What is EMC?


It is important not to influence nor be influenced by other electronics devices.

EMV DEFINITION: EMC is defined as the ability of devices and systems to operate in their electromagnetic environment without impairing their functions and without faults and vice versa.
Electromagnetic compatibility, EMC ensures that operation does not influence the electromagnetic environment to the extent that the functions of other devices and systems are adversely affected.


The aim of employing EMC measures is to ensure that a variety of different items of electronics equipment can operate in close proximity without causing any undue interference.


The interference that gives rise to impaired performance is known as Electromagnetic Interference, EMI. It is this interference that needs to be reduced to ensure that various items of electrical equipment are compatible and can operate in the presence of each other.



There are two main elements to EMC:


EMISSIONS: The EMI emissions refer to the generation of unwanted electromagnetic energy. These need to be reduced below certain acceptable limits to ensure they do not cause any disruption to other equipment.


SUSCEPTIBILITY & IMMUNITY: The susceptibility of an item of electronics to EMI is the way it reacts to unwanted electromagnetic energy. The aim of the design of the circuit is to ensure a sufficiently high level of immunity to these unwanted signals.


Entering the broadband age, we are using conveniently personal media as cellular phone, PDA and notebook PC, etc., while our electromagnetic environment getting worst. Hence, the EMC solution for compatibility of electromagnetic and electronic devices becomes increasingly important.


Noise solution techniques is basically divided into 3 methods; grounding, shielding and filtering. These are fundamental noise solution techniques applicable also to the electric devices which applies a frequency wave 1GHz or more.


For those above mentioned 3 methods, we are offering a lot of technical products and solutions.





There are two main EMC problems:


  • EMI (Electromagnetic Interference), suppress the emission of electromagnetic waves (Emission).
  • EMS (Electromagnetic Susceptibility), prevent malfunction caused by unwanted noise from other equipment (Immunity).


Basic policy of EMC is to satisfy both requirements.


Eliminate the cause of noise emission by eliminating the voltage difference by connecting the GND of PCB with metal chassis that is the reference potential.

Better noise reduction is achieved by multipoint and correct position of grounding.


Countermeasures against specific frequencies: conversion of absorbed noise into heat or other energy, and separation of unwanted noise from necessary noise.

Magnetic flux, which is generated by the electric current is absorbed into ferrite core by its permeability μ’ and it is converted into thermal energy.


By shielding, prevent noise from radiating to outside and from being influenced by the noise outside.