January 28, 2014

17

IDTP9167

Advanced Datasheet

Power Dissipation/Thermal Requirements

In addition to layout techniques described in the previous section, placement of the IDTP9167 DPUs with respect to proximity

to other heat generating devices should be considered as well. System dependent considerations such as thermal mounting,

airflow, heat sinking and convection surfaces will affect the final power dissipation limit of the IDTP9167 in application. The

main PCB factors influencing θJA (in the order of decreasing influence) are the number of copper layers, the number of thermal

Vias connecting the device EPAD to the ground plane, and the ground plane thickness.

The maximum power dissipation for a given situation can be calculated from:

������������(������������������)=(������������(������������������)−������������)

������������������

where: PD(MAX)= Maximum Power Dissipation (W)

θJA = Package Thermal Resistance (°C/W)

TJ(MAX) = Maximum Device Junction Temperature (°C)

TA

= Ambient Temperature (°C)

The maximum operating junction temperature (TJ(MAX)) of the IDTP9167 device is 125°C. The thermal resistance of the

DFN-12 package is optimally θJA=36°C/W. Operation is specified for maximum ambient temperature (TA) of 85°C. Therefore,

the maximum power dissipation is:

������������(������������������)=(������������������°������−������������°������)

������������°������/������ =������.������������