Abstract: The invention relates to a clock synchronous type semiconductor device that accepts an input signal inputted from the exterior in synchronization with a clock signal. The semiconductor device according to the invention includes an input signal receiving unit that receives an input signal inputted from the exterior, where the receiving is done in synchronization with a clock signal; a clock timing selecting unit for outputting a clock selecting signal; and a clock generating unit that, in response to receiving a clock selecting signal and an external clock signal, generates a clock signal at a predetermined timing which corresponds to a signal level of the clock selecting signal, and outputs the clock signal to the input signal receiving unit, wherein it is possible to securely accept an input signal regardless of the frequency of the external clock signal.

Abstract: A semiconductor memory device includes bit lines which transfer data of memory cells, a plurality of first sense amplifier circuits connected to odd-number lines of the bit lines, a plurality of second sense amplifier circuits connected to even-number lines of the bit lines, and a clamp-voltage generation circuit which supplies a first clamp voltage to the first sense amplifier circuits, and supplies a second clamp voltage to the second sense amplifier circuits, whereby during test operation, the odd-number lines are clamped to the first clamp voltage, and the even-number lines are clamped to the second clamp voltage.

Abstract: A semiconductor memory device includes isolation circuits disconnecting cell arrays from sense amplifiers, and isolation signal generating circuits generating isolation signals that control the isolation circuits. The isolation signal generating circuits are hierarchically divided into main isolation signal generating circuits and sub isolation signal generating circuits. The sub isolation signal generating circuits generate sub isolation signals having a first potential on a high-potential side. The main isolation signal generating circuits generate main isolation signals having a second potential on the high-potential side, the second potential being lower than the first potential.

Abstract: A semiconductor memory device having a self-refresh operation includes a first circuit generating a first signal that specifies a first self-refresh cycle by a non-volatile circuit element provided in the semiconductor memory device, a second circuit receiving a second signal that specifies a second self-refresh cycle via a terminal that is used in common to another signal, and a third circuit generating a pulse signal having one of the first and second self-refresh cycles, the pulse signal being related to the self-refresh operation.

Abstract: A semiconductor memory device having a self-refresh operation includes a detection circuit generating a detection signal when detecting a change of a given input signal, and a comparator circuit comparing the detection signal with a refresh request signal internally generated and generating a control signal indicative of a circuit operation.

Abstract: A high-speed DRAM, which comprises a plurality of separated operation circuits that perform accessing the memory cell array according to the detection of the transition of input signals and prevents a fatal malfunction even when glitches are generated in input signals, has been disclosed. The DRAM is designed so that erroneous data is not written to or read from by varying the possibility (sensitivity) with which a plurality of separated operation circuits initiate the operation according to the ATD signal.

Abstract: Memory cell blocks respectively have a plurality of memory cell rows and a redundancy memory cell row for relieving a defect in these memory cell rows, memory cells being arranged in the memory cell rows. A first decoder selects any of the memory cell blocks. A second decoder selects any of the memory cell rows in the memory cell block. The operation of the second decoder not in use for decoding in the redundancy memory cell row is suspended when the redundancy memory cell row operates. The absence of unnecessary circuit operation allows a reduction in power consumption when the redundancy memory cell row operates. Even in a semiconductor integrated circuit having a plurality of memory banks each including the plurality of memory cell blocks, the first decoder, and the second decoder, it is possible to reduce power consumption when the redundancy memory cell rows operates.

Abstract: A semiconductor device which has a test mode for testing the semiconductor device, is provided with a circuit which generates a first signal based on dummy command signals which are input thereto a plurality of times, and generates a second signal which instructs entry to a corresponding test mode or an exit from a corresponding test mode based on an address signal and the first signal.

Abstract: The present invention provides a semiconductor memory device of a twin-storage type having an operation control method and a circuit structure that achieve a higher process rate, a less power consumption, and a smaller chip area. This semiconductor memory device includes bit lines in pairs, a sense amplifier connected to each pair of the bit lines, a first memory cell connected to one bit line of each pair of the bit lines, a second memory cell that is connected to the other bit line of each pair of the bit lines and stores the inverted data of the data stored in the first memory cell. This semiconductor memory device is characterized by not having means to pre-charge the bit lines to a predetermined potential. The semiconductor memory device of the present invention is also characterized by including a control circuit that controls the sense amplifier to start a pull-down operation after starting a pull-up operation.

Abstract: A semiconductor storage device conducts a late-write operation. The semiconductor storage device comprises: a memory core circuit storing data; a data latch circuit storing preceding data corresponding to a preceding write-operation; an address compare circuit comparing a preceding address corresponding to the preceding write-operation and a present address corresponding to a present read-operation so as to determine whether the preceding address and the present address match each other; and a control circuit. The control circuit controls a test read-operation to read data from the memory core circuit regardless of whether the preceding address and the present address match each other.

