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Accelerated stress test A
test designed to stress the application until failure.
Acceptable Quality Level AQL. The maximum
allowable number of defects per 100 units.
Accuracy The ability to reach the target.
Acoustic Microscopy A test method using
ultrasonic sound to produce high resolution images.
Activator A chemical substance used to improve
the ability of a flux to clean component and PCB surfaces
for oxides and conta-
minants.
Active Component Component that actively
can change an electrical applied signal. Such as transistors
and IC's.
Adhesive A substance used to hold two materials
together. SMT adhesive is used to hold components
from placement until wave
soldered. Conductive adhesive is used
to form a mechanical and electrical connection as
an alternative to soldering.
Ag Chemical symbol for silver. Metal
with atomic No. 47. Used as protective layer on component
terminals, PCB solder pads and in
some solder alloys.
Air Knife Unit blowing air towards an object
in a thin straight line. E.g. used in wave soldering
machines to remove excess flux from
the PCB.
Algorithm A specification of actions solving
a task.
Alloy A material made by melting two or
more metals together.
Alumina White substrate material used primarily
in thick film applications.
Antimony Sb. Semi-metallic with atomic No.
51. Used in some solder alloys.
Antistatic Material Partly conductive material
resisting rapid static charging.
AOI Short for Automatic Optical
Inspection. Unit inspecting solder paste print
or soldered PCB's.
Aperture Opening in a metal stencil or
mesh screen.
Aperture file(s) Computer file(s) containing
X, Y coordinates, shape and aperture sizes used in
the stencil manufacturing process.
AQL Short for Acceptable Quality
Level. The maximum allowable number of defects
per 100 units.
Aqueous Water soluble.
Archimedes Pump Or auger pump. Dispensing
unit using an auger to force the adhesive onto the
PCB.
Aspect Ratio Stencil thickness to the
width of the smallest aperture or PCB thickness to
the diameter of the smallest hole.
Au Chemical symbol for gold. Metal with
atomic No. 79. Used as protective layer on PCB solder
pads, keyboards etc.
Auger Pump Or Archimedes pump. Dispensing
unit using an auger to force the adhesive onto the
PCB.
Automatic Optical Inspection AOI. Unit
inspecting solder paste print or soldered PCB's. |
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B |
Ball
Grid Array BGA. IC package with solder spheres
in an array on bottom side of component base substrate.
Ball Pitch Refers to the distance between
the centres of two balls on an BGA package.
Bare Board PCB that are not mounted with
components.
Bare Die An unpackaged IC (Die).
Bi Chemical symbol for bismuth. Metal
with atomic No. 83. Used in some solder alloys.
Bill of Materials BoM. List of components
for a PCBA. Containing reference no. and part no.
etc.
Bismuth Bi. Metal with atomic No. 83. Used
in some solder alloys.
BGA Short for Ball Grid Array.
IC package with solder spheres in an array on bottom
side of component base substrate.
Board Handling Unit Unit convey ring
PCBs from one machine to another or turning or flipping
the PCB.
BoM Short for Bill of Materials.
List of components for a PCBA. Containing reference
no. and part no. etc.
Bonding Materials joined together.
BQFP Short for Bumpered Quad
Flat Package. IC packages with leads
on four sides and corner bumpers.
Bulk Components Loose components . Components
delivered in special bulk containers can be supplied
to the placement
machine using a bulk feeder.
Bulk Feeder Unit used to feed components
from bulk containers into the placement machine.
Bumpered Quad Flat Package BQFP. IC packages
with leads on four sides and corner bumpers. |
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CAD
Short for Computer Aided Design.
Computer system used to design a product.
CAM Short for Computer Aided
Manufacturing. Computer system used to manufacture
a product.
CBGA Short for Ceramic Ball
Grid Array. As Ball Grid Array with
a ceramic base substrate.
Ceramic Ball Grid Array CBGA. As Ball Grid
Array with a ceramic base substrate.
Chemical Tin Or Immersion Tin. Used as protection
on PCB solder pads.
Chip Slang expression for a very small
component or an integrated circuit.
Chip On Board COB. An unpacked silicon
die placed directly on the PCB and wire bonded.
Chips Slang expression for very small
components like resistors and capacitors.
Chip Shooter Fast SMD placement machine
primarily placing small chips.
Chip-Scale Package CSP.
