TPA3255: TPA3255 thermal pad usage ..

Hi Emil,

Thermal considerations have a number of factors that will contribute to performance that are hard to generalize. This could be starting ambient, air flow, heatsink material, etc. so I wont be able to give you a precise thermal conductivity that will work for your system. Next would be how you define your 2x150W rating, is this peak, continuous (>1min) or actual continuous (indefinite)? Is the test done with a 1k sine wave to create the 150W?

However, we have done some thermal pad testing with the EVM in open air and found that if you want 2x150W into 4R continuous (>1min) sine wave with the heatsink on the EVM, then the thermal coefficient we found should be around 4.5 W/mK.

Of course this is all just a suggestion and will need to be tested in your final system.

Justin

Hi Justin,

Thank you for your answer.

It is home based system ... it will be used at low levels .... maybe no more than 2 x 10 ... 2 x 20 W ..

So I will try with  6 W/mK thermal pad ...

Best regards,

Emil