CAD file conversion Gerber file attention points

1. Protel for Windows should pay attention to the problem when switching to Gerber

1. 1. Use PFW to automatically generate D-code tables from PCB files. However, the table might contain hundreds of D-codes, so it's critical to know your photoplotter's D-code capacity before proceeding.
2. 2. If the D-code table isn't automatically generated by PFW, errors can occur under certain conditions:

• Zero-size pads or lines in the PFW file
• Relief-type pads present in the layout
• Missing 3D-code configuration

These situations may result in oversized D-codes appearing in the MAT file.

1. 3. If the .PFW file contains long octagonal pads, note that such D-codes should not appear in the D-code table after conversion. Most photoplotting systems don't accept this definition, and including it may lead to errors. Padding should be used to match the D-codes instead.
2. 4. For maximum reliability, it's better to use a user-defined D-code table rather than relying on automatic generation from PFW.

Before sending files for manufacturing, preview your output with the NextPCB Free Online Gerber Viewer to ensure all D-codes and layers are correctly generated and meet your photoplotter's specifications.

2. Protel for DOS should turn attention to the problem Gerber

1. The upper and lower limits of the .D code matching should not be set too wide, which is easy to cause too much deviation, so that the minimum spacing cannot be guaranteed.

2. Sometimes the Fill conversion can cause confusion. In this case, all the square D codes in the D code table should be deleted and then converted again.

3. When the D code does not match and requires manual matching, you must select mode 3.

4. When arc (arc) conversion, the step size (Arc Quality) should not be set too small, otherwise the data volume will be too large, and the arc edge is not smooth.

5. The solder resist expansion value can be a negative value.

6. Arc transformation can choose whether to describe the arc or a straight line.

Software Arcs: on is a straight line description, with a polyline approximating the arc when converting.

Software Arcs: off is a description of the arc, the true arc description.

For the ability to accept arc descriptions, it is best to use a circular arc description. In this way, the amount of Gerber file data is small, and the edge of the light drawing arc is smooth.

7. When more than 24 D codes are used, the G54 option should be turned on.

8. When the single-sided pad needs to be punched, open the Options\Single layer Pad Holes item.

9. Some tool software can generate a fully configured D code table from the MAT file.

3. PowerPCB should pay attention to the problem when transferring to Gerber.

1. There is a PowerPCB file that needs to be converted after copper padding.

2. PowerPCB is the PADS Windows version software, so it is basically the same as PADS in file conversion. The same problem is also to pay attention to observe which elements should be selected in each graphic to avoid the mistakes caused by the error.

4. PADS should pay attention to the problem when transferring to Gerber.

1. The capacity of the D code in the PADS preset D code table is too small and needs to be expanded.

2. There is a PADS file that needs to be converted after the copper fill.

3. Due to the particularity of the PADS software design line, it is necessary to pay attention to observe which elements should be selected in each graphic to avoid the mistake of turning out the graphic error.