PCB signal integrity (SI) requirements ensure signals travel without distortion or interference. Here are some key requirements that help ensure that high-speed signals remain clear and reliable.

Maintain consistent trace width and spacing to avoid signal loss or reflection.

Ensure traces are properly spaced to reduce interference (crosstalk) and keep trace lengths equal for critical signals.

Increase the distance between traces or add ground traces between them to prevent interference.

Use a dedicated ground layer to improve signal quality and reduce noise.

Too many vias (holes in the board) can affect signal quality, so keep them to a minimum.

Route paired signals close together and keep their lengths the same for better signal integrity.

Use decoupling capacitors and good power plane design to reduce noise in the power system.

Use termination resistors to match the signal path impedance and reduce signal bouncing.

Don't create unnecessary branch traces, as they can degrade signal quality.

Reduce loop areas, route signals carefully, and use shielding to minimize electromagnetic interference.

Keep signals in sync by ensuring uniform trace lengths.

Select materials that minimize signal loss, especially in high-speed designs.

Achieving high-density routing on a PCB requires careful planning and design techniques to ensure that many components and connections can be accommodated without compromising performance. Here are some key design best practices to fit more components and connections on a PCB while maintaining performance.

Use thinner traces and smaller gaps to fit more connections on the board.

Add more layers to your PCB to increase space for routing signals.

Apply blind, buried, or microvias to save space and make routing easier between layers.

Place vias directly in component pads to save room for routing.

Use components with closely spaced pins to fit more parts in smaller spaces.

Use High-Density Interconnect (HDI) techniques like tiny vias and thin traces for compact, complex designs.

Keep paired signal traces close and consistent to maintain quality.

Place some components inside PCB layers to save surface space.

Place components close to each other to reduce the need for long traces.

Manage trace width and spacing for high-speed signals to avoid interference.

Use vias only when necessary to avoid taking up valuable routing space.

Plan your PCB layers carefully to organize signal, power, and ground traces efficiently.

For complex parts like BGAs, use escape routing to organize connections to other layers.

Use copper fills for power and ground to free up space for signal routing.