A PTH, plated through-hole, is drilled through the full stack after lamination, made conductive with electroless copper or direct metallisation, then electroplated so a continuous copper barrel, typically 20 to 25 micrometres thick on average, joins every layer it touches. PTHs serve both as through vias and as holes for through-hole component leads. The counterpart NPTH, non-plated through-hole, is used for mounting screws and tooling and is drilled separately or masked from plating.
Barrel cracks on the PTHs after thermal cycling, the plating's only 15 microns, that's under Class 2.
Also heard as
- plated through-hole
- plated through hole
- plated hole
Do not mix it up with
- Through-hole: Through-hole is the component mounting technology; PTH names the plated hole itself, which may hold a lead or act as a via.
Related terms
Via
Plated hole that connects copper on one layer of a board to copper on another.
Plating
Electrochemical deposition of copper or other metals on a board, building hole walls and surface conductors.
Aspect ratio
Ratio of a board's thickness to the diameter of a drilled hole, which limits how well the hole can be plated.
Through-hole
Mounting method where component leads pass through plated holes and are soldered on the far side.