The new technology combination forms a “golden duo,” significantly enhancing power efficiency and reliability.

The new technology combination forms a “golden duo,” significantly enhancing power efficiency and reliability.

In today’s era of rapid technological advancement, the power supply—being the core energy source for all kinds of electronic devices and systems—directly affects device performance, operational stability, and service life through its efficiency and reliability. From everyday consumer devices such as smartphones and laptops to industrial automation equipment and large-scale data centers, and even critical infrastructure like power and telecommunications that underpin national economic development and people’s livelihoods, the efficient and stable operation of power supplies is essential to ensuring the smooth functioning of various sectors. Therefore, continuously exploring and innovating power supply technologies to enhance their efficiency and reliability has always been a relentless pursuit for researchers and engineers.

Recently, a groundbreaking technology combination—integrating a half-bridge resonant LLC topology with CoolMOS switching devices—has emerged as a shining new star in the power supply industry, offering a brand-new solution to enhance power efficiency and reliability. This innovative duo has quickly become the industry’s “golden partnership,” drawing widespread attention. Thanks to its unique operating principle and remarkable advantages, this cutting-edge combination has demonstrated tremendous potential in practical applications and is poised to usher in a whole new stage of development for power supply technology.

The half-bridge resonant LLC topology, as an efficient and high-power-density power supply design, operates like a brilliantly choreographed electrical “dance.” It consists primarily of several key components: two MOSFET switches, a resonant capacitor, a resonant inductor, and a magnetizing inductor. During operation, the two MOSFET switches, under precise control, act like highly trained dancers, alternately turning on and off in a coordinated manner, thereby achieving highly efficient energy conversion and transmission. Among these components, the resonant capacitor and resonant inductor work together to form a resonant circuit. This resonant circuit functions like a magical “energy regulator”—by carefully tuning its resonant parameters, it can skillfully achieve zero-voltage switching (ZVS) during the switching process. It’s as if a layer of “lubricant” has been applied to the switching actions, greatly reducing switching losses and significantly improving system efficiency. Meanwhile, the magnetizing inductor plays a crucial role as a “voltage stabilizer,” precisely adjusting the output voltage according to varying load conditions to ensure that it remains consistently stable, thus providing a steady and reliable power supply for a wide range of devices.

As a leading member of the new-generation power MOSFET family, the CoolMOS switch boasts exceptional performance and has earned widespread acclaim in power supply design. It’s like a “golden key” that unlocks the door to highly efficient power supplies, offering numerous remarkable advantages. First, in terms of two critical metrics for evaluating MOSFET switching performance—Qg (gate charge) and Coss (output capacitance)—CoolMOS excels with remarkably low values for both. This feature significantly reduces energy losses during switching, much like installing an efficient “energy-saving engine” into the power system and strongly driving up overall system efficiency. Second, the fast-recovery body diode integrated within CoolMOS acts like an agile “power guardian,” capable of swiftly completing reverse recovery within an extremely short time frame. This dramatically minimizes energy losses during switching, further enhancing system efficiency. Moreover, CoolMOS features a high breakdown voltage, enabling it to easily meet the demanding requirements of high-voltage applications and providing a solid guarantee of system reliability. In addition, certain CoolMOS models employ a unique Super Junction structure—a design that effectively creates a sophisticated “current highway” inside the switch device. This structure efficiently reduces lateral current flow during switching, lowers the risk of BJT triggering, and significantly improves system stability and reliability.

When the half-bridge resonant LLC topology and CoolMOS switching devices—two technologically powerful forces—join hands, they create a remarkable synergy, much like a perfectly attuned duo that unleashes tremendous power in enhancing power supply efficiency and reliability.

In terms of efficiency enhancement, the combination of these two technologies is nothing short of perfect. The ZVS characteristics of the LLC topology complement CoolMOS’s advantages in low Qg and Coss—much like two highly efficient “energy savers” stacked on top of each other—significantly reducing energy losses during switching transitions. This advantage becomes especially pronounced in high-frequency switching applications, enabling power systems to operate at high speeds while maintaining extremely low energy consumption. By precisely tuning the resonant parameters within the LLC topology—such as the resonant capacitor, resonant inductor, and magnetizing inductance—it’s as if the power system has been meticulously fine-tuned like a high-performance “engine,” further optimizing the system’s operating frequency and switching losses, thereby achieving an even greater overall efficiency boost. In the LLC topology, secondary-side rectification typically employs synchronous rectification technology; and using CoolMOS as the synchronous rectification MOSFET is akin to equipping the rectification stage with an exceptionally efficient “power steward,” which can further reduce voltage stress and losses during rectification, providing yet another powerful boost to system efficiency.

In terms of enhancing reliability, this combination also delivers outstanding performance. Under harsh operating conditions such as power-up, overload, and short circuit, high dv/dt and di/dt levels can trigger the internal BJT in MOSFETs, leading to serious issues like breakdown—much like a power system constantly facing the threat of “power storms.” However, CoolMOS’s fast-recovery body diode and Super Junction structure act as a robust “protective shield,” effectively warding off these “power storms” and preventing the BJT from being triggered, thereby significantly improving system reliability. Thanks to reduced switching losses and rectification losses, the LLC + CoolMOS combination can lower the overall thermal dissipation of the system—akin to installing an efficient “thermal air conditioner” for the power system. This allows the power supply to maintain a lower operating temperature during operation, thus extending its service life. The input-output stability of the LLC topology combined with CoolMOS’s exceptional performance further enhances the system’s resistance to external disturbances—just as if the power system were clad in an “anti-interference armor,” boosting its stability and reliability and ensuring that the power supply can operate steadily even in complex and ever-changing electromagnetic environments.

Currently, the golden duo of half-bridge resonant LLC plus CoolMOS has been widely adopted across multiple fields and has achieved remarkable results. In the server power supply sector, server power supplies employing this combination are like equipping servers with a powerful and stable “heart,” significantly enhancing both efficiency and reliability. Such highly efficient power supplies can reduce server energy consumption, thereby saving data centers substantial operational costs. Thanks to their high power density, these power supplies can be made smaller in size, freeing up valuable space resources in data centers and enabling them to deploy more servers within limited spaces, thus boosting data-processing capabilities. In the field of telecommunications equipment, this combination provides stable and reliable power support, ensuring that communication signals remain unaffected by power fluctuations and guaranteeing uninterrupted communication. Whether it’s at bustling urban telecom base stations or emergency communication devices in remote mountainous regions, you’ll find this technological pairing playing a vital role, safeguarding people’s communication needs. In industrial automation control systems, this golden duo also plays an indispensable role. Industrial production environments are complex and ever-changing, placing extremely high demands on equipment stability and reliability. The combination of half-bridge resonant LLC and CoolMOS delivers stable power to industrial automation equipment, ensuring that devices can operate reliably even under prolonged, high-intensity working conditions, thereby improving production efficiency and reducing losses caused by equipment failures.

Looking ahead, as technology continues to advance and its application fields keep expanding, the golden partnership between the half-bridge resonant LLC converter and CoolMOS switching devices is poised to showcase its unique charm and value in an ever-wider range of applications. Researchers and engineers will continue to delve deeper into the study and optimization of this technological combination, constantly unlocking its full potential and driving power supply technology toward even greater efficiency and reliability. We believe that in the near future, this powerful duo will bring even more remarkable benefits to our daily lives and societal development.