PCB Board Design Considerations

This Gold Phoenix PCB Knowledge Center article explains that designing circuits is challenging work that electronic engineers must master. If the design is unreasonable, the performance will be greatly reduced, and the circuit may not function properly. This article covers the key precautions in PCB board design.

1. Create a Physical Border

The closed physical frame is very important for future component layout and routing and must be accurate; otherwise, there will be installation problems later. It is best to use arcs at corners — on one hand, this can avoid sharp corners injuring workers, and at the same time it reduces stress.

2. Layout of Components

The layout and routing of components have a great influence on the quality of the product, and the following principles should be followed:

(1) Placement Order

First, place the components related to fixed structural positions, such as power sockets, indicator lights, switches, and connectors. Then, place special components and large components, such as heating components, transformers, and ICs. Finally, place the small devices.

(2) Pay Attention to Heat Dissipation

For high-power circuits, heating elements should be dispersed as far as possible to facilitate heat dissipation and not concentrated in one place.

3. Reasonable Wiring

The following routing principles should be followed:

1. High-frequency digital circuit traces should be as thin and short as possible.

2. Isolation should be maintained between large current signals, high voltage signals, and small signals.

3. When wiring with double-sided boards, the wires on both sides should be perpendicular to each other, oblique, or curved to avoid being parallel, in order to reduce parasitic coupling.

4. The routing angle should be greater than 90 degrees as much as possible, with 135° being the preferred angle. Corners below 90 degrees should be eliminated.

5. The same address line or data line should not have too large a difference in trace length.

6. Route traces on the soldering surface as much as possible. Use as few vias and jumpers as possible.

7. Components and traces should not be placed too far apart.

8. The convenience of production, debugging, and maintenance must be considered.

4. Adjust and Improve

Once the wiring is complete, adjustments should be made to the text, individual components, traces, and copper pour. If copper is used instead of the ground wire, it is important to ensure that the entire ground is connected, verify the magnitude and flow direction of the current, and check for any special requirements to minimize unnecessary errors.

5. Check the Network

Sometimes the network relationship drawn in the layout differs from the schematic due to negligence, and it is necessary to verify and correct any discrepancies.