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1、 The definition of processing level is not clear

The single panel is designed on the TOP layer. If it is not explained in the front and back, it may be difficult to install components on the board and weld it.

2、 Large area copper foil is too close to the outer frame

The distance between the large area copper foil and the outer frame should be at least 0.2mm, because when milling the profile, if the copper foil is milled onto the copper foil, it is easy to cause the copper foil to warp and the solder resist to fall off.

3、 Drawing pads with filler blocks

Drawing pads with filler blocks can pass the DRC inspection when designing the circuit, but not for processing. Therefore, such pads cannot directly generate solder mask data. When applying solder mask, the filler block area will be covered by solder mask, resulting in difficulty in device soldering.

4、 The electrical layer is both a flower pad and a connecting line

Because the power supply is designed as a rosette pad, the ground is the opposite of the image on the actual printed board, and all the connections are isolation lines. When drawing several groups of power supply or several kinds of ground isolation lines, be careful not to leave a gap, so that the two groups of power supply can be short-circuited, and the connection area can not be blocked.

5、 Character scrambling

The SMD pad of the character cover pad brings inconvenience to the on-off test of the printed board and component welding. The character design is too small, which makes screen printing difficult, and the characters overlap with each other, which is difficult to distinguish.

6、 Surface mount device pad is too short

This is for on-off testing. For devices that are too tightly surface mounted, the spacing between their two legs is relatively small, and the pads are also quite thin. When installing test pins, they must be staggered up and down. If the pad design is too short, it will not affect device installation, but it will cause the test pins to be misaligned.

7、 Single-sided pad aperture setting

Generally, the single-sided pad is not drilled. If the drilling needs to be marked, the hole diameter should be designed as zero. If the numerical value is designed, the hole coordinate will appear at this location when the drilling data is generated, and the problem will occur. The single-sided pad, such as drilling, shall be specially marked.

8、 Overlap of pads

In the drilling process, the drill bit will be broken and the hole will be damaged due to multiple drilling at one place. The two holes in the multilayer board overlap, and after the negative is drawn, it is shown as an isolation disk, resulting in scrapping.

9、 Too many filler blocks in the design or filler blocks are filled with very thin lines

There is a loss of photo data and the photo data is incomplete. Because the filling block is drawn one by one in the photo data processing, the amount of photo data generated is quite large, which increases the difficulty of data processing.

10、 Graphics layer abuse

"Some useless wiring has been made on some graphics layers, but originally a four layer board has been designed with more than five layers of wiring, causing misunderstanding.". Violation of conventional design. The graphic layer shall be kept complete and clear during design.