Patents by Inventor Masahisa Iida
Masahisa Iida has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 8151173Abstract: Data latches, multiplexers, an ECC circuit section, and an input/output circuit section are arranged in columns and adjacent to each other, in an extending direction of data lines that are formed in a direction orthogonal to word lines. A layout of a data path system is formed in bit slices. Further, parity bits are equally distributed so as to cause delay times of bits to be uniform.Type: GrantFiled: August 18, 2008Date of Patent: April 3, 2012Assignee: Panasonic CorporationInventors: Masanobu Hirose, Masahisa Iida
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Patent number: 8078949Abstract: 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.Type: GrantFiled: September 18, 2008Date of Patent: December 13, 2011Assignee: Panasonic CorporationInventors: Hiroyuki Sadakata, Masahisa Iida
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Patent number: 8065589Abstract: A semiconductor memory device includes a memory cell array from which all bits of a data signal having a first number of the bits composed of a main data signal and an error detection/correction code data signal are simultaneously read, a sense amplifier for amplifying the read data signal, a selection unit for selecting a data signal having a second number of bits forming a part of the data signal amplified by the sense amplifier, and an error detection/correction unit for performing error detection and correction based on at least a part of the selected data signal having the second number of bits, wherein the selection by the selection unit is performed based on a row address.Type: GrantFiled: September 10, 2008Date of Patent: November 22, 2011Assignee: Panasonic CorporationInventor: Masahisa Iida
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Publication number: 20110205829Abstract: In order to latch and store a word line reset level voltage (negative voltage) which is set during reset operation, a word line driver includes PMOS transistors and NMOS transistors. The word line driver further includes a stress-reducing PMOS transistor and an NMOS transistor, and also a word line bias control circuit which controls and activates a supply bias during setting of a word line, start of resetting, and a reset period.Type: ApplicationFiled: May 4, 2011Publication date: August 25, 2011Applicant: PANASONIC CORPORATIONInventor: Masahisa IIDA
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Publication number: 20110099459Abstract: A semiconductor memory device includes a memory array, an error correction code circuit, and a timing control signal generator configured to, based on a first timing control signal used to control a timing at which data to be input to the error correction code circuit is transferred to the error correction code circuit, generate a second timing control signal used to control a timing at which data output from the error correction code circuit is transferred to another circuit. The timing control signal generator includes a circuit which is the same as or corresponds to at least a portion of the error correction code circuit, and is configured to delay a timing of the first timing control signal by a period of time corresponding to a delay time of the error correction code circuit, and output the second timing control signal, depending on the delayed timing.Type: ApplicationFiled: December 28, 2010Publication date: April 28, 2011Applicant: PANASONIC CORPORATIONInventors: Toshihiro NAKAMURA, Masahisa IIda
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Patent number: 7738281Abstract: A semiconductor storage device according to the present invention comprises a plurality of memory cells each provided with an access transistor in which a source is connected to a bit line and a gate is connected to a word line and a capacitor in which a storage electrode is connected to a drain of the access transistor, the plurality of memory cells being placed in a matrix shape in column and row directions, a sense amplifier circuit connected to the source of the access transistor via the bit line, a bit-line precharge voltage generating circuit for generating a bit-line precharge voltage lower than a sense amplifier supply voltage to be supplied to the sense amplifier circuit and supplying the generated bit-line precharge voltage to the bit line, and a cell plate voltage generating circuit for generating a cell plate voltage set to be lower than the bit-line precharge voltage and supplying the generated cell plate voltage to a plate electrode of the capacitor.Type: GrantFiled: October 17, 2007Date of Patent: June 15, 2010Assignee: Panasonic CorporationInventor: Masahisa Iida
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Patent number: 7692993Abstract: A semiconductor memory device includes a plurality of memory blocks, a plurality of refresh block counters, a refresh word line counter, and an arbitration circuit. The plurality of refresh block counters generate block addresses of at least two memory blocks to select at least two memory blocks to be refreshed from the plurality of memory blocks. The refresh word line counter generates a common word line address that is common to the at least two memory blocks. The arbitration circuit generates at least one first word line address based on the at least two block addresses and the common word line address and arbitrate so that each word line indicated by the at least one first word line address is refreshed during a period in which a word line indicated by an externally applied second word line address is accessed.Type: GrantFiled: April 9, 2008Date of Patent: April 6, 2010Assignee: Panasonic CorporationInventors: Masahisa Iida, Kiyoto Ohta
