With the advent of reliable, high brightness and high efficacy LEDs, the lighting industry is expected to see a significant growth in the near future. However, for LEDs to completely replace the traditional incandescent and CFL bulbs, the power converters within the LED drivers need to be miniaturized. Superior figure of merit (R ds,ON xQ g ) of Gallium Nitride (GaN) FETs over Silicon FETs [1] can enable both high efficiency and high frequency operation, thereby making power converters smaller, more efficient and reliable. By using integrated controllers and drivers, the number of components on the driver PCB can be reduced, further miniaturizing the driver. This work focuses on demonstrating a small form factor, high efficiency offline LED driver using GaN FETs with an integrated gate driver and controller circuit implemented on a 0.35μm CMOS process with 3.3V/15V voltage handling capability.
['Saurav Bandyopadhyay', 'Bob Neidorff', 'Dave Freeman', 'Anantha P. Chandrakasan']
90.6% efficient 11MHz 22W LED driver using GaN FETs and burst-mode controller with 0.96 power factor