Dictionary

This is a metallized hole that connects an outer layer to an inner layer(s) in a multi-layer board, without penetrating all the conductive layers.

This is the tool used on CNC equipment to drill the PCB. The diameter of this drill will be determined by the PCB manufacturer, taking into account the drilling tolerance and other characteristics of the project.

Element positioned over one of the areas where the crease will be made and which allows automatic inspection of whether the creases have been made or not.

This is the distance between the tangent of a hole (metallized and/or non-metallized) and the nearest conductor.
d= copper hole

This feature is used to eliminate all traces of screen printing that are too close to or even on the metalized holes and pads of THT and SMD components.

Measuring the capacity (technological limits) of equipment / processes.

Detachment that can occur between prepreg's, UT's and copper in multi-layer boards.

Copper ring surrounding the central circle (fiducial).

Solder mask filament that isolates one pad from another. Very important to prevent shorts

These are metallized holes located on the edge of the plate.

This is a deformation that can occur in the PCB after manufacturing processes.
The image opposite shows a case of warping.
h= warping

These elements are usually found on the copper of the board and serve as a reference for aligning the equipment used in the PCB manufacturing process as well as the assembly process (insertion of electronic components). Their geometric shape can be a circle, square, cross, among others.

It is a material basically composed of fiberglass with epoxy resin. It is the most common laminate used to manufacture printed circuit boards today.

Bed of nails used in the electrical testing of PCBs.

Area of copper located on the inner layer(s) of a multilayer board corresponding to the ground plane or shield of the circuit.

It is the property that certain materials have of absorbing water. These materials include silica gel, copper sulphate, alginate, silicones and wood. Silica and sulphate are used as dehumidifiers in packaging and in environments that require protection against humidity.

High Density Interconnection. An acronym used to define highly dense and critical circuits that require high precision in the manufacture and assembly of components. PCIs with this classification include blind and buried vias, via in pad, extremely small tracks and insulation, fine pitch components and other critical features.

Hot air leveling, also known as HASL - Hot air solder leveling. It is a surface finish commonly used on boards that do not need to comply with the RoHS directive.

This is the distance between two conductors that are not connected to the same Net, be they tracks, pads or ground planes.

This is the resistance to the flow of current in pre-defined tracks in the layout stage of the Printed Circuit Board. These tracks, represented by a combined resistance electrical network, function as transmission lines. In circuits operating at high frequency, the integrity of the signal must be provided by good impedance characteristics of the conductors/rails present on the PCB. The elements shown in the image directly interfere with the desired impedance value.

Laser direct imaging

Nomenclature used mainly in CAM software to refer to the conductive (copper), cosmetic (solder mask and symbology) or drilling/router layer of a PCB.

Mirror direct image

English unit of measurement that corresponds to one millionth of an inch.
Symbol: mil
Equivalence in mm: 1 mil = 0.025

Abbreviation used to indicate "No Plated Thru Hole".

Organic Solderability Preservative - This finish is a surface protection using organic substances. Chemicals react with the copper surface during the process, generating organo-metallic substances that protect the copper surface against oxidation.

Abbreviation used to indicate "Plated Thru Hole".

Material that has been impregnated with a cured resin in a preliminary phase. This material is used as an insulator in the assembly of the multilayer board stackup.

English unit of measurement for length.
Equivalent in mm: 1 inch = 25.4

These are non-metallized holes that allow the panel's PCI or even the false edge to stand out.

English unit of measurement used for length/area.
Symbol: ft (')
Equivalence in mm: 1′ = 12' = 300.50

Elements (pads) present in the inner layers of multi-layer boards that have no connection to other nets.

This is a directive in European Union legislation which states that electronic devices must not contain lead or other harmful substances. In printed circuit boards, the control is carried out on the base laminate and the surface finish is deposited on the solder surfaces.

They correspond to isolations present at points on the same Net.

Surface Mount Device.

These are the inscriptions that are engraved on the surface of the PCB.

Conductor that interconnects the terminals of the components on the printed circuit board.

Through Hole Technology.

Reinforcement at the island/track junction that prevents breakage between connections even with the standard deviations of PCB manufacturing processes.

Mechanical finishing on PCI consisting of cuts on both sides. These cuts are partial because a portion of the material called the crease core is preserved. It is through the core that the board remains attached to the panel and/or false edge.

These are copper pads (without holes) added to areas of the board that do not have a circuit. Their function is to make the copper layer on the surface more homogeneous, so that copper is deposited more evenly inside the holes during the thickening stage.