We are offering Surge Protectors. Most electrical and electronic devices can generate andor be affected by EMI. Sources are everywhere and include ac motors, fluorescent bulbsballasts, light dimmers, microwave ovens, microprocessors, computers, and switch-mode power supplies.
Within switch-mode power supplies, a high dc voltage is chopped or switched at a high frequency that can range from 50 kHz to 1 MHz. This high-speed switching process is intrinsic to switch-mode power supplies and provides its improved efficiency and reduced size when compared to linear power supplies.
However, as a side effect, this switching generates unwanted EMI. In fact, most conducted EMI within switch-mode power supplies originates from the main switching MOSFETs, transistors, and output rectifiers.
In either power supplies or electronic equipment, it is the function of the EMI filter to keep any internally generated noise contained within the device and to prevent any external ac line noise from entering the device. EMI filters usually comprise a network of passive electronic components including capacitors and inductors that form L-C circuits.
Since unwanted EMI is at much higher frequencies than normal signals, the EMI filter works by selectively blocking or shunting unwanted higher frequencies. Basically, the inductive part of the EMI filter is designed to act as a low-frequency pass device for the ac line frequencies and a high-frequency blocking device.
Other parts of the EMI filter use capacitors to bypass or shunt unwanted high-frequency noise away from the sensitive circuits. The net result is that the EMI filter significantly reduces or attenuates any unwanted noise signals from entering or leaving the protected electronic device.

We are offering Surge Protectors. Most electrical and electronic devices can generate andor be affected by EMI. Sources are everywhere and include ac motors, fluorescent bulbsballasts, light dimmers, microwave ovens, microprocessors, computers, and switch-mode power supplies.
Within switch-mode power supplies, a high dc voltage is chopped or switched at a high frequency that can range from 50 kHz to 1 MHz. This high-speed switching process is intrinsic to switch-mode power supplies and provides its improved efficiency and reduced size when compared to linear power supplies.
However, as a side effect, this switching generates unwanted EMI. In fact, most conducted EMI within switch-mode power supplies originates from the main switching MOSFETs, transistors, and output rectifiers.
In either power supplies or electronic equipment, it is the function of the EMI filter to keep any internally generated noise contained within the device and to prevent any external ac line noise from entering the device. EMI filters usually comprise a network of passive electronic components including capacitors and inductors that form L-C circuits.
Since unwanted EMI is at much higher frequencies than normal signals, the EMI filter works by selectively blocking or shunting unwanted higher frequencies. Basically, the inductive part of the EMI filter is designed to act as a low-frequency pass device for the ac line frequencies and a high-frequency blocking device.
Other parts of the EMI filter use capacitors to bypass or shunt unwanted high-frequency noise away from the sensitive circuits. The net result is that the EMI filter significantly reduces or attenuates any unwanted noise signals from entering or leaving the protected electronic device.