Data restoration in case of page-programming failure

Abstract

The present invention discloses systems and methods for restoring data in flash memory after an operational failure. The method includes: setting bits of a data buffer in accordance with the data; programming a plurality of memory cells in accordance with the data buffer; and upon failure of the programming step, restoring the data buffer to be set in accordance with the data, wherein the restoring is based only on a present state of the data buffer and on a present state of the plurality of memory cells. A memory device includes: at least one cell; and a controller operative to store data in at least one cell by steps including those described in the method above. The system includes: a memory device that includes at least one cell; and a processor operative to store data in at least one cell by steps including those described in the method above.

1 . A method for storing data, the method comprising the steps of: 
 (a) setting bits of a data buffer in accordance with the data;    (b) programming a plurality of memory cells in accordance with said data buffer; and    (c) upon failure of said programming step, restoring said data buffer to be set in accordance with the data, wherein said restoring is based only on a present state of said data buffer and on a present state of said plurality of memory cells.    
     
     
         2 . The method of  claim 1 , wherein said memory cells are flash memory cells.  
     
     
         3 . The method of  claim 1 , wherein said memory cells are single-level memory cells.  
     
     
         4 . The method of  claim 1 , wherein said memory cells are multi-level memory cells.  
     
     
         5 . The method of  claim 1 , wherein said step of restoring is performed by applying a logic operation between said bits in said data buffer and corresponding memory cell bits.  
     
     
         6 . The method of  claim 1 , wherein said step of restoring includes: 
 (i) detecting memory cell bits that have been successfully programmed during said programming step; and    (ii) copying said memory cell bits to corresponding locations in said data buffer.    
     
     
         7 . A memory device comprising: 
 (a) at least one cell; and    (b) a controller operative to store data in said at least one cell by steps including: 
 (i) setting bits of a data buffer in accordance with said data;  
 (ii) programming a plurality of memory cells in accordance with said data buffer; and  
 (iii) upon failure of said programming step, restoring said data buffer to be set in accordance with said data, wherein said restoring is based only on a present state of said data buffer and on a present state of said plurality of memory cells.  
   
     
     
         8 . A system for storing data, the system comprising: 
 (a) a memory device that includes at least one cell; and    (b) a processor operative to store data in said at least one cell by steps including: 
 (i) setting bits of a data buffer in accordance with said data;  
 (ii) programming a plurality of memory cells in accordance with said data buffer; and  
 (iii) upon failure of said programming step, restoring said data buffer to be set in accordance with said data, wherein said restoring is based only on a present state of said data buffer and on a present state of said plurality of memory cells.