Abstract: A temperature sensing circuit activates a sensing signal when sensing that a temperature inside a semiconductor integrated circuit is lower than a predetermined temperature. A heat generation control circuit activates a heat generation control signal when the sensing signal is activated. When the heat generation control signal is activated, a current is generated inside a memory circuit to raise the temperature inside the semiconductor integrated circuit.

Abstract: A semiconductor memory device includes: a parity generating circuit for generating parity data corresponding to input data; a normal data latching section for latching the input data or data read out from the normal memory cell array; an input selection circuit for selectively outputting the input data or the parity data; a parity data latching section for latching and outputting the output from the input selection circuit or data read out from the parity memory cell array; and an error correction circuit for performing an error detection on the data latched by the normal data latching section by using the data latched by the parity data latching section, and performing an error correction if an error is detected, to output the obtained result. The parity data latching section outputs the data latched by itself externally of the semiconductor memory device.

Abstract: A temperature sensing circuit activates a sensing signal when sensing that a temperature inside a semiconductor integrated circuit is lower than a predetermined temperature. A heat generation control circuit activates a heat generation control signal when the sensing signal is activated. When the heat generation control signal is activated, a current is generated inside a memory circuit to raise the temperature inside the semiconductor integrated circuit.

Abstract: A semiconductor storage device including a memory cell and having a function of refreshing the memory cell, includes a clock generation circuit configured to receive a first clock, generate a second clock based on an inversion of the first clock, and output the second clock. The semiconductor storage device performs operation of the refresh function in synchronization with at least one of the first and second clocks.

Abstract: A semiconductor memory device of the present invention provides, in a memory having an hierarchical bit line structure, a test mode which causes all switches for selecting hierarchical bit lines and a main bit line in an activated memory array to be connected all the time. With this configuration, it is possible to perform a disturb refresh test on a memory cell arrays basis regardless of the hierarchical bit line structure. Possibility of an erroneous read-out, which may be caused by connecting each of the hierarchical bit lines to one another and a consequent increase in a bit line load capacity, may be prevented by providing a timing control such that the switches are connected after a normal mode operation.

Abstract: A semiconductor memory device includes: a parity generating circuit for generating parity data corresponding to input data; a normal data latching section for latching the input data or data read out from the normal memory cell array; an input selection circuit for selectively outputting the input data or the parity data; a parity data latching section for latching and outputting the output from the input selection circuit or data read out from the parity memory cell array; and an error correction circuit for performing an error detection on the data latched by the normal data latching section by using the data latched by the parity data latching section, and performing an error correction if an error is detected, to output the obtained result. The parity data latching section outputs the data latched by itself externally of the semiconductor memory device.

Abstract: In a semiconductor memory, a sub bit line hierarchical switch is provided correspondingly to each sub bit line between the sub bit line and a main bit line corresponding to the sub bit line, and a complementary sub bit line hierarchical switch is provided correspondingly to each complementary sub bit line between the complementary sub bit line and a complementary main bit line corresponding to the complementary sub bit line. Furthermore, the semiconductor memory includes a hierarchical switch control unit for turning off all the sub bit line hierarchical switch and the complementary sub bit line hierarchical switch when a given signal is input.

Abstract: Through setting an internal test mode, a refresh operation for a DRAM is carried out by externally inputted address signals, instead of internally generated address signals, while maintaining the same number of memory cell arrays to be activated as that of memory cell arrays which are concurrently activated in a refresh for memory cell arrays. This configuration needs no drastic addition of circuits and allows a reduction in disturb test time for a plurality of memory cell arrays.

Abstract: In a semiconductor memory, a sub bit line hierarchical switch is provided correspondingly to each sub bit line between the sub bit line and a main bit line corresponding to the sub bit line, and a complementary sub bit line hierarchical switch is provided correspondingly to each complementary sub bit line between the complementary sub bit line and a complementary main bit line corresponding to the complementary sub bit line. Furthermore, the semiconductor memory includes a hierarchical switch control unit for turning off all the sub bit line hierarchical switch and the complementary sub bit line hierarchical switch when a given signal is input.

Abstract: Through setting an internal test mode, a refresh operation for a DRAM is carried out by externally inputted address signals, instead of internally generated address signals, while maintaining the same number of memory cell arrays to be activated as that of memory cell arrays which are concurrently activated in a refresh for memory cell arrays. This configuration needs no drastic addition of circuits and allows a reduction in disturb test time for a plurality of memory cell arrays.

Abstract: A semiconductor memory device of the present invention provides, in a memory having an hierarchical bit line structure, a test mode which causes all switches for selecting hierarchical bit lines and a main bit line in an activated memory array to be connected all the time. With this configuration, it is possible to perform a disturb refresh test on a memory cell arrays basis regardless of the hierarchical bit line structure. Possibility of an erroneous read-out, which may be caused by connecting each of the hierarchical bit lines to one another and a consequent increase in a bit line load capacity, may be prevented by providing a timing control such that the switches are connected after a normal mode operation.

