Basic principles of power module custom thermal design

Simplified heat dissipationModule power customizationOne of the important characteristics of time. Although there are many reasons for the failure of electronic equipment, high temperature is an important factor among them, and the influence of temperature on electronic equipment is as high as 60%. Due to the high efficiency of the converter, the heat generated is very small, and the ultra-thin package is used to provide a heat dissipation interface that is convenient for installation and electrical isolation. Taking proper heat dissipation measures can improve the working conditions of the converter, increase the mean time between failures of the system, reduce the volume of the converter module, and also reduce costs and extend the service life.

1. From the perspective of conducive to heat dissipation, if the printed plate is installed upright, the distance between the board and the board should generally not be less than 20mm;

2. In the horizontal direction, high-power devices are placed as close to the edge of the printed board as possible to shorten the heat transfer path; in the vertical direction, high-power devices are placed as close as possible to the top of the printed board to reduce the temperature of other devices when these devices are working. Impact.

3. The devices on the same printed board should be arranged as far as possible according to their calorific value and degree of heat dissipation. Devices with small calorific value or poor heat resistance (such as small signal transistors, small-scale integrated circuits, electrolytic capacitors, etc.) should be placed On the upstream of the cooling airflow (at the entrance), devices with large heat or heat resistance (such as power transistors, large-scale integrated circuits, etc.) are placed downstream of the cooling airflow.

4. Devices that are sensitive to temperature should be placed in low temperature areas (such as the bottom of the device). Never place them directly above the heating device. If multiple devices are arranged in a staggered horizontal plane.

5. The heat dissipation of the printed board in the equipment mainly relies on air flow, so the air flow path should be studied during the design, and the device or printed circuit board should be reasonably configured. When air flows, it always tends to flow in places with low resistance, so when configuring devices on the printed circuit board, avoid leaving a large airspace in a certain area. The configuration of multiple printed circuit boards in the whole machine should also pay attention to the same problem.