1. 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;
2, PCB board width ≤ 260mm (SIEMENS line) or ≤ 300mm (FUJI line); if automatic dispensing is required, PCB board width × length ≤ 125 mm × 180 mm;
3, PCB layout as close to the square as possible, it is recommended to use 2 × 2, 3 × 3, ... puzzle; but do not spell into a yin and yang;
4. The center distance between the small plates is controlled between 75 mm and 145 mm;
5. When setting the reference positioning point, usually leave a non-resistive soldering area 1.5 mm 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 space between the components and the PCB should be more than 0.5mm. 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. The hole diameter is 4mm±0.01mm. The strength of the hole should be moderate to ensure that it will not break during the upper and lower plates. The aperture and position accuracy are high, and the hole wall is smooth and burr-free. ;
8. Each small plate in the PCB panel must have at least three positioning holes, 3≤ aperture ≤6 mm, no wiring or patch is allowed within 1mm of the edge positioning hole;
9. The whole board positioning for PCB and the reference symbol for fine-pitch device positioning. In principle, the QFP with a pitch less than 0.65mm should be set at its diagonal position; the positioning reference symbols for the imposition PCB sub-board should be paired. Used, arranged at the opposite corner of the positioning element;
10, large components should be left with positioning posts or positioning holes, such as I / O interface, microphone, battery interface, micro switch, headphone interface, motor, etc.;
The difference between PCB and PCBA
What is a PCB? How did PCBA evolve? What is the difference between PCB and PCBA? Let's take a closer look below.
PCB is the abbreviation of Printed Circuit Board. Because it is made by electronic printing, it is called "printing" circuit board. PCB is an impor...