RED SYSTEM ESD Protection

ESD

Whenever there is movement, static charge is produced Static charge is caused by an excess or deficiency of electrons collected on a surface Electro Static Discharge is the rapid flow of charge between two objects Electro Static Charge and Discharge Fundamentals

A person walking on a carpet up to volts A person walking on a vinyl floor volts A person on a padded chair up to volts Styrofoam coffee cup up to 5000 volts Plastic or scotch tape up to 5000 volts Vinyl covered notebook ( Service Manual ) up to 8000 volts When Is a Static Charge Present?

¤TO FEEL IT volts or more ¤TO HEAR IT volts or more ¤TO SEE THE SPARK volts or more Electro Static Discharge

Voltage required to damage a component Device typeRange of ESD Susceptibility (volts) VMOS MOSFET EPROM100 JFET SAW OP AMP CMOS Diodes Bipolar Transistors Reference:Radiometer ESD book, code number

Electro Static Discharge 90 % that are damaged by ESD are zinged 10 % that are damaged by ESD are zapped. Zinged: - Components life span is reduced - Operating characteristic changed (intermittent failures and temperature sensitivity) Zapped: - Component totally destroyed

Static Dissipative Bench Mat Wrist Strap ESD Protected Area

Instrument for repair must be grounded Service person must have wrist strap connected Mains supplied test instruments must be grounded Solder iron must be grounded Discharge tools on bench mat before use Clean up Make ESD protected area visible Train the personnel Check facilities regularly General Requirements

Grounding example 1

Grounding example 2

Grounding example 3

Perform grounding (instrument, person, bench mat) Dismantle instrument Unpack replacement board and mount in instrument Place faulty/suspect board in ESD protected bag Remount instrument case Working Instructions

ESD sensitive devices will be delivered in protected bags or boxes ESD sensitive devices must be kept in protected bags or boxes outside protected area Unprotected ESD sensitive devices must be rejected Inventory/Transport

3M bench mat type 8214-R- part no M field kit type 8501-R- part no M wrist band type 2204-R- part no M cord for 2204, 1.5 m-R- part no M cord for 2204, 3 m -R- part no M bag 150 x 250 mm-R- part no M bag 200 x 300 mm-R- part no M bag 250 x 350 mm-R- part no M bag 350 x 450 mm-R- part no RADIOMETER ESD stock items

Manufacturing and stocking facilities in Copenhagen, January 15, 1993 Distributors service and stocking facilities, May 15, 1993 Implementation

Questionnaire ESD protection Have you implemented ESD protection in your company ? YesNo Have the person responsible for your stock received training in ESD ?YesNo Have you got ESD protected areas in your workshop ? YesNo Have you got portable ESD protection equipment ? YesNo Do you feel that you now have enough information to implement ESD protection in your company ?YesNo

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