Every electronic device tends to generate an electromagnetic field. With the increasing number of devices like TV, washing machines, traffic lights, electronic gadgets, etc., the radiations emitted from each of them are at risk of interfering with each other.
For this reason, the concept of Electromagnetic Compatibility (EMC) came into the picture to control the radiated and conducted Electromagnetic Interference (EMI). EMC is the ability of different electronic devices and components to keep functioning properly in other devices emitting electromagnetic waves. In simple terms, it is the establishment of compatibility within all the devices, so they don’t interfere with each other.
It is important to note that the EM waves or disturbances emitted by any electronic equipment should be maintained up to a certain level. Each device should possess enough immunity to withstand the EM disturbances that are prevalent in its surroundings. Otherwise, it can damage your equipment and can also set false triggers. A poorly designed EMC and the related EMI affects the PCBs (printed circuit boards) badly and has become a problematic area for the design engineers to deal with today. This is majorly due to the shrinking board designs and manufacturers demanding high-speed systems. With a widely pervasive electromagnetic environment, the only goal for a PBC designer is to minimize the interfering effects. Here are some amazing tips to help you in reducing the possibilities of any problematic issues in your PCBs –
Design an effective ground
The most crucial step in EMI shielding is to connect each component to a ground point, which will be responsible for neutralizing the effect of the electromagnetic field. It would help if you worked on increasing the ground area of PCB to reduce all sorts of emissions, crosstalk, and noises. However, using unnecessary ground planes can be a costly affair as it increases the PCB fabrication cost. So, to get it right in terms of functioning and the costs, you can resort to the splitting of ground planes at different places and accommodate multiple sections in one common ground layer.
Separate the analog and digital circuitry
Each of these circuitry comprises unique characteristics – the digital signal needs a digital ground, and the analog signal needs an analog ground. Analog circuits carry relatively high current and should be kept away from the switching signals. If required, you can guard them with a ground signal; otherwise, their digital circuitry interference will weaken the signal and deteriorate it. A good EMC is designed in such a way that it focuses on analog and digital circuitry separately. A low pass filter is also used to suppress or eliminate the noise from the surroundings and permit a stable current flow.
Correct placement of traces
Placing the traces and other components at 90-degree angles is a big no-no if you want to become successful in reducing EMI. They should be routed on the corners at 45-degree angles to keep the EMI negligible. It is indeed the duty of the manufacturer and importer of electronic goods to ensure their electromagnetic compatibility. But the government also should adopt more stringent laws so that no problems happen.