Abstract: A circuit and a method for controlling a write recovery time (tWR) in a semiconductor memory device are disclosed. The method according to one embodiment of the present invention includes receiving an automatic precharge write command, and generating a tWR control signal, which is delayed from a point in time when the automatic precharge write command is received to a point in time when a last data segment is written in the semiconductor memory device. Therefore, power consumption and clock noise may be reduced since an operation of a counter in the circuit for controlling the tWR may be minimized after a point in time when the last data is written.

Abstract: A semiconductor memory device includes both a data redundancy memory cell array and a local redundancy memory cell array. Cells of the data redundancy memory cell array and/or cells the local redundancy memory cell arrays may be substituted for one or more defective cells of a normal memory cell array, depending on the number of defects generated in the normal memory cell array. An embodiment of a semiconductor memory device may include a plurality of normal memory blocks, each normal memory block comprising a normal memory cell array and a local redundancy memory cell array, at least one data line redundancy memory block, each data line redundancy memory block comprising a data redundancy memory cell array, and a redundancy controller to substitute columns of the data line redundancy memory cell array for some columns of at least two columns in each normal memory cell array, and to substitute columns of the local redundancy memory cell array for the remaining columns of the at least two columns.

Abstract: A substrate voltage generating circuit for use in a semiconductor memory device is provided. The semiconductor memory device includes a charge pump for generating a substrate bias voltage in response to a clock signal; a first inverter type detector for detecting whether the substrate bias voltage reaches a target voltage; a second differential amplifier type detector for detecting whether the substrate bias voltage reaches the target voltage; and a driver for generating the clock signal in response to an output of one of the first and second detectors.

Abstract: A circuit and a method for controlling a write recovery time (tWR) in a semiconductor memory device are disclosed. The method according to one embodiment of the present invention includes receiving an automatic precharge write command, and generating a tWR control signal, which is delayed from a point in time when the automatic precharge write command is received to a point in time when a last data segment is written in the semiconductor memory device. Therefore, power consumption and clock noise may be reduced since an operation of a counter in the circuit for controlling the tWR may be minimized after a point in time when the last data is written.

Abstract: A substrate voltage generating circuit for use in a semiconductor memory device is provided. The semiconductor memory device includes a charge pump for generating a substrate bias voltage in response to a clock signal; a first inverter type detector for detecting whether the substrate bias voltage reaches a target voltage; a second differential amplifier type detector for detecting whether the substrate bias voltage reaches the target voltage; and a driver for generating the clock signal in response to an output of one of the first and second detectors.