05930167 is referenced by 361 patents and cites 26 patents.

A memory system including an array of flash EEPROM cells arranged in blocks of cells that are erasable together, with individual cells storing more than one bit of data as a result of operating the individual cells with more than two detectable threshold ranges or states. Any portion of the array in which data is not stored can be used as a write cache, where individual ones of the cells store a single bit of data by operating with only two detectable threshold ranges. Data coming into the memory is initially written in available blocks in two states since writing in more than two states takes significantly more time. At a later time, in the background, the cached data is read, compressed and written back into fewer blocks of the memory in multi-state for longer term storage at a reduced cost.

Title
Multi-state non-volatile flash memory capable of being its own two state write cache
Application Number
8/902776
Publication Number
5930167
Application Date
July 30, 1997
Publication Date
July 27, 1999
Inventor
Jian Chen
San Jose
CA, US
Douglas J Lee
San Jose
CA, US
Agent
Majestic Parsons Siebert & Hsue
Assignee
SanDisk Corporation
CA, US
IPC
G11C 16/04
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