1. The outer frame (clamping edge) of the custom pcb fabrication
should adopt a closed-loop design to ensure that the PCB panel will not be deformed after being fixed on the fixture.
2. The width of the custom pcb fabrication is less than or equal to 260mm (SIEMENS line) or less than or equal to 300mm (FUJI line); if automatic dispensing is required, the product of the width and length of the PCB board is less than or equal to 125 mm × 180 mm.
3. Custom pcb fabrication shape should be as close to square as possible. It is recommended to use 2×2, 3×3 jigsaw, but do not spell into yin and yang boards.
4. The center distance between the small plates is controlled between 75mm and 145mm.
5. When setting the reference positioning point, usually leave a non-resistive soldering area 1.5mm larger than the positioning point.
6. There should be no large devices or protruding devices near the connection point between the outer frame of the panel and the inner small plate, small plate and small plate. And the components and the edge of the PCB should leave more than 0.5mm space to ensure the normal operation of the cutting tool.
7. Four positioning holes are opened at the four corners of the outer frame of the panel, and the aperture is 4 mm ± 0.01 mm. The strength of the holes should be moderate to ensure that they do not break during the upper and lower plates. The aperture and position accuracy are high, and the hole walls are smooth and burr-free.
8. Each small board in the PCB panel must have at least three positioning holes. The aperture is greater than or equal to 3 mm and less than or equal to 6 mm. No wiring or patch is allowed within 1mm of the edge positioning hole.
9. Full board positioning for PCB and reference symbols for fine pitch device positioning.
In principle, QFPs with a spacing of less than 0.665 mm should be placed at their diagonal positions. The positioning reference symbols used for the imposition PCB sub-boards should be used in pairs and placed at the opposite corners of the positioning elements.
10. Large components should have positioning posts or positioning holes, such as I / O interface, microphone, battery interface, micro switch, headphone interface, motor and so on.