Printed circuit boards (PCBs) are the base layers of all electronic equipment. A PCB is a circuit’s skeleton, upon which you add layers of components, eventually creating the functional product.
While designing an electronic product, developers will identify a need – or an operation that the product should carry out. From this need they will create a concept, and then – once the idea becomes more concrete – a schematic.
The first stage of the PCB production process is capturing a circuit schematic. This has become easier as PCB technology has improved. Veteran designers may remember sketching out PCB layouts with black tape on film.
Nowadays, PCBs can be designed and altered on specialist CAD software. More premium software packages have built in schematic-capture tools. Budget software packages are available to amateurs who do not wish to pay as much for programmes. However, you may need a range of programmes to capture the schematic and convert it into a desktop design.
Before producing a detailed PCB layout, efficient designers should produce a rough diagram of where components will be placed. This allows them to make decisions about the number of layers and the size of board required for the particular ‘need’.
A more detailed PCB design will then draw up a more detailed component placement diagram taking into account thermal management, function and electrical noise considerations. Following this a placement review should be held and adjustments made to facilitate routing and optimise performance.
Once you have a basic placement formulated you can begin to map the routes between the components. Routing itself involves establishing the connections, or tracks between different holes where components will eventually sit. Most PCB software packages will allow you to route the physical connections on the board automatically according to the schematic.
When routing is complete the design can be saved and exported as a Gerber file before seeking final approval and sending the design to your desired prototype manufacturing house.
Once complete, it is important to test the PCB design with all components to see if it meets the original ‘need’ and functions properly. Developers should take account of feedback from tests before altering designs and restarting the process.
