Patent ID: 7825535
Filing Date: 2010-11-02
Classification: H02M,Y02B

Abstract:
1. A self-coupled transformer boostbuck circuit used in a LLC converter, comprising: a first transformer, said first transformer having a primary side and a secondary side said primary side comprising a first winding, said secondary side comprising a second winding and a third winding, said second winding and said third winding being connected in series, the connection between said second winding and said third winding being connected to ground potential, said first winding having one end coupled to the output terminal of said LLC converter; a first switch said first switch having one end coupled to one end of said second winding that has an opposite end providing with an opposite end of said first switch a first voltage output (V a second switch, said second switch having one end coupled to one end of said third winding opposite to said second winding and an opposite end coupled to one end of said first switch opposite to said second winding; a second transformer, said second transformer comprising a first winding, a second winding, a third winding, a fourth winding, a fifth winding and a sixth winding that are connected in series the first winding of said second transformer having one end coupled to the second winding of said first transformer, the sixth winding of said second transformer having an opposite end coupled to one end of said third winding opposite to said second winding, the connection between the third winding and fourth winding of said second transformer being connected to ground potential; a third switch, said third switch having one end coupled to the connection between the first winding and second winding of said second transformer and an opposite end providing a second voltage output (V a fourth switch, said fourth switch having one end coupled to the connection between the second winding and third winding of said second transformer; a fifth switch, said fifth switch having one end coupled to the connection between the fourth winding and fifth winding of said second transformer and an opposite end coupled to an opposite end of said fourth switch and providing a third voltage output (V a sixth switch, said sixth switch having one end coupled to the connection between the fifth winding and sixth winding of said second transformer and an opposite end connected to the second voltage output end of said third switch such that said second voltage output and said third voltage output are not affected by variation of said first voltage output.