1. Lack of planning With PCB layouts, preparation is the most important part of the job.  The amount of time spent preparing will affect the success of the design.  Selecting the right PCB design software is the most important; each having advantages, disadvantages and limitations. Each PCB is unique it it's own way. Some areas of the design are more important than the rest, for example power supplies, impedance signals, DDR, address and data bus.  If these areas are not completed before the rest of design, precious time is lost and considerable effort is then spent reworking the layout. Setting up rules and constraints are there to guide from the placement stage till the gerbers are completed.  When a PCB is planned correctly, the rest of the design will become a much simpler process.   2. Constraint rules There isn't anything more powerful than the human mind, unfortunately it is not perfect! There are lots of things to think about with a PCB design, and it is easy to get lost with all of the information.  By using the tools available from PCB software, constraints can be implemented; spacing, keepouts, length matching, propagation delays. Once these rules have been implemented, the designer can focus on other areas of the layout.   3. Poor Communication As PCBs become more complex, the communication between engineer and PCB designer is essential.  By eliminating any placement or routing issues early on can save on costly reworks. It is very important for the engineer to review the circuit board as often as possible.  Using on-line meeting tools can allow the engineer to inspect the board in real time and discuss potential issues. By setting out clear objectives and agreeing on them from the start of the layout can give the designer a better understanding of what you want to achieve and can shorten time-to-market.   4. Using ineffective layout techniques PCB layouts are becoming more complex thanks to advancements in electronic technology.  Problems such as electrical noise, crosstalk, impedance mismatch, timing issues, ESD - all need careful consideration. Practical PCB design rules, board stackup, PWR & GND planes, decoupling capacitors, faraday shields - these are valuable when used correctly. Reference designs provides the optimum solution to meet requirements for complex layouts.  Some of their suggestion may be difficult to achieve, but they do give some insight on how the PCB should be designed correctly.   5. Forgetting to backup…

Despite increasing levels of semiconductor integration and readily available systems-on-chips for many applications. In addition to the increasing availability of highly-featured development boards, electronics often still require a custom PCB. Even for “one-off” developments, the humble PCB still performs an important role. It’s a physical platform for a design, and the most flexible for pulling an electronics system together. In this article, we outline ten best practices of PCB design, most of which have stayed consistent for 25 years. These rules are in no particular order and applied to any PCB design project. This should prove as a useful guide both to veteran design engineers as well as makers alike…   Use the right grid Find a grid spacing that suits as many of your components as possible and use it throughout. Although multiple grids may seem appealing. A little additional thought at the early stages of the layout can avoid spacing difficulties and maximize board use. Many devices are available in different package sizes, so use that to your advantage. Furthermore, as the polygon is an important shape when adding copper to your board. Boards with multiple grids will often produce polygon-fill discrepancies, not standardizing on one grid can make your life difficult.     Keep trace lengths as short and direct as possible This rule applies even if it means going back over parts of the layout again to optimize track lengths. This applies particularly in analogue and high-speed digital circuitry where impedance and parasitic effects will always play a part in limiting your system performance.   Whenever possible, use a power plane to manage the distribution of power lines and ground. Using pours on the power plane is a quick and easy option in most PCB design software. It applies plenty of copper to common connections and helps ensure power flows as effectively as possible with minimal impedance or voltage drop. That ground return paths are adequate. If possible, run multiple supply lines in the same area of the board and remember that if the ground plane runs over a large section of one layer. It can have a positive impact on cross-talk between lines running above it on an adjacent layer.   Group related components and test points together Place the discrete components needed for an opamp close to that device so the bypass capacitors and resistors are co-located with it. This helps with the track…