Through-Hole Technology (THT)

Through-hole assembly, known as Through-Hole Technology (THT), is a method of mounting electronic components on a printed circuit board. In this process, the lead wires or pins of the components are passed through holes provided for this purpose in the printed circuit board and soldered on the opposite side.

Through-hole assembly is used, amongst other things, for components where the connection must be able to withstand high mechanical stress. Larger components or those which, due to their design, are not suitable for surface-mount assembly alone can also be manufactured using the THT method.

In contrast, with SMD technology, the components are mounted directly onto the surface of the printed circuit board. Both mounting methods can also be used together on a single printed circuit board.

LEDs are also available as leaded components for through-hole mounting. See wired LED for further details.