Abstract: Conventionally, when a burn-in test is performed by means of utilizing a memory BIST circuit, a control of a reset operation for the memory BIST circuit is required from an external source. According to the present invention, it is configured that the memory BIST circuit is used for the burn-in test of a memory macro, and a BIST reset control circuit detects a memory BIST test completion signal from the memory BIST circuit, and automatically resets the memory BIST circuit. Thereby, repetitive continuous tests to the memory macro by the memory BIST circuit can be achieved, and the burn-in test by means of utilizing the memory BIST circuit can be performed.

Abstract: In recent system LSIs, a plurality of RAMs differing in capacity and in bit width have come to be mounted on a single chip according to the needs on the system side. However, when testing the plurality of RAMs, if the RAMs differ in capacity, they cannot be tested using the same test pattern (for example, HALF-MARCH) even if a special pin is provided for each RAM, because X, Y address mapping differs between the different RAMs; accordingly, the test has to be performed by dividing the RAMs into groups each consisting of RAMs having the same memory space, and this has lead to increased test time. An external address signal and a test-only address signal are provided as RAM control signals and, in the latter case, the number of X, Y addresses in each of the RAMs 4 and 5 is set equal to that of the largest capacity RAM 3 within the same chip, thereby making the X, Y address mapping the same for all the RAMs 3 to 5.

Abstract: Conventionally, when a burn-in test is performed by means of utilizing a memory BIST circuit, a control of a reset operation for the memory BIST circuit is required from an external source. According to the present invention, it is configured that the memory BIST circuit is used for the burn-in test of a memory macro, and a BIST reset control circuit detects a memory BIST test completion signal from the memory BIST circuit, and automatically resets the memory BIST circuit. Thereby, repetitive continuous tests to the memory macro by the memory BIST circuit can be achieved, and the burn-in test by means of utilizing the memory BIST circuit can be performed.

Abstract: A semiconductor memory device has a plurality of memory cells each having a first transistor, a second transistor having a source or drain connected to one portion of the source or drain of the first transistor, and a third transistor having a source or drain connected to the other portion of the source or drain of the first transistor. The first transistor accumulates, in the channel thereof, charges transferred from the second and third transistors.

Abstract: Strap lines are provided in a layer above word lines so that the word lines and the strap lines are connected to each other in strapping regions separately provided at the ends of memory cell array portions in a conventional semiconductor memory device having a problem wherein the area of the memory cell array portions is increased. Each memory cell is formed of a MOS transistor and a MOS capacitor in a layout of a memory cell array portion according to a standard CMOS process. Memory cells of this structure have a sufficiently large pitch between bit lines and, therefore, contacts for connecting word lines to strap lines in an upper layer are provided between the bit lines, as low resistance metal wires, in the same layer as the bit lines.

Abstract: In recent system LSIs, a plurality of RAMs differing in capacity and in bit width have come to be mounted on a single chip according to the needs on the system side. However, when testing the plurality of RAMs, if the RAMs differ in capacity, they cannot be tested using the same test pattern (for example, HALF-MARCH) even if a special pin is provided for each RAM, because X, Y address mapping differs between the different RAMs; accordingly, the test has to be performed by dividing the RAMs into groups each consisting of RAMs having the same memory space, and this has lead to increased test time. An external address signal and a test-only address signal are provided as RAM control signals and, in the latter case, the number of X, Y addresses in each of the RAMs 4 and 5 is set equal to that of the largest capacity RAM 3 within the same chip, thereby making the X, Y address mapping the same for all the RAMs 3 to 5.

Abstract: A folded bitline type sense amplifier circuit is disposed at an outer side of an end memory cell array in which 2Tr1C type cells each composed of a data storage capacitor, an A port access transistor and a B port access transistor are arranged in the form of a matrix, and two word lines used for cell selection are connected to corresponding gates of the A and B port access transistors. The drain of the A port access transistor is connected to one bit line of an open bitline type sense amplifier circuit, and the drain of the B port access transistor is connected to one bit line out of a bit line pair of the folded bitline sense amplifier circuit.

Abstract: A semiconductor memory device has a plurality of memory cells each having a first transistor, a second transistor having a source or drain connected to one portion of the source or drain of the first transistor, and a third transistor having a source or drain connected to the other portion of the source or drain of the first transistor. The first transistor accumulates, in the channel thereof, charges transferred from the second and third transistors.

Abstract: A folded bitline type sense amplifier circuit is disposed at an outer side of an end memory cell array in which 2Tr1C type cells each composed of a data storage capacitor, an A port access transistor and a B port access transistor are arranged in the form of a matrix, and two word lines used for cell selection are connected to corresponding gates of the A and B port access transistors. The drain of the A port access transistor is connected to one bit line of an open bitline type sense amplifier circuit, and the drain of the B port access transistor is connected to one bit line out of a bit line pair of the folded bitline sense amplifier circuit.