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Publication number: 20090094493Abstract: A semiconductor memory device includes a memory cell array from which all bits of a data signal having a first number of the bits composed of a main data signal and an error detection/correction code data signal are simultaneously read, a sense amplifier for amplifying the read data signal, a selection unit for selecting a data signal having a second number of bits forming a part of the data signal amplified by the sense amplifier, and an error detection/correction unit for performing error detection and correction based on at least a part of the selected data signal having the second number of bits, wherein the selection by the selection unit is performed based on a row address.Type: ApplicationFiled: September 10, 2008Publication date: April 9, 2009Inventor: Masahisa Iida
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Publication number: 20090094504Abstract: 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.Type: ApplicationFiled: September 18, 2008Publication date: April 9, 2009Inventors: Hiroyuki Sadakata, Masahisa Iida
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Publication number: 20090089646Abstract: Data latches, multiplexers, an ECC circuit section, and an input/output circuit section are arranged in columns and adjacent to each other, in an extending direction of data lines that are formed in a direction orthogonal to word lines. A layout of a data path system is formed in bit slices. Further, parity bits are equally distributed so as to cause delay times of bits to be uniform.Type: ApplicationFiled: August 18, 2008Publication date: April 2, 2009Inventors: Masanobu Hirose, Masahisa Iida
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Publication number: 20080253212Abstract: A semiconductor memory device includes a plurality of memory blocks, a plurality of refresh block counters, a refresh word line counter, and an arbitration circuit. The plurality of refresh block counters generate block addresses of at least two memory blocks to select at least two memory blocks to be refreshed from the plurality of memory blocks. The refresh word line counter generates a common word line address that is common to the at least two memory blocks. The arbitration circuit generates at least one first word line address based on the at least two block addresses and the common word line address and arbitrate so that each word line indicated by the at least one first word line address is refreshed during a period in which a word line indicated by an externally applied second word line address is accessed.Type: ApplicationFiled: April 9, 2008Publication date: October 16, 2008Inventors: Masahisa IIDA, Kiyoto OHTA
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Publication number: 20080094921Abstract: A semiconductor storage device according to the present invention comprises a plurality of memory cells each provided with an access transistor in which a source is connected to a bit line and a gate is connected to a word line and a capacitor in which a storage electrode is connected to a drain of the access transistor, the plurality of memory cells being placed in a matrix shape in column and row directions, a sense amplifier circuit connected to the source of the access transistor via the bit line, a bit-line precharge voltage generating circuit for generating a bit-line precharge voltage lower than a sense amplifier supply voltage to be supplied to the sense amplifier circuit and supplying the generated bit-line precharge voltage to the bit line, and a cell plate voltage generating circuit for generating a cell plate voltage set to be lower than the bit-line precharge voltage and supplying the generated cell plate voltage to a plate electrode of the capacitor.Type: ApplicationFiled: October 17, 2007Publication date: April 24, 2008Inventor: Masahisa Iida
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Publication number: 20060179378Abstract: In this semiconductor integrated circuit, outputs of a fuse for power supply level adjustment and an internal register are selectively switched by a selector, and a selected output is inputted to a reference voltage generating circuit. Hence, the same reference voltage can be generated before and after blowing the fuse. An internal power supply voltage is generated based on this reference voltage. That makes it possible to output the same internal power supply voltage as that after blowing the fuse by using the output of the internal register before blowing the fuse. As the result of this, a redundant relief determination test using the internal power supply can be performed, and by executing a test at the same speed as that of an actual operation using BIST, an error between the internal voltages during a test and during an actual operation can be eliminated, thus achieving a highly accurate redundant relief determination of a marginal bit.Type: ApplicationFiled: January 25, 2006Publication date: August 10, 2006Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.Inventors: Masahisa Iida, Yuji Yamasaki
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Patent number: 7002866Abstract: In a single intersection type (open bit line type) dynamic RAM, sub-arrays are disposed to the left and right sides of a sense amplifier column placed at the center. Each sub-array has a multiplicity of dynamic memory cells. In the subarrays located to the left and right of the sense amplifier column, bit lines in the same row constitute a complementary bit line pair. In each subarray, shielding wiring patterns that are formed parallel to, and in the same wiring layer of, these bit lines are disposed between the bit lines. All of these wiring patterns are set at a fixed potential, such as a power supply potential. Thus, interference noise between adjacent bit lines is effectively reduced.Type: GrantFiled: March 14, 2005Date of Patent: February 21, 2006Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Masanobu Hirose, Masahisa Iida, Kiyoto Ohta
