Soldering resistance refers to the part of the board to be painted with green oil; Because it is a negative output, there is actually a solder joint.

Part of the actual effect of the mask is not green oil, but tin plating, which is silvery white!

Welding auxiliary layer paste

The mask used for machine chip mounting corresponds to the pads of all chip mounting components. The size of the mask is the same as that of the top floor, and it is used to open the steel mesh and leak tin.

It can be understood as follows:

1, solder resist means to open a window on the whole solder resist green oil in order to allow welding!

2. By default, the area without solder mask should be painted with green oil!

3. Paste

Mask layer is used for patch packaging! SMT packaging: Topplayer layer, topsolder layer, toppaste layer, TopPlayer is as big as toppaste, and topsolder is bigger than them. DIP package only uses: topsolder and multi-layer (after some decomposition, I found that multi-layer is actually toplayer, bottomlayer, topsolder, bottom layer size overlap), and topsolder/bottomlayer is larger than Top toplayer/bottomlayer.

The mechanical layer defines the appearance of the whole PCB. In fact, the mechanical layer we are talking about refers to the external structure of the whole PCB. The forbidden wiring layer is the boundary that we define when laying copper with electrical characteristics. That is to say, after we define the forbidden wiring layer first, it is impossible for us to lay wires with electrical characteristics outside the boundary of the forbidden wiring layer in the later laying process.

Topoverlay and bottomoverlay are screen-printed characters that define the top and bottom, that is, component numbers and some characters that we usually see on PCB boards.

Toppaste and bottompaste are the upper and lower pad layers respectively, which means that we can see the exposed copper and platinum (for example, we draw a line on the top wiring layer, and what we see on the PCB is only a line covered by the whole green oil, but we draw a square or a point on the toppaste layer at the position of this line, and the square and this point on the printed board have no green oil, but copper and platinum.

top

Solder and bottomsolder are just the opposite of the first two layers. It can be said that these two layers should be painted with green oil, and the multi-layer is actually similar to the mechanical layer. As the name implies, this layer refers to all layers of PCB.

1 signal layer (signal layer)

The signal layer is mainly used to arrange the wires on the circuit board. Protel 99 SE provides 32 signal layers, including top layer and bottom layer.

Layer (bottom layer) and middle layer (middle layer) in 30.

2 Internal plane layer (internal power/ground layer)

Protel 99

SE provides 16 internal power/ground plane. This kind of layer is only used for multilayer boards, mainly for laying power lines and grounding lines. We call them double boards, four boards and six boards, which generally refer to the number of signal layers and internal power/ground layers.

3 mechanical layer (mechanical layer)

Protel 99

SE provides 16 mechanical layer, which is generally used to set the mechanical information such as the external dimensions, data marks, alignment marks and assembly instructions of the circuit board. This information varies according to the requirements of the design company or PCB manufacturer. Executing the menu command Design | MechanicalLayer can set more mechanical layers for the circuit board. In addition, the mechanical layer can be attached to other layers to output the display together.

4 solder mask (solder mask)

Paint a layer of paint, such as solder mask, on all parts except the pads to prevent these parts from being tinned. Solder resist is used to match pads in the design process and is automatically generated. Protel 99 SE provides the top level.

Solder (top layer) and bottom solder (bottom layer).

5 solder paste mask layer (solder paste protective layer, SMD patch layer)

It is similar to solder mask, but the difference lies in the corresponding pads of surface mount components during machine welding. Protel99 SE provides top paste and bottom.

Paste (bottom) two layers of solder paste protection layer.

The most important point of Gerber output by pasting mask layer is that this layer is mainly for SMD components, and this layer is compared with the solder introduced above.

Mask to make a comparison and find out the different functions of the two, because the two film pictures are very similar.

6 shielding layer (no wiring layer)

Used to define the area on the circuit board where components and wiring can be effectively placed. Draw a closed area on this floor as the effective area of wiring, and it is impossible to automatically lay out wiring outside this area.

7 screen printing layer (screen printing layer)

Screen printing layer is mainly used to place printing information, such as the outline and label of components, various annotation characters, etc. Protel 99 SE provides a top cover and a bottom.

Covering two screen printing layers. Generally, all kinds of label words are on the top screen printing layer, and the bottom screen printing layer can be closed.

8 Multilayer (Multilayer)

The pads and vias on the circuit board should penetrate the whole circuit board and establish electrical connection with different conductive pattern layers, so the system specially sets up an abstract layer-multilayer. Generally speaking, pads and vias should be arranged on multiple layers. If this layer is turned off, pads and vias cannot be displayed.

9 Drilling layer (drilling layer)

The drilling layer provides drilling information during the circuit board manufacturing process (for example, pads and vias need to be drilled). Protel 99 SE provides Drillgride and Drill.

Draw (borehole diagram) two borehole layers.