Dome

In membrane switch technology, a hemispherical tactile element used to provide tactile or audio feedback.

Doping

The process and its (doping) elements, usually a trivalent element for p-type semiconductors; or, a pentavalent element for n-type semiconductors. The doping process uses one of the latter elements to lightly adulterate in composition the intrinsic semiconductors of either pure silicon or germanium, respectively, converting them into extrinsic semiconductors.

See also Semiconductor Material.

Dot Coding

Process of tool imprinting a 22-10 AWG PIDG or PG terminal. Dot coding indicates whether the proper tool has been used.

Double-Grip Terminal

Solderless terminal with a metal sleeve added to the barrel to provide an area for a double crimp. In a double crimp, one crimp is over the wire and a second over the insulation. This provides additional strain relief and is ideal when vibration is a problem.

See also Crimp.

Double-Pole

A contact arrangement of two separate contact combinations.

Double-Pole Switch

Switch that opens or closes two independent circuits with a single actuating device.

Double-sided Assembly

A packaging and interconnecting structure with components mounted on both the primary and secondary side.

Double-Throw Switch

Switch in which the moving contact closes a circuit at one of its extreme positions while opening a circuit at the other.

Downsizing

In general, moving applications from larger to smaller equipment. A specific example would be removing applications from hosts and replacing them with client/server applications that work over LANs.

Downtime

The time when the equipment is involuntarily not running. E.G. stoppages due machine repair, no material, no labor, no setup, etc. However, it excludes stoppages due to no orders which are termed as excess capacity.

DPDT

Double Pole, Double Throw switch

DPST

Double Pole, Single Throw switch

Drag Soldering

Process in which supported, moving assemblies are brought in contact with the surface of a static pool of molten solder.

Drain Conductor

A conductor in continuous contact with a shield for ground termination or draining ground current.

Drain Wire

  1. In a cable, the non-insulated wire laid over the component or components and used as a ground termination.
  2. A non-insulated wire in contact with a shield throughout its length, and used for terminating the shield (draining the ground current).

DRAM

Dynamic Random Access Memory. A type of random access memory (RAM) that uses metal-oxide semiconductors. It is made up of a large number of bit cells that temporarily hold information and have to be continuously refreshed (renewed) about every two microseconds.

Draw-Quality Steel

Some components are blanked or stamped into shape. Others are drawn, or slowly formed and pushed into shape. The drawing process requires a higher quality steel, which is called draw-quality.

Drop

A single cable running between wiring closets or from the closet to a work area.

Drop Cable

  1. Also known as a transceiver cable. The cable that connects individual PCs or other nodes to a bus on a LAN.
  2. The coaxial cable that connects the feeder portion of the distribution system to the subscriber's premises.

Dross

Oxide and other contaminants which form on the surface of molten solder (or other molten metals).

Dry Circuit

A circuit in which current and voltage are so low that there is no arcing to roughen the contacts. A dry circuit can develop an insulating film that prevents circuit closing when contacts are brought together.

Dryer

A device for drying molded plastic.

Plastic housing material absorbs moisture, which degrades quality. Material must therefore be dried, usually for 4-6 hours at specified temperatures. Standard nylon 6/6 absorbs the most moisture; polyester absorbs much less. Drying requirements vary accordingly. The process can use a large central dryer for a group of machines or one small dryer mounted on each machine.

DS

Digital Signal

DSEC

Double Sided Edge Connector

See Edge Connector.

Dual Beam

A type of stamped-and-formed contact where the female contact holds the male contact between two beams. Also called a bifurcated design.

Dual In-line Memory Module

See DIMM.

Dual In-line Package (DIP)

A common package-to-board connector with 6 to 64 contacts arranged along two sides. DIP sockets are used where board space is not critical.

Dual Readout

A term used to describe card-edge connectors used with double-sided PC boards.

Duct

A single, enclosed raceway for wires or cables.

Dummy Connector Assembly

Two or more dummy connectors that have a common mounting or are mounted on each other, each one capable of being independently replaced. Excludes items which are furnished as mated pairs or sets.

Dummy Connector, Plug

An item specifically designed to mate with another connector to perform one or more special functions.

Dummying

The process of removing metallic impurities from a plating solution with a large area dummy cathode.

Duplex

A duplex cable contains two fibers; a duplex connector links two pairs of fibers.

Duplex Plating

A plating process similar to selective gold plating, in which only the contact area is gold plated.

DVI

Digital Video Interface

DVM

Digital Volt Meter

Dyeing

Some customers require parts to be in color. Premium line can either use colored raw material to mold (if demand is high) or mold natural color and dye it in a separate process after molding.

Dynamic Gap

The minimum distance between opposing contacts in a connector when a PC board is removed rapidly.