Do I have to use heatsink?
ADV7185 consumes a lot of power. Please see attachment for details. This gives
the JUNCTION temperature for different operating conditions. This is the
important parameter as far as the operation of the circuit is concerned. If
>150degC the part will operate unreliably. Unless it is a very special
application, you don't really care what the surface tempreature of the package
is. The purpose of using a heat sink is to reduce the junction temperature.
Whether you need a heatsink depends on the following factors
- The temperature rise above ambient temperature (calculated using the package
thermal impedance and the power dissipation)
- The worst case ambient tempreature of the air around the package
- Whether there is forced air cooling i.e. a fan.
- Whether the part is on a 2 4 or 6 layer board