heat sink for AD815


What is good heat sink for AD815. I burn 6W in my IC. I work in room temp.


  • Hi Navid,

    Thank you for considering ADI parts in your design.

    Could you tell us what your application is? We don't have specific heat sink suggestions. Heat sink selection must be based on the layout of the system, operating environment, size, cost constraints and so on.

    May I ask what your power supplies are you using and so as your input voltages? Also, may I ask why you're 6 Watts? It seems like its too much for the part could handle.



  • Hi Navid,

    Please see the graph below for the plot of the maximum power dissipation of AD815 vs. temperature. As stated in the datasheet, the maximum power that can be safely dissipated by AD815 is limited by the associated rise in junction temperature. The maximum safe junction temperature for the plastic encapsulated parts is determined by the glass transition temperature of the plastic, about 150°C. Exceeding this limit temporarily may cause a shift in parametric performance due to a change in the stresses exerted on the die by the package. Exceeding a junction

    temperature of 175°C for an extended period can result in device failure.

    As you can see, the maximum power dissipation at an ambient temperature of 24 degC is at 2.4 Watts.

    You might also want to consider ADA4870, it is a high speed, high voltage, 1 Amp output drive amplifier that can operate at a wide range of 10V to 40V. The picture below shows the safe operating area curves of output current vs. output stage collector-emitter voltage, under which the amplifier can operate at a safe junction temperature. The area under the curves shows the operational boundaries of ADA4870 for the PCB of the evaluation board that maintains a junction temperature less than or equal to 150 degC. Please refer to the data sheet of this part and go to the heat and thermal management portion on page 20.

    I hope this helps.



  • 0
    •  Analog Employees 
    on Aug 2, 2018 3:16 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin