Design for Manufacturability (DFM) plays a crucial role in PCB assembly by optimising the design of the circuit board for efficient and cost-effective manufacturing. By considering manufacturability factors during the design phase, such as component placement, trace routing, and material selection, DFM ensures that the PCB can be produced with minimal defects, reduced production time, and lower costs. It helps prevent common manufacturing issues like soldering defects and component misalignment, ultimately leading to higher-quality PCBs and improved overall product performance.
Benefits of DFM:
- Higher product quality: DFM enhances product quality by minimising the need for design modifications during PCB manufacturing, which can otherwise compromise quality.
- Time to market reduction: The manufacturing process consists of multiple stages, each prone to potential errors. DFM minimises delays resulting from defective products, errors, and the time spent on project reviews and documentation checks.
- Cost reduction: DFM empowers PCB designers to create boards that can be efficiently produced even at high volumes. Reduced costs are a result of fewer errors detected during the PCB manufacturing process.
Common DFM issues to avoid in your PCB design:
Preventing DFM issues is preferable to dealing with them later in the circuit design process. Proactively checking for manufacturability is a wise step that addresses problems before they arise.
Staying watchful regarding the design rules and conducting regular checks can prevent the following DFM issues:
Solder Mask Silvers
Slivers, whether copper or solder mask, are small pieces that can cause shorts or interference if redeposited onto other copper areas. If they’re large enough to not float, they can act as antennas, capturing signals due to lack of grounding. To avoid copper slivers, maintain copper features around 0.004 inches, especially the spacing between antipads. While this method isn’t foolproof, it significantly reduces the risk of copper redeposition elsewhere on the layer, depending on the copper weight. Higher copper weights require wider connection areas.
Soldering issues caused by starved thermals
Thermals are small traces surrounding pads that facilitate heat dispersion during soldering and play a crucial role in thermal management. However, voids between the thermal and the plane or the pad can lead to incomplete connections, affecting heat transfer efficiency. Starved thermals result in slower heat transfer during soldering and assembly, leading to soldering issues and prolonged reflow times. Post-manufacturing, boards with starved thermals may experience inadequate heat dissipation, increasing the risk of overheating and damage.
Short Circuit Due to Absence of Clearance Pad
If a pin lacks a clearance pad, it can cause a short circuit. Pins without clearance pads may connect to a plane layer. If there are no clearance pads available from any plane layer for the pin, it will connect to all voltage planes.
Open Circuit Due to Insufficient Annular Ring
When the specified drill size exceeds the annular ring size being drilled, it can lead to an open circuit. This discrepancy may cause the pin to disconnect or result in a short circuit in a voltage plane.
Shorts Caused by Copper Proximity to Board Edge:
Insufficient clearance between copper and the PCB edge can lead to shorts in adjacent layers. When copper is too close to the edge, applying current to the panel between adjacent layers can create shorts. This occurs because of the exposed copper around the perimeter of the board.
PCB Assembly Services with Karkhana.io:
Karkhana.io is your one-stop solution to cater to all your electronic manufacturing requirements. With a network of 500 vetted and certified suppliers nationwide, well-versed in the intricacies of electronics integration and are trusted by top-tier companies, assuring you of optimal results!
Why do we stand out?
- Turnkey and contract manufacturing solutions
- Dedicated assembly lines for high-volume PCB assembly
- Global Sourcing of raw materials
- Integrated Quality Management System
Our flexible manufacturing services enable product efficiency and quality across orders of all sizes from small batches to large volumes, while offering box build solutions along with product localisation capabilities.
If you’re looking for an EMS provider that meets the technical capabilities, contact us today. Let us help you reach the optimal outcome for all your manufacturing requirements. To get started, simply email Pushpalaxmi Vanniyar at pushpalaxmi@karkhana.io with your specifications or fill out the form below.
