APPENDICES
APPENDIX C
Handling Circuit Boards
Measures should be taken to ensure that technicians are properly grounded before
handling the Motherboard (SBC) or any other circuit boards. Certain components on
the Motherboard are sensitive to static electricity and can be damaged by discharge.
•
Handle all static sensitive components and circuit boards at a Static Safe Work Area
(ESD Workstation).
•
Always lay conductive carriers on the ESD Workstation’s mat and attach your wrist
strap before removing the components from the carrier.
•
Transport all static sensitive components in static shielding carriers or packages.
One particular hazardous time for static sensitive components is during handling and
shipping. Static charge on objects and personnel, even static buildup resulting from
movement of parts themselves, can blow or degrade parts.
•
Any board or device leaving the protection of the static safe work area must be
placed in the appropriate static shielding container. Once placed in such a container,
it is fully protected from both static discharge and external static field.
•
Only place components in, or remove them from, static shielding containers at a
static safe work place.
•
When using conductive foam, do not remove or insert ICs, unless at a static safe
work area. Make sure that leads do not penetrate to the other side of the foam.
•
It’s a good idea to put static awareness labels on all components leaving the work
area, to prevent removal from static shielding container during transit
•
Always handle circuit boards by holding their edges and avoid touching the
components on the board.
•
During PC board assembly, ensure that the ICs are the last of the components to be
mounted and that this is done at a protected workstation.
•
All tools used during assembly, including soldering tools and solder baths, must be
grounded. All hand-tools should be of conductive or anti-static material and, where
possible, should be insulated.
•
Avoid stacking boards with semiconductor devices; place them separately in static
dissipative board containers. Stacking can result in charging and discharging due to
friction.
•
When not being worked on, sensitive components and circuit boards must be
enclosed in shielded bags or containers. There are 3 types of ESD protective
enclosure materials: Static Shielding – prevents static electricity from passing
through the package.
Antistatic – provides antistatic cushioning for electronic assemblies.
Static Dissipative – an “over-package” that has enough conductivity to dissipate any
static buildup.
6-8 Preliminary Release
3/24/05