1.ENIG board: refers to the PCB where the Eing processing craft is used for the welding pad.
2.Top and bottom: The top surface is packaged with a larger number or more complex components. Packaging and Interconnecting Structure, corresponding to the top surface of the EDA software, corresponding to the second mounting surface of the solder; bottom surface, Interconnected structure with the top corresponds to the bottom face of the EDA software, corresponding to the first assembly surface of the weld.
3.Heat sink welding pad: refers to the pad used for component heat dissipation in the middle of the component pad pattern. Generally, there is a metallized heat conduction hole.
4.Stencil Windows: refers to the window through which the solder paste is printed on the steel mesh.
5. Plug hole, open small window and open large window: plug hole, refers to the solder mask of the solder mask covering the via hole (Via Hole), requires no copper or void in the hole; open small window, resistance welding craft in which the soldering material only covers the lead hole part of the solder plate; the large window refers to the solder resist craft in which the solder resist material does not cover the via pad.
6. Solder Beading: refers to a solder ball that is attached to a component body and has a large size.
7. Solder Ball: A solder ball that is distributed around the pad and has a small size.
8.CTE: Abbreviation for Coeficent of Thermal Expansion, is coefficient of thermal expansion.
9. Tg: glass phase transition temperature.
10.Lead-free craft: refers to the welding craft using lead-free solder. Products must comply with RoHS requirements. In addition to solder, all materials such as components and PCBs must comply with RoHS requirements.
11.Mixed craft: Generally refers to the craft of soldering lead-free components with lead solder paste. In most cases, it refers to the craft of soldering lead-free BGA with lead solder paste. Lead-free solder paste soldered lead components are also a mixed craft, but because it does not meet RoHS requirements, this craft is generally not used.
12 Pitch & Spacing: Pitch refers to the distance between the centerlines of the pins; spacing refers to the spatial distance between the two pins.
13. Skew & Offset: Skew refers to the deflection of the component relative to the welding pad; displacement refers to the positional offset of the component relative to the welding pad.
14. Lead & Termination: The pin generally refers to the lead wire of the plug-in and the chip component; the termination end refers to the soldering surface of the leadless chip component.