Specifications

RESARIO

OTEBOOK

AINTENANCE

AND

ERVICE

UIDE

1400 S

ERIES

EMOVAL

EQUENCE

Presario 1400 Series

Model XL240, XL241, XL242, XL244, XL245, XL246, XL247, XL250, XL340,

XL341, XL342, XL343, XL344, XL345, XL346, XL350, XL352, XL355, and XL356

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 that has been exposed to electrostatic discharge (ESD) may not seem to be affected and

work perfectly throughout a normal cycle. Although it may function normally for a period of time, it

may have been degraded 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 below shows activities that generate static electricity and their associated level of

electrostatic voltage.

Typical Electrostatic Voltages

Event Relative Humidity

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

Removing DIPS from vinyl trays 11,500 V 4,000 V 2,000 V

Removing DIPS from Styrofoam 14,500 V 5,000 V 3,500 V

Removing bubble pack from PCBs 26,000 V 20,000 V 7,000 V

Packing PCBs in foam-lined box 21,000 V 11,000 V 5,000 V

Note: 700 volts can degrade a product.