Designing 4 Layer Circuit Boards
A 4 layer circuit board is one of the most common variants in a printed circuit board. This design is popular among manufacturers because it allows for the balance of power, signal and ground layers needed to meet performance specifications. In addition, these PCBs are generally more cost-effective than their 6-layer counterparts.
Using a software program to design a 4 layer circuit board can be challenging for beginners, but there are many different programs available that can help with the process. Some are free to use and others require a subscription fee for continued usage. Each program has its own set of benefits and features, but most have a similar basic feature set that makes them suitable for creating a 4 layer circuit board.
To begin designing a 4 layer circuit board, start by opening the PCB editor and selecting “Add Layer”. This will add the top and bottom layers, both of which are signal layers. Next, click on the Layer Manager tab at the top of the interface to view the layer distribution. There are two options on the right, “Add Layer” and “Add Plane”. Add Layer adds a new signal layer while Add Plane adds an internal electric layer (negative film).
The software’s stackup designer will then automatically create the layers and their assigned networks. The stackup design will also determine the impedance of conductors on the surface layer, making it easier to route high-speed signals without causing interference between them and other components. The integrated field solver from Simberian will also enforce target impedance during routing, which will be crucial for meeting performance specifications.
Software Used For Designing 4 Layer Circuit Boards
Once the layer stack and electrical design is complete, users can move onto the layout phase. This is where the design will come to life on the screen as users begin connecting traces and assigning connections to nets. Altium Designer has a robust routing engine that supports multiple routing modes such as obstacle avoidance, hug, and hug-n-push. The software will also enable the creation of differential pairs and accordions. The router will also apply clearances for critical features such as vias and pads.
Altium Designer includes a library with pre-designed parts that can be used to quickly build up a component list. The component list can then be sent off to manufacturers for a quote to fabricate and assemble the finished product. The software also has a one-click manufacturing button that will directly send gerber files to manufacturers for a bare board prototype or full production run.
Other programs that can be used for drawing a 4 layer circuit board include EasyEDA, Eagle and KiCad. All of these software programs have their own strengths and weaknesses, but each is capable of creating a basic PCB for most applications. The free version of DipTrace is limited to 300 max pins and 2 layers, but offers a schematic capture with component links to libraries, an electrical rule check, and importing/exporting capabilities that allow for the transfer of files between other CAD programs.