Abstract: According to one embodiment, a decoding device comprises a converter configured to convert read data to first likelihood information by using a first conversion table, a decoder which decodes the first likelihood information, a controller which outputs a decoding result of the decoder when the decoder succeeds decoding, and a creator module which creates a second conversion table based on the decoding result when the decoder fails decoding. When the second conversion table is created, at least a part of the decoding result is converted to second likelihood information by using the second conversion table the second likelihood information is decoded.

Abstract: A semiconductor device of an embodiment includes a seed generator circuit configured to generate a seed from inputted data by using first random number sequence data generated by an XorShift circuit; and a random number generator circuit configured to receive the seed as input to generate second random number sequence data by a second XorShift circuit.

Abstract: The present embodiments relate to methods for maintaining steady and high performance programming of non-volatile memory devices such as NAND-type flash devices. According to certain aspects, embodiments provide adaptive control of programming parameters over the lifespan of a NAND flash device so as to maintain write performance and obtain high endurance.

Abstract: According to one embodiment, a decoding device comprises a converter configured to convert read data to first likelihood information by using a first conversion table, a decoder which decodes the first likelihood information, a controller which outputs a decoding result of the decoder when the decoder succeeds decoding, and a creator module which creates a second conversion table based on the decoding result when the decoder fails decoding. When the second conversion table is created, at least a part of the decoding result is converted to second likelihood information by using the second conversion table the second likelihood information is decoded.

Abstract: A randomizer includes a first pseudorandom number generator, a second pseudorandom number generator, and a first logic circuit configured to output a pseudorandom sequence by carrying out an operation on a pseudorandom sequence generated by the first pseudorandom number generator and a pseudorandom sequence generated by the second pseudorandom number generator, and a second logic circuit configured to randomize a data string input to the randomizer based on the pseudorandom sequence output by the first logic circuit.

Abstract: A memory system includes a first memory, a second memory, and a first circuit. The first memory includes a memory cell array including memory cell transistors, and a peripheral circuit configured to read data of a plurality of bits stored in a memory cell transistor of the memory cell array based on a comparison between threshold voltages of the memory cell transistor and at least a part of n determination voltages (n?3). The first circuit is configured to calculate an estimated value of each of n?m determination voltages based on values of m determination voltages (2?m?n?1) among the n determination voltages, and calculate a difference between a value of each of the n?m determination voltages and a corresponding estimated value. The second memory is configured to store values of the m determination voltages and the difference for each of the n?m determination voltages.

Abstract: A nonvolatile memory includes a memory array, a sensor for measuring a temperature, an interface through which a write command is to be received, and a control circuit. The control circuit is configured to write information of the temperature measured by the sensor in a data storing area of the memory array in which user data associated with the write command is not capable of being written into, when writing the user data in the memory array in response to the received write command.

Abstract: The present embodiments relate to methods for maintaining steady and high performance programming of non-volatile memory devices such as NAND-type flash devices. According to certain aspects, embodiments provide adaptive control of programming parameters over the lifespan of a NAND flash device so as to maintain write performance and obtain high endurance.

Abstract: The present embodiments relate to methods for estimating bit error rates (BERs) associated with a flash memory. According to certain aspects, embodiments provide estimating the BER of multi-bit flash memories during the programming of the flash memory, and providing the estimated BER in a readable status register of the flash memory, thereby improving the speed of programming of the flash memory.

Abstract: The present embodiments relate to methods for maintaining steady and high performance programming of non-volatile memory devices such as NAND-type flash devices. According to certain aspects, embodiments provide adaptive control of programming parameters over the lifespan of a NAND flash device so as to maintain write performance and obtain high endurance.

Abstract: A memory system includes a first memory, a second memory, and a first circuit. The first memory includes a memory cell array including memory cell transistors, and a peripheral circuit configured to read data of a plurality of bits stored in a memory cell transistor of the memory cell array based on a comparison between threshold voltages of the memory cell transistor and at least a part of n determination voltages (n?3). The first circuit is configured to calculate an estimated value of each of n?m determination voltages based on values of m determination voltages (2?m?n?1) among the n determination voltages, and calculate a difference between a value of each of the n?m determination voltages and a corresponding estimated value. The second memory is configured to store values of the m determination voltages and the difference for each of the n?m determination voltages.

