LM5021: Soldering specification

Hi Jamie,

Reflow profiles are dependent on numerous factors including package type, number of components, board layers, board size, reflow oven accuracy and process and more.

Because of the number of variables it is not possible to provide a single reflow profile that is representative of every board using a specific package type. Typically manufacturing houses have reflow profiles in place and modify them for specific hardware.

For optimal reflow results in achieving consistent solder joint geometries the reflow profile should be developed in cooperation with the solder paste supplier and with the equipment supplier as needed. The solder paste vendor's datasheet includes recommendation for reflow profiles based on alloy melting temperatures and flux activity. These recommendations must be followed to achieve optimal flux activity resulting in wetting of the lead surface. The flux activity in the solder paste plays an important role in facilitating solder wetting resulting in consistent solder joint geometries.

These documents details some of the issues involved here, I believe they will answer most questions:

http://www.ti.com/lit/an/spraby1a/spraby1a.pdf

http://www.ti.com/lit/pdf/SNOA550                Handling & Process Recommendations

http://www.ti.com/lit/pdf/SNOA549                Absolute Maximum Ratings for Soldering 

http://www.ti.com/lit/an/slua271b/slua271b.pdf

http://www.ti.com/lit/an/slta054a/slta054a.pdf                                     

Regards,

Teng