prEN IEC 63378-4:2026

This part of IEC 63378 specifies thermal evaluation board specifications for fine pitch semiconductor packages.
Fine pitch is defined as 0,8 mm or less solder pitch for both BGA and LGA and 0,5 mm or less solder pitch for QFP.
Semiconductor packages are mounted on this thermal evaluation board using solder and then thermal resistance and thermal parameter of the packages are measured.
The obtained thermal resistance and thermal parameter are listed in the datasheets of semiconductor packages.