Measure applied pressure using a calibrated pressure sensor on multiple locations between the device and the heat sink assembly as shown in This Figure .
RECOMMENDED: AMD recommends that the applied pressure on the package be in the range of 20 to 50 psi for optimum performance of the thermal interface material (TIM) between the package and the heat sink. Thermocouples should not be present between the package and the heat sink, as their presence will degrade the thermal contact and result in incorrect thermal measurements. The best practice is to select the appropriate pressure (in the 20 to 50 psi range) for the optimum thermal contact performance between the package and the thermal system solution, and the mechanical integrity of the package (with the thermal solution to pass all mechanical stress and vibration qualification tests).
TIP:
These recommendations and specifications are the same for both lidded and lidless devices.
RECOMMENDED: AMD recommends using dynamic mounting around the four corners of the device package. On the PCB, use a bracket clip as part of the heat sink attachment to provide mechanical package support. See This Figure .
