Selecting a Suitable Heat Sink

A Heat Sink is a device that enhances heat dissipation by absorbing heat from a hot surface of your electronic device and radiating it to a cooler ambient material (usually air). Proper heat sink selection can solve a lot of thermal problems in your circuit. So how do you select a suitable heat sink for your application?

Before you select a heat sink, go through the following steps

  1. understand whether your application uses Forced Air Flow (air is forcibly moved by a powered device, usually a fan or blower) or Natural Convection (air sits there and does what air does, moving only through natural processes).

  2. calculate the thermal resistance and select the proper parameters from our Heat Sinks parametric filters
    R = (Ts - Ta)/ Pd
    R = Thermal Resistance of the heat sink
    Ts= Temperature of heat sink mounting surface in thermal contact with the device to be cooled (in ºC)
    Ta= Ambient air temperature (in ºC)
    Pd = Power dissipation of the device
    Note: If you can’t find a part with the exact thermal resistance the formula above calls for, it works to choose a heat sink with slightly lower than your calculated thermal resistance. Lower is good, higher is bad.

  3. Select your other requirements for this heat sink - type of package cooled, size, height, shape,attachment method, and anything else your project requires.

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