Primary-Side Control for Flyback Converter with Wide Range Operation

摘要

Most of current primary side regulation (PSR) control methods are implemented in either discontinuous conduction mode (DCM) or continuous conduction mode (CCM). Because of the difficulty in sensing the output voltage, no algorithm is suitable for both DCM and CCM, and the power range of the system is limited. The proposed controller is suitable for both DCM and CCM with wide power range operation. The “TSMC 0.25 μm CMOS high voltage mixed signal process” is adopted to implement the proposed IC. A flyback converter with 400 V input and 20 V/150 W output is built to verify the feasibility of proposed control IC.