abstract |
A non-volatile memory device includes the ability to recover data in event of a program failure without having to maintain a copy of the data until the write is completed. As the integrity of the data can thus be maintained with having to save a copy, buffers can be freed up for other data or even eliminated, reducing the amount of controller space that needs to devoted data buffering. In exemplary embodiments, the data is recovered by logically combining the verify data for the (failed) write process maintained in data latches with the results of one or more read operations to reconstitute the data. The exemplary embodiments are for memory cells storing multi-state data, both in the format of independent upper page, lower page form, as well as in 2-bit form. This can be accomplished by a state machine and data latches in the sense amp area on the memory, without use of the controller. |