Abstract: The present invention is a memory circuit having a plurality of word lines, a plurality of bit line pairs, and memory cells disposed at the cross-position thereof. The memory comprises: a sense amplifier which is shared by the first bit line pair and the second bit line pair disposed in the column direction and amplifies a voltage of the bit line pairs; a first and a second bit line transfer gates which are disposed between the sense amplifier and the first and second bit line pairs, and connects the bit line pair at the selected memory cell side to the sense amplifier; a bit line clamper, which is disposed between the first and second bit line transfer gates, is shared by the first bit line pair and the second bit line pair, and supplies the precharge level to the bit line pairs; and a bit line short circuit, which is disposed at the first and the second bit line pairs respectively and shorts the bit line pairs.

Abstract: A semiconductor memory device having memory cells, spare memory cells to replace defective memory cells and a decision block. The decision block has a plurality of groups, each of which decides whether an input address is an address which selects a memory cell in the defective memory cells. A signal having a different address expression type of the input address is provided to each of the groups.

Abstract: The present invention is aimed at providing a semiconductor memory device which performs a row-address pipe-line operation in accessing different row addresses so as to achieve high-speed access. The semiconductor memory device according to the present invention includes a plurality of sense-amplifiers which store data when the data is received via bit lines from memory cells corresponding to a selected word line, a column decoder which reads parallel data of a plurality of bits from selected sense amplifiers by simultaneously selecting a plurality of column gates in response to a column address, a data-conversion unit which converts the parallel data into serial data, and a precharge-signal-generation unit which generates an internal precharge signal a first delay-time period after generation of a row-access signal for selecting the selected word line so as to reset the bit lines and said plurality of sense-amplifiers.

Abstract: One aspect of the present invention is characterized in that an input buffer circuit constitutes either 2 sets, or a plurality of sets relative to 1 input signal, either a pair of complementary internal clocks, or a plurality of internal clocks are generated by frequency-dividing a supplied clock inside the integrated circuit device, and input signals are received and latched either in synchronization with a pair of complementary clocks, or in synchronization with a plurality of clocks in accordance with an input buffer of either 2 sets or a plurality of sets. The output of input buffers of either 2 sets or a plurality of sets are combined by a combining circuit, and supplied internally. An H level or an L level period is set for the internally-generated internal clock so that outputs from the various input buffers are not in contention with one another.

Abstract: A semiconductor memory device using hierarchical word decoding for word selection includes memory-cell areas, each of which is provided for a corresponding one of column blocks. The semiconductor memory device further includes sub-word lines provided for each one of the column blocks and extending over a corresponding one of the memory-cell areas, and sub-word decoders provided on either side of a given one of the memory-cell areas to select one of the sub-word lines only with respect to the given one of the memory-cell areas.

Abstract: A semiconductor memory includes memory cell blocks, a burst-length information generating circuit which generates burst-length information based on a burst length, and a block enable circuit which receives the burst-length information. The block enable circuit selectively enables one of the memory cell blocks when the burst length is equal to or shorter than a predetermined burst length and selectively enables a plurality of memory cell blocks based on the burst length when the burst length is longer than the predetermined burst length. Data are read from the above-mentioned one or plurality of memory cell blocks.

Abstract: The present invention is an FCRAM comprising a first stage for performing command decoding, a second stage for performing sense amplifier activation, and a third stage for performing data input and output, configured in a pipeline structure, a plurality of data bits being transferred in parallel between the sense amplifiers and the third stage, wherein sense amplifiers are deactivated automatically and a reset operation is performed after data has been transferred in parallel between sense amplifiers and the third stage, in response to a standard read or write command.

Abstract: A semiconductor integrated circuit configured of a DRAM or the like has a function of generating a step-up voltage and supplying it to a plurality of semiconductor devices. During the period when a burn-in test is conducted, the input voltage of a precharge portion for precharging a step-up node for outputting the step-up voltage is clamped to a predetermined level by a precharge input voltage clamping unit. The precharge input voltage clamping unit prevents the step-up voltage level across the step-up node from excessively increasing during the burn-in test.

Abstract: The present invention is aimed at providing a semiconductor memory device which performs a row-address pipe-line operation in accessing different row addresses so as to achieve high-speed access. The semiconductor memory device according to the present invention includes a plurality of sense-amplifiers which store data when the data is received via bit lines from memory cells corresponding to a selected word line, a column decoder which reads parallel data of a plurality of bits from selected sense amplifiers by simultaneously selecting a plurality of column gates in response to a column address, a data-conversion unit which converts the parallel data into serial data, and a precharge-signal-generation unit which generates an internal precharge signal a first delay-time period after generation of a row-access signal for selecting the selected word line so as to reset the bit lines and said plurality of sense-amplifiers.

Abstract: There is provided a semiconductor integrated circuit memory comprising banks each having at least one memory cell array and connected to a first data bus. Each of the banks includes a control part which is supplied with information indicated by a command and thus controls a data write or read operation on a corresponding bank. The control part controls data write and read operations on the corresponding bank so that the corresponding bank is prevented from occupying the first data bus until read data is output to the first data bus by the data read operation.