Analysis and Development of LED Based Current Sensing Techniques for Gallium Nitride (GaN) Power Transistors

open_access
Open Access
Author:
Gadagkar, Adarsh
Graduate Program:
Electrical Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
June 18, 2026
Committee Members:
Yunting Liu, Thesis Advisor/Co-Advisor
Rongming Chu, Committee Member
John Doherty, Professor in Charge/Director of Graduate Studies
Keywords:
Current Sensor
Gallium Nitride (GaN)
Analog Design
Power Electronics
Overcurrent Protection
Amplifiers
integrated circuit design
Abstract:
From being able to alert overcurrent events to save valuable and expensive electrical systems to being able to optimize a control system through current monitoring, current sensors serve as a critical piece of modern power electronics systems. As a result, there is a growing amount of research with the purpose of obtaining higher bandwidths, lower power consumptions, and utilizing smaller devices to optimize a given current sensor. Modern Gallium Nitride (GaN) power devices offer considerable improvements in switching speed, low on-resistance (RON), making them popular choices within the realm of power electronics. In this thesis, two current sensor designs are discussed, one using silicon-based commercial components, and the other using GaN devices monolithically integrated with other power GaN transistors. The current sensor designs both utilize amplifiers, with the GaN-based amplifier showing considerable improvements in bandwidth and power consumption. The design using commercially available Silicon-based components was fabricated onto a single PCB and experimentally validated. The GaN-based design will be fabricated onto a single die and was validated on the simulation. The current sensor will ultimately drive an LED emitter which will be connected to a receiver through an optical fiber to maximize transmission speed to the ultimate external controller. The silicon-based design exhibited a power consumption of about 100mW and a bandwidth of 15kHz, whereas the GaN-based solutions consume less than 50mW and the simulated bandwidth is larger than 300kHz.