Let's continue to introduce another part of the terms of PCB SMT.
The terms and definitions we have introduced primarily follow the IPC-T-50. Definitions marked with an asterisk (*) are sourced from the IPC-T-50.
1. Intrusive Soldering: Also known as paste-in-hole, pin-in-hole, or pin-in-paste processes for through-hole components, this is a type of soldering where the component leads are inserted into the paste before reflow.
2. Modification: The process of altering the size and shape of the apertures.
3. Overprinting: A stencil with apertures that are larger than the corresponding pads or rings on the PCB.
4. Pad: The metallized surface on a PCB used for the electrical connection and physical attachment of surface-mount components.
5. Squeegee: A rubber or metal blade that effectively rolls the solder paste across the stencil surface and fills the apertures. Typically, the blade is mounted on the printer head and is angled so that the printing edge of the blade falls behind the printer head and the forward face of the squeegee during the printing process.
6. Standard BGA: A Ball Grid Array with a ball pitch of 1mm [39mil] or larger.
7. Stencil: A tool composed of a frame, mesh, and a thin sheet with numerous apertures through which solder paste, adhesive, or other mediums are transferred onto a PCB.
8. Step Stencil: A stencil with apertures of more than one level thickness.
9. Surface-Mount Technology (SMT)*: A circuit assembly technology where the electrical connections of components are made through conductive pads on the surface.
10. Through-Hole Technology (THT)*: A circuit assembly technology where the electrical connections of components are made through conductive through-holes.
11. Ultra-Fine Pitch Technology: Surface mount technology where the center-to-center distance between component solder terminals is ≤0.40 mm [15.7 mil].
In the next article, we will learn about the materials of SMT Stencil.