Abstract: A randomizer includes a first pseudorandom number generator, a second pseudorandom number generator, and a first logic circuit configured to output a pseudorandom sequence by carrying out an operation on a pseudorandom sequence generated by the first pseudorandom number generator and a pseudorandom sequence generated by the second pseudorandom number generator, and a second logic circuit configured to randomize a data string input to the randomizer based on the pseudorandom sequence output by the first logic circuit.

Abstract: A randomizer includes a first pseudorandom number generator, a second pseudorandom number generator, and a first logic circuit configured to output a pseudorandom sequence by carrying out an operation on a pseudorandom sequence generated by the first pseudorandom number generator and a pseudorandom sequence generated by the second pseudorandom number generator, and a second logic circuit configured to randomize a data string input to the randomizer based on the pseudorandom sequence output by the first logic circuit.

Abstract: A semiconductor memory device includes a NAND memory including a plurality of blocks, each of which is a unit of data erasing, and a controller. The controller is configured to select an initial value from a group of initial values, based on an address of the NAND memory in which data are to be written, set a value corresponding to the selected initial value to a linear feedback shift register circuit, randomize the data using an output value of the linear feedback shift register circuit, and write the randomized data to the address of the NAND memory. A size of each of the blocks S is smaller than 2n-1 bytes, n being a number of registers included in the linear feedback shift register circuit.

Abstract: The present embodiments relate to methods for estimating bit error rates (BERs) associated with a flash memory. According to certain aspects, embodiments provide estimating the BER of multi-bit flash memories during the programming of the flash memory, and providing the estimated BER in a readable status register of the flash memory, thereby improving the speed of programming of the flash memory.

Abstract: A semiconductor memory device includes a NAND memory including a plurality of blocks, each of which is a unit of data erasing, and a controller. The controller is configured to select an initial value from a group of initial values, based on an address of the NAND memory in which data are to be written, set a value corresponding to the selected initial value to a linear feedback shift register circuit, randomize the data using an output value of the linear feedback shift register circuit, and write the randomized data to the address of the NAND memory. A size of each of the blocks S is smaller than 2n-1 bytes, n being a number of registers included in the linear feedback shift register circuit.

Abstract: According to one embodiment, a semiconductor device comprises an integrated circuit having a plurality of current modes different in operation current; a voltage sensor that detects a voltage in use by the integrated circuit; a BIST control circuit that generates BIST patterns different in the operation current and creates a flag indicating the success or failure of a BIST corresponding to the operation current based on the result of detecting the voltage while the integrated circuit is made to operate based on the BIST pattern; and a storing unit that stores the flag. The integrated circuit sets the current mode based on the flag.

Abstract: According to one embodiment, a temperature of a non-volatile memory or an ambient temperature of the non-volatile memory is acquired. A distribution of a threshold voltage, which is corrected according to the acquired temperature, is acquired from the non-volatile memory. Read voltages related to the reading of data are detected from the distribution. Error correction is performed for data read from the non-volatile memory, using the read voltages. The detected read voltages are separately corrected on the basis of the acquired temperature when the error correction has failed.

Abstract: A semiconductor memory device includes a NAND memory including a plurality of blocks, each of which is a unit of data erasing, and a controller. The controller is configured to select an initial value from a group of initial values, based on an address of the NAND memory in which data are to be written, set a value corresponding to the selected initial value to a linear feedback shift register circuit, randomize the data using an output value of the linear feedback shift register circuit, and write the randomized data to the address of the NAND memory. A size of each of the blocks S is smaller than 2n?1 bytes, n being a number of registers included in the linear feedback shift register circuit.

Abstract: A randomizer includes a first pseudorandom number generator, a second pseudorandom number generator, and a first logic circuit configured to output a pseudorandom sequence by carrying out an operation on a pseudorandom sequence generated by the first pseudorandom number generator and a pseudorandom sequence generated by the second pseudorandom number generator, and a second logic circuit configured to randomize a data string input to the randomizer based on the pseudorandom sequence output by the first logic circuit.