The dsi
glossary provides a comprehensive list of Acronyms
and Abbreviations as well as definitions for several Terms
commonly used in the PCB industry.
Acronyms and Abbreviations
A-B
| AOI |
automated
optical inspection |
| µBGA |
micro ball
grid array |
| ASIC |
application-specific
integrated circuit |
| ATE |
automated
test equipment |
| ATG |
automatic
test generation |
| AXI |
automated
x-ray inspection |
| BBT |
bare
board test |
| BGA |
ball grid
array |
| BOM |
bill of
material |
C
| C |
capacitance |
| CAD |
computer
aided design |
| CAM |
computer
aided manufacturing |
| CED |
CAD Engineering
Division (dsi) |
| CIM |
Computer
Integrated Manufacturing |
| CPD |
Customer
Products Division (dsi) |
| CPK |
Critical
Part |
| CPP |
custom
prototype production |
| CPU |
central
processor unit |
| CS |
chip scale |
| CSL |
Contamination
Studies Lab |
| CSP |
chip-scale
packaging |
| CTE |
coefficient
of thermal expansion |
D
| DCA |
direct
chip attachment |
| DFA |
design
for assembly |
| DFM |
design
for manufacturability |
| DFT |
design
for testability |
| DI |
deonized
water |
| DRC |
design
rule check |
| DSI |
Diversified
Systems, Inc. |
E-F
| EMI |
electromagnetic
interference |
| ENG |
engineering |
| EPA |
Environmental
Protection Agency, a federal government regulatory group |
| Er |
dielectric
constant |
| ESD |
electrostatic
discharge |
| FDR |
frequency
domain reflectometry |
| FHP |
flying
head probe |
| FPD |
flat panel
display |
| FPD |
flat panel
display |
| FR4 |
epoxy-glass
laminate |
| FS |
Fourth
Shift (dsi's computer system) |
G-I
| HASL |
hot air
solder leveling |
| I/O |
input/output |
| IC |
ion chromatography,
integrated circuit |
| ICT |
in-circuit
test |
| IPC |
Institute
for Interconnecting and Packaging Electronic Circuits |
| IPC-PC-90 |
Industry
standard for statistical process control (SPC) |
| ISO |
International
Standards Organization |
J-L
| KGD |
known-good
die |
| LPI |
liquid
photoimageable |
| LPSM |
liquid
photoimageable soldermask |
| LSF |
low-solids
flux |
M-N
| MCM |
multi-chip
module |
| MECH |
mechanical |
| MFG |
manufacturing |
| MIS |
mounting
and interconnection structure |
| MLB |
multi-layer
board |
| MPU |
microprocessor
unit |
| MRC |
manufacturing
rules check |
O-P
| OA |
water soluble
(flux), organic acid |
| OEM |
original
equipment manufacturer |
| OSP |
organic
surface protectant |
| PCB |
printed
circuit board |
| PCD |
Printed
Circuit Division (PCB fabrication at dsi) |
| PGA |
pin grid
array |
| PSE |
Product
Support Engineer |
| PTH |
plated
through hole |
| PWB |
printed
wiring board |
Q-R
| QA |
quality
assurance |
| QC |
quality
control |
| QFP |
quad flat
pack |
| QS |
quality
systems |
| R |
resistance,
resistivity |
| RBB |
Rapid Bare
Boards (quick turn board fabrication at dsi) |
| RCR |
resin-coated
copper |
| RH |
relative
humidity |
| RIE |
reactive
ion etching |
| RMA |
rosin mildly
activated |
| ROI |
return
on investment |
| ROSE |
resistivity
of solvent extract |
| RPT |
Rapid Prototyping
Division (dsi) |
S
| SIR |
surface
insulation resistance |
| SMA |
surface
mount assembly |
| SMD |
surface
mount devices |
| SME |
Society
of Manufacturing Engineers |
| SMOBC |
solder
mask on bare copper |
| SMT |
surface
mount technology |
| SMTA |
Surface
Mount Technology Association |
| SPC |
statistical
process control |
| SVC |
split via
connection |
T-Z
| T/R |
transmit/receive |
| TC |
thermal
cycle |
| TDR |
time domain
reflectometry |
| THB |
temperature/humidity/bias |
| VI |
visual
inspection (human) |
| WOA |
weak organic
acid, water-soluble organic acid |
| WSF |
water soluble
flux |
Terms
A-B
| Annular
Ring |
The conductive
material surrounding a hole. |
| Aspect
Ratio |
The ratio
of the circuit board thickness to the diameter of the smallest drilled hole.
