PCB Glossary

Printed Circuit Boards


PCB, printed circuit board is a thin board made of fiberglass, composite epoxy, or other laminate material.

Multilayer PCB

A Multi-Layer PCB is a PCB that has more than two layers.


FR4 is a sign for rating flame resistant material. It specifies that resin material is capable of automatically extinguishing when it is in a flame state.


HDI, a short form for high density interconnector, is a type of technology for PCB fabrication. It depends on micro blind via technology to manufacture PCBs with traces organized with high density.

Gold fingers

Gold fingers are connectors on the edge of a PCB after gold plating. They have to be hard, smooth, and flat, behave excellently as a conductor

External layer

External layer of PCB, also called outer layer, is an outer copper layer where components are attached to.


Cutout refers to a groove that is dug on a PCB.

Chip-on-board (COB)

Chip on board is a type of bare chip SMT technology by directly mounting chip on a PCB.

PCB house

PCB house is the factory fabricates PCB.