Title:
NONVOLATILE SEMICONDUCTOR STORAGE DEVICE, AND OPERATION CONDITION CONTROL METHOD IN NONVOLATILE SEMICONDUCTOR STORAGE DEVICE
Document Type and Number:
Japanese Patent JP2013125575
Kind Code:
A
Abstract:
To provide a nonvolatile semiconductor storage device which can detect deterioration states of characteristics of memory cells for individual blocks of a flash memory, and can set an operation condition of the flash memory according to the deterioration states of the individual blocks.
A nonvolatile semiconductor storage device 1 includes monitoring erase time (tERS) of individual blocks in a flash memory 20, storing a block address of the block when the erase time (tERS) exceeds a determination reference value, and changing an operation condition of the flash memory 20 to a predetermined operation condition when the block is accessed.
Inventors:
KAWAMURA SHOICHI
Application Number:
JP2011275701A
Publication Date:
June 24, 2013
Filing Date:
December 16, 2011
Export Citation:
Assignee:
SAMSUNG YOKOHAMA RES INST CO
International Classes:
G11C16/02; G11C29/12
Attorney, Agent or Firm:
Masatake Shiga
Suzuki Mitsuyoshi
Tomoo Katsumata
Suzuki Mitsuyoshi
Tomoo Katsumata