The semiconductor device includes a fuse data storage unit, a power source signal generator and a redundancy signal generator. The fuse data storage unit generates a section signal, a fuse clock signal, a fuse reset signal and a fuse data in response to a first power-up signal generated from a power supply voltage signal. The redundancy signal generator generates a fuse set signal that is counted in response to the fuse clock signal, generates an input reset signal and an input set signal from the fuse set signal and the fuse reset signal in response to the section signal, and latches the fuse data in response to the input reset signal and the input set signal to generate a redundancy signal.