General requirements for screen printing
1. The line weight of screen printing should be greater than 6 mil, and make sure character height could be visible to the naked eye (height greater than 50 mil is recommended).
2. The distance between screen printing at least 8 mil.
3. Screen printing must not overlap the bonding pad and the mark, and there is at least a distance of 6 mil to be left between the two items.
4. In the high density PCB design, one can choose the screen printing content according to the needs. Character string should be arranged in accordance with the rules of from top to bottom, left to right of timing.
5. Thumb wheel switch or contact pin could change the status of components through hardware settings, the screen printing layer should indicate the PIN number, working condition and usage. Screen printing should be printed on the side of component.
The content of screen printing
Printing screen content on the printed plate includes:
1. Identifying information (PCB name, version, company logo)
2. Component number, component polarity and direction signs
3. Mounting hole position signs
4. Plate direction signs, first pin signs of the connector and component position;
5. Anti-static signs
6. Explosion-proof marks
7. Specifications and models of certain components (battery, fuse…) and etc.