02/23/2024
PCB GLOSSARY
Analog Circuit: An electrical circuit that provides a continuous quantitative output as a response from its input.
Array: Combining multiple individual PCBs into a subpanel to facilitate the assembly process.
ASCII: American Standard Code for Information Interchange. ASCII is the basis of character sets used in almost all present-day computers.
Assembly: The process of positioning and soldering components to a PCB. The act or process of fitting together parts to make a whole.
Assembly Drawing: A drawing depicting the locations of components with their reference designators on a printed circuit. Also called "component locator drawing."
Automated Test Equipment (ATE): Equipment that automatically tests and analyzes functional parameters to evaluate performance of the tested elec¬tronic devices.
Blind Vias: Used in multilayer boards where a drilled hole requires connections from an outer layer to an inner layer, when the hole must not go through the entire PCB.
Buried Vias: Used in multilayer boards where inner layers require connections between a subassembly of layers, but the via does not extend to the outer layers.
Copper Weight: The thickness of copper on the surface of a PCB layer. It is measured in oz./sq. ft. For example, 1 oz. = a nominal thickness of 0.00014”.
Design for Manufacturing (DFM): Ensures that the design fits the fabrication process requirements. DFM includes assessments for minimal trace width, minimal trace-to-trace distance, minimal hole size, and minimal hole clearance in context with industry established guidelines for limits of producibility.
Dielectric: An insulating medium between conductors or conductive layers.
Etch Compensation: Small adjustments to nominal customer-provided Ge**er data that compensate for the amount of copper that will be etched from the traces and pads. This will vary depending on the copper weight but will be trans¬parent to the final PCB.
Ge**er File: Data file used to control a laser-imaging machine, such as a photo¬plotter.
Ground Plane: A conductive plane as a common ground reference in a multi¬layer board for current returns of the circuit elements and shielding.31
Impedance: The measure of the opposition (resistance) that a circuit presents to the passage of a current when a voltage is applied in an alternating current circuit. Controlled impedance is the process of manufacturing a PCB to meet a specific impedance requirement.
Land: Metallized area of the board for connection and attachment of electronic components.
Legend (Silk Screen): A layer designated to place legend elements on the top or bottom side of the board. Two corresponding layers are available—the top and bottom silk.
Minimum Conductor Width: The smallest width of any conductors, such as traces, on a board.
Minimum Conductor Space: The smallest distance between any two adjacent conductors, such as traces, on a board.
Net: A set of connection points that are to be connected electrically on the board.
Netlist: A list of parts and their connection points that are connected in each net of a circuit.
Pick-and-Place (Automatic Component Placement): Machines used to auto¬mate component placement. High-speed component placement machines, known as chip shooters, place the smaller, lower pin count components. More complex components with higher pin counts are placed by fine pitch machines that have greater precision.
Plated Through-Hole (PTH): A plated hole used as a conducting interconnec¬tion between different layers or sides of a board. Serves as a connection for through-hole components or vias.
Signal Layer: Layer of a board in which traces can be placed. For a two-sided board, two signal layers are available—the top and the bottom layers.
Test Point: A specific point on a PCB used for specific testing of functional adjustment or quality in the circuit-based device.
Through-Hole: A drilled hole in the board, usually used for mounting purposes.
Via: A plated through-hole used for the interconnection of
