"Compaq.com - Compaq Presario 1200 Series Maintenance and Service Guide - Models: 1230 and 1232

 

United States June 27, 2004

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Maintenance & Service Guide

Presario 1200 Series

Models: 1230 and 1232

Home Page Notice Preface Product Description Troubleshooting Illustrated Parts Catalog Removal & Replacement Procedures Specifications Pin Assignments Battery Pack Operations

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 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, then degrade in the internal layers, reducing its life expectancy.

Networks built into many integrated circuits provide some protection, but in many cases, the discharge contains enough power to alter device parameters or melt silicon junctions.

Generating Static

The table shows how different activities generate static electricity and at different electrostatic voltage levels.

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 plastic tubes

 

2,000 V

 

700 V

 

400 V

 

 

 

 

 

 

 

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