INSULATING TRANSFORMER

An insulating transformer includes an insulation layer, a transformer embedded in the insulation layer, and a capacitor. The transformer includes first and second coils. The first coil includes a first signal terminal and a first ground terminal. The second coil is separated from the first coil in a thickness direction of the insulation layer and includes a second signal terminal and a second ground terminal. The capacitor includes first and second capacitor electrodes. The first capacitor electrode is connected to the first ground terminal of the first coil. The second capacitor electrode is located between the first capacitor electrode and the second coil and connected to the second ground terminal of the second coil. The insulating transformer further includes a first insulation film located between the first coil and the first capacitor electrode, and a second insulation film located between the second coil and the second capacitor electrode.