common design flaws to watch out for in PCBs
Printed circuit board (PCB) designers have a crucial role in bridging the gap between conceptual designs and functional devices. They are responsible for implementing the design rules and constraints that are entered into CAD tools to ensure that all components will fit and that manufacturing will go smoothly. However, even the most experienced designers can make mistakes that impact a PCB’s functionality and performance.
Here are six common design flaws to watch out for in your next pcb: Power and ground planes are essential for ensuring stable power distribution and reducing noise, but designers sometimes forget to include them in their schematics or improperly implement them. This oversight can lead to power delivery issues, EMI problems, and signal integrity degradation. To avoid these issues, it is important for designers to use recommended layer stacks and follow proper decoupling capacitor placement.
Insufficient clearance between components can cause problems during assembly, particularly if the parts overhang the edge of the board. These edges can be nicked during handling, which may result in defective connections or the need for repairs. A thorough Design for Manufacturability check by your manufacturer will usually catch these oversights.
What are the common design flaws to watch out for in PCBs?
When designing a PCB, you should always consider the thermal management of all components, especially those with high operating temperatures. Insufficient heat dissipation can lead to premature component failure and degraded performance. To mitigate this issue, you should incorporate sufficient thermal padding to assist in heat transfer.
Inadequate clearance between pads and traces can lead to poor solder connection and signal degradation. This can also prevent the proper reflow of the solder and reduce the life cycle of your components. To avoid this problem, you should ensure that a minimum of 4 mils is between adjacent pad centers and traces.
Acute angles in traces can trap acid during the etching process, causing it to eat away more than is necessary. This can damage a trace, which can lead to intermittent failures or complete circuit failure. To eliminate this problem, you should avoid acute angles in your traces, and use rounded corners where possible.
Traces that are too narrow to accommodate the current needed for a circuit can burn through and cause shorts or loss of function. To avoid this, you should carefully calculate the required width for each trace and verify that it is correctly configured in your CAD software. You should also work closely with your manufacturers to ensure that your layerstacks and panelizations are compatible with their manufacturing processes.
A gap between a copper pour and the surface of the substrate is known as a “dry hole.” These gaps can allow moisture to penetrate the PCB, which may damage or destroy components. To avoid this, you should use the appropriate copper thickness for your application and avoid gaps at the edge of your boards.
Fortunately, there are many resources available to help you identify and correct these common PCB design flaws. You can turn to PCB contract manufacturers for engineering and design services as well as technical support and manufacturing expertise. They can also help you address EMC and EMI concerns in your design, if these issues are noted during the prototyping phase.
