10 PCB puzzles are not secrets
The outer frame (clamping edge) of the PCB panel should adopt a closed loop design to ensure that the PCB panel will not be deformed after being fixed on the fixture.
PCB panel width ≤ 260mm (SIEMENS line) or ≤ 300mm (FUJI line); if automatic dispensing is required, PCB board width × length ≤ 125 mm × 180 mm.
The shape of the PCB is as close as possible to the square. It is recommended to use 2×2, 3×3... puzzles; but do not spell the yin and yang boards.
The center distance between the small plates is controlled between 75mm and 145mm.
When setting the reference positioning point, usually a non-resistive soldering area 1.5 mm larger than the positioning point is left.
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 space between the components and the PCB should be more than 0.5mm to ensure The cutting tool is operating normally.
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.
Each small plate in the PCB panel must have at least three positioning holes, 3≤ aperture ≤6mm, and no wiring or patch is allowed within 1mm of the edge positioning hole.
For full board positioning of PCBs and reference symbols for fine pitch device positioning, in principle QFPs with a pitch 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.
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.