions.
(8) Minimize bodily motions when handling unpackaged
replacement ESD devices. (Otherwise harmless motion such as
the brushing together of your clothes fabric or the lifting of
your foot from a carpeted floor can generate static electricity
sufficient to damage an ESD device).
www. xiaoyu163. com
QQ 376315150
9
9
2
8
9
4
2
9
8
TEL 13942296513
9
9
2
8
9
4
2
9
8
0
5
1
5
1
3
6
7
3
Q
Q
TEL 13942296513 QQ 376315150 892498299
TEL 13942296513 QQ 376315150 892498299