Designing for Minimal EMI
Designers of today’s smartphones, tablets and PCs are constantly balancing the constraints of small space to package components and increasing noise sensitivity. The difficulty in designing these products is compounded when trying to get the most from low level signals like those used to power an antenna while still protecting against incoming noise and noise emissions by meeting the strict requirements of electromagnetic interference (EMI) and radio frequency interference (RFI) regulations.
Electronic device designers normally choose clean lines and sharp edges to optimize the performance and improve harmonics of the system. Unfortunately these design elements also lend themselves to radiation around the periphery. Signal paths may become antennas and right angles help to radiate energy out of the circuit.
Designers have been given some help in designing around increasing frequencies with decreasing voltage levels in the logic of their systems. Now that voltage levels in modern logic have decreased from 12v to 3.3v and 1.8v engineers can design systems that control radiated power better – radiation is directly related to the voltage level of the circuit. Of course, lower voltage levels also mean the signal’s strength is lower and is more easily influenced by noise levels and interference from local and external sources.
How Shielding Helps EMI in Electronic Devices
EMI Shielding can help block electromagnetic energy from being reflected, directed or absorbed within or out from a circuit board. Faraday first demonstrated this principle with solid shielding and the Faraday cage still represents the best design technique to shield components. However, the real world requires that shielding has holes to allow for inputs and outputs like incoming power to the board and outgoing signals to other components.
Solid enclosures are ideal to reduce EMI and RF from a circuit’s signals to penetrate or radiate from a device and the closer these enclosures are to the circuit, the better they perform. For this reason, Faspro Technologies designs board level shielding in various sizes and shapes or custom designed solutions to fit any need. These sheilds are soldered to the board with vents to allow gases to be expelled from within the shielded zone during soldering.
Faspro Technologies is a leader in solving the demanding problems in consumer electronics, medical, telecommunications, industrial, aerospace, and automotive applications.
For more information on how Faspro Technologies designs and builds effective EMI shielding for medical devices, please Contact Us or fill in the form below.