Modified forward converter yields best in class performance for isolated DC-DC bricks

Various topologies were evaluated to provide the best performing DC-DC converter. The design goals were to provide an approach yielding the highest efficiency yet robust and low component count topology and, very fast yet very stable step load response. After a detailed evaluation, the chosen topology was a modified single-ended forward converter with a non-dissipative turn-off snubber circuit (snubber circuit) This modified forward converter operates at a duty cycle of 65% at low line (33 V) and as a result, has a very low primary current (high turns ratio in transformer). It also, has zero turn-off losses. The turn-on losses are low as well, due to the fact that the primary current is low and the leakage energy is partially recycled in a non-dissipative way and partially returned to the input voltage. One nice feature of this snubber circuit is that the transformer leakage, up to a point, "acts as your ally" in the sense that it reduces the turn on losses and minimizes EMI effects as well.