Industrial control motherboard: How to deal with electromagnetic interference?

As the core component of various industrial equipment, the industrial control motherboard plays a crucial role. In practical work, due to the existence of electromagnetic interference problems, the stability and reliability of the motherboard are greatly challenged. Therefore, how to deal with electromagnetic interference is one of the key points in the design and maintenance of industrial control motherboards. This article will introduce some methods and technologies to reduce electromagnetic interference.

electromagnetic shielding

Electromagnetic shielding is one of the effective means to solve the problem of electromagnetic interference. It prevents the propagation and interference of electromagnetic waves by using special materials and structures. For example, adding a metal shielding cover around the shell of the motherboard can effectively shield external electromagnetic noise. In addition, shielding covers can be added around sensitive devices and signal lines to protect them from electromagnetic interference.

Ground wire design

Correct ground wire design can effectively eliminate electromagnetic interference. All ground wires of the motherboard should be connected to a separate ground plane and should be as close to the power supply as possible to form the shortest secondary circuit. This will help reduce the inductance and resistance of the ground wire, thereby improving the quality and anti-interference ability of the signal.

Filter design

Adding filters to the motherboard is another effective way to reduce electromagnetic interference. Both the input and output terminals can use filters for filtering to eliminate power noise and radiated interference. These filters are typically constructed using components such as capacitors, inductors, and transformers, and different filtering types can be selected, such as low-pass, bandpass, or high-pass.

Line layout

A reasonable line layout is one of the keys to reducing electromagnetic interference. Analog signal lines and digital signal lines should be separated as much as possible, and the lines of sensitive devices should be as short as possible. In addition, for signal lines with different frequencies, staggered or planar layouts can also be used to reduce crosstalk and mutual interference.

Grounding technology

The correct grounding technology is also one of the keys to solving electromagnetic interference problems. All signal ground wires and power ground wires should be connected to a central location and ensure that the ground wire potential is not greater than 0.05V. In addition, in practical work, the principle of "single point grounding" should also be followed, which is to minimize the number and length of ground wires as much as possible.

In short, electromagnetic interference is one of the important factors affecting the reliability and stability of industrial control motherboards. In order to ensure the normal operation of the motherboard, a series of effective technologies and methods need to be adopted to reduce electromagnetic interference. These methods include electromagnetic shielding, ground wire design, Filter design, line layout and grounding technology. In actual design and maintenance, the most suitable method should be selected based on the specific situation and strictly implemented.