CAD file conversion Gerber file attention points

writer: G March 28, 2019

(A) Protel for Windows should pay attention to the problem when switching to Gerber

1. Use PFW to automatically generate D code tables based on PCB files. However, there may be as many as hundreds of D codes in the D code table. In this case, you should know exactly what the D code capacity of your photoplotting system is.

2. If the D code table is not automatically generated by PFW, the following conditions may cause an error:

1. There may be a 0 pad or line in the PFW;

2. When there is a Relief type pad;

When the 3D code is not configured.

In the above case, a large D code will appear in the MAT file.

3. There is a long octagonal pad in the PFW. There should be no such D code in the D code table during conversion. Since this definition is not accepted in most current photoplotting systems, the appearance of such D codes can lead to errors. In this case, the D code should be matched by padding.

4. It is best to use a user-defined D code table instead of using PFW to automatically generate a D code table.

(B) Protel for DOS should pay attention to the problem when switching to 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 may 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. In the arc conversion, the arc quality should not be set too small, otherwise the data volume will be too large, and the arc edge will not be smooth.

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

6. Arc conversion can choose arc description or line description.

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.

(C) Pay attention to the problem when PowerPCB is transferred to Gerber.

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

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 graph to avoid mistakes and make out of graphics errors.

(D) Pay attention to the problem when PADS is transferred 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 graph to avoid the mistakes caused by the mistakes.


  • PCB
  • SMT
  • Stencil

Dimensions:(mm)

×

Quantity:

Layers:

Thickness:

Quote now