LT8418 100 V Half-Bridge GaN Driver

ADI's LT8418 is a 100 V half-bridge GaN driver integrating top and bottom driver stages, driver logic control, and protections. It can be configured into synchronous half-bridge and full-bridge topologies or buck, boost, and buck-boost topologies. The LT8418 provides strong current sourcing/sinking capability with 0.6 Ω pull-up and 0.2 Ω pull-down resistance. It integrates a smart integrated bootstrap switch to generate a balanced bootstrap voltage from V_CC with a minimum dropout voltage.

The LT8418 provides split gate drivers to adjust the turn-on and turn-off slew rates of GaN FETs to suppress ringing and optimize EMI performance. All driver inputs and outputs have a default low state to prevent GaN FETs from being falsely turned on. The LT8418, INT, and INB inputs are independent and TTL logic compatible. Meanwhile, the LT8418 performs with a fast propagation delay of 10 ns and maintains an excellent delay matching of 1.5 ns between the top and bottom channels, making it suitable for high-frequency DC/DC converters, motor drivers, and class-D audio amplifiers. In addition, the LT8418 employs the WLCSP package to minimize parasitic inductance, enabling its wide use in high-performance and high-power density applications.

The EVAL-LT8418-BZ evaluation circuit features the LT8418 driving two 100 V enhanced gallium nitride (eGaN) FETs in a half-bridge configuration. The circuit is optimized as a buck converter but can be used as a boost converter or other converter topologies consisting of a half-bridge. The evaluation circuit can deliver up to 10 A with good thermal management.