Very small package type. The IC chip is attached to
a carrier and connected to the balls on
the component
bottom side using via's and wire bonding.
CIM Short for Computer Integrated
Manufacturing.
COB Short for Chip On Board
COB. An unpacked silicon die placed directly
on the PCB and wire bonded.
Coefficient of Thermal Expansion CTE.
The ratio of change in dimension per unit change in
temperature.
Component Part. An element of a complete
functional unit.
Component Camera A camera in the SMD
placement machine used to recognize and measure the
position and angle of the
picked up components. The vision system
then calculate the necessary corrections for an accurate
placement on the PCB.
Computer Integrated Manufacturing CIM.
Computer Aided Design CAD. Computer system
used to design a product.
Computer Aided Manufacturing CAM. Computer
system used to manufacture a product.
Conductor Electrical connection. E.g. Printed
wiring on a PCB.
Conductor Thickness The thickness of a PCB
conductor track.
Conductor Width Width of a PCB conductor
track.
Controlled Convection Convection heat transferred
were temperature, flow, rate and velocity are accurately
controlled.
Convection Heat transfer occurring due to
temperature difference.
Cool Down Refers to the solder profile period,
after reaching the peak temperature, where the solder
alloy cools below the point
where the alloy solidify again.
Coplanarity The vertical variation of the
lead positions on a package.
Copper Cu. Metal with atomic No. 29. Used
mainly on PCB's as electrical connections forming
the circuit between the components.
CSP Chip-Scale Package. Very small package
type. The IC chip is attached to a carrier and connected
to the balls on the component
bottom side using via's and wire bonding.
CTE Short for Coefficient of Thermal
Expansion. The ratio of change in dimension
per unit change in temperature.
Cu Chemical symbol for Copper. Metal
with atomic No. 29. Used mainly on PCBs as electrical
connections forming the circuit
between the components.
Cycle Time The time it takes to perform
a complete cycle on the process in question.
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Discrete
Component Defined as separate components
in each package.
Delamination (PCB) A separation of the
different bonded layers within the PCB.
Delta T ΔT. Temperature differential.
Desoldering Removal of the solder alloy
from a joint.
Dewetting The molten solder repels on
the solder pad or component lead. Effect of poor solder-ability.
Double Layer PCB Double layer
printed circuit board. Laminate with two layers of
conductors forming a circuit pattern.
Double Layer Printed Circuit Board Double
layer PCB. Laminate with two layers of conductors
forming a circuit pattern.
Double Sided Reflow Soldering A
technique were SMC's are placed in solder paste and
reflow soldered firstly on one side of the
PCB and secondly repeated on the other
side. Gravity limits the type of packages that can
be used on the first mounted side.
Dross Oxidized solder alloy and contamination laying
on top of the molten solder in a wave soldering machine.
Dry-Pack Bags specially designed to MSD
storage.
Dry Run An expression for a SMD placement
machine running but without actually placing
components.
Dummy Component Non-functional component. |
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Edge
Conveyor Device transporting and supporting
the product (PCB) on the edge.
Electronics Manufacturing Services EMS.
Electrostatic Discharge ESD. The
transfer of an electrical charge between two objects
with different electrostatic potential.
Certain IC's are very sensitive
to ESD.
EMS Short for Electronics Manufacturing
Services.
ESD Short for ElectroStatic
Discharge. The transfer of an electrical
charge between two objects with different electrostatic
potential.
Certain IC's are very sensitive to ESD.
Etched Stencil Thin plate of steel or
brass with etched holes. Used in solder paste printing.
Etching A chemical process that removes
selected material that are not covered by a protective
resist.
Eutectic Solder Alloy An alloy that change
directly from solid to liquid state at a exact temperature.
The eutectic alloy also have a
lower melting point than of its different
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FC
Short for Flip-Chip. Refers to
bare silicon IC's flipped and attached directly onto
the PCB.
Fiducial Camera Camera used to measure the
PCB position relative to the placement head.
Fiducial Mark A small mark on the PCB
used to calculate the PCB position relative to the
placement head. The calculations are then
used to ensure precise placement of the
components.
Fillet A solder fillet is the build up of
solder between the solder land and the component terminal.
Fine Pitch Refers to a short distance between
the centres of two leads on an IC. 0.5 mm (20 mil)
and down.
