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How To Conduct PCB CAM Engineering Work

Design for Manufacturability (DFM) Check

At Fuchuangke Technology, we check your PCB board design and confirm that it is ok for manufacturing with our free DFM check service. If customers don’t prepare well the printed circuit board (PCB) specifications, our CAM engineer will export the pertinent information from CAD data supplied with an RFQ. During CAM processing, some design issues may be found, which might cause your PCB order to be put on CAM hold during this review, because we don’t perform the complete CAM procedure at this time there may be some issues that are not identified until after your order is placed.

Basic Steps of Normalization Process:

Re-naming the Gerber files to our standard naming convention.

Checking to ensure that all necessary files are present.

Importing Gerber and NC drill files into our CAM software.

Reviewing that the PCB board’s specifications in the order match the data supplied.

Checking the specs of these Gerber files with our manufacturing capabilities

Check to see our full PCB manufacturing capacities:

 

MCPCB Capabilities

 

HDI PCB Capabilities

 

FPC and Rigid-Flex PCB Capabilities

 

FR4 PCB Capabilities

 

Outer Layers Check

Pads are removed for NPTHs, unless pads are much bigger than hole size.

Test Outside of outline is removed, or move to inside of outline.

The board outline is removed from artwork if present.

Pads are added for all holes that do not have pads for standard specifications as all holes are plated.

Copper extensions for gold fingers will be added to connect to gold bus bar.

Inner Layers Check

 

20mil clearance border will be added around negative inner layers for the outer edge. Clearances will be increased to 20mil (each side 10mil) over the hole size when possible around a drill hole and around the edge of a cutout. If all of these cannot be done without impacting the connectivity of the planes the order will be placed on hold. This is done to accommodate the inner layer clearance requirement at least 10mil from the edge of a hole to any adjacent copper on inner layers, and to prevent exposed copper.

Clearances that are smaller than the hole size are assumed to be intended as direct connections to the plane and will be removed.

On boards with edge fingers that will be beveled a 150mil clearance will be added along the edge that will be beveled. This is required to avoid exposed copper along the beveled edge.

Text outside of outline is removed.

The board outline is removed from positive artwork if present.

Drill Files

 

NPTH holes are identified and labeled.

Drill files are saved in a standard format.

Double drill hits (duplicate drills), and any drill hits with smaller drill hits inside them will be removed.

Drill chart tolerances that are all blank, or +/-0 will be ignored and the order type tolerances will be used instead.

Rout Files

 

CNC files can not be used for extracting data.

PCB board outlines on .GKO (Gerber Keep-out, outline) layers will need to be verified as the actual outline.

The largest diameter routing is 93mil (2.4mm) (used to produce 100mil spacing), using this bit reduces routing costs by allowing multiple panels to be simultaneously routed but will increase the PCB price in mass PCB board production.

The cutting path that the machine takes is called the NC route path; normally you need not to worry about it. You want to relay to manufacturing any specific cutting requirements you might have.

With regard to the PCB board and slot outlines. We would prefer to have these included in the Gerber files (solder mask and drill/fab files) with a line width 5mil or 10mil. This line width will not affect the PCB board price as the PCB board outlines are disregarded when the minimum trace width is determined.

Basic Vias Protection Fuchuangke Technology Supports

Exposed Vias

 

These will be processed with a clearance in the solder mask image that is equal to or greater than the via pad size plus 5mil solder mask swell.

If you have a requirement other than this, we can accommodate clearances as small as the finished hole size plus 5mil. Please include any specific requirement in the fabrication notes and/or order documentation.

These can be quoted and ordered with our standard parameters.

Unless prior arrangements have been made, PCB boards will be built based on the solder mask image files submitted.

Most design software packages have accommodation for including or excluding the vias from the solder mask image.

Tented Vias

 

These will be processed with no clearance in the solder mask image for the vias.

This will result in the pads being covered with solder mask and the holes may be open, partially plugged or completely plugged.

As we do not have dry film solder mask available, we cannot offer vias tented in such a way as to guarantee that all of the holes will be completely covered.

These can be quoted and ordered with our standard parameters. Unless prior arrangements have been made, the board will be built based on the solder mask image files submitted.

Most design software packages have accommodations for including or excluding the vias from the solder mask images.