Two or more polar and non-polar solvents that behave when mixed as a single solvent to remove polar and non-polar contaminants with a boiling point lower than its components.

A lead extending out the end and along the axis of a resistor, capacitor or other axial part rather than from the bottom.

American Wire Gauge. A method of specifying wire diameter; the higher the number, the smaller the diameter.

Hardware that automatically analyses functional or static parameters to evaluate performance degradation. It also performs fault isolation.

Assembling discrete components to PCBs via electrically controlled equipment.

( see Automatic Test Equipment )

A computer language of brief expressions for translation into a machine language.

A manufacturing facility for attaching and soldering components to a printed circuit.

i: A drawing depicting the locations of components, with their reference designators (q.v.), on a printed circuit.

The ratio of the circuit board thickness to the smallest hole diameter.

Acronym for “American Standard Code for Information Interchange”; a seven-bit code that assigns numeric values to letters of the alphabet, the ten decimal digits, punctuation marks and other characters.

An accurately scaled configuration used to produce a master pattern. It is generally prepared at an enlarged scale using various width tapes and special shapes to represent conductors.

An accurately scaled image of the conductive pattern of a PCB which is used to produce the 1:1 production master. The scale is chosen to provide the necessary degree of accuracy.

The resistance of a material to the effects of a high voltage, low-current, under prescribed conditions, passing across the surface of the material. The resistance is stated as a measure of the total elapsed time required to form a conductive path of the surface (material carbonized by the arc).

A water-based method that may include neutralizers, saponifiers, surfactants, dispersants and anti-foaming agents.

Acceptable Quality Level. The maximum number of defectives likely to exist within a population lot that can be considered to be contractually tolerable.

Automatic Optical Inspection.

List containing the shapes and dimensions of pads and tracks, etc., to expose on the film in a photoplotter.

Acronym for “ American National Standards Institute”, an organization formed by industry and the US Government to develop trade and communication standards.

The width of the conductor surrounding a hole through a printed circuit pad.

Text or legend pertinent to a board design; text appears off the board areas and consists of lettering and symbols while legend appears on the boards.

The angle between the face of the squeegee and the surface of the screen.

An extension of a land（like one or two blind paths）on a flexible printed board that extends beneath the cover lay to assist in holding the land to the base material.

A system measuring component values on a populated PCB before power is applied.

At the board level, various analog test signals are applied to a PCB through a switch to point out current outputs.

A tool used to verify the design (or portions thereof) in the analog domain by applying virtual test signals to a virtual model of the design.

The surrounding environment coming into contact with the system or PCB in question.

A circuit comprised primarily of individual (discrete) components, such as resistors, capacitors, diodes, transistors, etc. The circuit output is a continuous electrical signal that varies in frequency, amplitude, etc., as a function of the input. The magnitude is represented by physical variables such as voltages, current, resistance, rotation, etc.

A thermosetting resin with good electrical properties used for moulding the bodies of components.

A procedure for solving a problem, usually mathematical.

The non-conductive air space between current carrying conductors such as traces, pads, ground planes, etc.

The change of a property, e.g. solderability, with time.

A substance such as glue or cement used to fasten objects together. In surface mounting, an epoxy adhesive is used to adhere SMDs to the substrate.

The metal layer that adheres a barrier metal to a metal land on the surface of an integrated circuit.

A process for obtaining conductive patterns by the selective deposition of conductive material on a clad or unclad base material.

A chemical treatment for conditioning the surface of non-conductive materials for improved adhesion.

A thermosetting ,transparent resin.

The deviation of the measured or observed value from the accepted reference.

A series of holes in successive layers. Each set has a common centre or axis. The holes of a multi-layer printed board provide access to the surface of the land in one of the layers of the board.

The maximum number of defects per 100 units that can be considered satisfactory as a process average.

The tests that determine the acceptability of boards as agreed to by purchaser/vendor.