Before the manufacturing process, the PCB manufacturers receive the designer’s files in different file formats. This file is the concept of the required PCB that will be provided by the design engineers to the PCB manufacturers. This file contains the information of the component insertion, wire wrapping, routing and all the design details of the required PCB.
The computer-aided manufacturing (CAM) software analyses these files and identifies the file format. Right after this, the artwork layers and the drilling data are recognized. If there is an instance of a missing file, the work will be put on hold and the customer will be notified about the issue. Subsequently, Design Rule Checking (DRC) will be done.
CAM is a subsequent tool implemented after the CAD. CAM is for the precise manufacturing process while CAD is for designing the PCB. Generally, CAM is implemented by the manufacturer whereas CAD (PCB designing tool) is implemented by the design engineers.
CAM software supports for both prototyping and line production. The primary aim is numerically controlled drilling and component insertion. In numerical control, a computer-based controller translates a sequential list of codes into instructions that can be understood by the machine tools.
The whole concept can be summarized as computer-assisted manufacturing. When all the design parameters are fulfilled, the design will be put into production.
The netlist file (formatted as IPC-356) is nothing more than an ASCII text file that includes instructions for the PCB CAM software such as net names, pins, and XY locations of start and end points for each net or node.
A netlist is a list of nets which define the conductivity interconnection scheme of a bare circuit board.
The CAD netlist is the original netlist extracted from the basic schematic captured and supplied by the designer from the CAD software database. The CAD netlist can be received in various formats, for example:
- Mentor Graphics neutral file