Common integrated GaN power stage solutions
Currently, many integrated GaN power stage solutions are available on the market, such as Infineon CoolGaN™ Drive, onsemi Vertical GaN (GaN‑on‑GaN), and TI GaN Power Stages (LMG36xx / LMG26xx / LMG34xx). Each solution has its own technical approach and positioning; the following sections explain their differences and application orientations.
Comparison of key performance indicators of new generation silicon, gallium nitride (GaN), and silicon carbide (SiC) technologies, and their relevance to basic switching operations (From Infineon)
The core positioning of Infineon’s CoolGaN™ Drive series is an integrated gate driver power stage solution based on Infineon’s own CoolGaN™ GaN transistors, aimed at simplifying design and enhancing performance in medium to high-voltage power and inverter applications. The CoolGaN™ Drive series offers single-switch and half-bridge devices in the 600 - 700 V class, integrating GaN FETs with smart gate drivers in a single package. Features include adjustable dv/dt, built-in protection (OCP, OTP, SCP, etc.), and some models also integrate lossless current sense, aiding current detection and protection functions. The integrated driver and package design significantly reduce parasitic inductance and EMI risks, improving system stability and efficiency.
Schematic diagram of a half-bridge LLC (From Infineon)
Application scenarios for Infineon’s CoolGaN™ Drive series include medium to high-voltage AC/DC conversion (e.g., adapters, power tool chargers, industrial power supplies), and typical medium-frequency (greater than 200 kHz) power topologies. Advantages of the CoolGaN™ Drive series include ease of design, BoM reduction, high power density and efficiency, good protection and robustness, and availability in half-bridge configurations suitable for Totem-Pole PFC, LLC, and other topologies.
onsemi’s Vertical GaN is not simply an integrated driver power stage but a next-generation power device architecture. Its GaN layer is grown directly on a GaN substrate, allowing current to flow vertically through the chip (from top to bottom), differing from traditional lateral GaN HEMTs. This vertical current flow structure enables higher voltage withstand capability, higher current capacity, and lower thermal resistance. It is expected to achieve higher power density and efficiency than lateral GaN, offering advantages in AI data centers, electric vehicle inverters, and high-power DC-DC applications, targeting voltages up to 1200 V or higher, expanding into the voltage class of wide-bandgap devices like SiC.
3D structure of Vertical GaN (From onsemi)
While conventional lateral GaN (CoolGaN™, TI LMG series, etc.) primarily targets low to medium voltage ranges (typically under 800 V), Vertical GaN aims to fill the high-voltage (greater than 1 kV) segment, offering superior power density and heat dissipation. Key applications include 800 V DC-DC conversion in data centers, electric vehicle motor drives, large-scale energy storage, and renewable energy systems.
TI’s LMGxx series are integrated GaN power stages, combining GaN FETs, gate drivers, protection functions (UVLO/OCP/OTP), and current sensing devices in one package, representing typical “half-bridge power stages.” The LMGxx series includes different sub-families, such as LMG26xx/LMG36xx/LMG34xx. LMG26xx series supports 650 V GaN half-bridges with built-in drive and current sensing, suitable for medium-frequency switching power supplies. The LMG36xx series (e.g., LMG3622/LMG3624/LMG3626) are 700 V types, integrating GaN FETs and drivers, supporting adjustable switching slew rate control to mitigate EMI and ringing issues, and featuring built-in OCP, OTP, UVLO, and low quiescent current design. The LMG34xx is another GaN power stage product line, usable with TI evaluation boards for rapid high-frequency performance testing.
LMG2610 Simplified Block Diagram (From TI)
Technical highlights of TI’s LMGxx series include integrated current sensing to reduce external sensing components, configurable switching slew rate for EMI/ringing control, and high integration simplifying PCB layout and reducing parasitic effects. Typical applications include AC/DC and DC/DC converters, USB-PD chargers, PFC/LLC converters, and industrial power supplies.
Overall, Infineon’s CoolGaN™ Drive focuses on “ease of use and integration,” lowering the design threshold and accelerating GaN adoption. onsemi’s Vertical GaN targets the high-voltage and high-current market as a next-generation GaN architecture aiming to surpass the limitations of existing lateral devices. TI’s LMG series represents mature GaN power stage product lines, offering systematic, highly integrated solutions supporting various standard power conversion applications.
Related information：
- Key technologies and design approaches for integrated GaN gate drive power stages
- Key technologies and design paths for upgrading to integrated GaN power stages
- Integrated GaN power stages add smart protection and sensing functions
- Integrated GaN power stage solutions with protection and sensing functions