Patent ID: 7633800

Claim:
A method comprising: transferring normal data bytes and redundant column data bytes from a Flash memory chip into a page register in the Flash memory chip, wherein the redundant column data bytes contain one or more correct bits for corresponding defective FLASH memory cells; transferring to a shift register in a companion control chip the redundant column data bytes from the page register in the Flash memory chip, the companion control chip being separated from the Flash memory chip; fetching into the companion control chip the normal data bytes from the page register of the FLASH memory chip; checking in the companion control chip if an address for a fetched normal data byte is for a defective memory location; if none of the bits of a fetched normal data byte is from a defective memory cell, storing that normal data byte in a page register in the companion control chip; if at least one of bits of the fetched normal data byte is from a defective memory cell, combining in the companion control chip the normal data byte with a corresponding redundant data byte to provide a correct data byte with correct bits for an external user.