|
| Base Copper |
Copper
foil provided in sheet form or clad to one or both sides of the laminate
to be used as either internal or external layers of a circuit board. |
| Base Laminate |
The dielectric
material upon which the conductive pattern is formed. |
| Bed-of-Nails |
Test method
that uses an array of contact pins to test components. |
C
| Center-to-Center
Spacing |
The nominal
distance between the centers of adjacent features or traces on any layer
of a printed circuit board. Also known as "pitch". |
| Characteristic
Impedance |
A compound
measurement of the resistance, inductance, conductance, and capacitance
of a transmission line expressed in ohms. |
| Component
Hole |
A hole
used for the attachment and electrical connection of component terminations,
including pins and wires, to the printed circuit board. |
| Conductor |
A thin
conductive area on a PCB surface of internal layer usually composed of lands
and traces. |
| Contaminant |
An impurity
or foreign substance whose presence on printed circuit assemblies could
electrolytically, chemically, or galvanically corrode the system. |
| Continuity |
An uninterrupted
flow of electrical current in a circuit. |
| Cooldown |
The period
in the reflow process after peak temperature when the temperature drops
to the point where the solder joints solidify or freeze. |
D
| Defect |
Any deviation
from the normally accepted characteristics of a product or component. |
| Desmear |
Removal
of epoxy smear (melted resin) and drilling debris from a hole wall. |
| Dielectric |
An insulating
material that forms a nonconducting region between two or more conductors. |
| Dielectric
Constant |
The ratio
of permittivity of the material to that of a vacuum (referred to as relative
permittivity). |
| Drying
Time |
A portion
of the reflow process after preheat and before the reflow spike where volatile
materials escape from solder paste. |
E-H
| Etch |
Chemical
removal of metal (copper) to achieve a desired circuit pattern. |
| Flux |
A substance
used to promote or facilitate fusion such as a material used to remove oxides
from surfaces to be joined by soldering or welding. |
| Hole Density |
The quantity
of holes in a printed circuit board per unit area. |
| Hot Air
Solder Leveling |
The process
of dipping printed circuit boards into hot solder and leveling the surface
finish with hot air. Also known as HASL. |
I-K
| Innerlayer |
Any layer
which will be pressed on the inside of a multilayer board. |
| Insulation
Resistance |
The electrical
resistance of the insulating material (determined under specified conditions)
as measured between any pair of contacts or conductors. |
| Jumper
Wire |
An electrical
connection formed by wire between two points on a printed board added after
the intended conductive pattern is formed. |
L-N
| Laminate |
A product
made by bonding together two or more layers of material. |
| Laminate
Thickness |
Thickness
of the base material, not including metal-clad, prior to any processing.
