MODE CONTROL CIRCUIT OF SEMICONDUCTOR DEVICE AND SEMICONDUCTOR MEMORY DEVICE PROVIDED WITH THE SAME

摘要

PURPOSE: A mode control circuit of a semiconductor device and a semiconductor memory device provided with the same are provided to prevent the semiconductor device from entering into a specific mode by an operator and to allow the semiconductor device to be entered into the specific mode. CONSTITUTION: A mode control circuit(101) of a semiconductor device includes a mode entering part(111) for outputting an output signal in response to an external control signal, a mode entering controller(121) for generating a mode entering allowable signal to control the semiconductor device to enter into the specific mode and a logic part(131) for generating a mode signal to set the specific mode by logically combining the output signal of the mode entering part(111) and the mode entering allowable signal. The mode entering controller(121) includes a first fuse part containing a first fuse, a second fuse part containing a second fuse and a mode entering control signal generator. The mode entering control signal generator activates the mode entering allowable signal when the first and the second fuses maintain an initial state or are changed from its initial state and deactivates the mode entering allowable signal when only one of the first and the second fuses is changed from its initial state.