A Highly Linear Integrated Temperature Sensor on a GaN Smart Power IC Platform

On a GaN smart power integrated circuit (IC) platform, a highly linear (i.e., proportional to absolute temperature) temperature sensor IC is demonstrated for building voltage references as well as temperature compensation functional blocks. The circuit is designed based on the temperature-dependent characteristics of GaN-based peripheral devices (e.g., heterojunction Schottky barrier diode, enhancement-/depletion-mode high electron mobility transistors, and lateral field-effect rectifiers) that are monolithically integrated with high-voltage power devices. This monolithic integration scheme facilitates the design efforts in taking full advantages of GaN's superior capability to operate at high temperatures. Proper circuit operation was demonstrated at 275 degrees C.