Semiconductor device having chip selection circuit and method of generating chip selection signal

A method of generating a chip selection signal to activate a predetermined circuit in a semiconductor memory device having a plurality of data input buffer circuits, the method comprising:

• generating a first control signal in response to an address and a command input from outside the semiconductor memory device;
• generating a second control signal to activate the plurality of data input buffer circuits in response to the first control signal;
• and
• generating a chip selection signal to activate the predetermined circuit when at least one of output signals of the plurality of data input buffer circuits is in a first logic state.

A semiconductor memory device comprising:

• a programming register to generate an output signal in response to at least one input;
• an input buffer control circuit to generate a buffer activation signal in response to the output signal of the programming register;
• a plurality of data input buffer circuits to receive the buffer activation signal, which selects at least one of the data input buffer circuits to generate a buffer output signal;
• a chip selection circuit to receive the buffer output signal and to activate a defect detecting and repair circuit when at least one of the buffer output signals is in a first logic state.