An Integrated-Stage LED Driver Based on CCM Operation of ZVDS Class-E Current-Driven Rectifier With Nonisolated Matching Network as a PFC

This article proposes a circuit analysis and design for an integrated-stage light-emitting diode (LED) driver that uses a Class-E current-driven rectifier and is connected to a Class-D LLC converter. The power switches and a dc-bus capacitor are shared. The proposed LED driver can be divided into a two-stage: the power factor correction (PFC) stage uses the output characteristics of a zero-voltage and zero-derivative-switching (ZVDS) Class-E current-driven rectifier as a power-factor corrector; in addition, this PFC stage is designed for the continuous conduction mode (CCM) operation, and the driver stage uses a zero-voltage switching Class-D LLC converter to supply a constant dc-driven current to the LED load. The circuit operation and step-by-step design of the converter are fully described. The proposed scheme works better with the CCM-ZVDS Class-E current-driven rectifier because it reduces the high current stress on the power switch caused by high di/dt. It also gets rid of the need for a differential mode input filter, and a simple non-isolated matching network without a high-frequency transformer can be used. Finally, a 150-W LED street lighting laboratory prototype is implemented, and experimental results are presented to verify the theoretical analyses of the proposed the integrated-stage LED driver.