Applies to single- or double-sided material. |
| Land |
A portion
of a conductive pattern usually, but not exclusively, used for the connection
and/or attachment of components. Also called Pad. |
| Mask |
A material
applied to enable selective etching, plating, or the application of solder
to a printed circuit board. |
| Microvia |
A via used
to make a connection between two adjacent layers, typically less than 6
mils in diameter. Microvias are typically formed by laser ablation, plasma
etching, or photo processing. |
| Mil |
One-thousandth
of an inch (0.001"). |
| Nail Heading |
The flared
condition of copper on the inner conductor layers of a multilayer board
caused by hole drilling. |
O-P
| Oxide |
A chemical
treatment to inner layers prior to lamination, for the purpose of increasing
the roughness of clad copper to improve laminate bond strength. |
| Pad |
The portion
of the conductive pattern on printed circuit boards designated for the mounting
or attachment of components. Also called Land. |
| Panel |
The square
or rectangular base material containing one or more circuit patterns that
passess successively through the production sequence and from which printed
cirucit boards are extracted. |
| Permittivity |
The measure
of the ability of a material to store electrical energy when exposed to
an electrical field. |
| Photomask |
A silver
halid or diazo image on a transparent substrate that is used to either block
or pass light. |
| Pinhole |
A minute
hole through a layer or pattern. |
| Pitch |
The nominal
distance between the centers of adjacent features or traces on any layer
of a printed circuit board. Also known as "center-to-center spacing". |
| Plated
Through Hole |
A hole
in a circuit board that has been palted with metal (usually copper) on its
sides to provide electrical connections between conductive pattern layers
of a printed circuit board. See PTH. |
| Plating |
Chemical
or electromechanical deposition of metal on a pattern. |
| Plating
Resists |
Material
over coductive areas used to prevent the plating of the covered areas. |
| Polymerize |
To unite
chemically two or more monomers or polymers to forma molecule with a higher
molecular weight. |
| Prepreg |
Sheet material
consisting of the base material impregnated with a synthetic resin, such
as epoxy or Polymide. |
| Printed
Circuit |
A conductive
pattern of printed components and circuits attached to a common base. |
| Printed
Wiring Board |
A part
manufactured from rigid base material upon which completely processed printed
wiring has been formed. |
Q-R
| Quench |
A cooling
process that is used to rapidly cool the molten solder below its melting
point in order to solidify it and obtain a strong and reliable solder joint. |
| Reflow |
A general
term referring to the overall process of reflowing solder paste in attaching
surface mount components to various substrates. It usually includes the
preheat process, stabilization and/or drying, the reflow spike, and cooldown,
but sometimes refers to the reflow spike area only. |
| Reflowing |
The melting
of an electro-deposit followed by solidifcation. |
| Registration |
The degree
of conformity of the position of a pattern, or a portion thereof, with its
intended position or with that of any other conductor layer of a board. |
| Relative
Permittivity |
See Dielectric
Constant. |
| Residue |
An undesirable
substance remaining on a substrate after a process step. |
| Resist |
Coating
material used to mask or to protect selected areas of a pattern from the
action of an etchant, solder, or plating. |
| Resistivity |
The ability
of a material to resist the passage of electrical current. |
| Rework |
Reprocessing
that makes articles conform to specifications. |
S
| Single-sided
Board |
A printed
circuit board with conductors on only one side and no plated-through holes. |
| Solder
Resists |
Coatings
which mask and insulate portions of a circuit pattern where solder is not
desired. |
| Solderability
Testing |
The evaluation
of a metal to determine its ability to be wetted by solder. |
| Soldermask |
A coating
applied to a circuit board to prevent solder from flowing onto undesirable
areas or from bridging across closely spaced conductors. |
| Stabilization
Period |
Period
of time after preheat and before the reflow spike where the internal termperature
differences between components are allowed to equalize. Also known as "drying
time", "preflow", and "soak". |
T-Z
| Test Coupon |
A sample
or test pattern typically made along the edge of the actual board pattern
that is used for testing to verify impedance or other parameters without
damaging the actual board. |
| Via |
A plated
through hole that is used as an innerlayer connection but doesn't have component
lead or other reinforcing material. |
| Wave Soldering |
A process
wherein assembled printed boards are brought in contact with a continuously
flowing and circulating mass of solder. |
Resources
EE International Glossary of Terms
IPC Glossary of Terms
Merix Interconnect Vocabulary
Surface Mount Equipment Manufacturers Association Reflow Terms and Definitions
4.0.
Top
of Glossary
Acronymns
and Abbreviations
Terms