Fine Pitch Ball Grid Array FPBGA. See
Ball Grid Array.
Fine Pitch Placer A very accurate SMD placement machine capable of
placing fine pitch components.
Fine Pitch Quad Flat Package FPQFP or
FQFP. Refers to a specific group of fine pitch IC
packages with leads on all four sides.
Fine Pitch Technology FPT. Technology
involving components with very short distance between
the centres of two leads.
From 0.5 mm (20 mil) and down.
First Pass Yield Yield. Finished units (in
percent) not requiring rework.
Flex PCB Flexible (bendable) printed circuit
board. Base materials are Polyamide (Kapton) or Polyester
(PET), adhesive and
conductive foil.
Flip-Chip FC. Refers to bare silicon
IC's flipped and attached directly to the PCB.
Flood Bar Used in some screen printers
to drag the printing material back after a squeegee
stroke. Not commonly used anymore.
Flux Chemical mixture usually containing
Rosin or synthetic resin (40-50%), activators
(20-35%), rheological additives and finally
solvents. When heated used to
clean component and PCB surfaces for oxides
and contaminants.
Flux Activation Temperature The temperature
at which the flux starts cleaning component and PCB
surfaces for oxides and
contaminants.
Fluxer Unit used in a wave soldering
machine to apply flux to the bottom side of the PCB.
Foam Fluxer Fluxer unit creating a foam
wave of flux by pumping the flux through a porous
material. Used in a wave soldering
machine to apply flux to the bottom side
of the PCB.
Forced Convection Heat transfer occurring
when forcing a gas over a solid media.
Forced Convection Furnace Oven. Soldering
machine using a high flow of hot air / N2
to transfer heat and solder SMD mounted
PCB's .
Forced Convection Oven Furnace. Soldering
machine using a high flow of hot air / N2
to transfer heat and solder SMD mounted
PCB's.
Foot Length The length of the component
lead foot. The part of the lead approximately parallel
with the solder pad.
Foot Width Width of the component lead.
Footprint Land Pattern.
Refers to the area, pad dimensions and the pattern
of pads for a particular component.
Footprint Refers to the floor area a
machine takes up.
FPBGA Short for Fine Pitch
Ball Grid Array. See Ball Grid
Array.
FPQFP Short for Fine Pitch
Quad Flat Package. Refers to
a specific group of fine pitch IC packages with leads
on all four sides.
FPT Short for Fine Pitch
Technology. Technology involving components
with very short distance between the centres of two
leads.
From 0.5 mm (20 mil) and down.
FQFP Short for Fine pitch Quad
Flat Package. Refers to a specific group
of fine pitch IC packages with leads on all four sides.
FR2 Phenol PCB base laminate. Widely
used in consumer products.
FR4
Glass epoxy laminate. The most commonly
used PCB base material. |
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GEM
Short for General Equipment Module.
A communication protocol for communication between
production equipment.
General Equipment Module GEM. A communication
protocol for communication between production equipment.
Glass Transition Temperature Tg. The
temperature at which a material changes from hard
to soft state.
Global Fiducial Marks Two or three small
marks on the PCB are used to calculate the PCB position
relative to the placement head.
The calculations are then used to ensure
precise placement of all the components.
Gold Au. Metal with atomic No. 79. Used
as protective layer on PCB solder pads, keyboards
etc.
Golden Board Known Good Board. Used as reference
in electrical testing.
Gull Wing An "Old" frase for QFP IC's. The leads
flare outward from the component body.
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HAL
Short for Hot Air Levelling.
Also called HASL. A
hot air knife levels the SnPb solder pad finish.
Halide A chemical compound used as activator
in flux.
HASL Short for Hot Air
Solder Levelling. Also called HAL. A
hot air knife levels the SnPb solder pad finish.
Hot Air Levelling HAL. Also called HASL.
A
hot air knife levels the SnPb solder pad finish.
Hot Air Solder Levelling HASL. Also called
HAL. A
hot air knife levels the SnPb solder pad finish. |
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IC
Short for Integrated Circuit.
Package containing multiple components forming
a specific circuit.
Integrated Circuit IC. Package containing multiple
components forming a specific circuit.
Immersion Tin Chemical applied tin. Used
as protection on PCB solder pads.
In Chemical symbol for Indium. Metal
with atomic No. 49. Used in some solder alloys.
Indium In. Metal with atomic No. 49.
