The working environment of the multilayer pcb will be subject to different external interferences. These interferences may be interference from the power supply, interference from the space electromagnetic field, and interference from the ground wire. So, what are the measures to suppress interference on the electronic board?
1. Filtering: A filter is a network composed of resistance, inductance and capacitance with lumped or distributed parameters, used to separate the noise superimposed on the useful signal. The filter has a good effect on suppressing the transient noise of the inductive load. After the filter is connected to the input end of the power supply, the electromagnetic interference from the power grid can be reduced.
2. Shielding: Shielding refers to the absorption or reflection of external electromagnetic interference by various shielding objects to prevent noise from intruding; or on the contrary, limiting the electromagnetic energy radiated inside the device to the inside of the device to prevent interference with other devices.
3. Reasonable wiring: The type of wire, the thickness of the wire diameter, the way of routing, the distance between the wires, the length of the wire, the binding or twisting, the shielding method, and the symmetry of the wiring all affect the inductance, resistance and The coupling of noise has a direct effect.
4. Grounding design: Many radio frequency electronic equipment and systems contain a variety of circuits, Electronic components, components and devices, and their nature is complex and diverse. It is necessary to divide the grounding lines of circuits and structural parts at all levels into signal ground, control ground, power ground and Safety grounding, etc.
5. Isolation: Taking potential isolation or spatial isolation measures is an effective way to prevent external interference for related circuits with very different levels.
6. Others: circuit decoupling, impedance matching, and anti-static of electronic logic devices are all components of anti-interference technology.