1. After opening the V-groove, the remaining thickness X should be (1/4～1/3) the plate thickness L, but the thickness X must be ≥0.4mm. Restrictions can be used for boards with heavy loads, and lower limits can be used for boards with lighter loads.

　　2. The displacement S of the wound on the left and right sides of the V-groove should be less than 0 mm; because there are few reasonable thickness limits, the V-groove splicing method is not suitable for the board with a thickness of less than 1.3mm.

Mark point

　　1. When setting the standard selection point, generally vacate an unobstructed non-resistance area 1.5 mm larger than the periphery of the selection point.

2. Used to assist the electro-optical positioning of the smt placement machine. There are at least two different measurement points on the top corner of the PCB board with chip components. The measurement points for the electronic optical positioning of a whole PCB are generally on the top of the whole PCB. The relative position of the angle; the measurement point for the electronic optical positioning of the layered PCB is generally at the opposite position of the top corner of the layered PCB circuit board.

3. For the components of QFP (square flat package) with wire spacing ≤0.5 mm and BGA (ball grid array package) with ball spacing ≤0.8 mm, in order to improve the precision of the chip, it is stipulated to set at the two top corners of the IC Measuring point.

　　Four, processing technology side

1. The border between the frame and the internal main board, the node between the main board and the main board should not be too large or overhanging, and the edge of the electronic device and the PCBpcb circuit board should leave more than 0.5 mm of indoor space. To ensure the normal operation of the laser cutting CNC blade.

　　 5. Positioning holes on the board

1. It is used for the positioning of the entire PCB circuit board of the PCB circuit board and the standard mark for the positioning of the fine-spaced components. Under normal circumstances, the QFP with an interval of less than 0.65mm should be set at the top corner; used for the PCB sub-board The positioning standard marks of the board should be applied in pairs, arranged at the top corners of the positioning factors.

　　2. Positioning posts or positioning holes should be reserved for large electronic devices, such as I/O jacks, microphones, rechargeable battery jacks, toggle switches, earphone jacks, motors, etc.

　　A good PCB designer should take into account the elements of production and manufacturing when developing the puzzle design plan to ensure convenient production and processing, increase productivity, and reduce product costs.