A multilayer electronic component including a resin layer disposed on a mounting board side is mounted on a mounting board, and has a structure such that, even when deformation, such as deflection and strain, occurs, a stress on the multilayer electronic component is relieved. The PTA includes a Parallel Test Bus, a test controller connected to the PTB, and a plurality of addressable PTB controllers connected to the PTB, in which each addressable PTB controller is coupleable to a respective electronic circuit to be accessed. When closed or activated, the switch in the startup circuit charges an energy storing device in the power converter.