Used in some solder alloys.
Inert Gas Inactive gas such as nitrogen.
Nitrogen is used in the soldering process to avoid
oxidation of the components, pads and
solder alloy.
Infrared IR. Refers to energy (heat)
transfer by Infrared wave length radiation. Used in
some soldering systems.
Inner Layer A conduvtive internal layer of
a PCB laminate.
Intelligent Feeder A feeder equipped
with a microprocessor system designed to avoid set-up
and inventory errors.
Intermetalic Layer A relatively thin
layer of metal compound formed between two different
metals. E.g. between the copper pads
and solder alloy used.
IR Short for Infrared. Refers
to energy (heat) transfer by Infrared wave length
radiation. Used in some soldering systems. |
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J
lead Refers to a component with J shaped
leads like PLCC and SOJ packages.
Joint Solder joint. Mechanical and electrical
connection between component terminal and PCB solder
pad. |
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Known
Good Board Golden board. Used as reference
in electrical testing. |
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Land
Pad or solder pad. A PCB termination area.
Land Pattern Footprint. Refers to the
area, pad dimensions and the pattern of pads for a
particular component.
Large Component Mounter A SMD placement machine capable of handling large
components.
Laser Cut Stencil Thin plate of steel,
brass or plastic with laser cut holes. Used in solder
paste printing.
Lead Pb. Metal with atomic No. 82. At
the time used in most solder alloys.
Lead Component
terminal or electrical connection point.
Lead-Free Refers
to solder alloy and solder joints not containing lead.
Lead-Free Solder Refers to solder alloy
that are not containing lead.
Lead-Free Soldering Refers to a soldering
process where lead-free solder alloy are used.
Leadless Component An "old" phrase for
surface mount component.
Lead Pitch Refers to the distance between
the centres of two leads on an IC.
Liquidus Temperature The temperature
above which an alloy become totally liquid.
Local Fiducial Marks Two or three small
marks on the PCB are used to calculate the PCB position
relative to the placement head.
The calculations are then used to ensure
precise placement of a particular component.
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Manual
Assembly Assembly process done manually
by an operator.
Matrix Tray Tray. Flat plastic matrix
component carrier.
Melf Metal ELectrode Face.
Refers to a specific group of cylindrical components.
Melting Point The specific temperature
at which an alloy become liquid.
Mesh Screen A woven stainless steal or
polyester fibre mesh attached with emulsion, used
in the screen printing process.
Mesh Size The number of openings per
inch in a mesh screen.
Metal Content The weight percent of the
solder powder in a solder paste.
Metal Electrode Face Melf. Refers to
a specific group of cylindrical components.
MicroBga μBGA. Refers to a group of fine
pitch BGA's.
Moisture Sensitive Device MSD. Components
that optain moist and has a high potential of cracking during
soldering due to
moist expansion.
MSD Short for Moisture Sensitive
Device. Components that optain moist and has
a high potential of cracking during soldering
due to moist expansion.
Mulitilayer PCB Multilayer Printed
Circuit Board. Laminate with more than 2 layers of
conductors forming a circuit pattern.
Mulitilayer Printed Circuit Board Multilayer
PCB. Laminate with more than 2 layers of conductors
forming a circuit pattern. |
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Ni Chemical symbol
for nickel. Metal with atomic No. 28. Used under Au
on PCB solder lands and on component terminals.
Nickel Ni. Metal with
atomic No. 28. Used under Au on PCB solder lands and
on component terminals.
N2 Nitrogen. Inert
gas used in the soldering process to avoid oxidation
of the components, pads and solder alloy.
Nitrogen N2. Inert gas used in
the soldering process to avoid oxidation of the components,
pads and solder alloy.
No-Clean Term used about flux, solder
paste and solder wire that contain flux, formulated
in such a way that it is not necessary to
remove the remaining flux on the PCB.
Acids should be encapsulated in the flux residue and
the residue should work as an electrical
insulator.
Nozzle A
vacuum nozzle holding the component during transport
from feeder unit to PCB. An adhesive nozzle used to
transfer
adhesive to the PCB.
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OA
Short for Organic Acid flux. Classification
for a water soluble flux usually containing organic
acids and no rosin.
OEM Short for Original
Equipment Manufacturer.
OMPAC Short for Over Molded
Plastic Array Carrier. Motorola
brand name for PBGA.
