PCB Design Tutorial – How to Layout with High Quality

PCB circuit board is the basis of all electronic circuit design electronic components. As the main carrier to be equipped with all the components of the circuit. PCB is not only a combination of scattered components, but also to ensure the circuit design is clear and avoid the artificial mistake when connecting different wires.

1. Traces need to be in reasonable direction

Such as input/output, AC/DC, strong/weak signal, high frequency / low frequency, High/low voltage. Their direction should be linear (or separate) and not be crossed in order to mutual interference. The best direction is in straight line, but it is hard to achieve. The most unfavorable direction is in ring. For DC, small signal, low voltage PCB design, the requirements can be not very strict. Reasonable is relative.

2. Choose a good grounding

Grounding point has been mentioned too many times. Normally we require a total level point grounding such as: forward amplifier’s ground trace should be merged first then connect with the main ground. Sometimes it is hard to achieve because of some restriction. It is a flexible problem in practice. Every engineer has their own solution.

3. Reasonable layout power supply filter/decoupling capacitor

Generally we will arrange a few power filter/decoupling capacitors in schematic, but they are not indicated where they should be. These capacitors are used for switching devices(gate) or other components which need to be filtered/ decoupled. These capacitors should be close to these components when layout or it will has no effect. Also, when the power filter/decoupling capacitor layout is reasonable, the grounding point problem will be not serious.

4. Trace width should be appropriate with blind vias and through vias

If you can use width trace, never use fine trace. Trace for high voltage and high frequency should be smooth and doesn’t have angle. Ground wire should be wide as soon as possible, the best way is to use copper pour. If the pads and vias are too small, it will be hard to drill and cut the pads as ‘c’ or cut pads totally. If the traces are fine and no use in copper pour, the quality in etching traces will be worse. So the copper pour is not just used in ground but also help in production.

Quantity of vias and density of traces

Some problems cannot be found in the early stages of circuit production. They tend to emerge in the late, such as too many traces and vias, it is risky when etching the copper. So the design should be minimized with vias. If the parallel trace density is too large, it will be easy to solder them into a piece. So the trace density should be determined according to your solder processing ability. If the distance between the solder joints is too small, we need to take more time to ensure the solder quality.

If you get all the points above, please let Seeed Fusion Service to help you to manufacture the PCB.


August 2017