This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPS82085: Junction-to-Case and Junction-to-Board Thermal Resistance

Part Number: TPS82085
Other Parts Discussed in Thread: TPS62088, TPS8268180

Hi all, it is nice to find you here. I have some questions about how to use TPS82085,

  • How to calculate the case temperature and junction temperature? Please provide some specific formula.
  • If this device works at Io=3A, Vin=5V, Vo=3.3V at long time, will it have some risk if it always works at max load?
  • If I want to choose a much smaller DCDC module to meet above requirements. Do you have some other solution to recommend?

Thank you very much!

  • Hi Charles,

    This app note discusses this topic is great detail: www.ti.com/.../slva658.pdf And this app note explains the thermal terms: www.ti.com/.../spra953c.pdf Case temperature is usually measured. For this device (and most devices), the case temperature is very close to the junction temperature due to the low Psi JT value.

    Figure 10 provides derating information for very similar conditions. I don't see an issue for board temperatures less than 85 C.

    This is already incredibly small for a 3A module. But we have TPS62088 (3A non-module) and TPS8268180 (1.6A module) which are smaller.