Problems that need to be paid attention to in circuit board design

Editor:浙江睿索电子科技有限公司 │ Release Time:2021-05-24 

In the production of circuit boards, we often encounter a lot of products that do not meet the expected design due to design reasons. As a circuit board manufacturer, the film is designed by customers and printed on the circuit board. If it is a problem with the drawing, the circuit board manufacturer is also powerless. Let’s give an example today. In production, we often

Frequently encountered problems, how designers should design, the following are some examples, the most prone to problems, but there are also some minor problems, but the design is not so concerned about the problems that result.

1. The problem of golden hands opening windows: usually our golden fingers are used to open windows. If you want to open the window, you must design the drawing to open the window when designing, not to cover the oil. Because not all engineering personnel will confirm with you when the circuit board manufacturer produces, it is processed according to the data or opening the window.

2. Through hole cover oil problem: I often encounter customer complaints. My board needs to be covered with oil. Why is the window open? We check the design drawings. The result is that the drawing is windowed. For those that need through hole cover oil, When designing, it must be designed to be covered with oil, and the window cannot be opened. If you did not notice that you opened the window, then the finished product must also be windowed.

For those that must open the window as a test point, please be careful not to cover the oil.

3. Character problem: We often encounter the problem that characters are too small to be printed. If they are too small, they will be printed as one piece and cannot be seen clearly. The minimum character size required by the circuit board manufacturer is 0.8*1.5MM. The minimum size is this size, and it will be unclear if it is smaller than the size. The other is that the characters cannot be placed on the pads, and all the characters on the pads need to be removed.

4. Via-to-line and via-to-hole issues: In the design, at least a 0.2mm spacing between vias and lines should be ensured, and a 0.3mm spacing between holes and holes. In the production process, vias, pads, and lines are all Need compensation. The original drawings need to be spaced to facilitate compensation in the processing of the production drawings. If the production drawings are not compensated, the finished product will be smaller than the design after etching.

5. Distance from hole and line to the edge of the board: It is often encountered that some design holes and lines are next to the contour line. Generally, the distance from the line to the shape should be kept above 0.5mm to ensure that the line has position compensation and the shape will not reach the line when making the shape. The hole to the profile line is more than 0.5mm, and position compensation is reserved. Less than 0.5MM will cause the edge of the finished product

Expose copper, if the edge of the board does not accept exposed copper, it needs to be processed by copper extraction, and the pad will be slightly smaller after copper extraction.