Abstract: A semiconductor memory with a memory core for dynamically holding data in which a data collision at the time of the semiconductor memory making the transition from a standby state to a nonstandby state is prevented. A first buffer circuit inputs an enable signal for controlling a standby state or a nonstandby state. A second buffer circuit outputs a predetermined logic signal or a read/write signal for controlling the reading of data from or the writing of data to the memory core in accordance with the enable signal. A third buffer circuit outputs an inverted signal obtained by inverting the logic signal or the read/write signal in accordance with the enable signal. A control circuit controls the reading or writing of the data by the read/write signal outputted from the second buffer circuit. A data output control circuit controls the inputting of the data from or the outputting of the data to the outside by the inverted signal or the read/write signal outputted from the third buffer circuit.

Abstract: A timer measures a predetermined time from the reception of an external access signal, and outputs an access request signal after the predetermined time has elapsed. The external access signal causes a memory core to execute a read operation, and the access request signal causes the memory core to operate. The predetermined time is set to be longer than a core operation time for the memory core to perform a single operation. The memory core thus performs no operation when the external access signal varies in a time shorter than the predetermined time. Consequently, it is possible to prevent the memory core from malfunctioning and data retained therein from crashing even when external access signals are supplied at intervals at which the memory core is unable to properly operate.

Abstract: Second memory cells of a second memory block each have an area 2a times (a is a positive integer) that of each first memory cell of a first memory block. Sizing the first and second memory cells in a predetermined ratio can make easily identical the dimensions of the first memory block and the second memory block. Consequently, it is possible to easily align peripheral circuits to lie around the plurality of first and second memory blocks, such as decoders. This also facilitates the wiring of signal lines to be connected to the peripheral circuits. This makes it possible to improve the layout design efficiency for a semiconductor integrated circuit. Thus, a plurality of types of memory blocks can be formed on a semiconductor integrated circuit efficiently. The semiconductor integrated circuit can be prevented from increasing in chip size depending on the layout design, owing to its simplified layout.

Abstract: A semiconductor memory device includes a first bit line connected to a memory cell via a transistor, a transfer gate, a second bit line connected to the first bit line via the transfer gate, a sense amplifier connected to the second bit line, a first precharge circuit for precharging the first bit line, a second precharge circuit for precharging the second bit line, a control circuit which precharges the first bit line by the first precharge circuit after closing the transfer gate, followed by subsequent precharging of the second bit line by the second precharge circuit.

Abstract: A semiconductor integrated circuit device comprises a plurality of MIS transistors, and an integrated circuit unit including logic gate circuits configured by a combination of the plurality of MIS transistors. Each of the MIS transistors has a gate including a circuit element represented by an equivalent circuit in which a capacitance and resistance are parallel-connected.

Abstract: A semiconductor integrated circuit includes a switch unit for controlling the supply of a power source voltage to a signal amplification circuit for receiving an input signal, and a control unit for selectively turning ON and OFF the switch unit in accordance with the amplitude or frequency of the input signal. By the constitution, it is possible to provide an input circuit or an output circuit capable of being applied to an input/output interface adapted for a small amplitude operation.

Abstract: A semiconductor integrated circuit includes a switch unit for controlling the supply of a power source voltage to a signal amplification circuit for receiving an input signal, and a control unit for selectively turning ON and OFF the switch unit in accordance with the amplitude or frequency of the input signal. By the constitution, it is possible to provide an input circuit or an output circuit capable of being applied to an input/output interface adapted for a small amplitude operation.

Abstract: A semiconductor memory with a memory core for dynamically holding data in which a data collision at the time of the semiconductor memory making the transition from a standby state to a nonstandby state is prevented. A first buffer circuit inputs an enable signal for controlling a standby state or a nonstandby state. A second buffer circuit outputs a predetermined logic signal or a read/write signal for controlling the reading of data from or the writing of data to the memory core in accordance with the enable signal. A third buffer circuit outputs an inverted signal obtained by inverting the logic signal or the read/write signal in accordance with the enable signal. A control circuit controls the reading or writing of the data by the read/write signal outputted from the second buffer circuit. A data output control circuit controls the inputting of the data from or the outputting of the data to the outside by the inverted signal or the read/write signal outputted from the third buffer circuit.

Abstract: A twin-cell type semiconductor memory device in which the area of a chip can be reduced. In the twin-cell type semiconductor memory device for storing data in at least one pair of memory cells as complementary information, memory cells are arranged at each of a plurality of word lines at intervals at which bit lines are located. At least the one pair of memory cells, which have stored the complementary information and which indicate a plurality of areas each connected to a pair of bit lines, form a twin cell.

Abstract: A semiconductor integrated circuit includes a switch unit for controlling the supply of a power source voltage to a signal amplification circuit for receiving an input signal, and a control unit for selectively turning ON and OFF the switch unit in accordance with the amplitude or frequency of the input signal. By the constitution, it is possible to provide an input circuit or an output circuit capable of being applied to an input/output interface adapted for a small amplitude operation.

