Due to the high cost and inflexibility of isolated DC/DC converter modules, many designers are choosing to implement a discrete design that is better matched to their application. In particular, the forward converter with active clamp reset has been widely used in custom supplies because of its excellent efficiency and reduced component stress. While the active clamp reset technique has advantages, it also introduces performance limitations and potential reliability concerns that have limited the scope of its use. The LTC3765/66 is a second-generation chip-set that breaks new ground by making forward converters more simple, efficient and reliable than ever before. Using Direct Flux Limit, this chipset eliminates both the reliability concerns and performance limitations of the active clamp forward converter. In addition, advanced features such as pre-bias start-up, average current limit and no-opto secondary-side control simplify a wide array of applications including isolated battery chargers.