Organic Acid flux OA. Classification
for a water soluble flux usually containing organic
acids and no rosin.
Organic Solder ability Preservative OSP.
Used as protective layer over cobber solder pads.
Original Equipment Manufacturer OEM.
OSP Short for Organic Solder ability Preservative. Used as
protective layer over cobber solder pads.
Over Molded Plastic Array Carrier OMPAC.
Motorola trade name for PBGA.
Oxidation Oxygen absorption on metal
surfaces. The oxides resist solder wetting. |
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Pad Land or solder
pad. A PCB termination area.
Panel Cluster panel.
A PCB panel usually containing an array of identical
PCB's. After end assembly the PCB's are separated.
Part Component. An element
of a complete functional unit.
Parts Per Million PPM. Unit commonly used in statistics.
Paste In Hole A SMT technique used to solder
through hole / leaded components. Solder paste is
printed onto the through-hole
solder pad, part inserted and reflow soldered.
Pattern Repeat A placement method where
each PCB in a panel is completely populated before
moving on to the next.
Pb Chemical symbol for lead. Metal with
atomic No. 82. At the time used in most solder alloys.
PBGA Short for Plastic Ball
Grid Array. As Ball Grid Array with
a thin BT resin epoxy PCB base substrate.
PCA Short for Printed Circuit
Assembly. Completed PCB unit.
PCB Short for Printed Circuit Board. Substrate with
conductors forming a circuit pattern.
PCBA Short for Printed Circuit
Board Assembly. Completed PCB unit.
PCB Support Pins or plates supporting
the PCB during a process.
Peak Temperature The maximum temperature
reached in the soldering process.
pH A liquid acidity and alkalinity measurement
unit. Scale 1 - 14, 1 acid, 7 neural and 14 alkaline.
Pick and Place P&P. Refers to the
process where the components are picked up from a
feeding unit, moved and placed onto
the PCB solder pads.
Pick and Place Head P&P Head. Refers
to the head in a placement machine, picking up the
components from a feeding unit,
moving and placing them on the PCB solder
pads.
Pin In Paste A SMT technique used to
solder through hole / leaded components. Solder paste
is printed onto the through-hole
solder pad, part inserted and reflow soldered.
Piston Pump Dispensing unit using a piston
to force the adhesive onto the PCB.
Pitch The distance between the centres
of two leads on an IC. Or the distance between the
components in a tape carrier. Or the
distance between two tape adjacent sprocket
holes (4 mm).
Placement A manual, semi-automatic or
fully automatic component assembly process.
Placement Head P&P Head. Refers to
the head in a placement machine, picking up the components
from a feeding unit and
moving and placing them on the PCB solder
pads.
Placement Program Computer data containing
placement sequence and other necessary information
that the placement machine
require.
Plastic Ball Grid Array PBGA. As Ball
Grid Array with a thin BT resin epoxy PCB base substrate.
Plastic Leaded Chip Carrier PLCC. Refers
to a specific group of IC packages with J-lead on
four sides.
PLCC Short for Plastic Leaded
Chip Carrier. Refers to a specific group
of IC packages with J-lead on four sides.
Popcorning Internal delamination
of a BGA due to moist expansion inside the BGA housing.
PPM Short for Parts Per
Million. Unit commonly used in statistics.
Preform Solder preform. A preformed shape
of solder alloy. Usually flux containing.
Preheat Refers to the part of the soldering
profile where the PCB is heated from ambient temperature
until reaching the chosen
preheat temperature.
Printed Circuit Board PCB.
Laminate with conductors forming a circuit pattern.
Printed Circuit Board Assembly PCBA or
PCA. Completed PCB unit.
Process Control A manual or automatic
procedure set up to monitor the process in question.
Profiler A unit recording the soldering
profile during the soldering process at a number of
locations.
P&P Short for Pick and Place. Refers
to the process where the components are picked up
from a feeding unit and moved to and
placed on the PCB solder pads.
P&P Head Short for Pick and
Place Head. Refers to the head in a placement
machine, picking up the components from a feeding
unit and moving and placing them on the
PCB solder pads. |
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QFP Short for Quad
Flat Package. Refers to a specific group
of IC packages with leads on all four sides.
Quad Flat Package QFP. Refers to a specific
group of IC packages with leads on all four sides. |
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R
Short for Rosin flux. Flux usually containing
40% solids (Rosin) and 60% solvents.
