THIN FILM TRANSFORMER FOR HIGH-FREQUENCY SWITCHING POWER SOURCE AND THIN FILM INDUCTOR FOR THE SAME

摘要

PURPOSE: To realize a small size.a reduced thickness and to improve high frequency characteristics when a thin film transformer for a high-frequency switching power source and a thin film inductor are used. ;CONSTITUTION: An Si substrate is used as a substrate 10, a MOSFET for a high frequency switching power source is formed on the substrate 10 by semiconductor processing technique through an insulating layer 12b, and then a thin film transformer is manufactured by thin film forming technique. Connecting terminals 17h-17k of the transformer are connected to the MOSFET by using surface wirings on the substrate 10 and through holes formed at the insulating layers. Accordingly, wirings of wires are eliminated, an element configuration of the MOSFET and the transformer is remarkably reduced in size.thickness. Simultaneously, resistance-capacity are reduced by making the wirings minimum short, and high.frequency characteristics can be improved. Further, a reduction in noise and an improvement in an efficiency can be performed.;COPYRIGHT: (C)1994,JPO&Japio