| 摘要 |
PURPOSE:To obtain a step-up transformer which can be miniaturized with excellent characteristics by burying a transfer coil into a nonmagnetic substrate at a part corresponding to the lower part of a transfer core part and forming a transfer coil of a thin film on the flat surface of the substrate. CONSTITUTION:A nonmagnetic substrate 1 contains a lower coil 2 at the primary side (head side), a lower coil 3 at the secondary side, a lower insulated film 4, a transfer coil 5, an upper insulated film 6, an upper coil 7 at the primary side and an upper coil 8 at the secondary side. The coils 2 and 3 are buried into the substrate 1, and the substrate 1 has a flat surface. Owing to this flat surface of the substrate 1, a soft magnetic film forming the core 5 on the substrate 1 has excellent characteristics. Furthermore the coil 2 has a sufficient sectional area of 100mum width and several 10mum thickness of the film. Thus the signal loss can be minimized. |
