The property of a dielectric which determines the electrostatic energy stored per unite volume for a potential gradient.
DieThe uncased and normally leadless form of an electronic component that is either active or passive, discrete or integrated.
DurometerA measurement of the hardness of a non-metal such as rubber, plastic, etc. Also the instrument for such measurement.
Dummy_ComponentA mechanical package without the die, used to verify placement processes.
Dual_Solder_WaveIn wave soldering, the first wave’s multi-directional jet leaves solder on all contacted surfaces, followed by the second (flat) wave, which effects a finishing appearance by removing bridges and icicles. Intended for surface mount soldering.
Drying_TimeWithin the re-flow process after pre-heat and before peak re-flow temperature wherein volatile materials escape from the solder paste.
Dry_Film_ResistsCoating material in the form of laminated photo-sensitive foils specifically designed for use in the manufacture of printed circuit boards and chemically machined parts. They are resistant to various electroplating and etching processes.
DrossOxide and other contaminates which form on the surface of molten solder.
DrillsSolid, carbide cutting tools designed specifically for the fast removal of material in extremely abrasive, glass-epoxy materials.
DRCDesign Rule Check: Checks the integrity of print (PCB) so that problems like short-circuits, unrouted nets, etc. are recognized.
Drag_outA measure of cleaning solution lost via board emergence after immersion.
Drag_SolderingThe making of soldered terminations by dipping the colder side of a supported printed board with through-hole mounted components into the surface of a static pool of molten solder and moving it horizontal in one direction.
DPFDisc Plot Format.
Double_sided_BoardA printed board with a conductive pattern on both sides.
Double_sided_AssemblyA PCB with components mounted on both skies.
DocumentationInformation on an assembly that explains the basic design concept, type and quantity of parts and materials, special manufacturing instruction, and up-to-date revisions.
Disturbed_Solder_ConnectionA solder connection that is characterized by the appearance that there was motion between the metals being joined when the solder was solidifying (not accepted).
DispersentA chemical added to the cleaning solution to improve its particulate-removal ability.
Discrete_ComponentA component which has been fabricated prior to its installation (i.e., resistors, capacitors, diodes, transistors, capacitors, diodes, transistors, etc ). A single function component.
DIP_SolderingA process whereby printed boards are brought into contact with the surface of a static pool of molten solder for the purpose of soldering the entire exposed conductive pattern in one operation.
Dimensional_StabilityA measure of dimensional change cause by such factory as temperature, humidity, chemical treatment, age, or stress (usually expressed as units/unit).
Dimensional_HoleA hole in a printed board where the means of determining location is by co-ordinate values not necessarily coinciding with the stated grid.
DigitizingAny method of reducing feature locations on a flat plane to digital representation of X-Y co-ordinates.
Digital_Logic_SimulatorA tool used to verity the design (or portions thereof) in the digital domain by applying virtual test signals to a virtual model of the design.
Digital_CircuitA circuit comprised mostly of integrated circuits and operate, like a switch (i.e., it is either “ON” or “OFF”).
DielectricAn insulating medium which occupies the region between the conductors. It is also the distance between bonded inner layer conductors.
Dielectric_StrengthThe maximum voltage that a dielectric material can withstand, under specified conditions, without rupturing (usually expressed as volts/units thickness.)
DiceTwo or more dies.
DFSMDry Film Solder Mask.
DezincificationKind of galvanic corrosion, generally associated with two-phase brass alloys, in which the zinc-rich beta phase is selectively leached out of the brass. It occurs when brazed joints are exposed to salt or seawater.
De_wetting:A solder coating that has receded, leaving irregular deposits and indicating that the base metal has not been adequately de-oxidized.
DeviceAn individual electrical element, usually in an independent body, which cannot be further reduced without destroying its stated function.
Design_Width_of_ConductorThe width of a conductor as delineated or noted on the master drawing. (See also: Conductor Base Width and Conductor Width).
DendriteMetallic filaments growing between pads and traces resulting from electromigration.
De_laminationA separation between any of the layers of a base material or between the laminate and the conductive foil, or both.
De_buggingThe process of locating and fixing problems (bugs) in the hardware and software portions of an electronic system.
DatumA defined point, line, or plane used to locate the pattern of layer for manufacturing or inspection, or for both purposes.
DatabaseA collection of inter-related data items stored together without redundancy to serve one or more applications.