The task of the present invention is to enhance safety of an insulation-type DC/DC converter.
The present invention relates to an insulation-type DC/DC converter, an AC/DC converter, a power adapter and an electronic device. A switch transistor is disposed on a primary side of a transformer, and a synchronous rectification transistor is disposed on a secondary side of the transformer. A primary-side control portion performs switch-driving of the switch transistor, and a secondary-side control portion controls turn-on and turn-off of the synchronous rectification transistor. A pulse transformer portion for implementing bi-directional communication between the primary-side control portion and the secondary-side control portion is disposed between the primary side and the secondary side. For example, signals associated with turn-on and turn-off of the switch transistor are transceived between the primary-side control portion and the secondary-side control portion by a pulse transformer portion.