Flash memory with shortened erasing operation time
AssigneeFujitsu Limited
InventorsJunji Tomita, Kazuhide Kurosaki, Takuo Ito
Life of this patent
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Abstract
A flash memory having a nonvolatile memory cell, includes a plurality of banks each having a plurality of sectors, an erasing voltage generator circuit and a writing voltage generator circuit, wherein while an applying an erase pulse to a sector to be erased in a first bank, an erasing control is performed by, a pre-writing control is concurrently performed by applying a writing pulse to a sector to be erased in a second bank. At the time when erasing control of the sector to be erased in a first bank is finished, pre-writing control of the sector to be erased in a second bank is finished or partially finished, and thus the time required for erasing operations of the first and the second bank can be reduced.
Claims12
A flash memory having a nonvolatile memory cell, comprising:
- a plurality of banks each having a plurality of sectors, wherein
- an erasing operation for a sector to be erased includes a pre-writing control applying a writing pulse and an erasing control applying an erasing pulse thereafter, and wherein
- while the erasing control is provided to a sector to be erased in a first bank, the pre-writing control is provided to a sector to be erased in a second bank concurrently.
A flash memory having a nonvolatile memory cell, comprising:
- a plurality of banks each having a plurality of sectors, wherein
- an erasing operation for a sector to be erased includes a pre-writing control applying a writing pulse, and an erasing control applying an erasing pulse thereafter, and wherein
- while the erasing control is performed after the pre-writing control is performed to a sector to be erased in a first bank, the pre-writing control is performed to a sector to be erased in a second bank concurrently, and
- after the completion of the erasing control in the first bank and after the completion of the pre-writing control in the second bank, the erasing control is provided to the sector to be erased in the second bank.
Dependencies are inferred from the claim text.