Abstract: The present invention efficiently decides line failure and contact failure in a semiconductor device. The semiconductor device has a plurality of bit line groups in which connection with local I/O lines is controlled by the same column selection signal line. A failure detecting circuit compares a first data group read from a first bit line group and a second data group read from a second bit line group to detect whether or not connection failure (contact failure) with the column selection signal line occurs in one of the first and second bit line groups.

Abstract: To provide a semiconductor device including a pair of antifuse elements at either a high level or a low level, an OR circuit that outputs different logic information for a case that at least one of the antifuse elements is at a high level and a case that both of the antifuse elements are at a low level, and an exclusive OR circuit that outputs different logic information for a case that the logic states are different from each other and a case that they are same as each other.

Abstract: A memory module includes a plurality of memory chips, a plurality of data register buffers, and a command/address/control register buffer mounted on a module PCB. The data register buffers perform data transfers with the memory chips. The command/address/control register buffer performs buffering of a command/address/control signal and generates a control signal. The buffered command/address/control signal is supplied to the memory chips, and the control signal is supplied to the data register buffers. According to the present invention, because line lengths between the data register buffers and the memory chips are shortened, it is possible to realize a considerably high data transfer rate.

Abstract: For example, four driver transistors are arranged in wells so as to adjoin both sides of each of two element isolation regions. Two pairs of cross-coupled sense transistors are arranged in the wells at positions farther from the element isolation regions than the driver transistors are. Such an arrangement provides more than a certain distance between the sense transistors and the respective corresponding element isolation regions. This reduces the effect of a phenomenon that threshold of a transistor varies according to a distance from an element isolation region. As a result, it is possible to exactly match the characteristics of each pair of cross-coupled transistors.

Abstract: A method includes issuing a calibration command and performing a calibration operation in response to the calibration command. The calibration operation includes adjusting an impedance of a first replica buffer with updating a first code, the first replica buffer being substantially identical in circuit configuration to one of pull-up and pull-down circuits included in an output buffer, adjusting impedance of a second replica buffer with updating a second code, the second replica buffer being substantially identical in circuit configuration to the other of the pull-up and pull-down circuits included in the output buffer, controlling a first latch circuit to hold the first code when the impedance of the first replica buffer reaches a first level, and controlling a second latch circuit to hold the second code when the impedance of the second replica buffer reaches a second level.

Abstract: Disclosed herein is a semiconductor device having a self-refresh mode in which a refresh operation of the storage data is performed. The semiconductor device activates an input buffer circuit that receives an impedance control command to control an impedance of the data terminal even in the self-refresh mode so that the semiconductor device can change an impedance of the data terminal during the self-refresh mode.

Abstract: Disclosed herein is an information processing system having first and second devices. The second device alternately issues a self-refresh command and a self-refresh exit command to the first device. The first device performs a refresh operation once in response to the self-refresh command and updates a state of a DLL circuit in response to the self-refresh exit command.

Abstract: Disclosed herein is a semiconductor device having first and second operation modes. In the first operation mode, the semiconductor device deactivates a DLL circuit during a self-refresh mode. In the second operation mode, the semiconductor device intermittently activates the DLL circuit to generate an internal clock signal.

Abstract: Disclosed herein is a semiconductor device having self-refresh modes in which a refresh operation of storage data is periodically performed asynchronously with an external clock signal. The semiconductor device performs the refresh operation on n memory cells in response to an auto-refresh command. The semiconductor device periodically performs the refresh operation on m memory cells included in the memory cell array during the self-refresh mode, where m is smaller than n.

Abstract: To include an AL counter that outputs a second ODT signal after counting a clock signal by an additive latency after receiving a first ODT signal, and a counter control circuit that controls the AL counter such that the second ODT signal having the same logic value as a logic value of the first ODT signal at a time of shifting from an asynchronous mode to a synchronous mode is output during a period until when at least the clock signal is input by an additive latency after the shifting. With this configuration, an interruption of an CDT operation can be prevented without separately providing a CKE counter. Therefore, the circuit scale can be reduced and the power consumption can be also reduced.

Abstract: To include a power-down control circuit that suspends an operation of a predetermined internal circuit in response to a power-down command, and an external terminal to which a selection signal is input from outside simultaneously with issuance of a power-down command. The power-down control circuit suspends an operation of a DLL circuit when the selection signal is at a low level, and continues an operation of the DLL circuit when the selection signal is at a high level. According to the present invention, by using the selection signal input simultaneously with a power-down command, mode selection can be made on-the-fly.

