Robust Sector ID Scheme for Tracking Dead Sectors to Automate Search and Copydown

摘要

A brownout tolerant EEPROM emulator (18) manages memory operations at a volatile memory (20) and non-volatile memory (24) using a plurality of sector status bits (451) and forward/reverse skip flags (452, 453) stored in a sector identification record (45) of each sector to define a plurality of status indicators arranged sequentially to specify a plurality of sector configuration states for each memory sector, and to automatically bypass one or more dead sectors in the non-volatile memory array during forward copydown and reverse search operations.

主权项

1. A method of emulating EEPROM memory in non-volatile memory, comprising:
programming a sector identification record for a first non-volatile memory sector by storing a first status indicator in the sector identification record upon performing a first program operation on the first non-volatile memory sector; and programming the sector identification record for the first non-volatile memory sector by storing a second status indicator in the sector identification record as part of a plurality of sector status bits upon performing a second program operation on the first non-volatile memory sector, where the plurality of sector status bits are defined by a plurality of status indicators arranged sequentially to specify a plurality of sector configuration states for the first non-volatile memory sector, and where the first and second program operations are required to change a sector configuration state for the first non-volatile memory sector.