PCB News - "Careful Machine" for PCB Heat Dissipation Layout

"Careful Machine" for PCB Heat Dissipation Layout

The heat dissipation of the PCB circuit board is an indispensable link. If the heat dissipation of the PCB board is not timely, it may cause the components to burn out, the performance consumption is too large and fast, and the life of the PCB board is greatly reduced. Therefore, technicians will consider many factors when making PCB boards, including heat transfer generated by components. After years of discussion and research and development, I finally came to the conclusion: the best way to solve the heat dissipation is to improve the heat dissipation capacity of the PCB itself that is in direct contact with the heating components, and conduct or radiate through the PCB board.

In addition to changing the PCB board, this method is to spend a little thought on the PCB layout. Then we will take a look today. In order to improve the heat dissipation capacity of the PCB board, what should be paid attention to in the PCB layout!

PCB layout

a. Place the heat sensitive device in the cold wind area.

b. Place the temperature detection device in the hottest position.

c. 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 low calorific value or poor heat resistance (such as small signal transistors, small-scale integrated circuits, electrolytic capacitors, etc.) should be placed The uppermost flow of the cooling airflow (at the entrance), and the devices with large heat generation or good heat resistance (such as power transistors, large-scale integrated circuits, etc.) are placed at the lowermost part of the cooling airflow.

d. 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 to the top of the printed board as possible to reduce the temperature of other devices when these devices are working Impact.

e. 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 a 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.

f. The temperature-sensitive device is best placed in the lowest temperature area (such as the bottom of the device). Never place it directly above the heating device. It is best to stagger multiple devices on the horizontal plane.

g. Arrange the devices with the highest power consumption and the highest heat generation near the best position for heat dissipation. Do not place high-heating devices on the corners and peripheral edges of the printed board, unless a heat sink is arranged near it. When designing the power resistor, choose a larger device as much as possible, and make it have enough space for heat dissipation when adjusting the layout of the printed board.