A driver board comprising a driver circuit which is mounted thereon, and that is configured to drive a switching element of a power converter, the driver board further comprising: an insulating board formed in a flat plate shape; a transformer that is configured to convert an input primary side voltage to a secondary side voltage for driving the switching element; a power supply control IC that is configured to control a current input to the transformer; a primary side circuit (112, 112a, 112b) that is mounted on each of a first circuit region and a second circuit region and uses the primary side voltage as a power supply, the first circuit region being on one surface of the insulating board, the second circuit region being provided on another surface of the insulating board and facing the first circuit region via the insulating board; a secondary side circuit (113, 113a, 113b) that is mounted on each of a third circuit region and a fourth circuit region, includes the driver circuit, and uses the secondary side voltage as a power supply, the third circuit region being adjacent to the first circuit region via a first insulating region on the one surface, the fourth circuit region being adjacent to the second circuit region via a second insulating region on the other surface; a first through hole that penetrates the insulating board and electrically connects the primary side circuit (112, 112a, 112b) on the first circuit region to the primary side circuit (112, 112a, 112b) on the second circuit region; and a second through hole that penetrates the insulating board and electrically connects the secondary side circuit on the third circuit region to the secondary side circuit (113, 113a, 113b) on the fourth circuit region, wherein the transformer is configured, so as to cross the first insulating region, such that a primary side terminal (114a, 115a) is connected to the primary side circuit (112, 112a, 112b) provided on the first circuit region and a secondary side terminal (114b, 115b) is connected to the secondary side circuit (113, 113a, 113b) provided on the third circuit region, the power supply control IC is configured, so as to cross the second insulating region, such that a primary side terminal (114a, 115a) is connected to the primary side circuit (112, 112a, 112b) provided on the second circuit region and a secondary side terminal (114b, 115b) is connected to the secondary side circuit (113, 113a, 113b) provided on the fourth circuit region, and the first insulating region and the second insulating region are formed so as to at least partially face each other via the insulating board such that the first circuit region and the fourth circuit region do not face each other via the insulating board and the second circuit region and the third circuit region do not face each other via the insulating board. an insulating board formed in a flat plate shape; a transformer that is configured to convert an input primary side voltage to a secondary side voltage for driving the switching element; a power supply control IC that is configured to control a current input to the transformer; a primary side circuit (112, 112a, 112b) that is mounted on each of a first circuit region and a second circuit region and uses the primary side voltage as a power supply, the first circuit region being on one surface of the insulating board, the second circuit region being provided on another surface of the insulating board and facing the first circuit region via the insulating board; a secondary side circuit (113, 113a, 113b) that is mounted on each of a third circuit region and a fourth circuit region, includes the driver circuit, and uses the secondary side voltage as a power supply, the third circuit region being adjacent to the first circuit region via a first insulating region on the one surface, the fourth circuit region being adjacent to the second circuit region via a second insulating region on the other surface; a first through hole that penetrates the insulating board and electrically connects the primary side circuit (112, 112a, 112b) on the first circuit region to the primary side circuit (112, 112a, 112b) on the second circuit region; and a second through hole that penetrates the insulating board and electrically connects the secondary side circuit on the third circuit region to the secondary side circuit (113, 113a, 113b) on the fourth circuit region, wherein the transformer is configured, so as to cross the first insulating region, such that a primary side terminal (114a, 115a) is connected to the primary side circuit (112, 112a, 112b) provided on the first circuit region and a secondary side terminal (114b, 115b) is connected to the secondary side circuit (113, 113a, 113b) provided on the third circuit region, the power supply control IC is configured, so as to cross the second insulating region, such that a primary side terminal (114a, 115a) is connected to the primary side circuit (112, 112a, 112b) provided on the second circuit region and a secondary side terminal (114b, 115b) is connected to the secondary side circuit (113, 113a, 113b) provided on the fourth circuit region, and the first insulating region and the second insulating region are formed so as to at least partially face each other via the insulating board such that the first circuit region and the fourth circuit region do not face each other via the insulating board and the second circuit region and the third circuit region do not face each other via the insulating board.