Yield

The ratio of usable parts at the end of a manufacturing process to the number of components submitted for processing.

Wicking

Capillary absorption of liquid along the fibres of the base material.

Whisker

A needle-shaped metallic growth on a printed circuit board.

Wetting

The formation of a relatively uniform, smooth, unbroken and adherent film of solder to a base material.

Weave Exposure

A condition of base material in which a weave pattern of glass cloth is appearing on the surface though the unbroken fibres of the woven cloth are completely covered with resin.

Wave Soldering

The technique of joining parts to a PCB by passing the assembly over a wave of molten solder so as to coat the pre-fluxed areas to be joined.

Wave Exposure

A surface condition of base material in which the unbroken fibres of woven glass cloth are not completely covered by resin.

Voltage Plane

A conductor or portion of a conductor layer on or in a printed board which is maintained at other than ground potential. It can also be used as a common voltage source, for heat sinking, or for shielding.

Void

The absence of any substances in a localized area.

Viscosity

The property of a fluid that enables it to develop and maintain a level of shearing stress dependent upon the velocity of flow and then offer continued resistance to flow. The absolute unit of viscosity measurement is poise, or more commonly, centipoise.

Virtual Prototype

A virtual (computer model) representation of an electronic product that can be used to explore different design scenarios and then verify that the product will work as planned before building a physical implementation.

Via

A plated through-hole used as an interlayer connection and not as a terminating point for a component lead. It may also be blind (incomplete penetration) or buried (non-surfacing).

Via Hole

A plated through-hole whose only purpose is to connect a track on one layer or side of the board through to a track on another layer or side. In a via, there is no intention to insert a component lead or other reinforcing material.

Vapour Phase

The solder re-flow process that uses a vaporized solvent as the source for heating the solder beyond its melting point,creating the component-to-board solder joint.

Vacuum Pick-up

A component handling tool with a small vacuum cup for ease of pick-up and removal during de-soldering.

Unsupported Hold

A hole containing no conductive material nor any other type of reinforcement.

Underwriters’ Symbol

A logotype authorized for placement on a product which has been recognized (accepted) by Underwriters Laboratories, Inc. (UL).

Undercut

A groove or excavation at one edge of a conductor caused by etching.

Ultrasonic Soldering

Fluxless soldering wherein molten solder is vibrated at ultrasonic frequencies while making the joint.

UL

Underwriter’s Laboratories, Inc., a corporation for the purpose of establishing safety standards on types of equipment or components in USA and Canada.

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Ranking Name Answers
1 PCBWay Support 2
2 P****ita 1
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