Contact Us

TEL: +86-755-26664885
Fax: +86-755-27898086
E-mail: sales@wellspcba.com
Address: 3/F, Yinjin Industrial Park, Liuxian 2 Road, Bao'an District, Shenzhen, Guangdong, China

Home > Blog > Content
PCB circuit board anti-jamming design should follow what rules?
Mar 30, 2018

During the operation of a PCB circuit board, the circuit board cannot be normally operated due to various interferences. The main source of these interferences is the effect of the current. Therefore, when designing the circuit board, it is necessary to pay relatively attention to the current. Layout, design, and other related situations.

 

In the circuit board layout, the first thing we need to consider is the size of the circuit board. If the size is relatively large, the printed lines are long. As a result, the resistance increases, and the ability to resist interference decreases. Therefore, it will lead to poor heat dissipation of the circuit board, and the adjacent lines are susceptible to interference. In the case of determining the size of the circuit board, we need to determine the location of special components. Finally, we can eliminate the circuit's function. To lay out a circuit board reasonably, generally follow the following rules.

1. To reduce the connection between high-frequency components as much as possible, by this method to reduce the distribution parameters between them and the electromagnetic interference between them, for those components that are more easily interfered with each other can not be obtained Too close, input and output components should be as far away as possible.

 

2. There may be a high potential difference between certain components or wires on the device, and the distance between them should be increased appropriately to avoid accidental short circuit due to discharge. Components with high voltage should be placed as close to the hand as possible during commissioning.

 

3. For components weighing more than 15g, they should be fixed with brackets and then welded. Those components that are large, heavy, and have a lot of heat should not be mounted on printed boards, but should be mounted on the chassis of the entire chassis, and heat dissipation should be considered. The thermal element should be far from the heating element.

 

4. The layout of potentiometers, adjustable inductors, variable capacitors, microswitches and other adjustable components should consider the structural requirements of the entire machine. If the adjustment inside the machine, should be placed on the printed circuit board to facilitate the adjustment; if the adjustment outside the machine, its position and the adjustment knob on the chassis panel to adapt to the location.

 

5. For devices with weak noise immunity and large changes in power supply during shutdown, such as RAM and ROM memory devices, directly connect the tantalum capacitor between the power line and the ground of the chip.

 

6. Power line design According to the size of the printed circuit board current, try to increase the width of the power cord to reduce loop resistance. At the same time, the direction of power lines and ground lines and the direction of data transfer are the same, which helps to enhance anti-noise capability.

 

7. The grounding wire should be as thick as possible. If the grounding wire uses a very thrilling line, the grounding potential changes with the change of the current, so that the anti-noise performance is reduced. Therefore, the ground wire should be thickened so that it can pass three times the response current of the printed board. If possible, the grounding wire should be 2~3mm above.

 

How the PCB circuit board anti-jamming needs is to consider the problem from many aspects, the above introduction is just a brief introduction of some common anti-jamming operation, in the actual operation requires a combination of personal experience and function To achieve anti-jamming operation.

图片9.jpg

Previous: How to solve the distortion of PCB PCB?

Next: How to set the SMT patch processing quality control point?