Overview

Plated-Through-Holes (PTH) in printed circuit boards (PCB) may have predated most Surface-Mount-Technologies (SMT), but the same issues that were a concern then are a concern now.
Rush PCB understands the issue of working with all aspects of PTH technology: design, fabrication, and assembly.

PCB Design

The reliability of PTH starts with the design process, making sure the PCB is designed for manufacturability.

PCB Fabrication

A PCB with Plated-Through-Holes is like a PCB fabricated for Surface-Mount-Technology, with a few more steps in the manufacturing process.
After most of the PCB is fabricated, copper foil is laminated to both sides of the PCB. Holes are then drilled through the circuit board, and the insides of the holes are electro-plated, using the foil on the outside to help with the plating process. The outside copper is then etched to form normal traces and pads.

PCB Assembly

Plated-Through-Hole assembly requires wave soldering to completely apply the solder from the bottom to the top the hole, and onto the pad.
When assembling the PCB and components, care should be taken:
• If lead free solder is used, tighter temperature settings are needed to avoid damage; the solder, being lead free, has a higher melting temperature, if the process is set wrong there is a greater likelihood to damage the components, especially when wave soldering.
• Removing the solder from inside the hole during rework has more potential to damage the joint connecting the annular rings to the hole plating.

Rush PCB is familiar with all aspects of Plated-Through-Hole technology. Call or email us at sales@rushpcb.co.uk to let us help you with all your questions and concerns with PTH.