IPC-T-50F_.pdf.pdf - 第72页

Terminal Hole 22.1054 see ‘ ‘Component Hole.’ ’ Terminal Pad 22.1055 see ‘ ‘Land.’ ’ Terminations 22.1773 T o connect a line to a terminal, distributing frame, switch or matrix. Terpenes 76.1774 (T urpentine). A solvent …

Supporting Plane 44.1032

A planar structure that is a part of a packaging and inter-

connecting structure in order to provide mechanical sup-

port, thermo-mechanical constraint, thermal conduction

and/or electrical characteristics. (It may be either internal

or external to the packaging and interconnecting structure.)

(See also ‘‘Constraining Core.’’)

Surface Insulation Resistance (SIR) 92.1538

The electrical resistance of an insulating material between

a pair of contacts, conductors or grounding devices in vari-

ous combinations, that is determined under speciﬁed envi-

ronmental and electrical conditions.

Surface Mounting 73.1035

The electrical connection of components to the surface of a

conductive pattern that does not utilize component holes.

Surface Mount Device (SMD) 30.1772

See ‘‘Surface Mount Component (SMC)‘‘.

Surface Tension 75.1036

The natural, inward, molecular-attraction force that inhibits

the spread of a liquid at its interface with a solid material.

Surface-Mount Component (SMC) 30.1034

A leaded or leadless device (part) that is capable of being

attached to a printed board by surface mounting.

Surge 21.1037

A transient variation in the current and/or potential at a

point in a circuit.

Swaged Lead 72.1539

A component lead wire that extends through a hole in a

printed board and its lead extension is ﬂattened (swaged) to

secure the component to the board during manufacturing

operations.

Swell-and-Etch Process 53.1540

The surface treatment of a base material in order to pro-

mote the adhesion of an electroless metal deposit by soft-

ening the surface with a solvent and then exposing the sur-

face to an oxidizing solution in order to create a

microporous surface.

Synthetic Activated Flux 75.1038

A highly-activated organic ﬂux whose post-soldering resi-

dues are soluble in halogenated solvents.

Synthetic Resin 75.1039

A synthetic organic polymer or a chemically-treated natu-

ral resin.

System Effective Color Temperature 24.1040

The effective color temperature measured using an optical

system’s light source to illuminate the target area.

Tab 22.1042

see ‘‘Printed Contact.’’

TAB 75.1041

see ‘‘Tape Automated Bonding.’’

Tail, Bonding 75.1043

The free end of wire extending beyond the bond impres-

sion of a wire bond from the heel.

Tail Pull 75.1044

The removal of excess wire after a wedge or ultrasonic

bond is made.

Tape 75.1045

see ‘‘Carrier Tape.’’

Tape Automated Bonding 75.1046

A ﬁne-pitch technology that provides interconnections

between die and base materials with conductors that are on

a carrier tape.

Taped Component 71.1541

A component that is attached to a continuous tape in order

to facilitate the use of automatic component incoming

inspection, lead forming, assembling and testing.

Tear (Fabric) 44.1047

A large rip in a fabric that is usually caused by excessive

tension being applied during processing or caused by a

weakness in the fabric.

Temperature Profile 75.1048

The depiction of the temperature that a selected point

traverses as it passes through the reﬂow process.

Tenter Frame 44.1049

A machine test maintains fabric width during drying by

means of clips running on two parallel endless chains.

Tenting 52.1050

The covering of holes in a printed board and the surround-

ing conductive pattern with a resist.

Terminal 37.1051

A metallic device that is used for making electrical connec-

tions. (See also ‘‘Solder Terminal.’’)

Terminal Area 22.1052

see ‘‘Land.’’

Terminal Clearance Hole 22.1053

see ‘‘Access Hole.’’

June 1996 IPC-T-50F

Terminal Hole 22.1054

see ‘‘Component Hole.’’

Terminal Pad 22.1055

see ‘‘Land.’’

Terminations 22.1773

To connect a line to a terminal, distributing frame, switch

or matrix.

Terpenes 76.1774

(Turpentine). A solvent used in cleaning electrical assem-

blies.

Test Board 92.1683

A printed board or discrete-wiring board that is deemed to

be suitable for determining the acceptability of a group of

boards that were, or will be, produced with the same fabri-

cation processes. (See also ‘‘Capability Test Board.’’)

Test Coupon 92.1820

A portion of quality conformance test circuitry that is used

for a speciﬁc test, or group of related tests, in order to

determine the acceptability of a product.

Test Language 92.1057

A high-level language used to write a test program.

Test Master 92.1058

Artwork that contains speciﬁed anomalies or degrees of

defect that an inspection or testing system should be

capable of detecting.

Test Pattern 92.1059

A pattern that is used for inspection or testing purposes.

Test Point 92.1060

A special point of access to an electrical circuit that is used

for electrical testing purposes.

Test Program 92.1061

The set of instructions to a tester that controls the unit

under test.

Test Set 92.1062

The unique combination of test programs and test ﬁxtures

that control the unit under test.

Test Step 92.1063

The application of a single input vector.

Testing Personnel 92.1056

Those individuals that test products for the purpose of

ascertaining the conformance of a product to applicable

speciﬁcations.

Tetrafunctional Resins 75.1064

Materials that have four reactive groups per molecule.

