Abstract: A synchronous semiconductor memory device of the present invention has a clock generator for generating a normal and a reverse phase clocks by dividing an external clock, a command decoder for decoding an external command and outputting a command signal; latency setting means capable of selectively setting an even or odd number latency within a range of a predetermined number of clock cycles of the external clock, a latency counter which includes two counter circuits for sequentially shifting the command signal captured using the normal and reverse phase clock and being capable of switching a signal path in response to the number of clock cycles, and first and second control means which controls counting of the clock cycles equivalent to the even or odd number latency by forming an appropriate signal path.

Abstract: A calibration circuit includes: a replica buffer that drives a calibration terminal ZQ; a reference voltage generating circuit that generates a reference voltage VMID; a comparing circuit that compares a voltage appearing in the calibration terminal ZQ with the reference voltage VMID; an impedance adjusting circuit that changes an output impedance of the replica buffer based on a result of comparison carried out by the comparing circuit; and a reference voltage adjusting circuit that adjusts the reference voltage VMID. With this arrangement, the reference voltage VMID can be offset by taking into account a resistance component present between the calibration terminal ZQ and the external terminal, and therefore, a more accurate calibration operation can be carried out.

Abstract: A command control circuit includes a read-clock generation circuit that generates a read clock ICLK-R at the time of reading, a write-clock generation circuit that generates a write clock ICLK-W at the time of writing, and a burst chop AL counter that counts an additive latency of a burst chop command. The burst chop AL counter counts the burst chop command in synchronization with both the read clock ICLK-R and the write clock ICLK-W. This eliminates a need of separately arranging an AL counter that counts the burst chop command at the time of reading and an AL counter that counts the burst chop command at the time of writing.

Abstract: A semiconductor device is provided as a fuse option circuit. The semiconductor device is configured to include an input, a function selection fuse portion and a reset control circuit portion both connected to the input, and an output connected to the function selection fuse portion. The function is switched by cutting off a first fuse included in the function selection fuse portion. In addition, by cutting off a second fuse included in the reset control circuit portion, the function of the fuse option circuit can be retrieved to the function that the first fuse is not cut off. Therefore, the productivity is the same as a bonding fuse method, and the chip area can be smaller than the chip area obtained by using the bonding option scheme.

Abstract: A semiconductor device has a memory cell, decoders, a redundancy circuit and a mode setting circuit. The memory cell array has word lines including a redundant word line, bit lines and memory cells. A row decoder selects the word lines in response to a row address. Further, the row address decoder selects the redundant word line when a replacement signal is received. A column decoder selects the bit lines in response to a column address. A row address redundancy circuit stores a redundant row address. The row address redundancy circuit provides the replacement signal when the redundant row address corresponds to the received address. The mode setting circuit receives a mode signal having a normal mode and a test mode. The mode setting circuit outputs the replacement signal to the row decoder when the mode signal is in the normal mode, and prohibits an output of the replacement signal.

Abstract: A semiconductor device has a memory cell, decoders, a redundancy circuit and a mode setting circuit. The memory cell array has word lines including a redundant word line, bit lines and memory cells. A row decoder selects the word lines in response to a row address. Further, the row address decoder selects the redundant word line when a replacement signal is received. A column decoder selects the bit lines in response to a column address. A row address redundancy circuit stores a redundant row address. The row address redundancy circuit provides the replacement signal when the redundant row address corresponds to the received address. The mode setting circuit receives a mode signal having a normal mode and a test mode. The mode setting circuit outputs the replacement signal to the row decoder when the mode signal is in the normal mode, and prohibits an output of the replacement signal.

Abstract: Disclosed is a synchronous semiconductor device including clock generation circuit that frequency divides a clock signal (PCLK) input from an input buffer and generates first and second internal clock signals having a predetermined phase difference from first and second frequency-divided clock signals of different phases, respectively, a first input circuit control unit that receives a chip select signal and samples the chip select signal in synchronization with the clock signal, second and third input circuit control units that sample an output of the first input circuit control unit in synchronization with the first and second internal clock signals, respectively, and first and second input circuits that receive a result of a logic operation between the output of the first input control unit and an output of the second input circuit control unit and a result of a logic operation between the output of the first input circuit control unit and an output of the third input circuit control unit as input enable s

Abstract: A synchronous semiconductor memory device of the present invention has a clock generator for generating a normal and a reverse phase clocks by dividing an external clock, a command decoder for decoding an external command and outputting a command signal; latency setting means capable of selectively setting an even or odd number latency within a range of a predetermined number of clock cycles of the external clock, a latency counter which includes two counter circuits for sequentially shifting the command signal captured using the normal and reverse phase clock and being capable of switching a signal path in response to the number of clock cycles, and first and second control means which controls counting of the clock cycles equivalent to the even or odd number latency by forming an appropriate signal path.

