NPTH

NPTH refers to Non-Plated Through Hole. In printed circuit board (PCB) manufacturing, a through hole is a hole that passes through one or more layers of the PCB. These holes are typically plated with copper to create an electrical connection between layers. A non-plated through hole, on the other hand, is a hole that passes through one or more layers but does not have a conductive plating.

NPTHs serve various purposes in PCB design. They are commonly used for mounting components that do not require electrical connection, such as screws, standoffs, or connectors that use mechanical fastening. They can also be used as alignment holes for automated assembly processes or for testing probes. In some cases, NPTHs are used as vias to provide a passage for routing traces on different layers without establishing an electrical connection.

The manufacturing process for NPTHs differs from plated through holes. After the PCB substrate is drilled, the holes designated as NPTH are not subjected to the electroless copper plating process. This distinction is crucial as it ensures that these holes remain non-conductive. The size and placement of NPTHs are critical design considerations, impacting mechanical integrity and assembly efficiency. Designers specify NPTHs in their PCB layout files, which are then used by the fabrication house to produce the boards accurately.