Ask the Experts
August 30, 2019
Requirements for Installing Leaded vs. Lead-free Press Fit Connectors
Is there a difference between the requirements to install a leaded press fit connector, and a lead free press fit connector?
Expert Panel Responses
There is no difference. It all depends on connector size and the number of pins. However, there might be a slight difference on the pressure to be applied depending on the PCB surface finish.
Senior Manufacturing Engineer
Edithel is a chemical engineer with 20 year experience in manufacturing & process development for electronic contract manufacturers in US as well as some major OEM's. Involved in SMT, Reflow, Wave and other assembly operations entailing conformal coating and robotics.
There is not difference in mechanical strength, when mounted onto the PCB, most press fit connectors are RoSH compliant, meaning these connectors will be suitable for both, lead and lead free processes. If you are using a lead spec press fit connector, please check the part datasheet, for the following:
Metal used on pins. Reflow maximum temperature.(typically this are 265 degrees celsius, for 5 to 10 seconds.
Process Engineering Manager - Electronics
Altech UEC, South Africa
Currently with Altech UEC and responsible for technology road map in PCBA electronic manufacturing and technical support for PCBA electronic manufacturing for Altech UEC and its JDM's. Over 7 years in SMT, Radial Insertion, Wave solder & Test Applications.
Yes there are different requirements between a leaded press fit connector, and a lead free press fit connector. Check with the manufacturer on the solder-ability of the connector. It might have plating on it that is more suitable for pressing than soldering.
Specifically, you need to know for lead/lead-free soldering incompatibilities with said plating before utilizing. Also, the plastic used might not stand up to either lead/lead free soldering temperatures.
Even if you can solder it, you might want to make "some" of the pins press-fit if only to hold the connector in place while you solder it. If only certain holes are press-fit then flexing and insertion force will be much more manageable.
Note, there is probably information on the manufacturers' web sites that addresses these issues with more detail than I can give you. Check for application notes and white papers. If you are doing volume production then call your mfg. rep or distributor for help.
VP of Advanced Technical Operations
Mark has over 25 years' experience in electronics fabrication, quality and reliability while working for IEC Electronics, GE, Motorola, ORS, etc. He has most recently established IEC Electronics Analysis and Testing Laboratories (IATL), LLC in Albuquerque, NM for electronics and material analysis testing in the military, medical, and industrial industries. His area of expertise includes PCB, PCBA, components, analytical and electrical analysis techniques.