Abstract: A semiconductor device includes a word line drive circuit for resetting the word line by driving the word line connected to a memory cell and is constituted so as to switch a reset level of the word line drive circuit, which is set at the time of the reset operation of the word line, between a first potential such as a ground potential and a second potential such as a negative potential. Further, a semiconductor device including a memory cell array formed by arranging a plurality of memory cells and a word line reset level generating circuit for generating a negative potential makes it possible to vary the amount of a current supply of the word line reset level generating circuit when non-selected word lines are set to a negative potential by applying the output of the word line reset level generating circuit to the non-selected word lines, and varies the amount of the current supply of the negative potential in accordance with the operation of the memory cell array.

Abstract: A semiconductor device includes input circuits which capture respective data pieces from an exterior of the device in synchronization with respective clock signals supplied from the exterior of the device, a pulse signal generation circuit which generates a pulse signal, and drive circuits which supplies the respective data pieces captured by the input circuits to internal circuitry at a unified timing corresponding to the pulse signal.

Abstract: A delay circuit includes a delay part delaying a signal by a delay time which can be varied based on a control current, and a control current adjustment circuit adjusting the control current so that the delay time changes linearly based on a variation in a resistance value.

Abstract: The present invention is a memory circuit which selects N number of segments out of M number of segments (N<M) during normal reading, wherein all the M number of segments are activated during a read test in order to drive a common data bus for testing by a plurality of sense buffers in the M number of segments. For this, test signals are supplied to a column decoder, and segment select signals, for activating the M number of segments, are generated in response to the test signal. In this way, a plurality of segments in a memory bank in a select status can be simultaneously selected to execute a read test, and the efficiency of a compression read test can be improved.

Abstract: A delay circuit and a plurality of accepting circuits are comprised. The input signal supplied from exterior is delayed for a predetermined length of time by the delay circuit, and then it is distributed and output to the plurality of the receiver circuits. The delay time of the delay circuit is adjusted to optimize an accepting timing to an input signal by a clock signal in each of the accepting circuit. The each accepting circuit reliably accepts the delayed input signal respectively in synchronization with a clock signal. Therefore, it is unnecessary to respectively provide a delay circuit in the plurality of the accepting circuits. As a result, the plurality of accepting circuits can reliably accept input signals without enlarging a circuit scale. A plurality of delay circuits, a plurality of accepting circuits, and an operating circuit are comprised. The delay circuit receives a plurality of input signals, and outputs each of the delayed input signals respectively to the plurality of accepting circuits.

Abstract: A semiconductor device includes a word line drive circuit resetting the word line by driving the word line connected to a memory cell and switching a reset level of the word line drive circuit at the time of the reset operation of the word line. Further, a semiconductor device includes a memory cell array formed by arranging a plurality of memory cells and a reset level switch circuit for selecting a first potential or a second potential and supplying the first potential or the second potential to the word line drive circuit.

Abstract: A delay circuit and a plurality of accepting circuits are comprised. The input signal supplied from exterior is delayed for a predetermined length of time by the delay circuit, and then it is distributed and output to the plurality of the receiver circuits. The delay time of the delay circuit is adjusted to optimize an accepting timing to an input signal by a clock signal in each of the accepting circuit. The each accepting circuit reliably accepts the delayed input signal respectively in synchronization with a clock signal. Therefore, it is unnecessary to respectively provide a delay circuit in the plurality of the accepting circuits. As a result, the plurality of accepting circuits can reliably accept input signals without enlarging a circuit scale. A plurality of delay circuits, a plurality of accepting circuits, and an operating circuit are comprised. The delay circuit receives a plurality of input signals, and outputs each of the delayed input signals respectively to the plurality of accepting circuits.

Abstract: A semiconductor integrated circuit, comprising a circuit unit having a predetermined function such as a level shifter circuit or a driver transistor circuit by a combination of a plurality of transistors, is disclosed. Among a plurality of the transistors of the circuit unit, the source potential of at least one transistor adapted to turn off during the standby period of the circuit unit is changed. Preferably, the semiconductor integrated circuit is configured to reduce the sub-threshold current flowing between the source and the drain of at least one transistor adapted to turn off during the standby period of the circuit unit by changing the source potential at a timing based on the standby period of the circuit unit in such a manner that a predetermined bias voltage is applied between the gate and the source of the transistor. A method of switching the source potential of at least one transistor in the semiconductor integrated circuit having the configuration described above is also disclosed.

Abstract: A semiconductor memory device includes a first bit line connected to a memory cell via a transistor, a transfer gate, a second bit line connected to the first bit line via the transfer gate, a sense amplifier connected to the second bit line, a first precharge circuit for precharging the first bit line, a second precharge circuit for precharging the second bit line, a control circuit which precharges the first bit line by the first precharge circuit after closing the transfer gate, followed by subsequent precharging of the second bit line by the second precharge circuit.

Abstract: A clock synchronizing method is provided. The clock synchronizing method includes the step of detecting a phase difference of a synchronous clock from a reference clock, and the step of varying a phase of the synchronous clock in one direction when the phase difference is not within a predetermined range, and varying the phase of the synchronous clock in one of the one direction and the other direction according to the phase difference when the phase difference is within the predetermined range.