Samsung Xpress M288 Series Service Manual

1. Precautions1.3. ESD precautionsCertain semiconductor devices can be easily damaged by static electricity. Such components are commonly called“Electrostatically Sensitive (ES) Devices” or ESDs. Examples of typical ESDs are: integrated circuits, some field effecttransistors, and semiconductor “chip” components. The techniques outlined below should be followed to help reduce theincidence of component damage caused by static electricity.CAUTIONBe sure no power is applied to the chassis or circuit, and observe all other safety precautions.1) Immediately before handling a semiconductor component or semiconductor-equipped assembly, drain off anyelectrostatic charge on your body by touching a known earth ground. Alternatively, employ a commercially availablewrist strap device, which should be removed for your personal safety reasons prior to applying power to the unitunder test.2) After removing an electrical assembly equipped with ESDs, place the assembly on a conductive surface, such asaluminum or copper foil, or conductive foam, to prevent electrostatic charge buildup in the vicinity of the assembly.3) Use only a grounded tip soldering iron to solder or desolder ESDs.4) Use only an “anti-static” solder removal device. Some solder removal devices not classified as “anti-static” cangenerate electrical charges sufficient to damage ESDs.5) Do not use Freon-propelled chemicals. When sprayed, these can generate electrical charges sufficient to damage ESDs.6) Do not remove a replacement ESD from its protective packaging until immediately before installing it. Mostreplacement ESDs are packaged with all leads shorted together by conductive foam, aluminum foil, or a comparableconductive material.7) Immediately before removing the protective shorting material from the leads of a replacement ESD, touch the protectivematerial to the chassis or circuit assembly into which the device will be installed.8) Maintain continuous electrical contact between the ESD and the assembly into which it will be installed, untilcompletely plugged or soldered into the circuit.9) Minimize bodily motions when handling unpackaged replacement ESDs. Normal motions, such as the brushing togetherof clothing fabric and lifting one’s foot from a carpeted floor, can generate static electricity sufficient to damage an ESD.Copyright© 1995-2013 SAMSUNG. All rights reserved. 1-6