What thermal insulating material is used for MOSFET heat dissipation? what’s the effect?

With the rapid development of the modern electronics industry, the integration of power devices of electronic products is getting higher and higher, and the problem of heat generation is becoming more and more serious, and it has seriously affected the service life and reliability of products.

When the MOSFET heat sink is working, the heat generation is very large. If the MOSFET heat dissipation effect is not good, the temperature may be too high, which may cause the MOSFET to be burned, which may lead to the damage of the entire circuit board. The traditional high-power inverter MOSFET is arranged on the circuit board, and the radiator is also arranged on the circuit board. The MOSFET is in contact with the radiator. When the circuit is working, the heat dissipated by the MOSFET is quickly dissipated by the radiator.

If the circuit power is high, the number of MOSFET will be relatively large. According to the current MOSFET heat dissipation structure, the length of the radiator and the circuit board can only be increased to provide heat dissipation for all MOSFET, which will increase the volume of the chassis. The heat dissipation structure has poor heat dissipation effect. Some high-power inverter MOSFET will install ventilation paper to dissipate heat, but it is very troublesome to install ventilation paper. Therefore, MOSFETs have high requirements for heat dissipation, and the heat dissipation conditions are divided into the lowest and the highest, that is, the upper and lower floating range of the heat dissipation during operation. Generally, the worst heat dissipation conditions are used as the standard when purchasing, so that the maximum safety margin can be left during use, and the normal operation of the system can be ensured even in high temperatures.

At present, screws are used to fasten the MOSFET and the heat sink. The MOSFET is a device that generates a relatively large amount of heat, so it is generally equipped with a heat sink when it is used, usually a small aluminum heat sink. In order to improve the heat dissipation performance, the heat of the MOSFET must be introduced into the radiator as much as possible, and the thermal resistance between the MOSFET and the radiator needs to be reduced, so what thermal insulation material is better to choose?

I have also seen the use of soft thermal pads when disassembling some electronic products. CoolThermo feels that the soft thermal pad is still not very safe, because the strength is not enough, it is easy to damage the adhesive layer when the screw is installed, and the breakdown occurs. Therefore, thermally conductive insulating sheets are generally used. The strength of the thermal insulation sheet should also be considered, and it must withstand a certain amount of tightening force without being damaged.

It is worth mentioning that MOSFET usually adopts the design of heat sink and thermal conductive silicone to directly contact heat dissipation. If the MOSFET shell cannot be grounded, it can be isolated by insulating gasket and then used thermal conductive silicone grease to dissipate heat. Silicone sheets can also be used to cover the MOSFET, which can prevent static electricity damage in addition to heat dissipation.

Installing thermally conductive insulating material between the MOSFET and the heat sink can greatly reduce the interface thermal resistance, increase the heat dissipation efficiency, ensure that the MOSFET operating temperature is maintained within a reasonable range, and enable the system to operate stably and reliably.

Which thermal interface materials can be back glued? What does it do?

Thermal interface material adhesive generally refers to a layer of double-sided tape on the surface of the original material, one side is attached to the thermally conductive material, and the other side is leaking out. During use, tearing off a layer of protective film on the surface can play a fixed role. . Of course, there are also double-sided adhesive, the method is the same as single-sided. Some thermally conductive materials have some stickiness themselves, so they can be used without adhesive. This adhesive is made according to customer needs.

The thermally conductive interface materials that can be backed include: thermally conductive silicone sheet, thermally conductive silicone cloth, etc.

Thermal silicone pad

The thermally conductive silicone sheet is specially produced for the design scheme of using the gap to transfer heat. It can fill the gap and complete the heat transfer between the heat-generating part and the heat-dissipating part. Thinning design requirements, with manufacturability and applicability, and a wide range of thicknesses, a good thermal conductive filling material.

The thermally conductive silicone sheet has natural viscosity, and the purpose of the adhesive is for better viscosity. At the same time, the thermally conductive silicone sheet with adhesive backing will increase the thermal resistance and reduce its thermal conductivity. Therefore, when you buy thermally conductive silicone sheets, you should decide whether to back glue according to your own needs.

