Noise Suppression Basic Course

Noise Suppression Basic Course Section 1

For engineers who are involved in noise suppresion basic contents are compiled to understand noise suppresion with suppresion filter (EMIFIL ^®).

Noise Suppression Basic Course Section 2

In Section 2, we will explain practical approaches and methods of noise suppression, deciding on themes as we proceed.

Noise Suppression Basic Course [Section 1]

Chapter 1

Reasons for requiring EMI suppression filters (EMIFIL ^® )

Chapter 1 describes the reasons for using EMI suppression filters (EMIFIL ^® ), and explains how shields and filters used for electromagnetic noise suppression work.

[Average time required for reading: approx.12 mins]

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Chapter 2

Mechanism of Causing Electromagnetic Noise

In order to have a deep understanding of the mechanism of noise interference, Chapter 2 focuses on the issues regarding the noise source side and describes the mechanism of noise occurrence such as how the noise occurs and where it occurs in the electric circuit.

[Average time required for reading: approx.47 mins]

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Chapter 3

Factors of making noise problems complex

In order to handle the noise interference for electronic devices, you need to understand not only the noise source origin, but also the characteristics of the transmission paths and antennas. Among these topics, Chapter 3 describes noise transmission paths.

[Average time required for reading: approx.50 mins]

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Chapter 4

Spatial conduction and its countermeasures

Many of the electromagnetic noise interferences are transmitted through space via radio waves. Chapter 4 describes the spatial conduction of noise. The chapter first discusses the interference between circuits (problem of short distance) and then describes the antenna theory (problem of long distance) and shielding to block this problem.

[Average time required for reading: approx.57 mins]

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Chapter 5

Conductor conduction and common mode

Chapter 5 first describes the existence of two modes (common mode and normal mode) for noise to be transmitted through a conductor and then describes the conversion into common mode.

[Average time required for reading: approx.49 mins]

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Chapter 6

EMI suppression filters

Chapter 6 describes the typical filter configuration used in noise suppression and how the actual characteristics of electronic parts used affect noise suppression results.

[Average time required for reading: approx.55 mins]

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Noise Suppression Basic Course [Section 2]

Noise suppression in digital signal lines

Theme 1

Proper Use of Noise Suppression Products for Digital Circuits

To resolve the problem of noise inflicted onto radios, TVs, and other devices by digital devices, EMI suppression filters have become widely used. This theme provides examples of the proper use of typical EMI suppression filters: capacitors, resistors, and ferrite beads. Also, this theme explains the reason why the noise suppression effect varies among sets.

[Average time required for reading: approx.21 mins]

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Theme 2

How to Select Ferrite Beads Considering the Characteristics of Digital Circuits

Radiation noise and other noise increase with the acceleration of the signal speed of digital signal lines. If the amplitude of the signal voltage is lowered to accelerate the signal speed, ringing of the signal waveform becomes a problem. This theme describes the changes in the waveform and radiation noise when a resistor is added to a standard logic IC and impedance matching is performed, as well as how to select ferrite beads for signal lines for which impedance matching has been performed.

[Average time required for reading: approx.8 mins]

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Theme 3

Noise Suppression in Differential Transmission

Differential transmission is widely utilized for high-speed signal lines of noise countermeasures of recent electronic devices. This theme explains the reason for this, the noise that should be taken into consideration in the differential transmission line, and the suppression methods for the noise. This theme also explains the basis of the mixed S parameter, which represents the transmission characteristics of the differential transmission line, and the effect of these characteristics.

[Average time required for reading: approx.13 mins]

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