Abstract: To include a first replica buffer that has substantially the same circuit configuration as a pull-up circuit which constitutes an output buffer and a second replica buffer that has substantially the same circuit configuration as a pull-down circuit which constitutes the output buffer. When a first calibration command ZQCS is issued, either a control signal ACT1 or ACT2 is activated, and a calibration operation is performed for either the first replica buffer or the second replica buffer. When a second calibration command ZQCL is issued, both of the control signals ACT1, ACT2 are activated and the calibration operation is performed for both the first replica buffer and the second replica buffer.

Abstract: A latency counter includes a counter circuit and a point-shift FIFO circuit. Latch circuits included in the point-shift FIFO circuit are divided into n groups having wired-OR outputs, and an output of a latch circuit that belongs to a group different from a current group is selected each time a count value is updated.

Abstract: To include two counter circuits that change impedances of two replica circuits, respectively, and an impedance adjustment control circuit that controls the counter circuits to update count values of the counter circuits. The impedance adjustment control circuit controls one of the counter circuits to finish updating the count value of the counter circuit in response to a change of the impedance of the corresponding replica circuit from a state of being lower than an impedance of an external resistor to a state of being higher than the impedance of the external resistor, and controls the other counter circuit to finish updating the count value of the other counter circuit in response to a change of the impedance of the other replica circuit from a state of being higher than the impedance of the former replica circuit to a state of being lower than the impedance of the former replica circuit. With this configuration, the adjust errors generated in the replica circuits are canceled.

Abstract: A semiconductor device includes a fuse element, a read-out circuit that reads out a memory content of the fuse element in response to a first internal reset signal that is activated in response to transition of an external reset signal, and a latch circuit that holds therein the memory content read out by the read-out circuit and is reset by a second internal reset signal that is activated based on an activation period of the external reset signal. With this configuration, even when the activation period of the external reset signal is long, the time for which a current flows through the fuse element can be shortened, thereby making it possible to reduce a current consumption at the time of a reset operation.

Abstract: A semiconductor device includes a fuse element, a read-out circuit that reads out a memory content of the fuse element in response to a first internal reset signal that is activated in response to transition of an external reset signal, and a latch circuit that holds therein the memory content read out by the read-out circuit and is reset by a second internal reset signal that is activated based on an activation period of the external reset signal. With this configuration, even when the activation period of the external reset signal is long, the time for which a current flows through the fuse element can be shortened, thereby making it possible to reduce a current consumption at the time of a reset operation.

Abstract: To decrease the circuit scale necessary for the calibration of the output circuit and to decrease the time required for the calibration operation. The invention includes a first output buffer and a second output buffer that are connected to a data pin, and a calibration circuit that is connected to a calibration pin. The first output buffer and the second output buffer include plural unit buffers. The unit buffers have mutually the same circuit structures. With this arrangement, the impedances of the first output buffer and the second output buffer can be set in common, based on the calibration operation using the calibration circuit. Consequently, both the circuit scale necessary for the calibration operation and the time required for the calibration operation can be decreased.

Abstract: To include a first memory cell array area and a second memory cell array area, a peripheral circuit area arranged between these memory cell array areas, a first pad row arranged between the first memory cell array area and the peripheral circuit area, and a second pad row arranged between the second memory cell array area and the peripheral circuit area. No peripheral circuit is arranged substantially between the first memory cell array area and the first pad row as well as between the second memory cell array area and the second pad row. With this arrangement, a memory cell array area and a predetermined pad can be connected within a shorter distance by using a wiring formed in an upper layer that has a lower electrical resistance, and a power potential can be stably supplied to the memory cell array area.

Abstract: To provide a semiconductor device including a skew detecting circuit activated in a write leveling mode, and an ODT control circuit that activates a terminating resistance circuit connected to a data strobe terminal by using an ODT signal. The ODT control circuit selects a first resistance mode when a dynamic ODT is in an unused state in the write leveling mode, and selects a second resistance mode when the dynamic ODT is in a used state in the write leveling mode. With this configuration, a resistance in a used state of the dynamic ODT and that in an unused state of the dynamic ODT can be reproduced in an actual write operation. Consequently, a more accurate write leveling operation can be performed.

Abstract: To provide a semiconductor device including a skew detecting circuit activated in a write leveling mode, and an ODT control circuit that activates a terminating resistance circuit connected to a data strobe terminal by using an ODT signal. The ODT control circuit includes counters that delay the ODT signal, activates the terminating resistance circuit by using the ODT signal having passed the counters in a normal operation mode, and activates the terminating resistance circuit by using the ODT signal having bypassed the counters in the write leveling mode. With this configuration, in the write leveling mode, a write leveling operation can be performed quickly without waiting for latency of the ODT signal.