IPC-T-50F_.pdf.pdf - 第51页

Offset Terminal Area 22.0806 see ‘ ‘Of fset 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.’ ’…

Nonactivated Flux 75.1183

A natural or synthetic-resin ﬂux without activators.

Nonconductive Pattern 22.1184

A conﬁguration that is formed by the functional noncon-

ductive material of a printed circuit, e.g., dielectric, resist,

etc.

Nonfunctional Interfacial Connection 22.1453

A plated through hole in a double-sided printed board that

electrically connects a printed conductor on one side of the

board to a nonfunctional land on the other side of the

board. (See Figure N-3.)

Nonfunctional Land 22.1185

A land that is not connected electrically to the conductive

pattern on its layer.

Nonfunctional Terminal Area 22.1186

see ‘‘Nonfunctional Land.’’

Nonionic Contaminant 76.1187

A residue that does not readily ionize in water.

Nonpolar Matter 76.1188

A substance that cannot be dissolved in water that is

soluble in hydrophobic solvents.

Nonpolar Solvent 76.1454

A liquid that is not ionized to the extent that it is electri-

cally conductive, that can dissolve nonpolar compounds

(such as hydrocarbons and resins), and cannot dissolve

polar compounds (such as inorganic salts.)

Nonwetting (Solder) 75.1189

The partial adherence of molten solder to a surface that it

has contacted and basis metal remains exposed. (See Fig-

ure N-4.)

Normal Distribution 94.1191

A mathematically-deﬁned continuous distribution of values

that has a bell shape that is perfectly symmetrical about a

mean value.

Normal-Mode Rejection (NMR) 21.1190

The amount of noise superimposed on the input signal of a

direct-current (DC) digital voltmeter that the instrument is

capable of rejecting.

Null Hypothesis 91.1455

The supposition that no signiﬁcant difference exists

between the desired results of two comparable populations.

(See also ‘‘Alternative Hypothesis’’ and ‘‘Statistical

Hypothesis.’’)

Numerical Control (machine) (NC) 25.1193

The automatic control of electromechanical devices by

means of a digital input to an electronic controller.

Numerical Control (math.) (NC) 20.1192

The use of mathematics to deﬁne, design or test geometric

quantities that are used in a computer-aided technology.

Object Code 25.0801

The output from a computer compiler or assembler that is,

or is suitable for, processing into executable machine

codes.

Object-Oriented Database 11.0800

A database that combines graphics and text to describe

objects.

Occluded Contaminant 76.0802

A contaminant that is totally contained in an insulating

material.

Occlusion 76.0803

Uniform molecular adhesion between a precipitate and a

soluble substance, or between a gas and a metal.

Off Bond 74.0804

A termination that has some portion of the bonding area

extending off the bonding land.

Offset Land 22.0805

A land that is intentionally not in physical contact with its

associated component hole.

IPC-I-001046

Figure N–3 Nonfunctional interfacial connection

Conductor

Non-

functional

Land

▼

IPC-I-001042

Figure N–4 Nonwetting

NONWETTING

SOLDER

BASIS METAL

BASE MATERIAL

IPC-T-50F June 1996

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