Design and thermal analysis of heat sink for DC/DC power module

Temperature is one of the important factors affecting the reliability of DC/DC power supply circuits. High and low temperatures and their cycling can have severe effects on most electronic components. It will lead to the failure of electronic components, and then cause the failure of the whole power supply. The emergence of multi-chip module (MCM) and high-density three-dimensional assembly technology has made the heat flux density of electronic equipment higher and higher. Scientifically and rationally designing electronic devices to meet their thermal performance requirements is crucial in power module design. The heat pipe has a high-efficiency heat transfer capability, and with reasonable heat dissipation fins, the heat dissipation effect of the radiator will be improved. Based on the numerical heat transfer theory, this paper establishes a set of radiator model of DC/DC power module through the 3D design software Solidworks, and uses the heat flow analysis software EFD.Pro to conduct thermal analysis simulation technology research on the power module.

Introduction

With the miniaturization and miniaturization of electronic components, the high integration of integrated circuits and the development of micro-assembly, the heat flux of components and components continues to increase, and thermal design is also facing severe challenges [1]. The quality of the heat dissipation structure of the power supply directly affects whether the power supply system can work stably for a long time. Based on heat transfer and fluid mechanics, combined with the specific structure of electronic equipment, a reasonable and efficient heat dissipation device is designed, supplemented by advanced thermal analysis software simulation research, to create a good working environment for electronic equipment, to ensure that the heating components and The power system can work stably and reliably under the allowable temperature.

According to the data, in order to ensure the working stability and prolong the service life, the maximum temperature of the chip should not exceed 85°C [2]. For every 10°C increase in the operating temperature of the device, the failure rate doubles [3]. In order to ensure the safety of normal operation of electronic equipment and the reliability of long-term operation, appropriate and reliable methods are used to control the temperature of electronic components so that they do not exceed the maximum temperature required for stable operation under the working environment.

DC/DC power module thermal analysis process

1) Analyze the layout structure of the power supply circuit, and then determine the main heating components.

2) Analyze the thermal circuit corresponding to the power circuit, determine the heat transfer path, and draw an equivalent thermal model.

3) Use Solidworks to build the 3D model of the power radiator, and then use the professional thermal simulation software EFD.Pro to simulate the established model according to the principles of fluid mechanics and numerical heat transfer, combined with the actual thermal boundary conditions.

4) Analyze the simulation results. By simulating the model, analyze whether the simulation results meet the requirements of the normal operation of the power supply.