Compaq CQ58 manual Grounding guidelines, Electrostatic discharge damage

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Grounding guidelines

Electrostatic discharge damage

Electronic components are sensitive to electrostatic discharge (ESD). Circuitry design and structure determine the degree of sensitivity. Networks built into many integrated circuits provide some protection, but in many cases, ESD contains enough power to alter device parameters or melt silicon junctions.

A discharge of static electricity from a finger or other conductor can destroy static-sensitive devices or microcircuitry. Even if the spark is neither felt nor heard, damage may have occurred.

An electronic device exposed to ESD may not be affected at all and can work perfectly throughout a normal cycle. Or the device may function normally for a while, then degrade in the internal layers, reducing its life expectancy.

CAUTION: To prevent damage to the computer when you are removing or installing internal components, observe these precautions:

Keep components in their electrostatic-safe containers until you are ready to install them.

Before touching an electronic component, discharge static electricity by using the guidelines described in this section.

Avoid touching pins, leads, and circuitry. Handle electronic components as little as possible.

If you remove a component, place it in an electrostatic-safe container.

The following table shows how humidity affects the electrostatic voltage levels generated by different activities.

CAUTION: A product can be degraded by as little as 700 V.

Typical electrostatic voltage levels

 

 

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 tube

2,000 V

700 V

400 V

 

 

 

 

Removing DIPS from vinyl tray

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 PCB

26,500 V

20,000 V

7,000 V

 

 

 

 

Packing PCBs in foam-lined box

21,000 V

11,000 V

5,000 V

 

 

 

 

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Chapter 4 Removal and replacement procedures

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Contents Compaq Presario CQ58 First Edition November Document Part Number Safety warning notice Iv Safety warning notice Table of contents Using Setup Utility Bios and System Diagnostics Power cord set requirements Viii Product description Hard drive WirelessCategory Description Memory Optical driveExternal media cards Power requirementsCategory Description PortsCategory Description Security Operating system PreinstalledServiceability Display External component identificationFinding your hardware and software information Component Description Communication and Chat CyberLink YouCamComponent Control Panel System and Security Power OptionsButton Keys Fn keyLights Component Description Speakers Produce sound TouchPadFront Left side Off power to the display and other Right side Bottom Illustrated parts catalog Service tag Description FunctionComputer major components Component Spare part numberPower button board includes cable Optical drive connector cable includes bracketRTC battery Power connector cable includes bracketBattery Wlan moduleComponent Spare part number Cover Kit, includes 686272-001 15.6-in, LED, SVA, HD, BrightView display panel Display assembly subcomponentsComponent Spare part number Display bezel Display Hinge Kit , includesDisplay enclosure Mass storage devices Hard Drive Hardware Kit , includesMiscellaneous parts Screw KitSequential part number listing Spare part number DescriptionReplacement thermal material Sequential part number listing Service considerations Removal and replacement proceduresPreliminary replacement requirements Tools requiredCables and connectors Grounding guidelines Electrostatic discharge damagePackaging and transporting guidelines Equipment guidelines Material Use Voltage protection levelComponent replacement procedures Service tagComputer feet Battery Description Spare part numberMemory module Wlan module Page Keyboard For use in country/region Spare part numberPage Page Page Optical drive Page Hard drive Page Page RTC battery Description Spare part number RTC battery 686274-001Top cover Page Page Power button board TouchPad button board 686271-001Page Page Optical drive connector cable Page Speakers Page USB board Page System board Page Page Fan/heat sink assembly Page Display assembly Page Page Page Page Page Page Page Page Power connector cable Page Updating the Bios Using Setup Utility Bios and System DiagnosticsStarting Setup Utility Bios Determining the Bios versionDownloading a Bios update Using System Diagnostics Specifications Computer specifications15.6-in, SVA, display panel display specifications Hard drive specifications Backing up, restoring, and recovering Creating recovery media and backupsCreating HP Recovery media See Creating HP Recovery media onRestore and recovery Using Windows Refresh for quick and easy recovery Help and SupportRemove everything and reinstall Windows Recovering using HP Recovery ManagerWhat you need to know Removing the HP Recovery partition Using HP Recovery media to recoverPower cord set requirements Requirements for all countriesRequirements for specific countries and regions Country/region Accredited agency Applicable note numberRecycling Index Hdmi TouchPad button