Our wide range of high-performance heat sink profiles with optimized geometries provide outstanding heat transfer performance. Market leaders in power conversion rely on these profiles for cooling demanding applications like high power semiconductor modules, power converters, renewable energies, traction, energy transmission and large drives.
Find the ideal combination of large surface area, unobstructed heat conduction from heat source to fin surface and low air resistance or pressure drop for your heat dissipation project. Based on our large heatsink profile portfolio, our thermal management experts are pleased to work out a customized heatsink solution that exactly fits your project’s requirements. Get in touch with us now!
A heat sink improves the heat dissipation from an electronic device to the colder environment. This way, the overall thermal resistance of an electronic system can be reduced – and thus the system and component temperature can be lowered. Alternatively, a heat sink allows more power to be dissipated at a specified maximum operating temperature.
Lightness, good thermal conductivity and malleability are the main properties making aluminium the most suitable material for heat dissipation devices. In addition to extruded standard profiles, the product range includes many specialized solutions such as extra wide welded profiles, heat sinks for double-sided mounting as well as brazed and bonded fin heat sinks. Different surface geometries are available to match pressure head and flow rate of fans and blowers.
How to Select a Heat Sink
The performance of a heat sink is defined by its thermal resistance (in K/W) as stated in the supplier's data sheet, which takes into account the heat transfer from the heat sink to the environment by convection and radiation. This thermal resistance depends on several factors: Material (thermal conductivity), shape and size, colour and surface finish (radiation efficiency and contact resistance), installation position (natural or forced convection) and convective power or air flow speed. The lower the thermal resistance, the higher the heat sink performance.
Based on the ambient temperature, the power dissipated by the electronic component, the thermal resistance between its junction and case and the maximum operating temperature, the maximum permissible thermal resistance of the heat sink can be calculated as follows:
Rth = Tj-Ta/Pd - Rth_jc - Rth_ch
where Rth_jc is the thermal resistance between junction and case of the electronic component and Rth_ch is the thermal resistance between case and heat sink, depending on the thermal resistance of the heat-conducting material (usually thermal silicon grease) applied to achieve a contact surface between the housing and the heat sink which is as homogeneous as possible. Based on the resulting value, select a heat sink with a thermal resistance value that is at least equal to or less than the calculated value.
Thermal Resistance Depends on Heat Sink Length
Since thermal resistance decreases with increasing heat sink length according to a nonlinear law, suppliers often give this value for a given profile length, in natural convection and 70 K temperature difference between heat sink and environment at +25 °C ambient temperature. In addition, a value for forced convection with an air flow velocity of 3 m/s and 70 K temperature difference to the environment at +25 °C ambient temperature is often given as well as a diagram to calculate the multiplication factor for the given thermal resistance for different air flow velocities.
This data comes from thermal simulations and tests carried out by suppliers in their laboratories under precisely defined conditions regarding the number, size and placement of the heat sources, the heat conducting material used, the positioning of the temperature sensors, etc. The data is then used to calculate the multiplication factor for the given thermal resistance for different air velocities. Thus, the data can be considered reliable. However, since the working conditions of the heat sinks may differ from those in the laboratory for each custom application, it is recommended to perform thermal tests under application conditions.