Dianne Pajo https://www.deepcoat.com 2m 436 #emishielding
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One thing that PCB designs can’t underestimate or overlook is EMI and EMI shielding. Below, we’ll explain the basics of EMI and what PCB designers must know about EMI shielding to build a functional PCB.
What Is Electromagnetic Interference (EMI)?
First, PCB designers can’t understand how to protect their PCBs from EMI if they don’t understand what it is. EMI is when the source of one signal interrupts another and causes signal disruption or failure.
The close relationship between electricity and gravity means all electrical flow in electronics creates a small gravitational field. This field and signal can damage sensitive circuits through induction or electrostatic coupling. EMI can come from natural sources like lightning or solar flares but is more commonly produced from human-made wireless devices and electronic appliances.
Why Is EMI Shielding Important in PCB Design?
As every PCB designer knows, PCBs contain many sensitive circuits that, if disrupted, can cause the entire design to fail. And as we all know, modern life is filled with wireless and electronic devices, and all of these devices produce strong signals and the potential for EMI.
Naturally, PCB designers must consider EMI when planning and building their PCB. To protect their PCB from EMI, it’s critical that PCB designers consider EMI shielding.
How Does EMI Shielding Work?
Before planning and building their PCB, PCB designers need to know the basics of EMI shielding, including how it works and the ideal materials for its applications. EMI shielding is when a critical PCB circuit is covered with a metal shield to absorb radiation and EMI.
This metal shield is critical for absorbing interfering signals and EMI and protecting the circuits, but PCB designers have to consider the material they use for this shield.
What Materials Are Best for PCB EMI Shielding?
To create an effective EMI shield for a PCB, the sensitive circuits must be completely encapsulated on all sides to create a stable layer of material to absorb the EMI, which then connects to the ground plane and disseminates the EMI. The material most often used in PCB EMI shielding is copper because it’s the most reliable material for reducing magnetic and electrical waves.
Some PCB designers also use shielding films to cover awkward corners and odd shapes when needed. Silver ink shields, which are printed shields that conduct electricity, are also advantageous due to their flexibility and ability to bond to many media, such as plastics and composite materials.
If you’re designing a PCB, you can’t underestimate how essential a capable EMI shield is to ensure the design is effective.