RA Short for Rosin Activated
flux. Classification for an aggressive flux, containing
1 - 5 % activators.
Reflow Furnace Reflow oven. Equipment used
to solder SMD mounted PCB's.
Reflow Oven Reflow furnace. Equipment
used to solder SMD mounted PCB's.
Reflow Period Refers to the part of the soldering profile, after
the equalization periode, used to melt the solder
paste and form the
solder joints.
Reflow Process Refers to the process, where the mounted PCB
is heated in a furnace by a hot atmosphere or IR radiation
in specific
stages, finally melting the solder
paste and thereby forming the solder joints.
Reflow Soldering The mounted PCB is heated in a furnace
by a hot atmosphere or IR radiation in specific stages,
finally melting the
solder paste and thereby forming the solder
joints.
Reflow Temperature The temperature at
which the reflow soldering are performed. Usually
described as a window. E.g. 215 -
230°C.
Reliability The products, PCB's, solder
joints ability to fulfil the specifications required.
Repair Rework or Touch-Up. Refers to
a process where a defective unit or part is changed
into a working condition.
Repeatability The ability to deliver
consistent results.
Resin Chemically synthesized rosin.
Rework Repair or Touch-Up. Refers to
a process where a defective unit or part is changed
into a working condition.
Rheology Material viscous and flow property.
Rosin Natural rosin extracted from pine
trees.
Rosin flux R.
Flux usually containing 40% solids (Rosin) and 60%
solvents.
RMA Short for Rosin Mildly
Activated flux. Classification for an moderate
flux containing less than 1% activators.
Rosin Activated RA. Classification
for an aggressive flux, containing 1 - 5 % activators.
Rosin Mildly Activated RMA. Classification
for a moderate flux containing less than 1% activators.
RMS Short for Root Mean
Square.
Root Mean Square RMS. |
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Sb
Chemical symbol for antimony. Semi-metallic
with atomic No. 51. Used in some solder alloys.
Scooping When a squeegee blade bend and
scoop the solder paste out of a wide aperture.
Screen Mesh A woven stainless steal or polyester
fibre mesh attached with emulsion, used in the screen
printing process.
Screen Printing Solder paste or advesive
printed through a mesh screen.
Self-Alignment Swimming. When a component
moves on the solder pads due to the surface tension
of the molten solder alloy.
Selica Gel Moisture absorbing crystals.
Used in Dry-Packs to maintain a low moist level.
Short Solder bridge. An unintentional mechanical
and electrical short between two component terminalsor
solder pads.
Shrink Small Outline Package SSOP. Refers
to a specific group of small IC packages.
Single Layer PCB Single layer
printed circuit board. Laminate with one conductive
layer forming a circuit pattern.
Single Layer Printed Circuit Board Single
layer PCB. Laminate with one conductive layer forming
a circuit pattern.
Silver Ag. Metal with atomic No. 47. Used
as protective layer on component terminals, PCB solder
pads and in some solder alloys.
Skew Component misalignment from its target
position.
Slump Solder paste spreading after printing.
Small Outline SO. Refers to a specific
group of IC packages with leads on two sides.
Small Outline Diode SOD. Refers to a
specific group of diode packages.
Small Outline Integrated Circuit SOIC.
See SO.
Small Outline J-lead package SOJ. Refers
to a specific group of IC packages with J-lead on
two sides.
Small Outline Package SOP. Refers to
a specific group of IC packages.
Small Outline Transistor SOT. Refers
to a specific group of transistor and diode packages.
SMC Short for Surface Mount
Component. Component designed for PCB surface
mounting.
SMD Short for Surface Mounted
Device. PCB mounted with SMC's.
SMD Short for Solder Mask
Defined. Pad that are defined by the solder
mask.
SMEMA Short for Surface Mount
Equipment Manufacturers Association.
Provides standards for mechanical equipment interface,
fiducial marks etc.
SMT Short for Surface Mount
Technology. A technology where components are
attached directly onto the PCB surface.
Sn Chemical symbol for tin. Metal with
atomic no. 50. Main ingredient in solder alloys.
Snap Off The distance between the stencil
and the PCB in the printing situation.
SO Short for Small Outline.
Refers to a specific group of IC packages with leads
on two sides.
