| Term |
Definition |
| D |
back to top |
| D-AMPS (Digital-Advanced
Mobile Phone System) |
Earlier designation of American standard for digital mobile telephony
used primarily in North America, Latin America, Australia and parts
of Russia and Asia. Also known as (North America) TDMA.
|
| DAC or D/A Converter |
see Digital-to-Analog Converter |
| dB (deciBel) |
A technique for expressing voltage, power, gain, loss or frequency
in logarithmic form against a reference. Typical references include
volts and watts of Hz. DeciBels are calculated using the expression:
dB = 10*log(x/y).
|
| dBi (deciBels referenced to
an isotropic antenna) |
A technique for expressing a power gain measurement in logarithmic
form using a theoretical isotropic antenna as a reference.
|
| dBm (deciBels referenced to
a milliWatt) |
A technique for expressing a power measurement in logarithmic
form using 1 mW as a reference.
|
| DCS |
see Distributed Control System |
| DECT (Digital European Cordless
Telecommunications) |
A common standard for cordless personal telephony originally
established by ETSI, a European standardization body. Standard based
on a micro-cellular radio system that provides low-power cordless
access between subscriber and base station up to a few hundred meters.
|
| Defect |
Any nonconformance to specified requirements by a unit or product. |
| Defluxing |
Cleaning. Removing flux residues after a soldering operation. |
| Degreasing |
Cleaning. Removing wave oil and flux residues after a soldering
operation |
| Delamination |
A separation of the bonded layers or foils of a laminated material,
such as a printed circuit board. |
| Dense
Wavelength Division Multiplexing (DWDM) |
Key enabling technology that increases bandwidth capacity by
combining beams of light of slightly different wavelengths through
a single fiber, with each fiber carrying its own stream of information. |
| Density |
The weight of a material in relationship to its volume. |
| Deposition |
The process of applying a material on a substrate by applying
pressure through a screen or stencil. |
| Design Qualification |
Verification through test and analysis that a PCB design will
perform its required operations functions.
|
| Depot Repair |
A method of repairing electronic equipment in which the customer
ships a damaged product to a central location for repair, as opposed
to field repair in which the EMS provider (or other service organization)
visits the customer. |
| Design Reviews |
Checkpoints established at critical points in the design process
to verify the validity of the design and its associated data and
documentation, and evaluate the producibility, testability, and
projected reliability of the product.
|
| Design Rules |
Allowable dimensions, keepout areas, and tolerances used in the
layout and design of circuitry. |
| Design Standards |
Layout processes, guidelines, and procedures that are widely
used throughout the printed circuit industry.
|
| Design Validation |
Provides a process that subjects a design to a series of stress
tests to determine its robustness |
| Design-for-Manufacturability
(DFM) |
Design-for-manufacturability consists of designing a product
that functions well and is as efficient as possible to manufacture.
This often requires the engineering and manufacturing teams of an
organization to work together to design the product, choose the
components, etc. |
| Design-for-X (DFx) |
The value-added service of instituting "best practices" in the
design stage to improve X, where X is manufacturability, testability,
serviceability, etc. |
| Desoldering |
A disassembly method of removing the solder from components on
a printed circuit board. |
| Device |
see Component |
| DFF |
Design for fabrication.
|
| DFM |
see Design-for-Manufacturability |
| DFT |
Design for test.
|
| DFx |
see Design-for-X |
| Die |
Integrated circuit chip as diced or cut from the finished wafer. |
| Die Attach |
Bonding a die to its mount in its package. This is often done
with a metal based glue-like silver epoxy for good conduction of
heat away from the chip. |
| Die Bonding |
see Bonding, Die |
| Die Casting |
A production casting process for metals.
|
| Dielectric |
Nonconducting material used to encapsulate circuitry and in the
manufacturing of capacitors and printed circuit boards. |
| Differential
Scan Calorimetry |
Implies two possible values usually given by binary values, 0
or 1. |
| Digital |
Describes when information (speech, for example) is encoded before
transmission using a binary code, discrete, non-continuous values.
