With the prevalence of hundred-watt chargers and portable power banks, high-power devices have also started to use USB Type-C interfaces for power supply, forming a complete ecosystem and accelerating the adoption of USB Power Delivery (PD). However, for high-performance computing devices, the 100W power provided by the USB PD3.0 protocol is not sufficient. The newly launched USB PD3.1 protocol extends the output range of USB PD3.0, supporting 28V, 36V, and 48V outputs with a maximum power of 240W, meeting the power supply requirements of high-power devices.
In the design of PD 3.1 high-power power supplies, the application of half-bridge topology is becoming increasingly common. The use of discrete gallium nitride (GaN) devices in half-bridge topologies not only occupies a large board area but is also susceptible to interference from parasitic inductances, affecting the efficiency of the power supply system. Consequently, more and more manufacturers are introducing half-bridge GaN integrated power modules (IPMs), which encapsulate two half-bridge GaN devices and drivers within a single chip, simplifying the design of half-bridge topology power supplies.
Full-Wave Phase Current Half-Bridge GaN IPM by Liangxin Micro
Liangxin Micro is preparing to launch a half-bridge GaN IPM featuring 0.1% accuracy, thermal-free, positive and negative current detection, and a voltage rating of 1200V. This half-bridge GaN IPM integrates a 60V~1200V half-bridge GaN, with built-in 0.1% accuracy, 50ns response time, and thermal-free current sampling. Its heat generation is only one-ten-thousandth of that of manganin, and its intelligent overcurrent protection ensures the safety and reliability of the power supply. Additionally, it integrates an isolated half-bridge driver, bootstrap circuit, isolated ADC, and NTC.
Infineon IGI60F1414A1L
Infineon's half-bridge GaN integrated power stage chip, IGI60F1414A1L, is suitable for low to medium power range applications requiring small and lightweight designs. With an 8x8 QFN-28 package, it is optimized for thermal performance, providing high power density for the system. The chip comprises two 140 mΩ / 600 V CoolGaN enhanced (e-mode) HEMT switches and an electrical isolation-dedicated high-side and low-side gate driver from Infineon's EiceDRIVER series. The isolated gate driver features two digital PWM inputs, simplifying control of the IGI60F1414A1L. To shorten development time, reduce system bill of materials (BOM), and lower overall costs, the chip leverages integrated isolation capabilities, clear separation of digital and power grounds, and simplified PCB configurations. The gate driver employs Infineon's single-chip coreless transformer (CT) technology for effective input-output isolation, ensuring high-speed performance and outstanding stability even during ultra-fast switching transients with voltage slew rates exceeding 150 V/ns.
Innoscience ISG3201
Innoscience's ISG3201 is a 100V rated half-bridge GaN power chip that encapsulates two 100V, 3.2mΩ enhanced-mode GaN switches and a 100V half-bridge driver within. The integrated driver eliminates the need for external clamping circuits, significantly reducing associated parasitic parameters. The half-bridge GaN devices offer a continuous current capability of 60A, zero reverse recovery charge, and extremely low on-resistance. ISG3201's minimal external components include integrated drive resistors, bootstrap capacitors, and supply filter capacitors. Innoscience adopts a solidified drive form for this chip, reducing parasitic inductances in the gate and power loops and simplifying power path design. The chip features independent high-side and low-side PWM signal inputs, supports TTL-level driving, and can be driven by dedicated controllers or general-purpose MCUs. In terms of applications, the ISG3201 half-bridge GaN power chip is suitable for high-frequency, high-power-density buck converters, half-bridge and full-bridge converters, class-D audio amplifiers, LLC converters, and power modules, making it ideal for AI, servers, communications, data centers, and other scenarios. Its 48V operating voltage also meets the requirements of USB PD 3.1 fast charging and outdoor power supply applications, simplifying the development and design of power components through integrated half-bridge devices.
Texas Instruments LMG5200
The LMG5200 integrates an 80V, 10A driver and a GaN half-bridge power stage, offering a comprehensive integrated power stage solution with enhanced-mode gallium nitride (GaN) FETs. This device comprises two 80V GaN FETs, which are driven by a common high-frequency GaN FET driver configured in a half-bridge arrangement. GaN FETs exhibit remarkable advantages in power conversion due to their nearly zero reverse recovery charge and exceptionally low input capacitance (CISS). All components are mounted on a fully bond-wire-free packaging platform, minimizing the number of parasitic elements within the package. The LMG5200 is packaged in a 6mm×8mm×2mm lead-free form factor, facilitating easy mounting on PCBs. Compatible with TTL logic, the device can withstand input voltages up to 12V regardless of the VCC voltage. Proprietary bootstrap voltage clamping technology ensures that the gate voltage of the enhanced-mode GaN FETs remains within a safe operating range. Featuring a user-friendly interface, this device further enhances the benefits of discrete GaN FETs. It serves as an ideal solution for applications requiring high-frequency, high-efficiency operation and small form factors. When paired with the TPS53632G controller, the LMG5200 can directly convert 48V to a point-of-load voltage ranging from 0.5V to 1.5V.
The advent of gallium nitride technology has significantly improved efficiency, reduced switching losses and conduction resistance, minimized heat generation, and drastically shrunk the size of fast chargers. The emergence of integrated chip packages has further enhanced integration, consolidating functions previously realized by two or three chips in traditional primary circuits into a single chip, thereby simplifying designs. Increasingly, manufacturers are investing in this domain.
As a crucial foundation for boosting or bucking applications, half-bridge circuits are widely employed in scenarios such as smartphone and laptop chargers, TVs, solar panels, data centers, and electric vehicles. With the implementation of the PD 3.1 standard, half-bridge topologies are poised to become ubiquitous in switching power supplies.
When designing PD3.1 power products, engineers opting for half-bridge integrated GaN devices instead of discrete components can effectively reduce board space occupation. Moreover, the integrated devices significantly mitigate the impact of parasitic effects on efficiency, thereby enhancing the efficiency and reliability of power products.