A fuse device and a program transistor are connected in series with each other. A flip-flop turns ON, in response to a start signal, the program transistor to start program of the fuse device. A 2-input NAND circuit outputs an end signal at a time point where change in a resistance value of the fuse device is increased to reach a predetermined level while monitoring change in the resistance value of the fuse device through change in a voltage at a junction point of the fuse device and the program transistor. The flip-flop turns OFF, in response to the end signal, the program transistor to automatically terminate the program of the fuse device. Thus, the resistance value of the fuse device is increased to the predetermined level in a minimum program time.