Demonstration circuit 776 is a 36V-72Vin, 2-switch forward converter with synchronous secondary-side control featuring the LTC3705 and LTC3706. This circuit was designed specifically to attain a high stepdown ratio power supply in one stage in order to efficiently power 1.5V loads from a typical telecom input voltage range. Isolation voltage is 1500VDC. This circuit features secondary-side control of the supply without the need of an optocoupler.