Abstract: A memory cell power supply circuit for each column includes a first PMOS transistor and a second PMOS transistor connected together in series between a first power supply and a second power supply. A connection point between the first and second PMOS transistors is output as a memory cell power supply. A control signal which is based on a column select signal and a write control signal is input to a gate terminal of the first PMOS transistor. A signal which is an inverted version of the signal input to the gate terminal of the first PMOS transistor is input to a gate terminal of the second PMOS transistor.

Abstract: A semiconductor integrated circuit includes a P-type MOS transistor and two or more N-type MOS transistors connected together in series between a first and a second power supply, an input terminal connected to a gate terminal of the P-type MOS transistor and gate terminals of the two or more N-type MOS transistors, an output terminal which is a connection node between the P-type MOS transistor and one of the two or more N-type MOS transistors connected to the P-type MOS transistor, and one or more capacitors connected to the output terminal. The drive capability of the P-type MOS transistor is higher than the overall drive capability of the two or more N-type MOS transistors connected together in series. Therefore, a semiconductor integrated circuit is provided in which fluctuations in the delay time of a delay circuit caused by variations in transistor characteristics can be reduced.

Abstract: A system LSI (100) having a logic circuit (104) and a plurality of SRAM macros (103) includes a power supply circuit (102) configured to receive a voltage (VDDP) supplied from the outside of the system LSI (100), and to generate a stabilized voltage (VDDM) lower than the voltage (VDDP). An SRAM memory cell (103a) of each of the plurality of SRAM macros (103) is supplied with the voltage (VDDM) generated by the power supply circuit (102), and an SRAM logic circuit (103b) of each of the plurality of SRAM macros (103) is supplied with a voltage (VDD) supplied from the outside. In addition, the logic circuit (104) is supplied with the voltage (VDD) from the outside.

Abstract: A semiconductor memory device includes a first inverter and a second inverter each having an input and an output, the output of each of the first and second inverters being connected to the input of the other so that data is stored, a CMOS switch configured to connect the input of the first inverter and a write bit line, a read MOS transistor having a gate connected to the output of the first inverter, and a MOS switch configured to connect the read MOS transistor to a read bit line. The first and second inverters have different sizes and are connected to different source power supplies.

Abstract: A semiconductor integrated circuit includes a P-type MOS transistor and two or more N-type MOS transistors connected together in series between a first and a second power supply, an input terminal connected to a gate terminal of the P-type MOS transistor and gate terminals of the two or more N-type MOS transistors, an output terminal which is a connection node between the P-type MOS transistor and one of the two or more N-type MOS transistors connected to the P-type MOS transistor, and one or more capacitors connected to the output terminal. The drive capability of the P-type MOS transistor is higher than the overall drive capability of the two or more N-type MOS transistors connected together in series. Therefore, a semiconductor integrated circuit is provided in which fluctuations in the delay time of a delay circuit caused by variations in transistor characteristics can be reduced.

Abstract: A semiconductor memory device comprises a plurality of memory cells each including a holding circuit for holding memory data, and a read-only output circuit for outputting a signal corresponding to the data held by the holding circuit. The read-only output circuit has a read drive transistor controlled in accordance with a signal held by the holding circuit. A gate length of the read drive transistor is longer than a gate length of a transistor included in the holding circuit. Alternatively, the read-only output circuit has a read access transistor controlled in accordance with a read word select signal, and a gate length of the read access transistor is longer than a gate length of a transistor included in the holding circuit.

Abstract: A semiconductor memory device includes a memory cell provided at an intersection of a word line and a bit line, a precharge circuit connected to the bit line, a column select circuit controlled in accordance with a write control signal, and a clamp circuit provided as a write circuit. The clamp circuit includes a transistor configured to control the potential of a selected bit line to a first potential (e.g., 0 V), and a variable capacitor configured to control the potential of the selected bit line to a second potential (e.g., a negative potential) which is lower than the first potential. The capacitance of the variable capacitor decreases when a power supply voltage is increased, whereby the amount of a decrease from the first potential to the second potential is reduced.

Abstract: In a semiconductor memory including word lines and bit lines arranged in a matrix and a plurality of memory cells provided at intersections of the word lines and the bit lines, a bit line precharge circuit is provided for controlling the potential of a low-data holding power supply coupled to memory cells provided on a corresponding one of the bit lines. In a write operation, the bit line precharge circuit controls the potential of a low-data holding power supply of a memory cell corresponding to a selected bit line to be higher than the potential of a low-data holding power supply of a memory cell corresponding to an unselected bit line.

Abstract: A system LSI (100) having a logic circuit (104) and a plurality of SRAM macros (103) includes a power supply circuit (102) configured to receive a voltage (VDDP) supplied from the outside of the system LSI (100), and to generate a stabilized voltage (VDDM) lower than the voltage (VDDP). An SRAM memory cell (103a) of each of the plurality of SRAM macros (103) is supplied with the voltage (VDDM) generated by the power supply circuit (102), and an SRAM logic circuit (103b) of each of the plurality of SRAM macros (103) is supplied with a voltage (VDD) supplied from the outside. In addition, the logic circuit (104) is supplied with the voltage (VDD) from the outside.

Abstract: A semiconductor memory device comprises a plurality of memory cells each including a holding circuit for holding memory data, and a read-only output circuit for outputting a signal corresponding to the data held by the holding circuit. The read-only output circuit has a read drive transistor controlled in accordance with a signal held by the holding circuit. A gate length of the read drive transistor is longer than a gate length of a transistor included in the holding circuit. Alternatively, the read-only output circuit has a read access transistor controlled in accordance with a read word select signal, and a gate length of the read access transistor is longer than a gate length of a transistor included in the holding circuit.

