On the premise of meeting circuit performance standards, the arrangement of components must also be considered to be neat, aesthetically pleasing, and easy to test. The mechanical dimensions of the board and the positioning of the sockets must be thoughtfully evaluated.
A well-planned component layout is a fundamental prerequisite for creating high-quality PCB designs. The requirements for component arrangement primarily encompass installation, mechanical stress, thermal considerations, signal integrity, and aesthetic appeal.
1. Installation
This refers to a set of guidelines established to ensure the smooth installation of the circuit board into the chassis, enclosure, or slot, without interference, short circuits, or other issues. It is also essential for designated connectors to be positioned correctly within the chassis or enclosure according to specific application scenarios.
2. Mechanical Stress
The circuit board should be capable of withstanding various external forces and vibrations during installation and operation. To achieve this, the board must have an appropriate shape, and the locations of all holes (such as screw holes and custom-shaped holes) should be strategically arranged. Generally, the distance from the hole to the edge of the board should exceed the diameter of the hole. Additionally, care must be taken to ensure that the weakest section of the board, resulting from any custom-shaped holes, possesses adequate bending strength. Connectors that extend directly from the device enclosure on the board must be securely fixed to guarantee long-term reliability.
3. Thermal Considerations
For high-power devices that generate significant heat, it is crucial to not only ensure effective heat dissipation but also to position them appropriately. This is particularly important in sophisticated analog systems, where attention must be given to the potential adverse effects of the temperature field created by these devices on delicate preamplifier circuits. Typically, components that draw substantial power should be housed in separate modules, with appropriate thermal isolation measures implemented between the signal processing circuit and other circuits.
4. Signal
Signal interference is a critical factor to consider in PCB layout design. The fundamental principles include: separating or even isolating weak signal circuits from strong signal circuits; keeping AC components distinct from DC components; separating high-frequency circuits from low-frequency circuits; paying attention to the orientation of signal traces; designing ground layouts effectively; and implementing proper shielding and filtering measures. These points have been extensively discussed in numerous publications, so I won’t reiterate them here.
5. Aesthetics
In PCB design and layout, it is essential to consider not only the neat and orderly arrangement of components but also the aesthetic and smooth routing of traces. While laypersons may often emphasize the former to evaluate circuit design quality, the visual aspect should take precedence when performance requirements are not stringent. However, in high-performance scenarios—especially when using double-sided boards that may be encapsulated and generally out of sight—the aesthetic quality of the routing should be prioritized.
If you have any PCB manufacturing needs, please do not hesitate to contact me.Contact me