Electrostatic Discharge; Generating Static - Compaq Presario 1600 - Notebook PC Maintenance And Service Manual

MSG Index | Home Page
Illustrated Parts Catalog

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.
Event
Walking across carpet
Walking across vinyl floor
Motions of bench worker
Removing DIPS from plastic
tubes
Removing DIPS from vinyl
trays
Removing DIPS from
Styrofoam
Removing bubble pack from
PCBs
Packing PCBs in foam-lined box 21,000 V
NOTE: 700 volts can degrade
a product.
Return to Removal & Replacement Procedures
Maintenance & Service Guide
Presario 1660 Model
| Notice | Preface
| Removal & Replacement Procedures
Pin Assignments
Typical Electrostatic Voltages
Relative Humidity
10%
35,000 V
12,000 V
6,000 V
2,000 V
11,500 V
14,500 V
26,000 V
| Product Description
| Battery Pack Operations
40%
15,000 V
5,000 V
800 V
700 V
4,000 V
5,000 V
20,000 V
11,000 V
| Troubleshooting
| Specifications
55%
7,500 V
3,000 V
400 V
400 V
2,000 V
3,500 V
7,000 V
5,000 V