Best Practices on Footprint Naming Convention (QFN-DFN Version)

  1. Look up your datasheet and open it. Look up the ordering information. Select which part you are going to build and lookup the pin package. In this case, we are going to build the only one in this datasheet which is the MAX19517ETM+ that is a TQFN.
  2. Scroll lower to the package information and lookup the 48 TQFN. For the Footprint Naming Convention, we will use the outline number, the land pattern number and the revisions.
  3. For now, we start with the outline number dash (–) the quantity of revisions dash (-) the revision letter underscore (_) The Land Patter Number dash (–) the quantity of pins with an L for leads.
  4. The final footprint name for this part is 21-0144-4-U_90-0130-44L.
  5. However, there is a special case that may require a longer, more specific footprint name for the QFN-DFN.
  6. Look up your datasheet and open it. Look up the ordering information. Select which part you are going to build and lookup the pin package. In this case, we are going to build the only one in this datasheet which is the MAX1077ETC+T that is a TQFN. 
  7. Scroll lower to the package information and lookup the 12 TQFN. For the Footprint Naming Convention, we will use the outline number, the land pattern number, the revisions and the package type. But why?
  8. For now, we start with the outline number dash (–) the quantity of revisions dash (-) the revision letter underscore (_) The Land Patter Number dash (–) the quantity of pins with an L for leads.
  9. But, considering that there are important dimensions that change corresponding to the package type number, we add it to the footprint name in between the outline number and the land pattern number separated by underscores. Also, if the package number has a + sign, it is exchanged for an underscore (_) in the footprint name since UL does not recognize the + sign in the footprint name.
  10. Taking into consideration all the parameters mentioned above, the final footprint name for the MAX1077ETC+ is 21-0139-5-U_T1244_3_90-0067-12L