SNVSCN6 December 2023 TLVM365R1 , TLVM365R15
PRODUCTION DATA
As with any power conversion device, the TLVM365R15 dissipates internal power while operating. The effect of this power dissipation is to raise the internal temperature of the power module above ambient. The internal die and inductor temperature (TJ) is a function of the ambient temperature, the power loss, and the effective thermal resistance, RθJA, of the module and PCB combination. The maximum junction temperature for the TLVM365R15 must be limited to 125°C. This limit establishes a limit on the maximum module power dissipation and, therefore, the load current. Equation 9 shows the relationships between the important parameters. Seeing that larger ambient temperatures (TA) and larger values of RθJA reduce the maximum available output current is easy. Being that the power dissipation is relatively low in this module, this device must be capable of supporting the maximum ambient temperature rating, across the majority of power conditions with a modest size 2 layer or 4 layer PCB. Further thermal analysis can be done by measuring the top case temperature on the EVM which is nearly equivalent to the junction due to the thin case.
As stated in the Semiconductor and IC Package Thermal Metrics application report, the values given in Section 6.4 section are not valid for design purposes and must not be used to estimate the thermal performance of the application. The values reported in that table were measured under a specific set of conditions that are rarely obtained in an actual application.
where
The effective RθJA is a critical parameter and depends on many factors such as the following:
The IC Power loss mentioned above is the overall power loss minus the loss that comes from the inductor DC resistance. The overall power loss can be approximated by using WEBENCH for a specific operating condition and temperature.
Use the following resources as guides to optimal thermal PCB design and estimating RθJA for a given application environment: