Activating: A treatment that renders non-conductive material receptive to electroless deposition.
Active Components: Semiconductor devices, such as transistors and diodes, that can change its basic characteristics in an powered electrical circuit, such as amplifiers and rectifiers.
Additive Process: A process for obtaining conductive patterns by the selective deposition of conductive material on clad or unclad-based material.
Analog Circuit: An electrical circuit that provides a continuous quantitative output as a response from its input.
Annular Ring – that portion of conductive material completely surrounding a hole.The copper pad area that remains after a hole is drilled through the pad, measured from edge of hole to edge of pad.
Your inner and outer layer pads should be at least 0.018" larger than the finish hole size (0.010” for vias). If your design has any pad to trace junction minimum requirement, add that to the above numbers [0.018" pad + 0.002" junction should have 0.020" pad]. This will provide a 9mil annular ring for component pins, 5mil annular ring for vias.
Aperture Information:This is a text file describing the size and shape of each element on the PCB printed circuit boards. These are also known as D-code lists. These lists are not necessary if your files are saved as Extended Gerber with embedded Apertures (RS274X).
Array: A group of elements or circuits (or circuit boards) arranged in rows and columns on a base material.
Artwork: An accurately scaled configuration used to produce the artwork master or production master.
Artwork Master: The photographic film or glass plate that embodies the image of the PCB pattern, usually on a 1:1 scale.
Aspect Ratio: The ratio of the length or depth of a hole to its pre-plated diameter (Example. 0.062" thick board 0.0135" drill = aspect ratio of 4.59:1). Maximum aspect ratio allowed for Sunstone Circuits manufacturing is 6:1.
Board Thickness Smallest Drill Size:
0.031" 0.010"
0.042" 0.010"
0.062" 0.010"
0.093" 0.017"
0.125" 0.019"
Designer tip: Minimizing the aspect ratio of the holes improves through hole plating quality and minimizes the chance of via failures.
Assembly: A number of parts, subassemblies, or any combination thereof joined together.
Assembly File: A drawing describing the locations of components on a PCB.
Automated Test Equipment (ATE): Equipment that automatically tests and analyzes functional parameters to evaluate performance of the tested electronic devices.
Backplanes or Backpanels: Complex, multi-layer printed circuit boards used to connect racks of other boards in an electronics rack or enclosure.
Ball Grid Array (BGA): A SMD package in which solder ball interconnects cover the bottom surface of the package.
Bare Board: An un-assembled PCB.
Barrel: The cylinder formed by plating through a drilled hole.
Base Copper: The thin copper foil portion of a copper-clad laminate for PCBs. It can be present on one or both sides of the board.
Base Material: The insulating material upon which a conductive pattern may be formed. It may be rigid or flexible or both. It may be a dielectric or insulated metal sheet.
Base Material Thickness: The thickness of the base material excluding metal foil or material deposited on the surface.
BBT: Bare Board Test.
Bed Of Nails Fixture: A test fixture consisting of a frame and a holder containing a field of spring-loaded pins that make electrical contact with a planar test object (i.e., a PCB).
Bill of materials (BOM): A comprehensive listing of all subassemblies, components, and raw materials that go into a parent assembly, showing the quantity of each required to make the assembly.
Bleeding: A condition in which a plated hole discharges process materials of solutions from voids and crevices.
Blind Via: A conductive surface hole that connects an outer layer with an inner layer of a multi layer board without penetrating the entire board.
Blister: A localized swelling and separation between any of the layers of a laminated base material, or between base material or conductive foil. It is a form of delamination.
Board Thickness: The overall thickness of the base material and all conductive material deposited thereon. The standard base thickness is 1/16 inch (0.062").
Bond Strength: The force per unit area required to separate two adjacent layers of a board by a force perpendicular to the board surface.
Border Area: The region of a base material that is external to that of the end product being fabricated within it.
Bow: The deviation from flatness of a board characterized by a roughly cylindrical or spherical curvature such that if the board is rectangular, its four corners are in the same plane.
B-Stage: An intermediate stage in the reaction of a thermosetting resin in which the material softens when heated and swells, but does not entirely fuse or dissolve, when it is in contact with certain liquids.
B-Stage Material: Sheet material impregnated with a resin cured to an intermediate stage (B-stage resin). PrePreg is the popular term.
B-Stage Resin: A thermosetting resin that is in an intermediate state of cure.
Built In Self Test: An electrical testing method that allows the tested devices to test itself with specific added-on hardware.
Buried Via: A via hole that does not extend to the surface of a printed board.
Burn-In Testings: Burn-In Testing is a thermal test method where products are powered on for extended periods to ensure product functionality.
Burr: A ridge left on the outside copper surface after drilling.
CAD: Computer Aided Design.
CAM: Computer Aided Manufacturing.
CAM Files: The files used for manufacturing PCB including Gerber file, NC Drill file and Assembly Drawings.
Capacitance: The property of a system of conductors and dielectrics which permits storage of electricity when potential difference exists between conductors.
Catalyst: A chemical that is used to initiate the reaction or increase the speed of the reaction between a resin and a curing agent.
