Monday, November 11, 2013
PCB Layer Definition
For the base skills for PCB board engineer is to know the PCB terms, especially for each layer, each hole, each unit, etc. In the EDA software terminology, there are a lot of terms is not have the same definition. The following could explain the different in literally meaning, which may help the unprofessional person to better understanding and learning the necessary terms.
Mechnical: generally refers to the type plate machining dimension layer
Keep out layer: definition cannot go line, perforation (via) or parts area. These limits can separate definitions.
Top overlay: can't literally know its meaning. To provide more information to further discussion.
Bottom overlay: can't literally know its meaning. Can provide more information for further discussion.
Exposed Top paste: top need copper on a part of the solder paste.
Bottom paste: need to show on the copper solder paste at the bottom of the part.
Top solder: shall mean the top resistance welding layer, to avoid in the process of manufacturing or in the future maintenance may not be short circuit
Bottom solder:Should refer to the underlying resistance welding layer.
Drill guide: it could be different aperture size, the corresponding symbol, and the number of a table.
Drill drawing: refers to the hole of the bitmap, different aperture will have a corresponding symbol.
Multilayer: there should be no separate this layer, can refer to a Multilayer, in view of the single panel and double panel.
Top paste: namely the surface patch when open stencil to use.
Bottom paste: that is the underlying patch when open stencil to use