Design for Manufacturing (DFM) Checks

We know that getting high quality boards, on time, matters. Designing your boards in such a way to avoid manufacturing pitfalls is essential to achieving this goal. To help, we check for the following DFM issues before and during production.

If our boards violate IPC standards due to any of the following DFM issues, we will make them again for free.

 

Fabrication Issues

Trace layers:

  1. Incomplete Files
  2. Minimum Trace & Space Violations
  3. Netlist shorts and/or broken circuits
  4. Non-plated through holes to copper
  5. Minimum distance from copper feature to route
  6. Distance from cut-out and mill to copper
  7. Landless pads, which are pads that are not connected to any traces
  8. Pads outside the route path
  9. Empty layers due to bad conversion
  10. Disconnected traces
  11. Via in SMT pads
  12. Controlled impedance requirements not met

Positive/negative plane:

  1. Minimum distance from drill to copper
  2. Non-plated through holes to copper distance
  3. Copper slivers
  4. Acid traps, copper features at an acute angle that may cause chemical entrapment
  5. Proper copper balancing
  6. Unintended copper connections and misconnected traces Netlist shorts and/or broken circuits

Solder Mask Layer:

  1. Solder Mask pad clearance
  2. Solder Mask minimum web
  3. Solder Mask missing pad clearance
  4. Solder Mask bridging clearance
  5. Extra Solder Mask clearance in unintended regions
  6. Missing Solder Mask clearance for Planted or non-plated through holes
  7. Missing Solder Mask clearance for test points
  8. Solder Mask covering plated edges
  9. Solder Mask clearance exposing traces
  10. Solder Mask slivers

Silkscreen Layer:

  1. Silkscreen overlapping solder mask free regions (such as pads)
  2. Minimum Silkscreen feature width manufacturable
  3. Silkscreen unreadable

Assembly Issues:

  1. Via-In-Pad
  2. Component to pad mismatch (SMT & PTH)
  3. Via to pad or shared pads with no solder dams
  4. Missing solder dams
  5. Gang masking fine pitch or leadless components
  6. Side mounted parts (straddling edge of PCB)
  7. Silkscreen over pad errors
  8. Component clearance to PCB edge
  9. Component clearance to adjacent components
  10. RoHS/Leaded component conflict with process (e.g. lead balled BGA for RoHS process)
  11. Moisture sensitive components
  12. Temperature sensitive components
  13. Insufficient or poor support for flex circuits
  14. Insufficient thermal relief for SMT & PTH pads
  15. Component pin 1 or clear polarity identification (diodes, electrolytic/tantalum capacitors, etc.)
  16. Missing solder mask relief from pads (typical 3 mil)