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Publication number: 20050157527Abstract: In a single intersection type (open bit line type) dynamic RAM, sub-arrays are disposed to the left and right sides of a sense amplifier column placed at the center. Each sub-array has a multiplicity of dynamic memory cells. In the subarrays located to the left and right of the sense amplifier column, bit lines in the same row constitute a complementary bit line pair. In each subarray, shielding wiring patterns that are formed parallel to, and in the same wiring layer of, these bit lines are disposed between the bit lines. All of these wiring patterns are set at a fixed potential, such as a power supply potential. Thus, interference noise between adjacent bit lines is effectively reduced.Type: ApplicationFiled: March 14, 2005Publication date: July 21, 2005Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.Inventors: Masanobu Hirose, Masahisa Iida, Kiyoto Ohta
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Patent number: 6914835Abstract: There is provided a semiconductor memory device in which a bit line precharge operation is increased in speed, and a layout area is reduced. P-channel transistors (206, 207) that function as switches are provided in a precharge voltage pumping circuit (105) included in a bit line precharge voltage generation unit. This enhances a pumping efficiency, and reduces a capacitance area of a pumping capacitor (200).Type: GrantFiled: February 24, 2004Date of Patent: July 5, 2005Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Toshihiro Nakamura, Kiyoto Ota, Masahisa Iida, Kenichi Origasa
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Patent number: 6898109Abstract: In a single intersection type (open bit line type) dynamic RAM, sub-arrays are disposed to the left and right sides of a sense amplifier column placed at the center. Each sub-array has a multiplicity of dynamic memory cells. In the subarrays located to the left and right of the sense amplifier column, bit lines in the same row constitute a complementary bit line pair. In each subarray, shielding wiring patterns that are formed parallel to, and in the same wiring layer of, these bit lines are disposed between the bit lines. All of these wiring patterns are set at a fixed potential, such as a power supply potential. Thus, interference noise between adjacent bit lines is effectively reduced.Type: GrantFiled: November 20, 2002Date of Patent: May 24, 2005Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Masanobu Hirose, Masahisa Iida, Kiyoto Ohta
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Publication number: 20040174726Abstract: There is provided a semiconductor memory device in which a bit line precharge operation is increased in speed, and a layout area is reduced. P-channel transistors (206, 207) that function as switches are provided in a precharge voltage pumping circuit (105) included in a bit line precharge voltage generation unit. This enhances a pumping efficiency, and reduces a capacitance area of a pumping capacitor (200).Type: ApplicationFiled: February 24, 2004Publication date: September 9, 2004Applicant: Matsushita Electric Industrial Co., Ltd.Inventors: Toshihiro Nakamura, Kiyoto Ota, Masahisa Iida, Kenichi Origasa
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Publication number: 20030095429Abstract: In a single intersection type (open bit line type) dynamic RAM, sub-arrays are disposed to the left and right sides of a sense amplifier column placed at the center. Each sub-array has a multiplicity of dynamic memory cells. In the subarrays located to the left and right of the sense amplifier column, bit lines in the same row constitute a complementary bit line pair. In each subarray, shielding wiring patterns that are formed parallel to, and in the same wiring layer of, these bit lines are disposed between the bit lines. All of these wiring patterns are set at a fixed potential, such as a power supply potential. Thus, interference noise between adjacent bit lines is effectively reduced.Type: ApplicationFiled: November 20, 2002Publication date: May 22, 2003Applicant: Matsushita Electric Industrial Co., Ltd.Inventors: Masanobu Hirose, Masahisa Iida, Kiyoto Ohta
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Patent number: 6493282Abstract: A semiconductor integrated circuit includes: a first n-well defined in a p-type semiconductor region; word lines; data lines; and a DRAM array. In the array, memory cells are arranged in matrix over the first n-well. Each memory cell includes a p-channel MOS access transistor and a capacitor. The access transistor has its gate connected to an associated one of the word lines, its source connected to an associated one of the data lines and its drain connected to the capacitor. The integrated circuit further includes: a row of sense amplifiers coupled to the data lines; a word line driver for driving the word lines; and a power supply circuit. The power supply circuit receives an external supply voltage, generates internal supply voltages by stepping down the external supply voltage and then applies the internal supply voltages to the sense amplifiers, word line driver and first n-well.Type: GrantFiled: September 6, 2001Date of Patent: December 10, 2002Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Masahisa Iida, Kiyoto Oota, Yuji Yamasaki, Hakuhei Kawakami