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Nonvolatile semiconductor memory device

  • US 6,549,464 B2
  • Filed: 07/02/2002
  • Issued: 04/15/2003
  • Est. Priority Date: 05/14/1997
  • Status: Expired due to Term
First Claim
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1. A nonvolatile semiconductor memory device comprising:

  • a plurality of nonvolatile semiconductor memory cells, each capable of storing n-value data, where n is a natural number greater than 2; and

    a data-programming circuit for performing a program operation in which program pulses are applied to said plurality of nonvolatile semiconductor memory cells to program n-value data into said plurality of nonvolatile semiconductor memory cells, performing a program verification operation to determine whether or not the n-value data has been programmed into said plurality of nonvolatile semiconductor memory cells and repeating the program operation and the program verification operation, wherein each of said program pulses has a predetermined pulse width in accordance with a value of the n-value data to be programmed into a corresponding memory cell.

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