What problems will be encountered in PCB proofing design? The following is a summary of ten problems that are easy to encounter in PCB proofing design.

Common Problems in PCB Proofing Design

1、 Pads overlap

Pads overlap, which means holes overlap. During drilling, the hole will be damaged and scrapped due to repeated drilling in one place.

2、 Drawing Layer Abuse

Specific performance: some useless connections have been made on some graphic layers, but the original design of the four layer board is more than five layers of circuits, causing misunderstanding; Violation of conventional design, such as the design of component surface at the bottom, and the design of welding surface at the top, causing inconvenience. Therefore, the design should keep the drawing layers complete and clear.

Third, the characters are misplaced.

Specific performance: SMD pad of character cover brings inconvenience to on-off test of circuit board and welding of components; Also, the character design is too small, which makes screen printing difficult; Too large will make the characters overlap and difficult to distinguish.

IV. Single side pad aperture setting

Single sided cushion is generally not drilled. If it is required to drill holes for marking, its aperture shall be designed as zero. If the numerical value is designed, the hole coordinates will appear at this position when the drilling data is generated, which will cause problems.

5. Use the filler block drawing board.

The circuit design can pass DRC inspection, but processing is not feasible. When the solder mask is applied, the area of the filler block will be covered by the solder mask, which will make it difficult to weld the device.

6. There are too many filler blocks or the filler blocks are filled with very thin lines in the design.

Easy to cause: loss of light rendering data, incomplete light rendering data, or large amount of light rendering data generated, which increases the difficulty of data processing.

7、 The pad design is too short.

This is for switch test. For surface mount devices that are too dense, the distance between the two pins is relatively small, and the bonding pad is relatively thin. To install test pins, they must be staggered up and down (left and right). If the pad design is too short, the device installation will not be affected, but the test pin will not open.

8、 Large area grid spacing is too small

Large area grid spacing is too small (less than 0.3mm). In the manufacturing process of the circuit board, after the wire drawing process is completed, it is easy to produce a lot of broken films pasted on the board, resulting in wire breakage.

IX. Large area copper foil is too close to the outer frame

The distance between the large area copper foil and the outer frame shall be at least 0.2mm, otherwise the copper foil may be warped and the solder mask may fall off.

10. Abnormal hole is too short.

The length/width of special-shaped hole shall be 2:1, and the width shall be<1.0mm; Otherwise, the drilling machine is very easy to break the drill when processing the special-shaped hole, causing processing difficulties and increasing costs.

The above are the problems that are easy to encounter in PCB proofing design. Do you understand them all?