US Patent 7421636 Semiconductor memory device having a test control circuit

A semiconductor memory device having a test control circuit includes a cell array, a BIST (built-in self test) circuit adapted and configured to perform a BIST operation on the cell array, a BISR (built-in self repair) circuit adapted and configured to perform a BISR operation on the cell array, and a command decoder adapted and configured to generate a first control signal for selecting a BIST operation by the BIST circuit or a test by an external tester and a second control signal for controlling a BISR operation by the BISR circuit. As a result, a test by an external tester, a BIST (built-in self test) and a BISR (built-in self repair) are individually performed in response to an additional command signal.