The meaning of each layer of the PCB circuit board
1. Signal layer: signal layer is mainly used to arrange the wires on the circuit board.Protel 99 SE provides 32 signal layers, including Top layer(Top layer),Bottom layer(Bottom layer) and 30 MidLayer(middle layer).
2. Internal power/connection layer: Protel 99 SE provides 16 internal power layers/connection layers. This type of layer is only used for multi-layer plates and is mainly used for laying power lines and grounding wires.
3. Mechanical Layer: Protel 99 SE Layer provides 16 machinery, it usually is used to set the appearance of the circuit board size, data tags, alignment, assembly instructions, and other Mechanical information. This information for their Design company, or the requirements of the PCB manufacturer is different. The execution menu command Design | Mechanical Layer for circuit board more Mechanical Layer Settings. In addition, the machine can be attached to the other layers on output shows together.
4. Welding resistance layer: coating all parts outside the welding plate with a layer of paint, such as anti-welding paint, to prevent tin from these parts. The welding resistance layer is automatically generated when matching the welding plate in the design process.Protel 99 SE provides Top Solder(Top layer) and BottomSolder(bottom layer).
5. Solder Paste protection layer: it is similar to the soldering resistance layer, except the welding disk of the corresponding surface pasted element when the machine is welded.Protel 99 SE provides two solder Paste protection layers of Top Paste(Top layer) and Bottom Paste(Bottom layer).
6. No wiring layer: used to define areas where components and wiring can be effectively placed on the circuit board. In this layer, a closed area is drawn as the wiring effective area, which cannot be automatically arranged and wired outside the area.
7. Screen printing layer: the screen printing layer is mainly used to place printing information, such as the outline and marking of components, various annotation characters, etc.Protel 99 SE provides two screen printing layers, Top Overlay and Bottom Overlay.
8. Multilayer: the soldering disc and penetrating hole on the circuit board shall penetrate the whole circuit board and establish electrical connection relations with different conductive graphic layers. Therefore, the system is specially equipped with an abstract layer and multilayer.
9. Drilling layer: the drilling layer provides drilling information in the manufacturing process of the circuit board (for example, in the process of welding disc, drilling is required after passing through the hole).Protel 99 SE provides and two drilling layer multi-layer boards, top and bottom layers, middle layers, middle layers, top layer silk screen printing layer and bottom layer silk screen printing layer.