According to the laminated circuit board device having the above configuration, a vacant space can be formed between the branching portions and the merging portions between the first circuit pattern and the second circuit pattern. Therefore, another circuit can be disposed in the vacant space, or the electronic component can be disposed. In addition, since the sum of the pattern widths is the same in the first circuit pattern and the second circuit pattern, the distribution of the current flowing in the first circuit pattern and the distribution of the current flowing in the second circuit pattern can be easily aligned. That is, the induction magnetic field generated by the current change of the first circuit pattern and the induction magnetic field generated by the current change of the second circuit pattern can be aligned.

One end of the first circuit pattern and one end of the second circuit pattern are configured to be connectable to a common power source (21) or a common load via a common circuit (via 13) one end side, and the other end of the first circuit pattern and the other end of the second circuit pattern may be configured to be connectable to a common load (24) or a common power source via a common circuit (via 14) on the other end side.

According to the laminated circuit board device having the above configuration, one end of the first circuit pattern and one end of the second circuit pattern can be connected to a common power source or a common load by the one end side common circuit. Further, the other end of the first circuit pattern and the other end of the second circuit pattern can be connected to a common load or a common power source by the other end side common circuit. Therefore, it is easy to supply a common current to the first circuit pattern and the second circuit pattern.