Patents by Inventor Kazuto Oku

Kazuto Oku 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).

  • Patent number: 11209993
    Abstract: Apparatus and methods implement a physical unclonable function (PUF) from NAND operations. A NAND flash memory device may generate an unclonable natural random sequence of bits based on a threshold voltage of a plurality of cells in a memory cell array. The unclonable natural random sequence may be stored starting at an address of the memory cell array. A selected subsequence of the unclonable natural random sequence may be stored in a first set of data latches, and target data may be stored in a second set of data latches. The NAND flash memory device may generate a physical unclonable function (PUF) output by applying an XOR operation to the target data and the selected subsequence. The PUF output may be stored in a set of registers or provided to a memory controller to be used for secure applications such as secure identity detection and secure data transfer.
    Type: Grant
    Filed: March 24, 2020
    Date of Patent: December 28, 2021
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yuki Fujita, Kazuto Oku, Kyosuke Matsumoto
  • Publication number: 20210303182
    Abstract: Apparatus and methods implement a physical unclonable function (PUF) from NAND operations. A NAND flash memory device may generate an unclonable natural random sequence of bits based on a threshold voltage of a plurality of cells in a memory cell array. The unclonable natural random sequence may be stored starting at an address of the memory cell array. A selected subsequence of the unclonable natural random sequence may be stored in a first set of data latches, and target data may be stored in a second set of data latches. The NAND flash memory device may generate a physical unclonable function (PUF) output by applying an XOR operation to the target data and the selected subsequence. The PUF output may be stored in a set of registers or provided to a memory controller to be used for secure applications such as secure identity detection and secure data transfer.
    Type: Application
    Filed: March 24, 2020
    Publication date: September 30, 2021
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Yuki Fujita, Kazuto Oku, Kyosuke Matsumoto