Thermal Coefficient of Expansion (TCE) 21.1065

see ‘‘Coefficient of Thermal Expansion (CTE).’’

Thermal Conductivity 20.1066

The property of a material that describes the rate at which

heat will be conducted through a unit area of the material

for a given driving force.

Thermal Expansion Mismatch 20.1067

The absolute difference between the thermal expansion of

two components or materials. (See also ‘‘Coefficient of

Thermal Expansion (CTE).’’)

Thermal Relief 22.1068

The crosshatching of a ground or voltage plane that mini-

mizes blistering or warping during soldering operations.

Thermal Shunt 30.1069

see ‘‘Heatsink.’’

Thermal Zone 50.1542

A metal-integrity evaluation zone that extends a speciﬁed

distance beyond the ends of the lands in a microsection of

a vertical portion of a plated-through hole. (Unless other-

wise speciﬁed, the extended distance is 0.08 mm [0.003-

inch].)

Thermocompression Bonding 74.1543

The joining together of two materials without an interme-

diate material by the application of pressure and heat in the

absence of electrical current.

Thermode 75.1070

A contact heating element that is used to generate reﬂow

soldering heat.

Thermoplastic 40.1071

A plastic that can be repeatedly softened and reshaped,

without any signiﬁcant change in inherent properties, by

exposure to heat and hardened by cooling.

Thermoset 40.1544

A plastic that undergoes a chemical reaction when exposed

to elevated temperatures that leads to it having a relatively

infusable or crosslinked stated that cannot be softened or

reshaped by subsequent heating.

Thermosonic Bonding 74.1072

Terminations made by combining thermocompression and

ultrasonic bonding principles.

IPC-T-50F June 1996

Thick Film 45.1545

A ﬁlm, greater than 0.1 mm (0.004-inch) thick, deposited

by screen printing and subsequently ﬁred at high tempera-

tures in order to fuse it into its ﬁnal functional form.

Thick-Film Circuit 83.1073

A microcircuit in which passive components of a ceramic-

metal composition are formed on base material by screen-

ing and ﬁring.

Thick-Film Hybrid Circuit 83.1074

A hybrid circuit with thick-ﬁlm components and intercon-

nections.

Thick-Film Network 83.1075

A hybrid circuit comprised only of thick-ﬁlm components

and interconnections.

Thin Film 45.1079

A ﬁlm, less than 0.1-mm (0.004-inch) thick, deposited by

accretion process, such as vacuum or pyrolytic deposition.

Thin-Film Hybrid Circuit 83.1076

A hybrid circuit with thin-ﬁlm components and intercon-

nections. (See also ‘‘Hybrid Circuit.’’)

Thin-Film Integrated Circuit 83.1077

A hybrid integrated circuit comprised only of thin-ﬁlm

components and interconnections. (See also ‘‘Hybrid Inte-

grated Circuit.’’)

Thin-Film Network 83.1078

A hybrid circuit comprised only of thin-ﬁlm components

and interconnections.

Thin Foil 45.1080

A metal sheet that is less than 0.02mm (0.0007 inch) thick.

Thinner (Liquid) 76.1081

A nonactivated solvent or solvent system that is used to

replace evaporated solvent and to reduce the solids content

of another substance.

Thixotropic Ratio 49.1082

An indication of thixotropy in the form of the ratio of vis-

cosities measured at two different shear rates.

Thixotropy 49.1083

A property of a substance, e.g., an adhesive system, that

allows it to get thinner upon agitation and thicker upon

subsequent rest.

Three-Layer Carrier Tape 36.1546

The carrier for conductors used in tape-automated bonding

that consists of a dielectric layer, an adhesive, and a etched

metal-foil conductor layer. (See also ‘‘Multilayer Carrier

Tape,’’ ‘‘Single-Layer Carrier Tape,’’ and ‘‘Two-Layer Car-

rier Tape.’’)

Threshold 21.1084

The magnitude of intensity that delineates that a signal is

representative of a changed state.

Through Connection 22.1086

see ‘‘Interlayer Connection.’’

Through Migration 90.1087

see ‘‘Dendritic Migration.’’

Through-Hole Mounting 72.1085

The electrical connection of components to a conductive

pattern by the use of component holes.

Tie Bar 53.1088

see ‘‘Plating Bar.’’

Tinning 71.1089

The application of molten solder to a basis metal in order

to increase its solderability.

Titrometry 92.1090

see ‘‘Volumetric Analysis.’’

Tolerance 26.1091

The total amount by which a speciﬁc dimension is permit-

ted to vary.

Toleranced Dimension 26.1092

A dimension with a tolerance.

Tombstoned Component 73.1093

A defect condition whereby a leadless device has only one

of its metallized terminations soldered to a land and has the

other metallized termination elevated above and not sol-

dered to its land.

Tooling Feature 22.1547

A physical feature that is used exclusively to position a

printed board or panel during a fabrication, assembly or

testing process. (See also ‘‘Locating Edge,’’ ‘‘Locating

Edge Marker,’’ ‘‘Locating Notch,’’ ‘‘Locating Slot,’’ and

‘‘Tooling Hole.’’)

Tooling Hole 22.1094

A tooling feature in the form of a hole in a printed board

or fabrication panel.

June 1996 IPC-T-50F