IPC-T-50F_.pdf.pdf - 第28页
Download, Tester 92.0403 The ability of a test analyzer to provide failure analysis and data logging information to a host computer . Drafting Image 26.0404 An image that is part of a master drawing or layout. Drag Solde…
Dimensioned Hole 22.0382
A hole in a printed board whose location is determined by
physical dimensions or coordinate values that do not nec-
essarily coincide with the stated grid.
Dimorphism 40.0383
The existence of a substance in two different crystalline
forms.
Dip Soldering 75.1382
The making of soldered terminations simultaneously by
bringing the solder side of a printed board with through-
hole mounted components into contact with the surface of
a static pool of molten solder. (See also ‘‘Drag Soldering.’’)
Diphase Cleaning 76.0384
Cleaning by means of solutions that contain a solvent layer
and an aqueous layer.
Dipole 21.0385
An assemblage of atoms or subatomic particles, separated
by a finite distance, that have equal electric charges of
opposite sign.
Dipole Moment 21.1383
Molecules in which the atoms, their electrons, and their
nuclei, that are so arranged that one part of the molecule
has a positive electrical charge while the other part is nega-
tively charged.
Direct Dimensioning 22.0388
The maximum variation between two features that is con-
trolled by the tolerance on the dimension between the fea-
tures.
Direct Cleaning 76.0386
see ‘‘Cathodic Cleaning’’
Direct Current (DC) 21.1796
A current produced by a voltage source that does not vary
with time and is normally provided by power supplies,
transformers or batteries to power electronic circuits.
Direct Current Cleaning 76.0387
see ‘‘Cathodic Cleaning’’
Discrepant Material 92.0389
Material that does not conform to specification.
Discrete Component 30.0392
A separate part of a printed board assembly that performs
a circuit function, e.g., a resistor, a capacitor, a transistor,
etc.
Discrete Wiring Board 64.0390
A base material upon which discrete wiring techniques are
used to obtain electrical interconnections.
Discrete Wiring Board Assembly 64.0391
An assembly that uses a discrete wiring board for compo-
nent mounting and interconnecting purposes.
Dispersant (Organosol) 41.0393
A liquid component that has a solvating or peptizing action
on a resin so as to aid in dispersing and spreading it.
Disperse Phase (Suspension) 41.0394
The particles of solid material dispersed in a liquid
medium.
Dispersing Agent 41.0395
A surface-active agent added to a suspending medium to
promote uniform separation of extremely-fine solid par-
ticles.
Dissipation Factor 21.0396
A value that represents the tendency of insulating or dielec-
tric materials to absorb some of the energy in an
alternating-current signal.
Dissolution of Metallization 36.1741
The process of dissolving metal, usually by introduction of
chemicals. (See also ‘‘Leaching, Metallization’’).
Distributed Numerical Control (DNC) 25.0398
A network that links computer programs or computer-aided
systems to numerically-controlled machine tools.
Disturbed Solder Connection 97.1384
A solder connection that is characterized by the appearance
that there was motion between the metals being joined
when the solder was solidifying.
Don’t Care Area 22.0399
see ‘‘Exclusion Area’’
Doping 35.0400
The addition of an impurity to alter the conductivity of a
semiconductor die.
Double-Sided Assembly 80.0401
A packaging and interconnecting structure with compo-
nents mounted on both the primary and secondary sides.
(See also ‘‘Single-Sided Assembly’’)
Double-Sided Printed Board 60.0402
A printed board with a conductive pattern on both of its
sides.
Download, Computer 11.1385
The transfer of computer programs or data from a com-
puter to a lower- level computer. Expert System - Software
that applies human-like reasoning to solve a problem by
the use of rules and heuristics.
June 1996 IPC-T-50F
23
Download, Tester 92.0403
The ability of a test analyzer to provide failure analysis and
data logging information to a host computer.
Drafting Image 26.0404
An image that is part of a master drawing or layout.
Drag Soldering 75.1386
The making of soldered terminations by moving the solder
side of a supported printed board with through-hole
mounted components through the surface of a static pool of
molten solder. (see also ‘‘Dip Soldering.’’)
Drain Wire 37.0405
An uninsulated wire that is used for the electrical termina-
tion of a shield or ground plane.
Drawbridged Component 73.0406
see ‘‘Tombstoned Component.’’
Drill Body Length 51.0407
The distance from the drill point to the intersection of the
drill diameter and shoulder angle.
Drill Diameter 51.0408
The actual size of the drill body.
Drill Point Concentricity 51.0409
The total variation of the location of the chisel point of a
rotated drill shank.
Dross 75.0410
Oxide and other contaminants that form on the surface of
molten solder.
Dual Fixture 92.0411
A test fixture with two separate bed-of-nails units.
Dual-Inline Package (DIP) 31.1387
A basically-rectangular component package that has a row
of leads extending from each of the longer side of its body
that are formed at right angles to a plane that is parallel to
the base of its body.
