10 tips about PCB panel :
1. PCB panel width ≤ 260mm (Siemens line) or ≤ 300mm (Fuji line); if automatic dispensing is required, PCB panel width × length ≤ 125mm × 180mm.
2. The shape of PCB panel shall be close to the square as much as possible, and it is not allowed to assemble the male and female panels.
3. The outer frame (clamping edge) of PCB panel shall adopt closed-loop design to ensure that the PCB panel is fixed on the fixture to ensure no deformation in the future.
4. The center distance between small plates shall be controlled between 75mm and 145mm.
5. There shall be no large device or protruding device near the connection point between the outer frame of panel and the inner small board, and there shall be more than 0.5mm space between the edge of components and PCB board to ensure the normal operation of cutting tools.
6. Four positioning holes shall be made at the four corners of the outer frame of the panel, with the hole diameter of 4mm ± 0.01mm; the strength of the holes shall be moderate to ensure that there will be no fracture in the process of upper and lower plate; the hole diameter and position accuracy shall be high, and the hole wall shall be smooth without burr.
7. Each small board in the PCB panel shall have at least three positioning holes, 3 ≤ hole diameter ≤ 6mm, and the edge positioning hole cannot be wired or pasted within 1mm.
8. In principle, QFP with a spacing of less than 0.65mm shall be set at its diagonal position for the whole board positioning of PCB and for the positioning of thin spacing devices; the positioning reference symbols used for the sub boards of composite PCB shall be used in pairs and arranged at the diagonal position of positioning elements.
9. when setting the reference positioning point, a non resistance welding area 1.5mm larger than the positioning point is usually reserved around the positioning point.
10. Large components should be kept.
Generally, there are no more than 4 kinds of plate splicing requirements. The number of layers, copper thickness and surface finishing technology requirements of each type of plate are the same. In addition, negotiate with the manufacturer's engineer to reach the most reasonable splicing plan. After splicing, it should not be too soft. After splicing, it should be ensured that there is enough lateral support force. Splices are susceptible to moisture. After breaking it off, use a file to smooth it.
When do panel of PCB, pay attention to edge reservation and slotting. The purpose of edge reservation is to have a fixed place for later welding of plug-ins or patches, and the purpose of slotting is to split the PCB board. The process requirements for edge reservation are generally 2-4mm, and the components shall be placed on the PCB according to the maximum width. Slotting is to forbid the wiring layer or material layer. Specifically, it is agreed with PCB manufacturer for processing and marking by the designer.
V-groove and slotting are both a way of milling the profile. It is easy to separate multiple boards in the process of assembly to avoid damaging the circuit board in the process of separation. According to the shape of your single assortment to determine which way to use, V-CUT needs to go straight, not suitable for four different sizes of boards.
Panel size design
Panel size design refers to the assembly of some irregular and deformed PCB boards to reduce the waste of PCB board. Combined with the processing capacity of various processing equipment in PCB Factory, referring to the size specifications of the board, the panel size that can meet the company's requirements of the best quality of the board, the lowest production cost, the highest production efficiency and the highest utilization rate of the board is designed.
Factors influencing the size design of mosaic
Finished product unit size, shape, processing method, surface treatment method, number of layers, finished plate thickness, special processing requirements, etc.
The lamination mode (main influencing factors) of multilayers board, the on-off mode of panel splicing, the mode of pipe position, the processing capacity of each process equipment, the processing mode of shape, etc.
Sheet size specification, B sheet size specification, dry mold size specification, RCC size specification, copper foil size specification, etc. provided by raw material manufacturer.