Note 8: Junction to ambient thermal resistance (

standard JESD51-17. The test board is a 4 layer FR-4 board measuring 102mm x 76mm x 1.6mm witha3x2 array of thermal vias. The ground plane on the board

is 50mm x 50 mm. Thickness of copper layers are 36mm/18mm/18mm/36mm (1.5oz/10z/1oz/1.5ox). Ambient temperature in simulation is 22˚C, still air. Power

dissipation is 1W. (The DAP is soldered.) Fore more information on LLP thermal topics, as well as LLP mounting and soldering specifications please refer to

Application Note 1187: Leadless Leadframe Package (LLP).

Note 9: Exposed DAP soldered to an exposed 1sq. inch area of 1 oz. copper. Thermal resistance can be decreased by using more copper are to dissipate heat.

www.national.com

5