Center to Center Spacing: The nominal distance between the centers of adjacent features on any single layer of a printed board, e.g.; gold fingers and surface mounts.
Ceramic Ball Grid Array (CBGA): A ball grid array package with a ceramic substrate.Chamfer: A broken corner to eliminate an otherwise sharp edge.
Check Plots: Pen plots, or plotted film, that are suitable for checking and for design approval by customers.
Chip: The individual circuit or component of a silicon wafer, the leadless form of an electronic component.
Chip Scale Packaging: A method of using integrated circuits (chips) without encapsulating them in epoxy, thereby utilizing less space on the circuit board.
Chip-on-Board (COB): A configuration in which a chip is directly attached to a printed circuit board or substrate by solder or conductive adhesives.
Circuitry Layer: A layer of a printed board containing conductors, including ground and voltage planes.
Clad Or Cladding: A relatively thin layer or sheet of metal foil that is bonded to a laminate core to form the base material for printed circuits.
Clearance Hole: A hole in the conductive pattern that is larger than, and coaxial with a hole in the base material of a printed board.
Clearances: A clearance (or isolation) is a term used to describe the space from a power or ground layer to a plated through hole.
CNC (Computer Numerical Control): A system that utilizes a computer and software as the primary numerical control technique.
Coating: A thin layer of material, conductive, magnetic or dielectric, deposited on a substance surface.
Coefficient of Thermal Expansion (CTE): The ratio of dimensional change of an object to the original dimension when temperature changes, expressed in %/oC or ppm/oC.
Component Hole: A hole used for the attachment and electrical connection of a component termination, including pin or wire to the circuit board.
Component Side: The side of the circuit board on which most of the components are mounted. In order to build your printed circuit board correctly, we must be able to identify the correct orientation of your design. Component, layer 1, or 'top' layer should read in facing up. All other layers should line up as though looking through the board. Please use layer designators, pass through marks, or correct reading layer text.
Conductive Pattern: The configuration pattern or design of the conductive material on a base material. (This includes conductors, lands, vias, heat sinks and passive components when those are integral parts of the printed board manufacturing process.
Conductor: A thin conductive area on a PCB surface or internal layer usually composed of lands (to which component leads are connected) and paths (traces).
Conductor Spacing: The distance between adjacent edges (not centerline to centerline) of isolated conductive patterns in a conductor layer.
Conductor Thickness: The thickness of the conductor including all metallic coatings.
Conformal Coating: An insulating protective coating which conforms to the configuration of the object coated and is applied on the completed board assembly.
Connectivity: The intelligence inherent in PCB CAD software which maintains the correct connections between pins of components as defined by the schematic.
Connector: A plug or receptacle which can be easily joined to or separated from its mate. Multiple-contact connectors join two or more conductors with others in one mechanical assembly.
Connector Area: The portion of the circuit board that is used for providing electrical connections.
Contact Angle (Wetting Angle): The angle between the contact surfaces of two objects when bonding. The contact angle is determined by the physical and chemical properties of these two materials.
Continuity: An uninterrupted path for the flow of electrical current in a circuit.
Continuous outline: The outline or cut line for the printed circuit board made from a single continuous line. This line may not contain any broken/overlapping lines and/or improperly drawn arcs. The outline describes the shape of the board and is required for creating the route program.
Controlled Impedance: The matching of substrate material properties with trace dimensions and locations to create specific electric impedance as seen by a signal on the trace.
Characteristic impedance extends the concept of resistance to AC circuits, describing not only the relative amplitudes of the voltage and current, but also the relative phases. When the circuit is driven with direct current (DC) there is no distinction between impedance and resistance; the latter can be thought of as impedance with zero phase angle.
Copper Foil (Base Copper Weight): Coated copper layer on the board. It can either be characterized by weight or thickness of the coated copper layer. For instance, 0.5, 1 and 2 ounces per square foot are equivalent to 18, 35 and 70 um-thick copper layers.
Core Thickness: The thickness of the laminate base without copper.
Corrosive Flux: A flux that contains corrosive chemicals such as halides, amines, inorganic or organic acids that can cause oxidation of copper or tin conductors.
Crosshatching: The breaking up of large conductive area by the use of a pattern of voids in the conductive material.
C-Stage: The condition of a resin polymer when it is in a solid state with high molecular weight. Being insoluble and infusion.
C-Stage Resin: A resin in its final state of cure.
CTE- (Coefficient of Thermal Expansion): Coefficient of thermal expansion. The measure of the amount a material changes in any axis per degree of temperature change.
CTI - (Comparative Tracking Index): It indicates the highest usable voltage for a laminate. It becomes important in application with high humidity, such as washing machines or cars. A higher index means a better protection. Similar is 'PTI' and 'KC'
Curing: The irreversible process of polymerizing a thermosetting epoxy in a temperature-time profile.
Curing Time: The time needed to complete curing of an epoxy at a certain temperature.
Cut line: The cut line will be used to program the router path and it represents the circuit board outside edge. The tolerance on route dimension is +/- 0.010". It is recommended to keep outer layer copper 0.010” and inner copper 0.020” from the cut line to avoid exposing copper at the board edge.