A new generation of power electronic systems with reduced losses, size and costs is emerging due to the rapid development of gallium nitride (GaN) transistors. These transistors are fabricated in the GaN-on-Si technology and have a lateral structure, which enables the monolithic integration with peripheral functions such as gate driver, sensing, protection, and even control. This research work extends the monolithic integration in the GaN technology by introducing and investigating devices, buildings, and function blocks towards a new category of highly functional GaN power ICs for low-cost high-efficient switching regulator applications. Integration levels are introduced for the classification of GaN power ICs. A GaN power IC platform with devices as well as building blocks is investigated regarding its characteristics and its related design issues are analyzed. Thereby, the devices are divided into active and passive and the function blocks into digital and analog. Based on this GaN power IC platform, two case studies are presented for a DC-DC synchronous buck converter and AC-DC active rectifier diode, which contributes to efficient, cost-effective and more sustainable power electronic products using functional integration in GaN.weiterlesen