Wire-to-board connectors are used to interconnect printed circuit boards (PCBs) by using connectors attached to wires.
Specifications for a wire to board connector include the following.
Wire-entry angle - There are three wire-entry angle styles: vertical, right-angle, and bottom-entry.
Wire size - Wire size is usually measured in American wire gauge (AWG), a standard for non-ferrous wire conductor sizes. The term "gauge" refers to the wire’s diameter. The higher the gauge number, the smaller the diameter and the thinner the wire.
Circuits or positions - With wire to board connectors, the number of circuits or positions may range from 1 to 120.
Pitch or center spacing - Pitch or center spacing is measured in millimeters (mm) or inches.
Lock to mating style - There are three basic lock-to-mating styles: positive, friction, and friction ramp.
Maximum current - The maximum current or current-carrying capacity is measured in amperes (A) and ranges from 1.0 A to 50. A.
Crimp is the physical compression of a contact wire around a conductor to make an electrical and mechanical connection. Insulation displacement connectors (IDC) slice through the cable insulation to make a connection. Choices for termination method also include cage clamp, screw, tabs, and solder cups.
PCB Mounting Styles
With wire to board connectors, there are four choices for PCB mounting.
Through-hole technology (THT) mounts components on a PCB by inserting component leads through holes in the board and then soldering the leads in place on the opposite side of the board.
Surface mount technology (SMT) adds components to a PCB by soldering component leads or terminals to the top surface of the board. SMT components have a flat surface that is soldered to a flat pad on the face of the PCB. Typically, the PCB pad is coated with a paste-like formulation of solder and flux.
Press-fit and compression-style board to board connectors are also commonly available.
Wire-to-board connectors carry approvals from various national and international organizations. In North America, they often bear marks from Underwriters Laboratories (UL) and/or the Canadian Standards Association (CSA).
A wire to board connector for the European marketplace should comply with the Restriction of Hazardous Substances (RoHS) and Waste Electrical and Electronic Equipment (WEEE) directives from the European Union (EU). Wire-to-board connectors that comply with other requirements are also available.
BS 9526 N0001 - Specification for multi-contact edge socket electrical connectors