TPS736: Thermal Derating

Hi Brian,

I'm unsure which curve diagram you are referring to.  The important consideration here is to not exceed abs max temperature.  The Electrical Characteristics table was generated for temperatures up to +125C, so if you wish to stay within that range then you have +20C rise to work with, otherwise you have +45C rise to stay within the abs max range of +150C. This assumes an ambient temperature of 105C.

Next you need to determine your junction to ambient thermal resistance for your board.  For the 3 values in the datasheet, you have:

DRB: 379mW (20C rise), 852mW (45C rise)
DCQ: 168.5mW (20C rise), 379mW (45C rise)
DBV: 90mW (20C rise), 202.8mW (45C rise)

Now you just need to find the watts dissipated: (Vin - Vout) * Iout = Pdiss

Thanks,

- Stephen

Hi Brian,

Here is the data for Vout = 3.3V.

Thanks,

- Stephen

Here you go:

Thanks,

- Stephen