Digital networks are rapidly replacing analog ones as they offer
improved sound quality, secure transmission and can handle data
as well as voice. Digital networks include mobile systems GSM 900,
GSM 1800, GSM 1900, D-AMPS and the cordless DECT system.
|
| Digital-To-Analog
Converter (DAC or D/A Converter) |
A device that converts digital information into a corresponding
analog voltage or current. |
| DIP |
see Dual Inline Package |
| Direct Chip Attach
(DCA) |
Chip-on-board technology. |
| Direct Die Attach
(DDA) |
Direct Chip Attach |
| Direct order
fulfillment (DOF or direct delivery) |
Delivering a customer's product to the end-user saves logistics
costs and time-to-market. Other fulfillment elements include assembling
and packaging a product to the customer's configuration including
document kits written in a specified language. |
| Dispense (ing) |
A machine or manual method of applying solder paste, adhesives,
and other gels using air or mechanical pressure to force the material
being dispensed through a nozzle or tip onto a substrate. |
| Dispersion |
Signal distortion caused by a spreading of an optical pulse in
time as it propagates along the length of the fiber. Increasing
fiber optic transmission speeds are driving increased dispersion
effects. |
| Distributed
Control System (DCS) |
A real-time control system for continuous and batch process applications. |
| Dock-to-stock |
A supplier quality management practice that allows a component
or product to enter into a company without going through an incoming
inspection upon arrival at the receiving dock. |
| DOD (Department of Defense) |
A government office that issues standards similar to Mil-Spec.
|
| DOE |
Design of Experiment.
|
| Double-sided |
A circuit board with conductive patterns on both external surfaces.
|
| Double
Sided Reflow Soldering |
see Reflow
Soldering, Double Sided |
| Double-Sided
Assembly |
A printed circuit assembly with components on both sides of the
substrate. |
| DPM |
Defects Per Million |
| Drill Files |
Precise x-y location and sizes of all holes required on a printed
circuit board. |
| Drill Wander |
In printed circuit board fabrication, deviation from the target
drilling location. |
| Dry Etching |
Plasma Etching |
| Dry Film (Solder Mask) |
Solder Mask, Dry Film |
| Dry Run (ning) |
Operating a machine without processing. For instance, dry running
a placement machine sequentially moves the head to the feeders and
the component placement locations. |
| DSC |
see Differential Scan
Calorimetry |
| DSP |
Digital Signal Processing |
| Dual Inline Package
(DIP) |
A PTH package with two parallel rows of leads extending from
the base of the component. Standard lead pitch is 0.100 inch. |
| DWDM |
see Dense Wavelength
Division Multiplexing |
| E |
back to top |
| ECN (Engineering Change Notice) |
A means for documenting changes.
|
| ECO (Engineering Change Order) |
A means for requesting engineering changes.
|
| ECTC |
Electronic Component Technology Conference.
|
| EDFA |
see Erbium-Doped Fiber
Amplifier |
| Edge Clearance |
A keepout area on the side and each ends of printed circuit boards
required for board handling. |
| Edge Connector |
The portion of the PCB used to provide an external electrical
connection. |
| EDI |
Electronic Data Interchange is a standard for automated exchange
of business documents. Using EDI, purchasers and suppliers can exchange
digital paperwork including purchase orders, invoices, and other
business documents, and perform electronic funds transfers |
| EIA (Electronic Industry Association)
|
A trade association and standards setting organization in the
USA.
|
| EIAJ |
Electronic Industries Association of Japan |
| Electrochemical
Migration |
An unplanned electrolytic plating process. A film of polar solvent,
often water, on a substrate surface provides for current flow between
points with a difference in electrical potential. |
| Electroless
Nickel-Immersion Gold (ENIG) |
A coating applied during printed circuit board fabrication to
protect copper features from oxidation. |
| Electroless
Plating |
see Plating,
Electroless |
| Electromagnetic
Compatibility (EMC) |
This is the ability of a system, such as a computer, to operate
without producing polluting interference (EMI), so that you can
use, for example, your computer or radio or hairdryer without causing
interference to your TV set. Since January 1992, most electrical
products sold in the EEC have had to comply with new laws which
limit the interference that can be produced. [EMI, RFI] |
| Electromagnetic
Interference (EMI) |
Every electric current that flows produces a magnetic field.
