A semiconductor device includes a decoder configured to receive an extended mode register set (EMRS) code including specific information, and decode the received EMRS code to acquire the specific information; a peripheral controller configured to generate a control signal based on the specific information; and a peripheral region including a plurality of buffers, the plurality of buffers being configured to be controlled by the control signal, wherein the specific information includes information indicating an expected bandwidth of input data that is to be input to one of the plurality of buffers.