Abstract: A semiconductor memory device comprises a plurality of memory cells each including a holding circuit for holding memory data, and a read-only output circuit for outputting a signal corresponding to the data held by the holding circuit. The read-only output circuit has a read drive transistor controlled in accordance with a signal held by the holding circuit. A gate length of the read drive transistor is longer than a gate length of a transistor included in the holding circuit. Alternatively, the read-only output circuit has a read access transistor controlled in accordance with a read word select signal, and a gate length of the read access transistor is longer than a gate length of a transistor included in the holding circuit.

Abstract: A semiconductor memory device includes a first inverter and a second inverter each having an input and an output, the output of each of the first and second inverters being connected to the input of the other so that data is stored, a CMOS switch configured to connect the input of the first inverter and a write bit line, a read MOS transistor having a gate connected to the output of the first inverter, and a MOS switch configured to connect the read MOS transistor to a read bit line. The first and second inverters have different sizes and are connected to different source power supplies.

Abstract: A semiconductor memory device includes a memory cell provided at an intersection of a word line and a bit line, a precharge circuit connected to the bit line, a column select circuit controlled in accordance with a write control signal, and a clamp circuit provided as a write circuit. The clamp circuit includes a transistor configured to control the potential of a selected bit line to a first potential (e.g., 0 V), and a variable capacitor configured to control the potential of the selected bit line to a second potential (e.g., a negative potential) which is lower than the first potential. The capacitance of the variable capacitor decreases when a power supply voltage is increased, whereby the amount of a decrease from the first potential to the second potential is reduced.

Abstract: A semiconductor memory device comprises a plurality of memory cells each including a holding circuit for holding memory data, and a read-only output circuit for outputting a signal corresponding to the data held by the holding circuit. The read-only output circuit has a read drive transistor controlled in accordance with a signal held by the holding circuit. A gate length of the read drive transistor is longer than a gate length of a transistor included in the holding circuit. Alternatively, the read-only output circuit has a read access transistor controlled in accordance with a read word select signal, and a gate length of the read access transistor is longer than a gate length of a transistor included in the holding circuit.

Abstract: A semiconductor memory device comprises a plurality of memory cells each including a holding circuit for holding memory data, and a read-only output circuit for outputting a signal corresponding to the data held by the holding circuit. The read-only output circuit has a read drive transistor controlled in accordance with a signal held by the holding circuit. A gate length of the read drive transistor is longer than a gate length of a transistor included in the holding circuit. Alternatively, the read-only output circuit has a read access transistor controlled in accordance with a read word select signal, and a gate length of the read access transistor is longer than a gate length of a transistor included in the holding circuit.

Abstract: A semiconductor memory device includes a memory cell having a circuit configuration in which a potential supplied to sources of load transistors 108 and 111 included in a latch section is different from at least one of a potential supplied to a word line 105 and a potential supplied to bit lines 106 and 107; a latch potential control circuit 101 for switching a normal operation mode and a test mode to each other in accordance with a signal applied to a test mode setting pin 102; and a read/write control circuit 103 for controlling the potential supplied to the sources of the load transistors 108 and 111 to be lower than at least one of the potential supplied to the word line 105 and the potential supplied to the bit lines 106 and 107, during an arbitrary period of at least a read operation in the test mode.

Abstract: A semiconductor memory device having a memory cell including a flip-flop; and a memory cell power supply circuit for supplying a low voltage cell power supply voltage to the memory cell. The memory cell power supply circuit supplies a cell power supply voltage in a first period and a different cell power supply voltage in a second period, a predetermined first power supply voltage in case where the cell power supply voltage in supplied in a data read cycle and in a case where data is not written to a memory cell to which the cell power supply voltage is supplied in a write cycle, and a second power supply voltage higher than the first power supply voltage in a case where data is written to a memory cell to which the cell power supply voltage is supplied in a write cycle.

Abstract: A semiconductor memory device includes a memory cell having a circuit configuration in which a potential supplied to sources of load transistors 108 and 111 included in a latch section is different from at least one of a potential supplied to a word line 105 and a potential supplied to bit lines 106 and 107; a latch potential control circuit 101 for switching a normal operation mode and a test mode to each other in accordance with a signal applied to a test mode setting pin 102; and a read/write control circuit 103 for controlling the potential supplied to the sources of the load transistors 108 and 111 to be lower than at least one of the potential supplied to the word line 105 and the potential supplied to the bit lines 106 and 107, during an arbitrary period of at least a read operation in the test mode.

Abstract: A semiconductor storage device has memory cells provided at intersections of word lines and bit lines, a precharge circuit connected to the bit lines, and a write circuit. The write circuit includes a column selection circuit controlled by a write control signal, a transistor for controlling a potential of a selected bit line so that the potential of the selected bit line is a first potential (e.g., 0 V), a capacitance element for controlling the potential of the selected bit line so that the potential of the selected bit line is a second potential (e.g., a negative potential) that is lower than the first potential, and a clamp circuit for clamping the second potential when a power supply voltage becomes high.

Abstract: A semiconductor integrated circuit includes: a memory cell array including a plurality of SRAM memory cells; a characteristic measuring circuit including a plurality of transistor circuits connected in parallel; and a first terminal. The plurality of transistor circuits each include a first transistor configured in the same manner as one of transistors included in one of the SRAM memory cells. The first transistor is connected so as to control current between the first terminal and a node at a reference potential according to a voltage supplied to a gate of the first transistor.