Thermal insulation sheet

Thermal insulation sheet is a silicone polymer elastomer reinforced with glass fiber as a base material, also known as thermally conductive silicone cloth, tear-resistant silicone cloth, this silicone cloth can effectively reduce the gap between electronic components and radiators. High thermal resistance and electrical insulation, high dielectric strength, good thermal conductivity, high chemical resistance, can withstand high voltage and short circuit caused by metal puncture, is a substitute for traditional mica and silicone grease An excellent thermal insulation material.

The thermal conductive silicone cloth itself has no adhesive backing, that is, it is not sticky. The advantages of the thermal conductive silicone cloth are strong breakdown resistance, wear resistance, tear resistance, puncture resistance, good high-voltage insulation performance, and thin thickness. It can also be glued back.

The above two thermal interface materials are produced in large quantities by Nuofeng NFION Thermal Materials Factory, which are also hot-selling products, and are widely used. They can be customized according to customer needs with adhesive, die-cutting and different specifications.

What material is the thermal insulation sheet made of? What are the characteristics? In which fields is it applied?

With the continuous development of society, new things are constantly emerging. Artificial intelligence and automation have changed people’s way of life and work. Large-scale machinery and equipment are flooding people’s side, bringing indelible contributions to social development. At the same time, its security risks also attract people’s attention all the time.

At present, most of the machinery and equipment used in society are driven by electrical energy, and when the current passes through the resistance, heat will be generated. The greater the power consumption of the machinery and equipment, the higher the heat generated. If the heat is not dissipated in time, the machine may crash due to the high internal temperature, or even cause the internal parts to burn, causing a safety hazard.

There is a gap between the heat source and the radiator. Even if there are two smooth and flat planes, there are still some large and small holes on the surface. Therefore, the air between the two contact gaps hinders the efficiency of heat conduction, so that heat is transferred from heat to heat dissipation. efficiency slows down. Thermal conductive material is a thermal conductive medium material that can effectively solve the serious heat generation. It mainly acts between the heat source and the radiator, and plays its role as a heat conduction medium.

When the voltage on both sides of the insulator continues to increase, the electric field force on the charge in the insulator material will be greater, which will easily lead to ionization collision, resulting in the breakdown of the insulator. This phenomenon is called insulation breakdown, and this phenomenon exists widely. It is used in machinery and equipment with high power consumption, and it brings security risks. Therefore, a material that can withstand high breakdown voltage and conduct heat at the same time is required. Therefore, thermally conductive silicone cloth was born for this reason.

Thermally conductive silicone cloth is a silicone polymer elastomer reinforced with glass fiber as a base material, also known as thermally conductive silicone cloth, tear-resistant silicone cloth, this silicone cloth can effectively reduce the gap between electronic components and radiators. High thermal resistance, and electrical insulation, high dielectric strength, good thermal conductivity, high chemical resistance, can withstand high voltage and metal parts puncture caused by circuit short circuit, and thermal conductive silicone cloth has strong temperature resistance, It can avoid aging and deterioration due to long-term overheating. It is an excellent thermal insulation material to replace traditional mica and silicone grease.

The thermal conductive silicone cloth is characterized by ultra-thin and high insulation. Its thickness is in the range of 0.2-0.5mm. It can be used in some small but charged environments, filling gaps, reducing breakdown thermal resistance, and improving thermal conductivity. Ordinary thermal pads cannot To achieve high insulation, it is easy to be broken down by high voltage, so the thermal conductive silicone cloth can ensure the safe and reliable operation of machinery and equipment for a long time.

In the electronics industry, thermally conductive insulating silicone cloth is mainly used for the transfer interface between electronic equipment and heat sinks or product shells. , No additional surface amount adhesive, meet the environmental requirements of the public and UL, so it is widely used in switching power supplies, communication equipment, computers, flat-panel TVs, mobile equipment, video equipment, network products, household appliances and other fields.

The above is what material the thermally conductive silicone cloth is made of? What are the characteristics? In which fields is it applied? For related introduction, if you are interested in thermal conductive silicone cloth material, you can consult the online customer service of the thermal conductive silicone cloth manufacturer and look forward to your arrival.

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