In PCB design, we often encounter a variety of PCB special components, and the layout of these special components also has many considerations. Today, we will introduce how to layout PCB special components!
PCB special components refer to key components in the high-frequency part, core components in the circuit, easily disturbed components, high-voltage components, high calorific value components, and some heterosexual components. It is necessary to carefully analyze the position of these special components to ensure that the belt layout meets the circuit functions and production requirements. Improper placement may lead to circuit compatibility and signal integrity issues, resulting in PCB design failure.
When designing and placing special components, the first consideration is the size of the PCB. When the PCB size is too large, the printing line becomes too long, the impedance increases, the dry resistance decreases, and the cost increases; If it is too small, the heat dissipation is not good, and adjacent lines are prone to interference. After determining the PCB size, determine the square position of the special components. Finally, arrange all components of the circuit according to their functional units. The position of special components should generally follow the following principles when arranging:
1. Try to shorten the connection between high-frequency components and minimize their distribution parameters and electromagnetic interference with each other. Components that are susceptible to interference should not be placed too close together, and inputs and outputs should be as far apart as possible.
2.Some components or wires may have high potential differences, so the distance between them should be increased to avoid accidental short circuits caused by discharge. High voltage components should be kept out of reach as much as possible.
3.Components weighing over 15g can be fixed with brackets and then welded. These heavy and high heat generating components should not be placed on the circuit board, but on the bottom plate of the main box, and heat dissipation should be considered. Hot parts should be kept away from heating components.
4.For the layout of adjustable components such as potentiometers, adjustable inductance coils, variable capacitors, and microswitches, the overall structural requirements should be considered. If the structure allows, some commonly used switches should be placed in positions that are easily accessible by hand. The layout of components should be balanced, dense, and not heavier than the top.
