I am designing a heat spreading for EPC2152. I want to only use a heat sink solution without airflow cooling. I have calculated my expected total losses for EPC2152 to be 3W maximum. I was wondering what is the best and easiest solution for me. Can I use only the heatsink without a fan?
According to the 3W losses you calculated, it depends on the heatsink you will use. It is likely likely that you will not need any fan. The EPC90120 is a development board for the EPC2152. Without heatsink, the EPC90120 is expected to have about 100C temperature rise. If you add some top cooling and even a minimal heatsink, the temperature rise will be more manageable. For a more precise evaluation you can refer to our online tool: https://epc-co.com/epc/design-support/gan-power-bench/gan-fet-thermal-calculator. If you use 100LFM as airflow, then you can consider about twice the thermal resistance with natural convection.