Patent ID: 7573731

Claim:
A current-source push-pull DC-DC converter comprising a primary circuit and a secondary circuit divided by a transformer, wherein the primary circuit, which is a current-source push-pull circuit, comprises an input inductor L, two main switches S 1 and S 2 , and an active clamp circuit comprising two sub-switches S 3 and S 4 and clamp capacitors C c1 and C c2 ; and the secondary circuit is a full-wave output rectifier, wherein when a duty ratio of the main switches S 1 and S 2 is below 0.5, the current-source push-pull DC-DC converter operates in a non-overlapping mode while one of the main switches S 1 and S 2 is on, energy is charged in the input inductor L, and the clamp capacitor C c1 or C c2 and leakage inductances L ik1 and L ik2 of the transformer resonate.