what need to pay attention when designing PCBA

1. There is no silk screen on the tin position.

2. The minimum distance between the copper foil and the edge of the board is 0.5mm, the minimum distance between the component and the edge of the board is 5.0mm, and the minimum distance between the pad and the edge of the board is 4.0mm.

3, the minimum gap of copper foil: single panel 0.3mm double panel 0.2mm.

4. When designing the double panel, pay attention to the components of the metal casing. When the insert is in contact with the printed board, the top layer of the pad should not be opened, and it must be covered with solder resist oil or screen printing oil.

5. Do not place jumpers under the IC or under the components of the motor, potentiometer and other large-volume metal casings.

6, electrolytic capacitors can not touch the components of heat. Such as high-power resistors, thermistors, transformers, radiators. The minimum spacing between electrolytic capacitors and heat sinks is 10mm. The distance between other components and the heat sink is 2.0mm.

7, large components (such as transformers, electrolytic capacitors with a diameter of 15mm or more, high-current sockets.) should increase the pad.

8. The minimum line width of copper foil: 0.3mm for single panel, and minimum for 1.0mm for 0.2mm on the side of double panel.

9. There should be no copper foil (except for grounding) and components (or according to the structural drawings) within 5mm of the screw hole radius.

10. The pad size (diameter) of the general through-hole mounting assembly is twice the aperture. The minimum of the double-panel is 1.5mm. The minimum of the single-panel is 2.0mm. If the circular pad cannot be used, the pad of the waist can be used.

11. If the distance between the center of the pad is less than 2.5mm, the screen of the adjacent pad should be wrapped with silk screen oil. The width of the screen printing oil is 0.2mm.

12. Components that need to be soldered after soldering. The pad should be turned away from the tin. The direction is opposite to that of tin. It is 0.5mm to 1.0mm. This is mainly used for the soldering of the single-sided and post-weld. Blocked.

13. In the large-area PCB design (above more than 500cm), in order to prevent the PCB board from bending when the tin furnace is over, a 5mm to 10mm gap should be left in the middle of the PCB board (the line can be routed) for use. A tin bar that prevents bending is added to the tin furnace.

14. In order to reduce the short circuit of the solder joint, all the double panels and via holes do not open the solder mask.