IPC-T-50F_.pdf.pdf - 第52页

Overcoat 76.0815 A thin ﬁlm of insulating material that is applied over a semiconductor die for the purposes of mechanical and con- tamination protecticon. Overhang 60.0816 The sum of outgrowth and undercut. (See Figure …

Offset Terminal Area 22.0806

see ‘‘Offset Land.’’

Omnibus Ring 36.0807

see ‘‘Support Ring.’’

One-Piece Connector 37.0809

see ‘‘Edge-Board Connector.’’

One-Sided Board 60.0810

see ‘‘Single-Sided Printed Board.’’

Opacity 24.0811

The reciprocal of the transmittance ratio for a photographic

image.

Opaquer 24.1456

A material that, when added to a resin system, renders

laminate sufficiently opaque, so that the yarn or weave of

the reinforcing material cannot be seen with the unaided

eye using either reﬂected or transmitting light.

Open Circuit Potential 21.0814

The potential of a cell from which no current ﬂows in the

external circuit.

Open, Electrical (n.) 92.0812

A fault that causes two electrically-connected points to

become separated.

Open-Entry Contact 37.0813

A type of female connector contact that does not prevent

the entry of an oversized mating part. (See also ‘‘Closed-

Entry Contact.’’)

Open Point 51.1457

The amount of misalignment between the trailing edge of

the junction line between the primary and secondary drill-

point clearance angles when they are ahead of the drill

centerline.(See Figure O-1.)

Open Time 75.1194

The maximum duration of the interval from the application

of an adhesive to the formation of a satisfactory bond. (See

also ‘‘Working Time.’’)

Optical Image 24.1195

An image that is projected onto a viewing screen.

Organic Contamination 76.1196

A type of contamination derived from an organic sub-

stance.

Orthochromatic Emulsion 24.1197

A photographic emulsion that is spectrally sensitive to the

violet, blue, and green portions of the visible light spec-

trum.

Orthogonal-Array Experiment 91.1458

A balanced evaluation whereby the avarage effect of a fac-

tor is determined while the levels of all other factors in the

design are systematically changed.

Outer-Lead Bond (OLB) 74.1198

The connection between a conductor on a bonding tape and

the base material. (See also ‘‘Inner-Lead Bond.’’)

Outgassing 53.1199

The gaseous emission from a laminate printed board or

component when the board or the printed board assembly

is exposed to heat or reduced air pressure, or both.

Outgrowth 45.1459

The increase in size of one side of a conductor that is

caused by plating that is in excess of that delineated on the

production master. (See Figures O-2 and O-3.)

Output Vector 91.1228

The set of logic values, either expected or measured, for all

output points at a particular test step of a unit under test.

Overall Length 51.1200

The distance from the end of a drill shank to the cutting

end of the tool, including the point.

IPC-I-002327

Figure O–1 Open point

Open Point

▼

IPC-I-001044

Figure O–2 Outgrowth, overhang, and undercut

COPPER

OVERHANG

UNDERCUT

OUTGROWTH

TIN/LEAD

PLATING

CONDUCTOR WIDTH (ACTUAL)

CONDUCTOR WIDTH AS ON

PRODUCTION MASTER

Undercut and overhang as

observed by fabrication and

user (usually by cross-sectioning)



outgrowth as observed by all

(determined by measurement

from verticallyabove and

by comparison to the production

master)

June 1996 IPC-T-50F

Overcoat 76.0815

A thin ﬁlm of insulating material that is applied over a

semiconductor die for the purposes of mechanical and con-

tamination protecticon.

Overhang 60.0816

The sum of outgrowth and undercut. (See Figure O-3.) (If

undercut does not occur, the overhang is the same as the

outgrowth.)

Overheated Solder Connection 75.0817

A solder connection that is characterized by solder surfaces

that are dull, chalky, grainy, and porous or pitted.

Overlap (Film) 67.0818

The contact area between a ﬁlm component and a ﬁlm

conductor.

Overlap (Drill) 51.1229

The amount of misalignment between the trailing edge of

the junction line between the primary and secondary drill-

point clearance angles when they are behind the drill cen-

terline. (See Figures B-4 and O-4.) (See also ‘‘Layback.’’)

Overplate 53.1673

Conformal metallic deposition on a previously formed con-

ductive pattern or part thereof.

Oxide Transfer 41.0819

see ‘‘Treatment Transfer.’’

Oxygen Concentration Cell 76.0820

A galvanic cell resulting primarily from differences in oxy-

gen concentration.

Package 30.1460

The container for a circuit component, or components, that

is used to protect its contents and to provide terminals for

making connections to the rest of the circuit.

Package Cap 30.0821

A cuplike package cover.

Package Cover 30.0053

The cover that encloses the contents in the cavity of a

package in the ﬁnal sealing operation.

Package Lid 30.0822

A ﬂat package cover.

