To provide a transformer circuit by which a transformer function is obtained in a manner of on-chip without using a magnetic material such as ferrite, and to provide a method for manufacturing the same.

The transformer circuit 100 comprises first circuit wiring 2, and second circuit wiring 4 electrically insulated from the first circuit wiring 2 that can transmits an AC component of the first circuit wiring and is electrically insulated from the first circuit wiring. At least part of the second circuit wiring 4 overlaps in the vertical direction with the first circuit wiring 2 with an insulating film 3 between the two formed on the semiconductor substrate 1 so that the direction of a current flow in the second circuit wiring 4 is the same as the direction of a current flow in the first circuit wiring 2.

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