The 1 signal layer: the signal layer is mainly used for wire.Protel arranged on the circuit board 99 SE provides 32 signal layers, including Top layer (top), Bottom layer (bottom) and 30 MidLayer (middle layer).
2. Internal power / ground layer: Protel 99 SE provides 16 internal power layer and ground layer. The type of layer is only used for multilayer board, mainly for the arrangement of the power line and ground wire. We call double plate, four layer, 6 layer, generally refers to the signal layer and the internal power supply / ground layer number.
3. Mechanical layer: Protel 99 SE provides 16 mechanical layer, it is generally used to set the outline dimension of the circuit board, marker data, the alignment mark, assembly instructions and other mechanical information. These information due to the requirements of the design company or PCB manufacturer vary. Execution menu life Design|Mechanical layer can for circuit board set more mechanical layer. In addition, mechanical layer can added in other layers together output display.
4. Solder layer: in pad outside the parts coated with a layer of paint, such as anti welding paint, to prevent these parts on the tin. Solder layer on the pad matching in the design process is automatically generated.Protel 99 SE provides top solder (top) and BottomSolder (bottom) two solder layer.
5. Solder mask layer: it and solder mask layer has a similar role, different is in welding machine corresponds to the pasted on the surface of the element of the pad.Protel 99 SE provides top paste (top) and bottom paste (bottom) two solder mask layer.
6 no wiring layer used to define the effective placement of components and wiring on the circuit board area. In the layer draw a closed area as a wiring active area in the region is not automatic layout and wiring.
7. The silk screen layer: silk screen layer is mainly used for placing printed information, such as components of the contour and annotation and commentary characters.Protel 99 SE provides top overlay and bottom overlay two screen layer. In general, each marking character are in the top silkscreen layer, the bottom screen layer can be shut off.
8. Multilayer: circuit board pads and through vias to penetrate the whole circuit board, and different conductive pattern layer to establish electrical connection. Therefore, the system set up a special an abstraction layer, multilayer., pads and vias to arranged in multi-layer, if this layer is off, pads and vias will not be displayed.
9. Drill layer: drill layer provides circuit board manufacturing process of drilling information (such as pad, hole requires drilling) and two bore holes of the multilayer board.Protel 99 SE, top and bottom, middle layer, middle layer and top silkscreen layer, the bottom screen layer.