Demonstration circuit 1143 is a 20W isolated flyback converter with synchronous rectification and primary-side regulation featuring the LT3825. The circuit was designed to demonstrate the high levels of performance, efficiency and small solution size attainable using this part in a flyback power supply. It operates at 250kHz and produces a regulated 3.3V, 6A output from an input voltage range of 36V to 72V: suitable for telecom and other applications. It has a footprint area that is 1.0 inch square. Synchronous rectification helps to attain efficiency exceeding 88%. Isolation voltage is 1500VDC.