Patent ID: 7656262
Filing Date: 2010-02-02
Classification: H01F,H03H

Abstract:
1. A balun transformer, comprising: first to fourth layer coils stacked in that order in respective layers and coupled together magnetically, wherein, each of the layer coils has a first end and second end, the first end being the innermost end of the coil, the first end of each coil of the first to fourth layer coils is grounded, the second and third layer coils are connected in parallel, an unbalanced signal can be input or output or both to or from, respectively a common terminal of the second and third layer coils, a first balanced signal can be input or output or both to or from, respectively, the second end of the first layer coil, and a second balanced signal can be input or output or both to or from, respectively, the second end of the fourth layer coil.