The horn-shaped fin design can improve the heat dissipation efficiency of the pin fin heat sink
The horn-shaped fin design can improve the heat dissipation efficiency of the pin fin heat sink.
In recent years, the functions of cutting-edge FPGAs have rapidly developed to unprecedented heights. Unfortunately, the rapid development of functions has also increased the demand for heat dissipation. Therefore, designers need more efficient heat sinks to provide sufficient cooling requirements for integrated circuits.
In order to meet the above needs, thermal management suppliers have introduced a variety of high-performance heat sink design solutions that can provide a stronger cooling effect under a given capacity. The horn-shaped pin fin radiator is one of the more important technologies introduced in recent years. This kind of heat sink was originally designed for FPGA cooling, and some of its characteristics make it particularly suitable for ordinary FPGA environments.
Better cooling and airflow management.
flared pin fin heat sink is equipped with a series of cylindrical pins. As shown in Figure 1, these pins serve as fins for the heat sink and are arranged in an outwardly inclined shape. Due to its unique physical structure, the horn-shaped pin fin heat sink is optimized for low- and medium-speed airflow environments, and it can achieve an unprecedented cooling effect in this environment. The material of this type of heat sink can be copper or aluminum, and the footprint ranges from 0.54×0.54 inches to 2.05×2.05 inches, and the height ranges from less than half an inch to just over one inch. This size can meet the requirements of various sizes of FPGAs.
The horn-shaped pin fin heat sink is a derivative development of the traditional heat sink, and the traditional fins are arranged vertically (see Figure 2). In order to understand the cooling characteristics of the horn-shaped pin fin heat sink, we should first understand the cooling properties of the traditional radiator. The cooling performance of the traditional heat sink is also very good, mainly reflected in the low thermal resistance. The unit of thermal resistance is °C/W, which is used to measure the number of degrees Celsius (higher than the ambient temperature) that the device consumes per watt of power to cause the temperature to rise.
The low thermal resistance of traditional pin-fin heat sinks is mainly due to the following characteristics: cylindrical pins, the omnidirectional structure of the pin array and its large surface area, and the high thermal conductivity of the base and pins, etc. Helps improve the performance of the heat sink. Compared with square or rectangular fins, cylindrical pins have lower resistance to airflow. Coupled with the omnidirectional structure of the pin array, it helps the surrounding airflow to enter and exit the pin array easily.
To achieve a significant cooling effect, the heat sink must have sufficient surface area, otherwise, if the surface area is too small, the heat sink cannot dissipate enough heat. At the same time, if the surface area of the heat sink is larger (the more pins it contains), the more difficult it is for the surrounding airflow to enter the pin array. Unfortunately, if the heat sink is not fully exposed to the surrounding airflow, no matter how large its surface area, it will not be able to effectively dissipate heat.
Enlarge the pin spacing to allow air to circulate more easily. The speed at which the air passes through the heat sink should be close to the speed at which the air enters the heat sink.
By making the pin arrangement more compact to increase the surface area, the cooling performance of the heat sink can be improved. However, doing so will hinder the airflow, thereby reducing the heat dissipation performance. This is an inherent contradiction that suppliers must face when designing vertical pin heat sinks.
However, by bending the pins outward, the horn-shaped pins effectively overcome the contradiction between surface area and pin density. This method greatly increases the spacing between the pins in a given area. Therefore, the surrounding airflow can enter and exit the pin array more conveniently. The surface of the heat sink is exposed to the air with a faster flow rate, and the heat dissipation capacity is also greatly increased as a result. This improvement is especially noticeable when the airflow velocity is low, because the slower the airflow velocity, the more difficult it is for the surrounding air to enter the heat sink pin array. Therefore, the horn-shaped pin heat sink is most suitable for environments with low air velocity.