Packaging and Interconnecting Assembly 60.0823

The general term for an assembly that has components

mounted on either or both sides of a packaging and inter-

connecting structure.

Packaging and Interconnection Structure 60.1461

The general term for a completely processed combination

of base materials, supporting planes or constraining cores,

and interconnection wiring that are used for the purpose of

mounting and interconnecting components.

Packaging Density 20.1462

The relative quantity of functions (components, intercon-

nection devices, mechanical devices, etc.) per unit volume.

(This is usually expressed by qualitative terms such as

high, medium, and low.)

Pad 20.0824

see ‘‘Land.’’

Panchromatic Emulsion 24.0825

A photographic emulsion that is spectrally sensitive to all

portions of the visible light spectrum.

Panel 41.1463

A rectangular sheet of base material or metal-clad material

of predetermined size that is used for the processing of one

or more printed boards and, when required, one or more

test coupons. (See also ‘‘Blank.’’)

Panel Drawing 26.0826

A document that shows the production master with related

manufacturing patterns and artifacts that relate to the fabri-

cation of printed boards.

Panel Plating 53.0827

The plating of an entire surface of a panel including holes.

IPC-I-001043

Figure O–3 Outgrowth, overhang, and undercut

CONDUCTOR WIDTH

PLATING

CONDUCTOR WIDTH AS ON

PRODUCTION MASTER

BASE MATERIAL

RESIST

METAL FOIL

OUTGROWTH

PLATING

IPC-I-002326

Figure O–4 Overlap

▼

Overlap

IPC-T-50F June 1996

Para-aramid 44.1464

The generic term that describes ﬁbers that are made from

wholly- aromatic polyamide, amide polymers in which at

least 85 % of the amide linkages are directly attached to

two benzene rings at the para position in the polymer

chain.

Parallel Pair 22.0828

Two conductors that are side-by-side at a controlled spac-

ing.

Parallel-Gap Soldering 75.1465

The passing of an electrical current through a high-

resistance space between two parallel electrodes in order to

provide the energy required to make a soldered termina-

tion.

Parallel-Gap Welding 75.1466

The passing of an electrical current through a high-

resistance space between two parallel electrodes in order to

provide the energy required to make a welded termination.

Parameter Record 25.0829

A record that deﬁnes the characteristics of a subsequent set

of records such as job identiﬁcation, electrical description,

tolerances, etc.

Pareto Analysis 94.0830

A problem-solving technique whereby all potential prob-

lem areas or sources of variation are ranked according to

their contribution to the end result.

Partial Lift 74.0831

A bonded lead that has been partial removed from the

bonding area.

Partially-Clinched Lead 72.1467

A component lead that is inserted through a hole in a

printed board and is then formed in order to retain the

component in place and but not necessarily in order to

make metal-to-metal contact with a land prior to soldering.

(See also ‘‘Clinched Lead.’’)

Passivation 57.0832

The formation of an insulating layer to protect a surface

from contaminants, moisture and particulate matter.

Passive Base Material 44.0834

Base material, that does not exhibit transistance, that serves

as the physical support and thermal sink for ﬁlm circuits.

Passive Component (Element) 30.1468

A discrete electronic device whose basic character does not

change while it processes an applied signal. (This includes

components such as resistors, capacitors, and inductors.)

Passive-Active Cell 76.0833

A cell whose electromotive force is due to the potential

difference between a metal in an active state and the same

metal in a passive state.

Paste Flux 75.0836

A ﬂux formulated in the form of a paste to facilitate its

application. (See also ‘‘Solder Paste’’ and ‘‘Solder-Paste

Flux.’’)

Paste, Soldering 75.0835

A soldering method that uses a solder paste applied to the

land, device termination, or both.

Path 20.0837

see ‘‘Conductor.’’

Pattern 20.0838

The conﬁguration of conductive and nonconductive mate-

rials on a base material, and the circuit conﬁguration on

related tools, drawings and masters.

Pattern Area 20.0839

The section of a designated conﬁguration that includes the

pattern and background.

Pattern Plating 53.0840

The selective plating of a conductive pattern.

Peel Strength 92.0841

The force per unit width that is required to peel a conduc-

tor foil from a laminate perpendicular to the surface of the

substrate.

Percent Contribution 91.0842

The amount that a single factor contributes to a total varia-

tion, expressed as a percent.

Percent of the Field of View 92.0843

The speciﬁc part of interest of the minimum required ﬁeld

of view of a magniﬁcation device.

Perforated (Pierced) Solder Terminal 37.1469

A ﬂat-metal solder terminal with an opening through which

one or more wires are placed prior to soldering. (See Fig-

ure P-1.)

Perimeter Sealing Area 30.0844

The surface on the perimeter of the cavity of a package that

is used for attachment to the package cover.

Permanent Resist 52.0845

A resist that is not removed after processing, e.g., plating

resist that is used in a fully-additive process.

June 1996 IPC-T-50F