1.Signal layer
The signal layer is mainly used to lay out 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 plane layer (internal power/ground layer)
Protel 99 SE provides 16 internal power/ground layers. This type of layer is only used for multi-layer boards and is mainly used to lay out power lines and ground lines. We call it double-layer board, four-layer board, six-layer board, generally Refers to the number of signal layers and internal power/ground layers.
3.Mechanical layer
Protel 99 SE provides 16 mechanical layers, which are generally used to set the circuit board's overall dimensions, data marks, alignment marks, assembly instructions and other mechanical information. This information varies depending on the requirements of the design company or PCB manufacturer .Execute the menu command Design|Mechanical Layer to set more mechanical layers for the circuit board. In addition, the mechanical layer can be attached to other layers and output and displayed together.
4.Solder mask layer
Apply a layer of paint, such as solder mask, to various parts other than the solder pads to prevent tin from being applied to these parts. The solder mask is used to match the solder pads during the design process and is automatically generated. Protel 99 SE provides Top There are two solder resist layers: Solder (top layer) and Bottom Solder (bottom layer).
5.Paste mask layer (solder paste protective layer)
It has a similar function to the solder mask, except that it corresponds to the pads of surface-mounted components during machine soldering. Protel 99 SE provides two solder paste protective layers: Top Paste (top layer) and Bottom Paste (bottom layer).
6.Keep out layer (disable wiring layer)
It is used to define the area where components and wiring can be effectively placed on the circuit board. Draw a closed area on this layer as the effective wiring area. Automatic layout and wiring cannot be performed outside this area.
7.Silkscreen layer
The silk screen layer is mainly used to place printed information, such as component outlines and annotations, various annotation characters, etc. Protel 99 SE provides two silk screen layers, Top Overlay and Bottom Overlay. Generally, various annotation characters are on the top silk screen layer. The bottom silk screen layer can be closed.
8.Multi layer
The pads and through-holes on the circuit board need to penetrate the entire circuit board and establish electrical connections with different conductive pattern layers. Therefore, the system specially sets up an abstract layer, multi-layer. Generally, the pads and vias are both To be set on multiple layers, if this layer is turned off, the pads and vias cannot be displayed.
9.Drill layer
The drilling layer provides drilling information during the circuit board manufacturing process (such as pads and vias that need to be drilled). Protel 99 SE provides two drill grids (drilling instructions) and Drill drawing (drilling diagrams). hole layer.
Correspondingly, there are many layers in eagle (commonly used ones are marked in green)
In Layout and Package Editor
1 Top Tracks, top side
2 Route2 Inner layer (signal or supply)
3 Route3 Inner layer (signal or supply)
4 Route4 Inner layer (signal or supply)
5 Route5 Inner layer (signal or supply)
6 Route6 Inner layer (signal or supply)
7 Route7 Inner layer (signal or supply)
8 Route8 Inner layer (signal or supply)
9 Route9 Inner layer (signal or supply)
10 Route10 Inner layer (signal or supply)
11 Route11 Inner layer (signal or supply)
12 Route12 Inner layer (signal or supply)
13 Route13 Inner layer (signal or supply)
14 Route14 Inner layer (signal or supply)
15 Route15 Inner layer (signal or supply)
16 Bottom Tracks, bottom side
17 Pads Pads (through-hole) component pins (through-hole type, patch pins are counted on the top and bottom layers)
18 Vias Vias (through all layers)vias
19 Unrouted Airlines (rubber bands)
20 Dimension Board outlines (circles for holes) *)Board outline, equivalent to mechanical layer
21 tPlace Silk screen, top side silk screen layer
22 bPlace Silk screen, bottom side silk screen layer
23 tOrigins Origins, top side (generated autom.) There is a cross in the middle of the component, which represents the position of the component.
24 bOrigins Origins, bottom side (generated autom.)
25 tNames Service print, top side (component NAME)
26 bNames Service print, bottom s. (component NAME)
27 tValues Component VALUE, top side
28 bValues Component VALUE, bottom side
21~28 can be placed entirely on the silk screen layer during plate making.
29 tStop Solder stop mask, top side (gen. autom.)
30 bStop Solder stop mask, bottom side (gen. Autom.)
31 tCream Solder cream, top side
32 bCream Solder cream, bottom side
33 tFinish Finish, top side
34 bFinish Finish, bottom side
35 tGlue Glue mask, top side
36 bGlue Glue mask, bottom side
37 tTest Test and adjustment information, top side
38 bTest Test and adjustment inf., bottom side
39 tKeepout Restricted areas for components, top side
40 bKeepout Restricted areas for components, bottom s.
41 tRestrict Restricted areas for copper, top side
42 bRestrict Restricted areas for copper, bottom side
43 vRestrict Restricted areas for vias
44 Drills Conducting through-holes
45 Holes Non-conducting holes
46 Milling Milling
47 Measures Measures
48 Documentation
49 Reference Reference marks
51 tDocu Detailed top screen print
52 bDocu Detailed bottom screen print
