Function Blocks of a Highly-Integrated All-in-GaN Power IC for DC-DC Conversion

GaN-on-Si technology is on the advance for the use in power ICs thanks to wide bandgap performance combined with a lateral structure and a low-cost carrier substrate. A common GaN power IC platform with several active and passive devices, as well as analog and digital circuits is presented. This platform is used to integrate periphery function blocks of power electronics circuits, such as driving, sensing, protection, and control. In detail, an efficient GaN-based gate driver with integrated bootstrap capacitances is realized, which has a current consumption of only 2.2 mA at a supply voltage of 5 V and a switching frequency of 1 MHz. Furthermore, a GaN-based voltage mode control is described based on a PWM generator with error amplifier and verified with measurements. Finally, the circuit design of an all-in-GaN power IC for DC-DC conversion with half-bridge, driver, level shifter, dead time and voltage mode control is presented. With small additional chip area, further function blocks can be integrated to the power device(s) to realize a modern highly-efficient and highly-functional GaN-based conversion component for the next generation of power electronics.