Causes of high temperature failure of dcdc power supply modules

dcdc power moduleIt is a switching power supply that uses power semiconductor switching devices to achieve dcdc power conversion. It is widely used in long-distance and data communications, computers, office automation equipment, industrial instrumentation, military, aerospace and other fields, involving various industries in the national economy, and has broad application prospects in the field of long-distance and digital communications. With the rapid development of electronic technology and the wider application field of switching power supply, the working environment is getting worse and worse. Statistics show that every time the temperature of electronic components increases by 2℃, the reliability decreases by 10%, and the temperature rises. The lifetime at 50°C is only 1/6 of the temperature rise at 25°C.

In order to ensure the stability of the DCDC power module and prolong the service life, the high temperature of the chip must not exceed 85°C. Each time the operating temperature of the device increases by 10°C, its failure rate doubles. In order to ensure the safety of normal operation of electronic equipment and the reliability of long-term operation, appropriate and reliable methods are adopted to control the temperature of electronic components so that they do not exceed the high temperature required for stable operation under the working environment conditions.

The temperature characteristics of the module are as follows: when the temperature is less than 150, the output voltage of the module decreases slowly, which is caused by the decrease of the optocoupler current transmission ratio; when the temperature is greater than 150, the output voltage of the power module drops rapidly, even the output voltage is almost equal to Zero, the reason is that the core temperature of the transformer in the module is close to the Curie point temperature (220). Caused by failure of the transformer. In this case, if there is no other damage inside the module, when the heating is stopped, the temperature of the module returns to room temperature, and the module is re-powered, the output voltage of the module can still return to the normal value.

With the development of miniaturization and micro-miniaturization of electronic components, high integration of integrated circuits and micro-assembly, the heat flux density of components and components has improved from time to time, and thermal design is also facing severe challenges. 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, the detailed structure of electronic equipment is separated, reasonable and efficient heat dissipation installation is designed, supplemented by advanced thermal analysis software simulation research, to invent a good working environment for electronic equipment and ensure heating components And the power system can work stably and reliably under the allowable temperature.