Soak Period Stabilization Period. Refers
to the part of the soldering profile, after preheat,
used to equalize the components
temperature differences before raising
the PCB temperature above the solder alloys melting
point.
SOD Short for Small Outline
Diode. Refers to a specific group of diode
packages.
SOIC Short for Small Outline
Integrated Circuit. See SO.
SOJ Short for Small Outline
J-lead package. Refers to a specific group
of IC packages with J-lead on two sides.
Solder-ability The ability of the solder
to wet a solder land.
Solder Alloy A material made by melting
two or more metals together.
Solder Bead A solder ball positioned
at the side of the component. Usually seen at chips.
Solder Bridge Short. An unintentional
mechanical and electrical short between two component
terminals and solder pads.
Solder Joint Joint. Mechanical and electrical
connection between component terminal and PCB solder
pad.
Solder Mask Solder protection coating
masking selected areas of the PCB surface.
Solder Mask Defined SMD. Pad that are
defined by the solder mask.
Solder Pad Land or solder pad. A PCB
termination area.
Solder Paste A homogeneous paste of solder
particles, flux, solvents and additives. Used in the
SMT reflow soldering process.
Solder Preform Preform. A preformed shape
of solder alloy. Usually flux containing.
Solder Wire A wire of solder alloy containing
flux. Used for hand soldering.
Solder Thief A special designed solder
land positioned outside the real SMC solder pads used
to attract excess solder and thereby
avoid solder bridges. Used in wave soldering
process.
Solidus Temperature The temperature just
below the point where the alloy become liquidus.
Solvent A liquid cleaning agent and ingredient
in some fluxes and solder pastes.
SOP Short for Small Outline
Package. Refers to a specific group of IC packages.
SOT Short for Small Outline
Transistor. Refers to a specific group of transistor
and diode packages.
SPC Short for Statistical Process
Control. A method used to continuously monitor
a process and thereby be able to reduce product
failure.
Spray Fluxer Fluxer unit used in a wave
soldering machine to apply flux to the bottom side
of the PCB by spraying it through a
nozzle or an ultrasonic transducer.
Squeegee A metal or rubber blade used
in solder paste / adhesive printing. By an angled
movement across the stencil or screen
the squeegee force the solder paste or
adhesive through the stencil apertures and onto the
PCB surface.
SSOP Short for Shrink Small
Outline Package. Refers to a specific
group of small IC packages.
Stabilization Period Soak period. Refers
to the part of the soldering profile, after preheat,
used to equalize the components
temperature differences before raising
the PCB temperature above the solder alloys melting
point.
Statistical Process Control SPC. A method
used to continuously monitor a process and thereby
be able to reduce product failure.
Stencil Thin plate of steel, brass or
plastic with etched or laser cut holes. Used in solder
paste printing.
Stencil Printing Solder paste printing
through a metal stencil.
Step & Repeat A placement method
where one particular component is placed on each PCB
in a panel before placing the next
component.
Stick Plastic tube component carrier.
Stick Feeder Unit used to feed components
from plastic tube carrier into the placement machine.
Substrate An insulating
material on which the components are placed, soldered
and forming a circuit.
Surface Mount Component SMC. Component
designed for PCB surface mounting.
Surface Mounted Device SMD. PCB mounted
with SMC's.
Surface Mount Equipment Manufacturers Association
SMEMA. Provides standards for mechanical equipment
interface,
fiducial marks etc.
Surface Mount Technology SMT. A technology
where components are attached directly onto the PCB
surface.
Surface Tension The attraction force
on the surface of a liquid.
Swimming Self-Alignment. When a component
moves on the solder pads due to the surface tension
of the molten solder alloy. |
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T |
TAB
Tape Automated Bonding. A process where a taped
IC chip is bonded directly onto a PCB.
Tact Time The time a placement head use
to pickup and place one component.
Tape Paper or plastic embossed / blister
component carrier.
Tape Carrier The paper or plastic embossed
/ blister carrier tape in which the components are
stored in pockets.
Tape Cover A clear plastic film covering
the components stored in the tape carrier.
Tape Automated Bonding TAB. A process where
a taped IC chip is bonded directly onto a PCB.
Tape feeder Unit used to feed components
from tape into the placement machine.
Tape Pitch The distance between the components
in a tape carrier. Jumps in 4 mm interval.
Tape width The width of the tape carrier.
