Compaq 1245 specifications Electrostatic Discharge, Generating Static

Maintenance & Service Guide

Presario 1200 Series

Model: 1245

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Electrostatic Discharge

A sudden discharge of static electricity from a finger or other conductor can destroy static-sensitive devices or microcircuitry.

●Often the spark is neither felt nor heard, but damage occurs. An electronic device exposed to an electrostatic discharge (ESD) may not be affected at all and will work perfectly throughout a normal cycle. Although it may function normally for a while, it is possible for the exposed device's internal layers to degrade, reducing its life expectancy considerably.

●Networks built into multiple integrated circuits provide some protection, but in many cases, the discharge can contain enough power to alter device parameters and melt silicon junctions.

Generating Static

This table shows the different electrostatic voltage levels generated

by various activities.

NOTE: 700 volts can degrade a product.

Typical Electrostatic Voltages

		Relative Humidity
Event	10%		40%	55%
Walking across carpet	35,000 V		15,000 V	7,500 V
Walking across vinyl floor	12,000 V		5,000 V	3,000 V
Motions of bench worker	6,000 V		800 V	400 V
Removing DIPS from	2,000 V		700 V	400 V
plastic tubes
Removing DIPS from vinyl	11,500 V		4,000 V	2,000 V
trays
Removing DIPS from	14,500 V		5,000 V	3,500 V
Styrofoam
Removing bubble pack	26,000 V		20,000 V	7,000 V
from PCBs
Packing PCBs in foam-lined	21,000 V		11,000 V	5,000 V
box

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