1. The outer frame (clamping edge) of PCB panel shall adopt closed-loop design to ensure no deformation after being fixed on the fixture;

2. PCB panel width ≤ 260mm (Siemens line) or ≤ 300mm (Fuji line); if automatic dispensing is required, PCB panel width × length ≤ 125mm × 180mm;

3. The shape of PCB panel should be close to the square as much as possible. 2 × 2, 3 × 3 But don't make the yin-yang board;

4. The center distance between small plates shall be controlled between 75 mm and 145 mm;

5. When setting the reference locating point, a non resistance welding area 1.5mm larger than the locating point is usually reserved around the locating point;

6. There shall be no large devices or protruding devices near the connection point between the outer frame and the inner small board of PCB panel, and there shall be more than 0.5mm space between the components and the edge of PCB panel to ensure the normal operation of cutting tools;

7. Four positioning holes shall be made at the four corners of PCB panel outer frame, with the hole diameter of 4mm ± 0.01mm; the strength of the holes shall be moderate to ensure that they will not break during the process of upper and lower board; the hole diameter and position accuracy shall be high, and the hole wall shall be smooth without burr;

8. Each small board in PCB panel shall have at least three positioning holes, 3 ≤ hole diameter ≤ 6 mm, and no wiring or patch is allowed within 1 mm of edge positioning hole;

9. 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;

10. Large components shall be provided with positioning column or positioning hole, especially I / O interface, microphone, battery interface, microswitch, headphone interface, motor, etc.