| abstract |
According to the present invention an electronic device, which is to be installed in an engine room, comprises a circuit board 11, electronic elements, which are carried by the circuit board 11 and function when electricity is applied from the circuit board 11 to them, a case 3 that accommodates the circuit board 11 on which the electronic elements are disposed, and a cover 6 that covers an opening of the case 3, the entire surface of a conductor pattern formed of a conductive material on the circuit board is covered with a barrier metallic film made of a metal other than the metal of the conductive material having a property of mutual diffusion with a solder material, and the barrier metallic film is further covered with a protective insulating film. |