Abstract: Disclosed is a delay adjustment circuit including a first set of transistors, which are connected between a PMOS transistor forming an inverter and a power supply in parallel and have gates supplied with control signals, respectively, a second set of transistors which are connected between an NMOS transistor forming the inverter, and the ground GND, in parallel and have gates supplied with control signals, respectively, and another inverter receiving an output of the inverter as an input. At least one of the transistors of the first set of transistors and at least one of the transistors of the second set of transistors are set in an on-state.

Abstract: A semiconductor device has a memory cell, decoders, a redundancy circuit and a mode setting circuit. The memory cell array has word lines including a redundant word line, bit lines and memory cells. A row decoder selects the word lines in response to a row address. Further, the row address decoder selects the redundant word line when a replacement signal is received. A column decoder selects the bit lines in response to a column address. A row address redundancy circuit stores a redundant row address. The row address redundancy circuit provides the replacement signal when the redundant row address corresponds to the received address. The mode setting circuit receives a mode signal having a normal mode and a test mode. The mode setting circuit outputs the replacement signal to the row decoder when the mode signal is in the normal mode, and prohibits an output of the replacement signal.

Abstract: A semiconductor device is provided as a fuse option circuit. The semiconductor device is configured to include an input, a function selection fuse portion and a reset control circuit portion both connected to the input, and an output connected to the function selection fuse portion. The function is switched by cutting off a first fuse included in the function selection fuse portion. In addition, by cutting off a second fuse included in the reset control circuit portion, the function of the fuse option circuit can be retrieved to the function that the first fuse is not cut off. Therefore, the productivity is the same as a bonding fuse method, and the chip area can be smaller than the chip area obtained by using the bonding option scheme.

Abstract: There is provided a fuse detection circuit comprising a first inverter circuit comprising a PMOS transistor (P2) and an NMOS transistor (N2) having gates connected in common and connected to the first node (A); a second inverter circuit comprising a PMOS transistor (P1) and an NMOS transistor (N1) having gates connected in common and connected to the second node (B); and a third NMOS transistor (N3) having a drain and source connected between the third node (C) and the ground potential, and a gate connected with the control signal, wherein the control signal is set to a predetermined level in an initial state to precharge the node (A),(B) and thereafter a molten state of a fuse is detected in accordance with a potential level of the second node (B) at a change in the level of the control signal.

Abstract: There is provided a fuse detection circuit comprising a first inverter circuit comprising a PMOS transistor (P2) and an NMOS transistor (N2) having gates connected in common and connected to the first node (A); a second inverter circuit comprising a PMOS transistor (P1) and an NMOS transistor (N1) having gates connected in common and connected to the second node (B); and a third NMOS transistor (N3) having a drain and source connected between the third node (C) and the ground potential, and a gate connected with the control signal, wherein the control signal is set to a predetermined level in an initial state to precharge the node (A),(B) and thereafter a molten state of a fuse is detected in accordance with a potential level of the second node (B) at a change in the level of the control signal.

Abstract: The period of time required for a parallel test can be shortened by widening the application range of the parallel test. In the semiconductor memory device having memory cell portions, there are provided a column controller that simultaneously activates a plurality of columns which are subject to degenerate substitution in a column redundant substitution; and a data read-out circuit that simultaneously reads out the data from a plurality of memory cells as selected by the above plurality of columns.

Abstract: The period of time required for a parallel test can be shortened by widening the application range of the parallel test. In the semiconductor memory device having a memory cell portions (5-A, 5-B), there are provided a column control means (1˜4) for simultaneously activating a plurality of columns which are subject to the degenerate substitution in the column redundant substitute; and a data read-out means (6-A, 6-B, SDBP-B0, SDBP-B1, and 9) for simultaneously reading out the data from a plurality of memory cells as selected by the above plurality of columns.

Abstract: A semiconductor memory device includes a semiconductor substrate having a memory cell array area, a peripheral circuit area surrounding the memory cell array area, and a boundary area located between the memory cell array area. The peripheral circuit area, the memory cell array area, and the boundary area are located on a principle surface of the semiconductor substrate. The device also includes word lines which extend parallel to each other in a first direction, a dummy word line which extends in the first direction, and an insulation layer covering over the word lines and the dummy word line. The device further includes bit lines and a dummy bit line respectively formed over the insulation layer and extending parallel to each other in a second direction substantially perpendicular to the first direction. Memory cells are located in the memory cell array area at intersections of the word lines and the bit lines, each of which includes a capacitor and a switching transistor.