A printed circuit board, or PCB, is a blank circuit board upon which circuit-mounted components such as capacitors, resistors, transistors and potentiometers are mounted. Blank boards are typically used in self-assembly projects, to make circuit assembly quicker and easier for the end-user. A fabrication drawing tells the board manufacturer exactly how you want your board to look, including information about dimension, connection, and holes. Each board has its own connection and dimension specifications. It's prudent to follow certain best practices when having your board fabricated. This reduces the chances of design flaws and manufacturing mistakes in your PCB.
Plot Signal Chain Left to Right
The signal chain refers to the sequence of components from power supply through to the output. A circuit may not always be linear, for example it may have branches. But for the purposes of accuracy, your fabrication should denote the intended signal chain in a linear fashion. This way the manufacturer knows exactly where to include copper conductor strip material. This is metal the runs along the base of the PCB, between the turrets. The conductor strip carries current between the board-mounted components. If portions of conductor strip are missing, the fabricated circuit won't work.
Use a Gerber File
Gerber files are the industry standard file type of PCB fabrication drawings. Gerber files are specifically configured to allow you to include layered drawings. This permits you include various drawings which the manufacturer can superimpose on each other to create a complete representation of the board layers, including solder mask, hole size and connection type. A Gerber file generator lets you select industry-standard specifications, so rather than drawing each hole to size, you select from a drop-down menu of industry recognized hole dimensions.
Dimension Outline
Your drawing should include board dimensions in millimeters. While this sounds like an obvious step, if the information is missing the fabrication software used to cut your board may revert to default dimensions and cut your board to the wrong size.
Define Hole Location
The location of the holes on the board are crucial to the success of any circuit board assembly project. Position them too close and components won't fit onto the board, position them too far apart and the end-user may run out of room on the board during the population stage.
Use PC-6012 Specifications
These are a set of industry-standard PCB board fabrication specifications. Using terms, for example "table 3-9" when referring to conductor thickness, you remove the potential for misinterpretation. These specifications are clearly defined by the Association Connecting Electronics Industries.
