Patents Examined by Gene N. Anduong
  • Patent number: 6643180
    Abstract: In a method of testing a nonvolatile semiconductor memory integrated on a semiconductor chip comprising a memory cell array, a first register that stores an address of a defective region in the memory cell array, a plurality of internal voltage generator circuits, and a second register, the second register storing a trimming value for setting an internal voltage value generated by each of the internal voltage generator circuits, the testing method carries out resetting the address of the defective region stored in the first register and the trimming value stored in the second register, and setting the address of the defective region stored in the first register and the trimming value stored in the second register to a value according to a property of each of the semiconductor chips, wherein the testing is carried out without turning a power supply off after the power supply has been turned on.
    Type: Grant
    Filed: October 2, 2001
    Date of Patent: November 4, 2003
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tamio Ikehashi, Ken Takeuchi, Toshihiko Himeno