If the current increases or decreases, the magnetic field grows
or shrinks. If this moving magnetic field passes through a wire,
a voltage signal will be induced in the wire which may interfere
with the correct operation of the circuit of which the wire forms
a part. Strong magnetic fields occur where cables carry heavy current,
so special attention must be given, for example, to the design of
the computer's power supply. If electric currents are changing rapidly,
radio waves can be generated which may cause interference with other
equipment. [EMC, RFI] |
| Electrostatic
Discharge (ESD) |
The transfer of a charge when the two objects have different
electrostatic potentials. The potentials can be caused by either
direct contact or induced by an electrostatic field. In electronic
manufacturing, the employee working on a printed circuit board and
a component on the same board can have different electrostatic potentials,
which will damage electronic components. |
| Embedded Computer |
Embedded computers are board level systems that contain one or
more microprocessors and act as the "brains" inside telecom, manufacturing,
medical, and electronic products. |
| EMC |
see Electromagnetic Compatibility |
| EMI |
see Electromagnetic Interference |
| EMS |
Electronic Manufacturing Services |
| EMS Provider |
An EMS provider offers manufacturing services as part of strategic
business relationship with its customers that helps OEMs extend
their business operations. EMS companies typically perform an entire
manufacturing segment service such as PCB assembly or cable harness
assembly for the OEM. The OEM may complete the final system assembly
and test, or it may decide to outsource all of the manufacturing
functions to an EMS provider. An OEM's relationship with an EMS
provider is typically longer in duration than a CM transaction. |
| Encapsulating |
Potting. Enclosing an article in an envelope of adhesive. |
| Encapsulating
Compound |
An electrically nonconductive compound used to completely enclose
and fill in voids between electrical components or parts. |
| Enclosure |
A metal or plastic case that serves the components that reside
inside a piece of electronic equipment. |
| Encoder |
A precision glass or metal ruler mounted on the frame of a machine
that is used to measure the location of a moveable head. Encoders
can be either linear or rotary. |
| End of life
manufacturing |
Generally involves the support of low volume new build to support
service demand where the return rates from service do not support
the service demand rate. Will involve BOM management, AVL management,
material recovery, order management, manufacturing tool archives. |
| ENIG |
see Electroless Nickel-Immersion
Gold |
| Enterprise
Resource Planning (ERP) |
(1) An attempt to extend the discreditted MRP approach into
personnel and financial planning. (2) A computer system designed
to facilitate ERP, such as Baan, SAP, or PeopleSoft.
|
| Environmental
Stress Screening (ESS) |
A process by which components or assemblies are tested at the
extremes of their normal operating conditions, usually in terms
of temperature and voltage limits, for a period of hours or days
in order to detect early life defects. It is not meant to be a destructive
test. |
| Erbium-Doped
Fiber Amplifier (EDFA) |
An optical amplifier based on an optical fiber doped with a small
amount of the rare earth element erbium. When this fiber is illuminated
with an appropriate laser source "pump laser", it serves
to boost or amplify optical signals. |
| ERP |
see Enterprise Resource
Planning |
| ESD |
see Electrostatic Discharge |
| ESD Sensitive |
Electrical and electronic parts, assemblies and equipment that
could be damaged by ESD voltages. |
| ESS |
see Environmental stress
screening |
| Etch Factor |
The ratio of etch depth to the amount the resist is undercut
during etching. |
| Etching |
The process of selectively removing any material not protected
by a resist using an appropriate solvent or acid. |
| Extinction Ratio |
Extinction ratio is a measure of the amplitude of the digital
modulation on the optical carrier and so affects the power penalty,
or distance over which a fiber-optic system can reliably transmit
and receive a signal. |
| Extranet |
Electronic Data Interchange is a standard for automated
exchange of business documents. Using EDI, purchasers and suppliers
can exchange digital paperwork including purchase orders, invoices,
and other business documents, and perform electronic funds transfers. |
| Extrusion |
A process of forming metal and plastic materials which are forced
through a die to form a uniform cross-section.
