IPC-T-50F_.pdf.pdf - 第10页
Backdriving 92.0074 An in-circuit testing technique that drives digital circuitry outputs to a given logic level, by supplying pulses of suf- ficient electrical current magnitude in parallel with the out- puts, in order t…
IPC-I-001025
Note:
The term ‘‘Original’’ may be used to preface any of the drafting and photographic-tooling terms used in this figure. The
‘‘Original’’ is not usually used in manufacturing processes. In the event a ‘‘Copy’’ is made, the copy must be of sufficient accuracy to
meet its intended purpose if it is to take on the name of any one of the terms used in this figure. Other adjectives may also be used
to help describe the kind of copy, i.e., ‘‘nonstable,’’ ‘‘first generation,’’ ‘‘record,’’ etc.
Figure A–3 Simplified flow chart of printed board design/fabrication sequence
PARTS LIST
SCHEMATIC DIAGRAM
LOGIC DIAGRAM
END PRODUCT
PERFORMANCE & TEST
REQUIREMENTS
MASTER
DRAWING
TEST/
PERFORMANCE
SPECIFICATION
PRINTED BOARD
ASSEMBLY
DRAWING
ARTWORK
MASTER
(See note.)
PRODUCTION
MASTER
(See note.)
MULTIPLE IMAGE
PRODUCTION MASTER
(See note.)
PANEL OR
PRINTED BOARD
(RIGID OR FLEXIBLE)
HOLES &
PROCESS
DATA
ARTWORK
(See note.)
ASSEMBLY
SEQUENCE/
PROCESS DATA
PRINTED
BOARD
ASSEMBLY
STANDARDS
MANUFACTURING
CAPABILITIES
Circuit Design
Packaging Design
Documentation
Manufacturing
Assembly
Test
FABRICATION
PROCESS
SPECIFICATION
PRINTED BOARD
LAYOUT
June 1996 IPC-T-50F
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Backdriving 92.0074
An in-circuit testing technique that drives digital circuitry
outputs to a given logic level, by supplying pulses of suf-
ficient electrical current magnitude in parallel with the out-
puts, in order to overdrive the logic state conditions of the
next digital device inputs.
Backfill 36.0075
Filling a hybrid circuit package with a dry inert gas prior
to hermetic sealing.
Background (Artwork) 22.0076
The nonfunctional area of a phototool.
Background Variable 94.0077
A parameter of no experimental interest that is not held at
a constant value.
Backlighting 24.0078
Viewing or photographing by placing an object between a
light source and the eye or recording medium.
Backpanel 85.0080
see ‘‘Backplane.’’
Backplane 85.1331
An interconnection device used to provide point-to-point
electrical interconnections. (It is usually a printed board
that has discrete wiring terminals on one side and connec-
tor receptables on the other side.) (See also ‘‘Mother
Board.’’)
Backward Crosstalk 21.1332
Noise induced into a quiet line, as seen at the end of the
quiet line that is closest to the signal source, because the
quiet line has been placed next to an active line. (See also
‘‘Forward Crosstalk.’’)
Bake Out 56.0082
Subjecting a product to an elevated temperature in order to
remove moisture and unwanted gasses prior to certain steps
in the printed board manufacturing process or prior to final
coating.
Balanced Transmission Line 21.1333
A transmission line that has distributed inductance, capaci-
tance, resistance, and conductance elements that are
equally distributed between its conductors.
Ball Bond 74.0083
The thermocompression termination of the ball-shaped end
of an interconnecting wire to a land. (See also ‘‘Wedge
bond.’’)
Bar Code Marking 70.1731
An identification code consisting of a pattern of vertical
bars whose width and spacing identifies the item marked.
Bare Board 60.0084
An unassembled (unpopulated) printed board.
Barrier Metal 74.0085
A metal used to seal the semiconductor-die lands.
Base Material 40.1334
The insulating material upon which a conductive pattern
may be formed. (The base material may be rigid or flex-
ible, or both. It may be a dielectric or insulated metal
sheet.)
Base Material Thickness 22.1604
The thickness of the base material excluding conductive
foil or material deposited on the surfaces.
Base Metal 45.0088
see ‘‘Basis Metal.’’
Base Solderability 92.0089
The ease with which a metal or metal alloy surface can be
wetted by molten solder under minimum realistic condi-
tions.
Baseline Dimensioning 26.0086
The maximum variation between two features that is equal
to the sum of the tolerances on the two feature location
dimensions taken from the same origin. (See Figure B-1.)
Basic Dimension 26.1335
A numerical value used to describe the theoretical exact
location of a feature or hole. (It is the basis from which
permissible variations are established by tolerance on other
dimensions in notes or by feature control symbols.)
Figure B−1 Example of feature location using baseline
dimensions
IPC-T-50F June 1996
6
Basic Specification (BS) 26.1778
A document that describes the common elements for a set,
family or group of products, materials, or services.
Basic Statistical Method 91.1336
The application of a theory of variation through the use of
basic problem-solving techniques and statistical process
control. (This includes control and capability analysis for
both variables and attributes data.)
Basic Wettability 70.0090
The ease with which a metal or metal alloy can be wetted
by molten solder.
Basis Material 40.0091
Material upon which coatings are deposited.
Basis Metal 45.0092
A metal upon which coatings are deposited.
Batch Oven 56.0093
A large temperature-controlled oven that is used to heat
clean rolls of fabric.
Batch Processing 11.0094
Executing a computer-aided program without human input.
Batch Size 17.0095
see ‘‘Lot Size’’
Bathtub Curve 93.0096
A plot of failures versus time.
Baume 92.0097
An arbitrary scale of specific gravities used in the gradation
of hydrometers.
Beam Lead 33.0100
A component terminal in the form of a long metallic struc-
tural member that is not supported along its length.
Beaming 44.0099
The operation in which yarn from several section beams is
combined on the final warp beam.
Beam-Lead Device 33.0098
An active or passive chip component with beam leads for
interconnecting it to lands on a base material.
Bed-of-Nails Fixture 92.0101
A test fixture consisting of a frame and a holder containing
a field of spring-loaded pins that make electrical contact
with a planar test object.
Bellows Contact 36.1337
A type connector contact that consists of a flat spring that
has been folded to provide a very uniform spring rate over
the full tolerance range of the mating part.
Benchmark, Computer 11.0102
A standard measure of the performance of computers rela-
tive to each other, including set-up time, program genera-
tion, and data processing capability.
Benchmark, Testing 92.0103
A standard measure of the performance of testers relative
to each other, including set-up time, test program genera-
tion, and fixturing.
Beta Error 91.0104
The size of a Type II error or the probability of accepting
a hypothesis that is false.
Bias (Fabric) 44.0105
Filling yarn that is off-square with the warp ends of a fab-
ric.
Bifurcated Contact 36.1810
A type of connector contact that usually consists of a flat
spring that has been slotted length-wise in order to provide
independent contact points with the mating part.
Bifurcated Solder Terminal 37.0106
A solder terminal with a slot or slit opening through which
one or more wires are placed prior to soldering. (See Fig-
ure B-2.)
Binder 47.0107
Material added to thick-film compositions and unfired base
materials to give them additional strength for pre-fire han-
dling. (See also ‘‘Glass Binder.’’)
Binomial Distribution 94.0108
A discrete probability distribution that, with certain
assumptions, describes the variation of an attribute (propor-
tion).
Biochemical Oxygen Demand 92.0109
A standardized measure used for estimating the degree of
contamination of water.
IPC-0-001024
Figure B–2 Bifurcated solder terminal
June 1996 IPC-T-50F
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