Roland, do you mean the thermal resistance of the complete package? The anodized heat sink is in contact with the PCB, I presume. What kind of thermal interface material is between the heat sink and the PCB? The heat sink is adjacent to the ENIG- 30-micron Cu? Sometimes Technetters post or improvise pictures of the layup. At best, your question is a challenging one. Bonne chance....Louis Hart -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Roland Jaquet Sent: Tuesday, April 22, 2014 4:06 AM To: [log in to unmask] Subject: [TN] Seeking : Thermal Resistance onto PCB surface Dear Technetters, I am confronted to an unusual challenge I am not able to solve. Can someone help, if you please We are seeking : Thermal Resistance onto PCB surface (14 layers) standard approx.. 1.8 mm thick Between External Cu of approximately 30 to 35 metric microns covered with ENIG And Aluminum "Alodinized" 1200 or Anodized in black Thank you for your help Meilleures salutations Best Regards Roland ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________