No photo EMC ( electromagnetic compatibility ) specification designed electronic devices during the operation will produce electromagnetic radiation may affect their normal work, and interference from nearby electrical appliances.
EMC electromagnetic interference (EMI), electromagnetic fields (EMF) and radio frequency interference (RFI) and so provides the maximum limits. This requirement ensures the proper functioning of electrical appliances and other nearby .
EMC on a device , the scattering or energy transfer to another device , there are strict limits , and to reduce external to EMF, EMI, RFI and other requirements of the design when the magnetic susceptibility .
In other words , EMC regulations aim is, to control electromagnetic radiation within a certain range. However , in theory , this is a very difficult problem , most real-world applications through the use of power and ground layers , or the PCB into the metal box in which to address these issues . Power and ground layers to prevent signal interference layer , metal box utility is similar, can play a role in shielding .
The maximum speed of the circuit according to EMC requirements have to look at how to do it. Internal EMI, such as current consumption conductors , will be enhanced as the frequency increases . If the current gap between the two is too large , so be sure to lengthen the distance between the two. It also tells us how to avoid the pressure, and to allow the circuit to minimize current consumption . Wiring delay rate is also important , the length of the natural short as possible. So good wiring small PCB, would be more suitable for operation at high speeds than the big PCB.
