According to one embodiment, a semiconductor device includes, for example, a circuit board, a plurality of elements, a plurality of controllers, and a first signal line. The elements are provided on the circuit board. The elements each include a memory. The controllers each are configured to control read of data from the memory. The controllers each are configured to control write of data into the memory. A control signal is transmitted through the first signal line. The first signal line is used in common by the controllers.