The DC resistances and leakage inductances were matched to ensure that copper and winding structure were comparable in both parts. The parts were installed in the same board and in the same socket. Thermocouples were embedded in the windings and on the cores to measure temperature rise and determine power loss. Only radiation cooling was allowed. After 30 minutes of operation, the maximum hot spot temperature of the windings and core were measured. These values were averaged to determine power loss using the formula shown here. Test results for the MTPL-2516 were a temperature rise of 55°C versus 82.5°C for the PQ26/20. This equates to a power loss of 2.50 W for the hybrid planar versus 4.78 W for the bobbin wound design, given the surface area for the MTPL was 20.32 cm² versus 23.9 cm² for the PQ26/20. The conclusion was that the MTPL product was 47.6% more efficient with a 23% smaller volume and a 33% lower profile.