How Smart PCB Layout Choices Reduce Manufacturing Cost and Improve Yield
In electronics manufacturing, the cost of your PCB assembly (PCBA) isn’t defined solely by materials, components, or labour. A significant part of your total cost is influenced directly by how you design your board. Careful decisions around pad geometry, spacing, thermal relief, silkscreen placement and component proximity can dramatically impact yield, quality and throughput.
At NOTE, we work with designs from simple two‑layer boards through to complex 26‑layer HDI flex‑rigid assemblies. Across all this diversity, one principle is consistent:
Designing for manufacturability (DfM) is one of the fastest, most effective ways to reduce cost.
1. Pad Design: The Foundation of Reliable Assembly
Pad geometry plays a critical role in achieving stable solder joints. Poor pad design can cause misalignment, component movement during reflow, and increased rework.
Key considerations
- Follow manufacturer‑recommended pad shapes and dimensions.
- Use symmetrical pad designs to avoid differential heating.
- Avoid overly large pads, which can pull components during reflow.
Why this matters
Better pad design improves first‑time yield, reduces manual intervention and ensures consistent results across production runs.
2. Pad Gaps: Precision That Reduces Defects
Fine‑pitch components such as 0201 parts demand accurate pad spacing. Even small variations can cause soldering issues, including tombstoning.
Best practice
- Aim for a 0.2 mm pad‑to‑pad gap, or slightly less depending on the footprint.
- Review CAD library settings to ensure defaults match your manufacturing needs.
Result
A more stable solder fillet and improved reflow consistency across all miniature components.
3. Thermal Relief: Balanced Heating for Better Reflow
Uneven heat distribution between pads is one of the most common causes of tombstoning. Proper thermal relief design ensures pads heat at similar rates.
Design guidelines
- Include thermal relief patterns when connecting pads to copper pours.
- Avoid overly large spokes or large copper connections that soak heat excessively.
- Manually adjust thermal relief for compact or intricate areas where automation may be insufficient.
Outcome
Consistent heating, fewer lifted components and higher overall yield.
4. Silkscreen Placement: Preventing Lift and Misalignment
Silkscreen printed beneath components — particularly DFNs, QFNs and leadless devices — can prevent them from sitting flat on the PCB surface.
Checklist
- Remove silkscreen from beneath all leadless packages.
- Keep reference designators away from pads and solderable surfaces.
- Review automated silkscreen placement rules in your CAD tool.
Benefit
Better coplanarity, improved solder joint integrity and fewer placement‑related defects.
5. Component Proximity: Designing for Automated Soldering
Selective soldering systems offer excellent repeatability, but only when components are placed with adequate spacing to avoid interference.
Recommended spacing
- Maintain at least 3 mm between SMD and through‑hole components when selective soldering is required.
- Position SMD components away from board edges to allow nozzle access.
- Group similar component types where possible for more efficient processing.
Impact on cost
Improved accessibility reduces manual soldering, lowers rework time and supports faster throughput.
Summary: Top Six Cost‑Saving PCB Design Principles
- Follow correct pad design recommendations
- Set accurate pad gaps for fine‑pitch parts
- Maintain consistent pad sizes
- Apply effective thermal relief patterns
- Avoid silkscreen under leadless components
- Ensure correct spacing for selective soldering
Conclusion: Better Designs Lead to Lower Costs
The most cost‑efficient PCBA designs emerge when layout engineers and manufacturing teams collaborate early in the design phase. Addressing key factors — pad geometry, spacing, thermal relief, silkscreen placement and component proximity — at the outset prevents costly redesigns and reduces rework.
The result is clear:
Better yield, greater reliability, faster turnaround, and lower overall manufacturing cost.