7 Factors to Consider for a Good Quality PCB Design

For most Electronic Engineers (EEs),designing PCB is a regular task. Although they may have years ofexperience in PCB design, it is not easy to create a high quality PCBdesign. A lot of factors need to be taken into consideration. Here wewill discuss seven factors to be considered for a quality PCB design.

7 Tips for a High-quality PCB Design

Following are the seven main points thatan EE or a novice should keep in mind, if they wish to design qualityPCBs for their electronic applications.

1. Board Materials: This is a cornerstone of any PCB design project. You need to understand what materials you will require to create your PCB.
   • A PCB comprises of a non-conductive, and solid material, which islaminated with copper. The copper plating helps create a conductivesurface. The base material is usually a glass-reinforced epoxy, which isFR-4. This material is affordable and flame resistant.
   • In RF or high performance circuits, PTFE or ceramic bases are used along with various fillers.
2. PCB stack-up: The PCB stack-up implies number oflayers each PCB will have. It allows an EE to understand requiredimpedance of each layer. Appropriate estimation of the layer countallows the engineer to make decision about the right fabricationprocess, and achieve the desired yield, reliability, and minimize theproduction costs.
3. Copper Traces: The traces made from copper arethe most important components on a PCB. It is very important tounderstand their properties, as well as their limitations, whiledesigning them. The copper traces are usually created by removing somecopper from the solid metal sheet that is placed on the base material.
4. Via Types: Vias are the crucial elements in anyPCB because they help establish the connections between differentcomponents. There are various types of Vias that you need to know about:Buried, Through, Blind, and Micro (stacked, multi, and single layer).In the best PCB designs, vias are minimized. You also need to understandthe current carrying abilities of these vias.
5. Selecting Parts: This is the most tedious step in any PCB design project. Choosing the right part will help minimize errors, and ensuresquality of the designed PCB. Since, there are millions of componentsavailable in the market, you need to keep the following things in mind:
   • Select a part, which is used widely, and easily available. Avoid using a component, which is no more in production.
   • Some parts are sold in large numbers, so be aware, when selecting them for your project.
   • All components are offered in a type of package, which helps EE’sto attach them to the PCB. Some parts are available in multiplepackages, which may make them compatible.
6. Rules for Design: After addressing all the aboverequirements, an EE should concentrate on the design rules. There shouldbe a broad consideration about the cross-talk budgets, componentplacements, layer allocations, time of flight analysis, Design forManufacture (DFM) rules, etc.
7. Signal & Power Integrity: This is consideredas one of the good aspects of a quality PCB. There are various aspectsto be considered, such as signal fall and rise times, drive strength,track lengths, and characteristic impedance. To ensure the qualityperformance, signal-integrity (SI) simulations will be performed pre andpost layout.

High performance electronic circuitsrequire large currents. So, AC and DC performance of the powerdistribution network should be considered.

The above list gives a good startingpoint for an experienced EE, as well as a novice. We will consider someof these points in our forthcoming blogs, and also guide you throughtasks of assembling PCBs.