|
| F |
back to top |
| Fab |
Fabrication. A “fab” can refer to either the fabricator or the
printed circuit board made by the fabricator. |
| Failure |
The temporary or permanent functional impairment of a component
or device caused by physical, mechanical, chemical, or electrical
damage. |
| Failure
Mode Effect Analysis (FMEA) |
A structured evaluation of the impact of a failure on product
or process functionality, safety, usability, maintainability, availability,
and testability. |
| Fault Tolerance |
The ability to execute tasks regardless of the failure of strategic
components. |
| FBGA |
Fine-Pitch Ball Grid Array |
| FBGA
flange package. Fixed body size CSP |
A substrate that extends beyond the boundaries of the die. The
package retains its board footprint, regardless of die size. |
| FBGA real chip
size |
CSP in which the package dimension is closely related to the
die size. The package shrinks every time there is a die shrink. |
| FCC (Federal Communications
Commission) |
Regulatory body governing communications technologies in the
US. Established by the Communications Act of 1934, as amended, and
regulates interstate communications (wire, radio, telephone, telegraph
and telecommunications) originating in the United States.
|
| FCIP |
Flip Chip In Package |
| FCT |
Flip Chip Technology |
| FDD |
Floppy disk drive.
|
| FDDI |
Fiddi Fibre-Distributed Data Interface |
| FEA |
Finite Element Analysis.
|
| Feeder |
A machine that supplies tape and reel components in the proper
orientation and sequence for picking by a pick and place head. |
| Feeder, Intelligent |
A feeder with a control system intended to reduce set-up and
inventory control errors. |
| Feeder, Tray |
A machine that supplies tray components in the proper orientation
and sequence to a pick and place head. |
| FEM (Finite-element Modeling)
|
A method of using a software program to simulate the response
of the PCB to various mechanical or thermal conditions. A mathematical
model of an assembly is constructed, exposed to mechanical or thermal
stimulation, and analyzed for its response to those inputs. |
| FESEM |
see Field
Emission Scanning Electron Microscope |
| FIB |
see Focused Ion Beam |
| Fiber Bragg Grating
(FBG) |
An FBG is essentially a filter, and can act like a mirror for
particular wavelengths. It is a piece of fiber treated with two
interfering beams of ultraviolet light that form an interference
pattern within the core of the fiber. The interference pattern allows
particular wavelengths to reflect. FBGs are also used in dispersion
compensation, and gain flattening. |
| Fiber Fusion/Splicing |
Fiber fusion/splicing is performed by a machine that applies
localized heat sufficient to fuse or melt the ends of two lengths
of optical fiber, forming a continuous single fiber. Fusion splicers
also typically incorporate alignment and test capabilities to ensure
a successful connection. |
| Fiber Optics |
Similar to a light pipe that uses strands of material to direct
light.
|
| Fiber Polisher |
A device used to polish the end face of a fiber to a specified
surface finish in order to ensure a successful fiber-to-fiber connection.
Critical function for the manufacturing of fiber-optic connectors. |
| Fiber Stripper/Recoater |
A stripper is used to remove the outer cladding of an optical
fiber without damaging the fiber core. A recoater is used to replace
the primary coating on spliced optical fibers. |
| Field
Emission Scanning Electron Microscope (FESEM) |
A conventional SEM, except that a cold field emission electron
source is used, providing higher image resolution, increased signal
to noise ratio, and increased depth of field. |
| FIFO |
First-in-first-out |
| Final Assembly |
Multiple definitions: 1) Completion of product assembly as contracted
or agreed upon (with customer). 2) The process comprised of a subset
or all of these manufacturing steps: fabricating and assembling
the mechanical components and subassemblies of the final product,
assembling one or more printed-circuit board (PCB) assemblies and
other components into a or subassembly, integrating all PCB assemblies
and subassemblies into a finished product. 3) Complete assembly
of end product (including testing, and preparing for shipping),
commonly referred to as "box build".
