Board design consists of several processes. First the electronic component’s PCB footprint need to be created. A PCB footprint defines the physical attribute of the component such as the pin spacing, pin numbering, length, width etc. so that the solder pads matches / aligns to the component when it is assembled on the PCB. The clearance for the part is defined at this point to ensure adequate space to avoid clashing with neighbouring components. Once the footprints are created, it is then assigned to the electronic components’ electrical symbol in the schematic diagram.
Next the parts are arranged in such a manner to optimise the trace length, PCB size, EMI, functionality and manufacturability. This is important especially if the PCB box or enclosure has been designed or being designed. The position of connectors, buttons and PCB mounting hole need to be in perfect alignment with the mechanical design. We will review with clients/mechanical engineers at this stage before the actual PCB routing takes place.
After this, PCB trace routing is carried out to connect the points from component pins as dictated in the electrical schematic diagram. This is a complex task for the PCB designer because the electrical rules and guidelines need to be followed. For example determining trace width, trace clearance, avoiding noisy paths, EMI consideration and manufacturing friendly design. Apart from the design rule check carried out, a layout review is performed with fellow engineers to check the component footprints, traces, copper pours to further improvise the design.
Once the PCB layout design is complete, Gerber file and assembly drawing is generated. The PCB Gerber file will be use at the next stage to manufacture the PCB. The assembly drawing will be later used for PCB assembly