In the current trend of fast charging, continuous miniaturization and high power of power modules, MOS transistors, as core power devices, often need to withstand high currents, high temperatures, and frequent working impacts. The heating problem of MOS transistors directly affects the efficiency and reliability of the entire charging module. If the heat dissipation is not timely, there may be a risk of excessive temperature rise, device performance degradation, or even failure.
Therefore, how to achieve efficient heat dissipation at the bottom of MOS transistors while balancing adhesion and reliability has become a focus of attention for major power supply manufacturers.
Background and Challenges
In practical applications, there are several common solutions for heat dissipation at the bottom of MOS tubes in charging modules, including:
Thermal pad: requires manual cutting and screw fixation, making assembly complex;
Gap Filler: Similar to a soft cushion after curing, it has thermal conductivity but no adhesive force;
RTV thermal conductive silicone: has adhesive properties, but has a long curing time at room temperature, which is not conducive to mass production;
Thermal conductive silicone grease: It has good thermal conductivity in the initial stage, but it is prone to drying out after high temperature and long-term aging, resulting in a significant decrease in thermal conductivity.
These traditional methods either have complex processes or lack long-term reliability, and cannot simultaneously meet the needs of “bonding+thermal conductivity+reliability”.
Solution: SIPA 1921 high thermal conductivity silicone
To solve this problem, a customer introduced Elaplus SIPA 1921 single component high thermal conductivity silicone gel in the bottom heat dissipation bonding process of MOS tubes.
This material adopts a thermosetting and molded silicone system, and achieves a balance between high thermal conductivity and high strength adhesive force through a special liquid powder two-phase combination process.
Bottom heat dissipation adhesive of MOS tube in charging module
120 ℃ can cure in 30 minutes, greatly improving production efficiency;
After curing, a high thermal conductivity elastic buffer layer is formed, which has both heat dissipation and shock absorption functions;
Single component, semi thixotropic design, easy to apply glue without flowing;
Good adhesion to common substrates such as metal, glass, ceramics, etc., without the need for a primer;
ROHS/REACH certification and compliance with UL 94 V-0 flame retardant standard;
Maintain elasticity and stability within a wide temperature range of -50 ℃ to+280 ℃.
View SIPA 1921 details
Customer usage effect
In the project application, the customer applied SIPA 1921 dots between the bottom of the MOS transistor and the heat dissipation substrate:
Alternative thermal pad: eliminates cutting and screw fixing processes, increases assembly efficiency by more than 30%;
Replacing silicone grease: avoids the problem of migration or drying at high temperatures, ensuring long-term stability and reliability;
Improving heat dissipation efficiency: The measured average operating temperature of MOS transistors has decreased by about 10-15 ℃, effectively ensuring the lifespan of the devices;
Strengthening adhesion protection: After curing, it has flexibility, balancing adhesion and shock absorption, avoiding weld cracking caused by thermal expansion stress.
Customer feedback: “SIPA 1921 not only solves the heat dissipation problem, but also simplifies the assembly process, allowing us to benefit from both cost and reliability. ”
In the application scenario of heat dissipation bonding at the bottom of MOS tubes in charging modules, Elaplus SIPA 1921 high thermal conductivity silicone has perfectly replaced traditional thermal pads, silicone grease, and RTV silicone with its high thermal conductivity, strong adhesion, fast curing, and long-term reliability, becoming a better choice.
If you are looking for a solution that balances heat dissipation, adhesion, and long-term stability, SIPA 1921 would be a high-performance material worth trying.
Tags: MOS tube bottom bonding · SIPA 1921 · Charger heat dissipation solution · Charging module heat dissipation adhesive · Single component silicone gel · Thermal conductive silicone gel
