According to one embodiment, there is provided a semiconductor apparatus including a first chip and a second chip. The first chip is electrically connected to a terminal to which a signal from a host device is input. The second chip is electrically connected to the first chip. The second chip has a first duty adjustment circuit. The first chip has a second duty adjustment circuit. The first duty adjustment circuit performs first calibration operation in a first period. The second duty adjustment circuit performs second calibration operation in a second period. The first period and the second period have an overlapping period.