|
| Fine Line Etching |
A method for etching with minimal undercut, generally results
in slightly slower etch rates and involves etchants with lower chloride
contents and lower pH to protect dry film. |
| Fine Pitch |
Refers to components with terminations on less than .025-in centers.
|
| Firmware |
A program permanently recorded in ROM; it is effectively a piece
of hardware that performs software functions. |
| First Pass Yield |
The percent of finished assemblies not requiring rework. |
| FIT |
Failures in time per 109 hours.
|
| Fixture |
A mechanical means of holding something for assembly, machining,
silk-screening, etc.
|
| Flatpack |
A part with two straight rows of leads (normally on 0.050 inch
centers) that are parallel to the part body. |
| Flexible
circuit assembly |
Integration of active and passive components on a flexible substrate.
Flexible circuits are ideal for miniature products or hard-to-reach
areas that require a PCB. |
| Flexible
Printed Circuit Board |
A printed circuit board laminate made dielectric polymer film,
adhesive, and conductive foil. |
| Flip Chip |
A COB technology
that has bumps attached to the silicon die, is flipped, and mounted
directly to a printed circuit board. |
| Flip Chip Bonding |
Flip chip is a method of interconnecting devices by directly
attaching the device to the substrate, thus allowing a much higher
density of interconnections versus wire bonding. |
| Flip-chip Device |
A leadless, monolithic, circuit element (chip) that is electrically
and mechanically interconnected to a conductor pattern on a board
through the use of conductive bumps on the chip. The bumps are formed
on the active surface of the chip, which is turned over (flipped)
for attachment. |
| Flux |
A material used in conjunction with soldering that removes oxidation
on surfaces to be soldered and prevents reoxidation during the formation
of a solder joint. |
| Flying Probe |
A rigid, pointed, metallic, wire-shaped device used for making
electrical contact to a circuit pad for electrical test purposes.
|
| FM (Frequency Modulation) |
A form of angle modulation in which the instantaneous frequency
of a sine-wave carrier is caused to depart from the carrier frequency
by an amount proportional to the instantaneous value of the modulating
wave.
|
| FMEA |
see Failure Mode and Effect
Analysis |
| Focused Ion Beam
(FIB) |
A “milling machine” that uses ions. Like a SEM, a sample is put
in a chamber under vacuum, beneath a column which scans a focused
beam of charged particles over the sample surface. In a FIB, the
charged particles are ions (typically gallium) generated by a liquid
metal source. The ions collide with and sputter away atoms of the
sample in the scanned region. This beam can slice into the sample
with great accuracy. Like in an SEM, a detector in the chamber collects
secondary species (ion or electron) for imaging. Resolution is fine
enough to image ICs. |
| Footprint |
The hole, pad and conductor pattern associated with a specific
electronic component package configuration. |
| FPT |
see Fine Pitch |
| FRP (Fiberglass Reinforced
Plastic) |
Common material for PCB's.
|
| FTIR |
Fourier Transform IR |
| FTP |
An area of a Web site available only to a set of registered
visitors. |
| Fulfillment |
A process that supplies a finished manufactured product directly
from a manufacturing facility to a distributor or end user without
the finished product going back through the company that has created
the product. The fulfillment cycle may include receiving customer
orders, configuring the products to order, shipping and invoicing
products to distribution outlets or end users around the world. |
| Full system
assembly |
For a personal computer, this entails assembling a PCB, placing
the board inside a card cage or enclosure together, and downloading
the appropriate software. Next, the fully assembled product is placed
inside a cardboard box, loaded on a third-party delivery truck and
shipped to its desired destination. Manufacturing test and factory
installation of software are often included in this process. Full
system assembly usually has lower than average margins because of
its high material content (plastic, metal, etc.) |
| Functional Testing |
The electrical testing of an entire assembly that simulates the
inteded function of the product.
|
