Basic Process And Skills of PCB Processing (3)

12. Place the copper clad area

Temporarily change the safety spacing in the design rules to 0.5-1mm and clear the wrong mark, select Place-Polygon Plane to place the copper cladding of the ground network on each wiring layer (try to use octagons instead of arcs to wrap the pads. If you want to convert it to DOS format file eventually, you must choose to use octagon). The following figure is an example of a setup for placing copper on the top layer:

After the setting is completed, press OK again to draw the border of the area that needs to be covered with copper. The last edge can be left unpainted. Just press the right mouse button to start the copper-covering. It defaults that your start and end points are always connected by a straight line. When the circuit frequency is high, the optional Grid Size is larger than the Track Width, and the grid lines are covered.

Place the copper cladding of the other wiring layers accordingly, observe the large area on one layer where there is no copper cladding, place a via hole where there is copper cladding on other layers, double-click any point in the copper cladding area and select a copper cladding. , directly click OK, and then click Yes to update the copper coating. Several copper claddings are repeated several times until each copper cladding layer is full. Change the safe spacing in the design rule back to its original value.

13. Do DRC again

Select Clearance Constraints Max/Min Width Constraints Short Circuit Constraints and Un-Routed Nets Constraints, press the Run DRC button, and correct any errors. Save it after everything is correct.

14. For manufacturers that support PROTEL99SE format (PCB4.0) processing, they can export this file as a *.PCB file when viewing the document directory; for manufacturers that support PROTEL99 format (PCB3.0) processing, the file can be exported Save as PCB 3.0 binary file and do DRC. Exit without saving after passing. Export this file as a *.PCB file while viewing the document directory. Since a large number of manufacturers can only make boards drawn by PROTEL AUTOTRAX under DOS, the following steps are necessary to generate a DOS version PCB file:

1. Change the contents of all mechanical layers to mechanical layer 1. When viewing the document directory, export the netlist as a *.NET file. When viewing this PCB file, export the PCB to PROTEL PCB 2.8 ASCII FILE format *.PCB files.

2. Open the PCB file with PROTEL FOR WINDOWS PCB 2.8, select Save As in the File menu, and select Autotrax format to save as a file that can be opened under DOS.

3. Open the file with PROTEL AUTOTRAX under DOS. Individual strings may need to be re-dragged or resized. All two-pin SMD components placed up and down may cause the X-Y size of the pads to be interchanged, adjust them one by one. The large four-column SMD IC will also have all the pads X-Y interchanged. It can only be automatically adjusted by half, and then manually changed one by one. Please save it at any time. Human errors are easy to occur in this process. PROTEL DOS version does not have UNDO function. If you have previously laid copper and chose to wrap the pads with arcs, then all the networks are basically connected now. It is very tiring to delete and modify these arcs one by one manually, so it is recommended that you must Wrap the pads with an octagon. After all these are completed, use the previously exported network table as the Separation Setup in the DRC Route. The values ​​should be smaller than those in the WINDOWS version. If there are errors, correct them until all the DRCs are passed.

You can also directly generate GERBER and drilling files and send them to the manufacturer to select File-CAM Manager and press the Next> button to display six options, Bom is the list of components, DRC is the design rule check report, Gerber is the light drawing file, and NC Drill is the drill. Hole file, Pick Place is automatic pick and place file, Test Points is test point report. After selecting Gerber, follow the prompts to proceed step by step. Some of the parameters related to the production process capability need to be provided by the printing plate manufacturer. until Finish is pressed. Right-click on the generated Gerber Output 1, select Insert NC Drill to add drilling files, then right-click and select Generate CAM Files to generate the real output file. The light-drawing file can be exported and opened with CAM350 and verified. Note that the power plane is output from the negative film.

15. Send Email or copy to the manufacturer

Indicate the board material and thickness (when making a general board, the thickness is 1.6mm, the extra-large board can be used 2mm, the microstrip board for RF is generally about 0.8-1mm, and the dielectric constant of the board should be given indicators), quantity , Special attention should be paid to the processing. Call the manufacturer within two hours after the email is sent to confirm whether it has been received or not.

16. Generate a BOM file and export it and edit it into a format that conforms to the company’s internal regulations.

Seventeen, the frame screw hole connectors and other parts related to the machining of the chassis (that is, first select other irrelevant parts and delete them)

Export to AutoCAD R14 DWG format file with metric dimensions for mechanical designers.

17. Organize and print various documents.

Such as parts list, device assembly drawing (and should note the printing scale), installation and wiring instructions, etc.