8, 12,16, 24, 32, 44, 56 and 72 mm.
Temperature Profile A profile showing the
temperature over a period of time. In soldering the
profile usually consist of 4 phases;
preheat, stabilization, reflow and cooling.
Terminal Component lead or electrical connection
point.
Tg Glass transition temperature. The
temperature at which a material changes from hard
to soft state.
Tin Sn. Metal with atomic no. 50. Main
ingredient in most solder alloys.
Theta Amount of rotation.
Thin Quad Flat Package TQFP. Refers to
a group of thin IC packages with leads on all four
sides.
Thin Shrink Quad Flat Package TSQFP.
Group of small and thin IC packages with leads on
four sides.
Thin Shrink Small Outline Package TSSOP.
Refers to a specific group of small and thin IC packages.
Thin Small-Outline Package TSOP. Refers
to a package type usually used for memory ICs.
Thixotropic A solder paste or adhesives
characteristic of becoming more fluid when in motion.
Time Above Liquidus Refers to the period
of time at which the solder alloy is liquidus.
Tomb Stoning A component flipped to a
vertical position on one solder pad.
Tooling Hole Non plated holes used for
PCB alignment during processing.
Touch Less Centring Component centring
using vision or laser alignment.
Touch-Up Repair or Rework. Refers to
a process were a defective unit or part is changed
into a working condition.
TQFP Short for Thin Quad
Flat Package. Refers to a group of thin
IC packages with leads on all four sides.
Tray Waffle tray. Flat plastic
matrix component carrier.
Tray Elevator Tray Handler. Tray component
feeding unit supplying the component into the placement
machine.
Tray Handler Tray Elevator. Tray component
feeding unit supplying the component into the placement
machine.
TSOP Short for Thin Small-Outline
Package. Refers to a package type usually used
for memory ICs.
TSQFP Short for Thin Shrink
Quad Flat Package. Group of small
and thin IC packages with leads on four sides.
TSSOP Short for Thin Shrink
Small Outline Package. Refers
to a specific group of small and thin IC packages.
Turret Head A placement head unit with
multible heads, rotating parallel to the PCB.
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U |
Underfilling A filling material
is injected under the component. Usually used on Flip-Chip
applications to improve reliability.
Ultraviolet UV. Refers to energy transfer
by ultraviolet wavelength radiation. Used in some
curing systems.
UV Short for Ultraviolet.
Refers to energy transfer by ultraviolet wavelength
radiation. Used in some curing systems. |
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V |
Vapor
Phase Soldering Refers to condensation heating
where the PCB is lowered into a hot vapor. The vapor
condensate at the
PCB surface and thereby heating it.
Via Hole A plated through-hole connecting
the PCB conductive layers.
Vibrating Feeder A vibrating unit used to
feed components from plastic tube carrier in to the
placement machine.
Viscosity A materials resistance to flow.
Measured in centipoise or millipascal.
Vision Centring A touch less component
centring using vision process alignment.
VOC Volatile Organic Compound. A organic
fluid that rapidly vaporizes.
Void A enclosed space inside
a solder fillet. Primarily caused by solder encapsulated
out-gassing of solvents.
Volatile Organic Compound VOC. A organic
fluid that rapidly vaporizes. |
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W |
Wafer
Round silicon disc containing numerous integrated
circuits.
Waffle Tray Tray. Flat plastic
matrix component carrier.
Water Soluble Flux Flux usually containing
organic acids and no rosin. Classified OA.
Wave Soldering A soldering process where
the PCB′s are soldered by passing a wave of molten
solder alloy.
Wedge Bonding A specific method used attaching
aluminium or gold wires between the
pads of a bare IC and the component lead.
Wetting The solder alloys ability to flow
and wet a metal surface.
Wetting Balance An instrument used to
measure wet ability.
Wire Bonding A die connection method attaching
aluminium or gold wires between the
pads of a bare IC and the component lead. |
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X |
X-axis
One of the horizontal movement axis. Typically
left and right.
X-Ray A ray of photons. Used in inspection
machines for internal inspection of PCB′s and solder
joints. |
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Y |
Yield
First Pass Yield. Finished units (in percent)
not requiring rework.
Y-axis One of the horizontal movement
axis. Typically forward and backward. |
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Z |
Z-axis
The vertical movement axis in a placement or
dispensing machine. |
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