Solder Limits: Updating UL Recognized PCBs for the Age of Surface Mount

The presentation will primarily focus on PCBs that have UL Recognition but will also touch on the Recognized materials used to manufacture them (laminates and solder resists).

We will start by looking at what UL PCB Recognition is designed to achieve. From here we will then move to Solder Limits and what this parameter represents and why it is such an important element in the UL Recognition process for the Printed Circuit Board.

The vast majority of PCBs are currently Recognized with Solder Limits based on a traditional solder fl oat test and we will look at what is required to update these to refl ect the soldering the PCB is exposed to during today’s assembly processes, which is typically multiple cycles of SMT refl ow soldering plus wave / selective soldering operations.

We will then look at how this will be implemented in the industry. At the time of writing this, UL are listening to the concerns of the industry and actively working with groups such as the FED to fi nd a solution that gets us to the appropriate Solder Limits for the reality of today’s soldering processes but with the minimum impact to the PCB industry and its material suppliers. At the conference I will provide the most up-to-date situation and what the next steps will be. We also welcome input prior to this event, as the only way to resolve this is by working together.

Emma Hudson

PCB Industry Leader – Europe, Middle East, Africa and Latin

Emma graduated from Coventry University with a Bachelor of Engineering in Materials Technology. She spent the following six years working in automotive electronics assembly (at TRW), running the Process and Materials Laboratory for three sites manufacturing safety critical ECUs. In 2006 Emma joined UL and focused her previous electronics experience on helping the PCB industry through the safety certifi cation process. Emma is also the Vice President and Treasurer of the European Institute for the PCB Community (EIPC) and Chair of the British committee for Electronics Assembly Technology.