Firstly, consider the PCB size. When the PCB is too large, the printed lines become longer, increasing impedance, reducing noise immunity, and also raising costs; conversely, a PCB that's too small has poor heat dissipation and nearby lines are prone to interference. After determining the PCB size, proceed to place special components. Layout all circuit components based on the functional units of the circuit. When positioning special components, adhere to the following principles: (1) Minimize the connections between high-frequency components to reduce their distributed parameters and electromagnetic interference. Components susceptible to interference should not be placed too close together, with input and output components kept as far apart as possible. (2) There may be high potential differences between certain components or wires; increase the distance between them to prevent accidental short circuits due to discharge. High-voltage components should be placed where they are not easily accessible during debugging. (3) Components weighing more than 15g should be secured with brackets before being soldered. Large, heavy, and high-heat-generating components are not suitable for placement on the PCB and should be mounted on the main chassis bottom plate, with heat dissipation considerations. Heat-sensitive components should be kept away from heat-generating components. (4) The layout of adjustable components like potentiometers, variable inductors, variable capacitors, and microswitches should consider the overall structure of the unit. For internal adjustments, they should be placed on the PCB for ease of adjustment; for external adjustments, their position should correspond to the position of the adjustment knobs on the chassis front panel. (5) Allow space for the PCB mounting holes and the area occupied by the fixed brackets. Aeronautical Power
When arranging all components of a circuit based on its functional units, adhere to the following principles: (1) Position the functional circuit units according to the circuit's flow, making the layout conducive to signal flow and maintaining a consistent direction of the signals as much as possible. (2) Center the layout around the core component of each functional circuit. Components should be evenly, neatly, and compactly arranged on the PCB, with an effort to minimize and shorten the leads and connections between components. (3) For circuits operating at high frequencies, consider the distributed parameters between components. Generally, components should be arranged parallelly as much as possible, which not only enhances aesthetics but also facilitates assembly and soldering, making mass production easier. (4) Components located at the edge of a high-power DC stabilizing power supply circuit board should be at least 2mm away from the edge of the board. The shape of the high-power DC stabilizing power supply circuit board is rectangular, with a length-to-width ratio of 3:2 or 4:3. The surface dimensions of the high-power DC stabilizing power supply circuit board are greater than 200At 150mm, consider the mechanical strength of the circuit board for high-power DC stabilizing power supply. 36V aviation power supply.
