Annular
Ring
The
remaining area of a pad after a hole is drilled through
the pad. It is a circular ring of conductive foil and
plating material.
AOI
Automated
optical inspection.
Aperture
A description
of the shape and size of the tool used to create a pad
or track. The term comes from the days of vector photo
plotters, where film was exposed by shining light through
apertures (shaped holes) arrayed around the edge of a
disk (or "aperture wheel"). Each aperture corresponded
to a different D code in the Gerber data. Today, photoplotters
use lasers to expose the film but the term "aperture"
persists.
Aperture
List / Aperture Table
A
list of the shapes and sizes for describing the pads and
tracks used to create a layer of a circuit board.
Aspect
Ratio
The
ratio of the circuit board thickness to the smallest hole
diameter.
Bare Board
A finished printed circuit board (PCB) that has
no components mounted yet.
Base Laminate
The substrate material upon which the conductive
pattern may be formed. The base material can be rigid
or flexible.
Blind via
A via hole that does not pass completely through
the printed circuit board. A blind via starts from one
side or another.
Buried via
A via connects two or more inner layers but no
outer layer, and cannot be seen from either side of the
board.
CEM1 or CEM3
PCB board materials, standard epoxy resin with
woven glass reinforcement over a paper core, differing
only in the type of paper used. They are less expensive
than FR4
Component Side
The side of a printed circuit board on which
most of the components will be mounted.
Double Side PCB
The pads & traces are on both sides of the
board.
Electroless Desposition/Plating
The deposition of conductive material from an
auto catalytic reduction of a metal ion on certain catalytic
surfaces.
Electroplating
The electrodeposition of a metal coating on a
conductive object. The object to be plated is placed in
an electrolyte and connected to one terminal of a d-c
voltage source. The metal to be deposited is similarly
immersed and connected to the other terminal. Ions of
the metal provide transfer to metal as they make up the
current flow between the electrodes.
Etching
Removing unwanted metallic substance by chemical
or chemical/electrolytic process.
FR-4
The most commonly used PCB board material. "FR"
stands for Flame Retardant and "4" means woven
glass reinforced epoxy resin.
Gerber
CAM Viewer
There are many Gerber viewers on the market. Here is a
short list: GC Prevue, ViewMate, GerbTool, CAM 350, CAMTASTIC,
CAMCAD, CAM Expert, Evgraver, ViewPlot.
HASL
Hot air solder levelling
Internal Layer
A conductive pattern which is contained entirely
within a multilayer printed board.
Multilayer PCB
The pads and traces are on both sides and
also there are traces embedded within the board. Speedy
PCB is able to provide 3-20 multi layer boards.
NPTH
NPTH: Non-plated Through Hole.
OSP
Organic Solder Preservative
Pad
The portion of the conductive pattern on printed
circuits designated for the mounting or attachment of
components.
Panel
An
array of, usually identical, separate circuits manufactured
on the same piece of material.
PCB
Design Software/Tools
Software that helps designer to do schematic, layout design,
routing and optimizations, etc. There are many desing
software and tools in the market. Some of them are free
PCB design software. Here is a short list: ExpressPCB,
EAGLE, PROTEL, CADSTAR, ORCAD, CIRCUIT MAKER, P-CAD 2000,
PCB ELEGANCE, EDWIN, VISUALPC, BPECS32, AUTOENGINEER,
EXPERT PCB, CIRCAD, LAYOUT, CIRCUIT LAYOUT, MCCAD, DREAM
CAD, E-CAD, POWERPCB, PCB ASSISTANT, PCB DESIGNER, QCAD,
QUICK ROUTE, TARGET 3001, WIN CIRCUIT 98, BOARD EDITOR,
PCB, VUTRAX, CIRCUIT CREATOR, PADSPCB, DESIGN WORKS, OSMOND
PPC, LAY01, SCORE, GElectronic, PRO-Board, PRO-Net , CSIEDA,
VISUALPCB, WINBOARD, ULTIBOARD, EASY PC, RANGER, PROTEUS,
EPD - Electronics Packaging Designer , AutoTrax Eda, SprintLayout,
CADINT, KICAD, Merlin PCB Designer, FREE-PCB, TinyCAD,
WINQCAD, Pulsonix, DIPTRACE.
PCB
Fabrication Process
A general process can be simplified as: Copper laminate
-> Drill board -> Deposit Cu -> Photolithography
-> Tin lead plate or finishing -> Etch -> Hot
air level -> Solder mask -> E-Testing -> Routing/V-scoring
-> Product inspection -> Final cleanning -> Packaging
.
PTH
Plated
Through Hole, a hole with the plated copper on its sides
to provide electrical connections between conductive patterns
at the levels of a printed circuit board. There are two
types of PTH. One is for mounting components and the other
is not used to mount component (see via).
RoHS
Restriction
of Hazardous Substances, is one of a handful of European
legislation intended to eliminate or severely curtail
the use of cadmium, hexavalent chromium, and lead in all
products from automobiles to consumer electronics.
RoHS
Compliant PCB
PCB
boards that are processed under RoHS regulations.
Silkscreen
Colored
marks (usually white) on the PCB board to identify components
for later assembly and trouble shooting processes. They
can be put on either or both sides of the board.
Single
Side PCB
The
pads and traces are on the one side of the board only.
Surface finish
We provide 5 default surface finishing processes
(HASL, OSP, Immersion gold, Immersion silver, Gold plating)
for all of regular boards.
Via
A plated through hole (PTH) in a Printed Circuit
Board that is used to provide electrical connection between
a trace on one layer of the Printed Circuit Board to a
trace on another layer. Since it is not used to mount
component leads, it is generally a small hole and pad
diameter. |
