5.12 Electrostatic sensitive devices

Question 1

Some electronic components or devices can be damaged by electrostatic discharge.

Answer 1

Electrostatic Sensitive Device (ESD) or Electrostatic Discharge Sensitive (ESDS).

Question 2

in general there are two classes of ESD what are they

Answer 2

Bipolar
Unipolar

Question 3

Bipolar devices use what to control current and operate in what ranges

Answer 3

current and milliampere

Question 4

Unipolar devices use what to control current and operate in what ranges

Answer 4

voltage and microampere

Question 5

Electronic parts that are classed as ESD are

Answer 5

Transistors (Metal Oxide Semiconductor Field Effect Transistor (MOSFET) transistors) used to make Integrated Circuits (IC)

Computer Central Processing Unit (CPU)

Graphic IC

Computer cards

Laser diodes

Blue Light-Emitting Diodes (LED)

High-precision resistors

Question 6

What Is Static Electricity?

Answer 6

Static electricity is an electric phenomenon whereby charged particles transfer from one body to another.

The imbalance of electric charges within, between, or on the surface of materials causes electrical discharge.

Question 7

what are the factors that contribute towards static electricity

Answer 7

Humidity
Temperature
Type of material
Form of movement

Question 8

Damage Caused to SSDs by Static Discharge

Answer 8

A local overheat
Evaporation
Bend
Layer-split or reduction
Holes
Short circuit – although this is very rare

Question 9

there are two main types of ESD failure what are they

Answer 9

hard failure ( catastrophic)
soft failure (latent)

Question 10

what precautions apply when working/handling ESD

Answer 10

ESD must only be handled by trained personnel.
ESD must be packaged, stored, and transported in appropriate containers. (Example below).
Operators, containers, tools, and test equipment must be properly grounded.
Containers must be identified appropriately (with the correct decals or placards).
All safety precautions and measures must be applied when handling and repairing ESD.
Faulty ESD must be handled with the same care as new ones, to avoid worsening the fault.

Question 11

(ESD) placards are used in a variety of situations to:

Answer 11

warn of the potential danger in areas where sensitive electronic devices are kept

alert personnel to the potential dangers of entering areas that contain sensitive electronic devices

provide information when removing sensitive electronic components from their sealed protection without taking the proper precautions beforehand.

Question 12

the electronic circuit boards with ESDS devices can be damaged by static electricity discharges. these defects cannot be seen externally.

Answer 12

Up to 80 - 90% of ESD damage does not result in a complete failure but degrades components and therefore reduces their lifetime.

Question 13

in relation to damage by static discharge.

Automatic test equipment(ATE) and built-in testing equipment(BITE) tests only what

Answer 13

failed, not degraded.

Question 14

passengers walking on a carpet can generate up to how many volts

Answer 14

15 000 V

Question 15

The amount of static electricity a person can generate depends upon many factors, including

Answer 15

clothing, cabin temperature, relative humidity, and carpet type

Question 16

The ESD problem can be reduced by considering the following when handling aircraft electronic components

Answer 16

Facilities
Personal protection
Verification of anti-static safeguards
Identification of ESDs or LRUs
Handling of ESD components

Question 17

All Electrostatic Sensitive Device (ESD) components must be transported in a closed conductive container

Answer 17

The container must be stored on a grounded rack and, when moved to the workstation, must have contact with the grounded table mat. When handling LRUs it is imperative to ensure that the rear connectors are protected with covers suitable for electrostatic handling.

Question 18

charged particles can transfer from one body to another.

Answer 18

.

Question 19

under what circumstances can the movement or separation of two materials generate more static electricity

Answer 19

if both materials are non conductive