Component placement is one of the initial and most important stages of PCB designing. It must be done with utmost care in order to save time and avoid rework. Here are some tips to help the designer with effective component placement.
- Grouping and positioning of components: One of the most important tips is to group components with similar functions together as they generate the same amount of heat and other currents, and helps in maintaining temperature levels and avoiding any damage. For instance, PMICs, convertors, LDOs etc. can be grouped as a power management section. Then based on the group dynamics, the other sections can be placed. For example, the power supply section must be placed away from digital or analogue parts, and components that generate electromagnetic noise or radiation must be kept away from more sensitive signals, this helps increase the efficiency by allowing for better control of the return path. To increase the assembly process’s efficiency and reduce positioning errors, one must ensure that the ICs are all aligned in the same direction. A simple rule is to place all the components with similar functions in my direction. Another rule to keep in mind is the distance between sections and components. This prevents dangerous interference between the mixed signals. Also, make sure a space of at least 50mil is maintained between components. Another element that should be considered while placing the components is that components that handle high-speed signals must be grouped and placed at a short distance from each other to simplify the routing of the traces.
- Keeping components away from heat sources: It is always suggested to avoid placing other components close to power components that generate heat. For instance, MOSFETs, IGBTs, PMICs and voltage regulators generate a fair amount of heat, sometimes the rise in temperature can affect the functioning of other components. Therefore, try placing such components away from other components.
- Creating solid ground planes: The uniformity of the ground plane should always be maintained as they facilitate the onset of signal and power integrity issues. In any case, where maintaining uniformity isn’t possible, be extremely cautious when placing components across the interruption as that could cause an interruption of the return path for those signals and affect the functionality of the PCB. Also, avoid an excessive number of routes as that too could cause an interruption of the return path.
- Placement near the PCB edges: It is always advisable to place components that require screw fixing near the edges so as to avoid unwanted contact of cables with other components. In addition to that, make sure no component is placed too close to the edge, at least a gap of 100mil between each component and the edge of the board should be maintained.
- Enough space for the traces: With an increasing demand for compact-size portable technology, PCBs, too are required to be of the minimum dimensions. But, it is important to not be misled and to be aware that there is a limitation to the miniaturization of circuits. While designing your PCB, ensure it is of an optimal size where enough space is left to route all the traces.
- Thermal management: Lastly, the thermal management of the PCB is very important. Certain components generate a considerable amount of heat during their operation. If not placed properly, this could increase the overall temperature of the board and lead to burning or other damage. To avoid this situation, such components must be placed in the centre of the PCB. This helps in the thermal management of the PCB by evenly distributing the generated heat across the board.
We hope the above-suggested tips come in handy and help you fight out the common obstacles in building an efficient PCB. Gelco always seeks to present you with the best possible solutions and expert advice.