In PCB silk screen design, it mainly includes: component silk screen, board name, version number, barcode silk screen, mounting hole positioning hole silk screen, board direction mark, anti-static mark, positioning identification point, etc. Today, we mainly learn about the requirements for component silk screen design.
General requirements for silk screen design
1) In order to ensure that all letters, numbers and symbols are easy to identify on the PCB, the line width of the silk screen must be greater than 5mil and the silk screen height must be at least 50mil.
2) Silk screen is not allowed to overlap with pads and reference points.
3) White is the default silk screen ink color. If there are special requirements, it needs to be stated in the PCB drilling diagram file.
4) In high-density PCB design, the content of the silk screen can be selected as needed.
5) The arrangement direction of the silk screen string is from left to right and from bottom to top.
Requirements for component silk screen design
1) All components, mounting holes, positioning holes and positioning identification points have corresponding silk screen labels, and the positions are clear and clear.
2) For components with polarity or installation direction on the PCB, their polarity and direction should be reflected on the silk screen.
3) The distance between the silk screen and the places where soldering is required, such as SMT pads, plug-in solder holes, test points, and reference points, should be at least 0.4mm.
4) For the convenience of inspection, the silk screen characters, polarity and direction silk screen symbols cannot be covered by components or handles.
5) If the silk screen symbols of some components can only be cancelled due to space limitations on the PCB, it must be ensured that the silk screen symbols of these components are on the assembly drawing of the PCB. Locate the components through the assembly drawing.
How to quickly set the silk screen size of components?
In Pads, press Ctrl+Alt+F to open the selection filter (Filter), remove other check options, select only Labels, then use the mouse to select the silk screen you want to modify, right-click and select properties, and the setting window pops up. Modify the “Size” and “Line width” you need.