Dual-Strip Line 21.1797
A stripline signal conductor embedded between two ground
planes or between two ground conductors on the same
plane and is not necessarily centered between the ground
references.
E
E Glass 44.0423
A low alkali lime alumina borosilicate glass with good
electrical properties.
Edge Definition 92.0415
The reproduction fidelity of a pattern’s edge relative to the
production master.
Edge Detection 92.0416
The ability to recognize (differentiate) the location of an
edge.
Edge Rate 21.0417
The rate of change in voltage with time of a logic signal
transition.
Edge Short 74.0418
An electrical short caused by carrier tape leads making
contact with the edge of a semiconductor die.
Edge Spacing 22.0419
The distance of a pattern or component body from the
edges of a printed board. (See also ‘‘Margin.’’)
Edge-Board Connector 37.0412
A connector that is used specifically for making nonperma-
nent interconnections with the edge-board contacts on a
printed board.
Edge-Board Contact(s) 22.0413
Printed contact(s) on or near any edge of a printed board,
that are used specifically for mating with edge-board con-
nectors.
Edge-to-Edge Spacing 22.0414
see ‘‘Conductor Spacing Line’’
Edge-Transition Attenuation 21.1388
The loss of a logic signal’s switching-edge sharpness that
has been caused by the absorption of the highest-frequency
components by the transmission line.
Effective Color Temperature 24.0420
A color temperature based on an approximation of an
equivalent continuous spectrum resultant source, expressed
in degrees Kelvin (K).
Effective Focal Length 24.0421
A measure of the distance from the principal point of a
magnification device’s optical system to the corresponding
focal point.
Effective Permittivity 21.0422
see ‘‘Dielectric Constant.’’
Effective Relative Dielectric Constant 21.1798
The value of the dielectric constant obtained when experi-
mentally determined in an application as opposed to mea-
sured values of sample material.
IPC-T-50F June 1996
24
Elastomeric Connector 36.0424
A pliant strip of flexible material with insulating and con-
ductive elements intended for providing electrical intercon-
nections.
Electrical Characteristics 21.1742
The distinguishing electrical traits or properties of a com-
ponent or assembly.
Electrodeposited Foil 45.0425
A metal foil that is produced by electrodeposition of the
metal onto a material acting as a cathode.
Electrodeposition 53.0426
The deposition of a conductive material from a plating
solution by the application of electrical current.
Electroless Deposition 53.0427
The deposition of conductive material from an autocata-
lytic plating solution without the application of electrical
current.
Electroless Plating 53.0428
see ‘‘Electroless Deposition.’’
Electrolytic Cleaning 76.0429
Cleaning in which a current is passed through an alkaline
solution with the part to be cleaned being one of the elec-
trodes.
Electrolytic Deposition 53.0430
see ‘‘Electrodeposition.’’
Electromagnetic Interference (EMI) 21.0431
Unwanted radiated electromagnetic energy that couples
into electrical conductors.
Electron-Beam Bonding 74.0432
Terminations made by heating with a stream of electrons in
a vacuum.
Electroplating 53.0433
see ‘‘Electrodeposition.’’
Elementary Diagram 26.0434
A computer-generated schematic diagram with annotations.
Elongation 70.0435
The increase in length of a material that is caused by a ten-
sile load.
Embedded Component 30.0436
A discrete component that is fabricated as an integral part
of a printed board.
Emulsifying Agent 76.0437
A substance that increases the stability of an emulsion.
Emulsion 76.0439
A stable mixture of two or more immiscible liquids held in
suspension by small percentages of emulsifiers.
Encapsulant 76.0440
see ‘‘Potting Compound.’’
End Item 20.0441
see ‘‘End Product.’’
End Product 20.0443
An individual part or assembly in its final completed state.
End Missing 44.0442
A very small portion of the warp in a fabric that may have
been broken in the pick-out of waste material.
Engineering Drawing 26.0444
A document that discloses the physical and functional end-
product requirements of an item by means of pictorial
and/or textual presentations.
Epoxy Glass Substrate 41.1743
A two-part epoxy resin that polymerizes spontaneously
when the two components are mixed, combined with glass
fiber to form a substrate
Epoxy Novolac 41.0445
A multifunctional resin having epoxy groups attached to a
novolac group(s).
Epoxy Smear 51.0446
see ‘‘Resin Smear.’’
Equivalent Series Resistance (ERS) 21.0447
A loss parameter used to compare two capacitors of equal
value in order to determine their relative effectiveness as
filters.
Escape Rate 94.0448
The ratio of the number of defective items not detected to
the total number inspected, expressed as a percentage.
Escapes 94.0449
Critical defects that are missed by an inspection system.
Etch Factor 54.0452
The ratio of the depth of etch to the amount of lateral etch,
i.e., the ratio of conductor thickness to the amount of
undercut.
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