Freescale Semiconductor,inc.

Nxp Usa, Inc.

Daniel L Andre

Ross Sinclair Scouller

Jeffrey C Cunningham

Stephen F McGinty

Tim J Coots

Frank Kelsey Baker, Jr

The present disclosure provides methods and circuits for managing failing sectors in a non-volatile memory. A record address and a read control signal are received, where the record address identifies a location in the non-volatile memory. The record address is compared with a plurality of dead sector addresses, where the dead sector addresses correspond to a subset of sectors located in the non-volatile memory. Data located at the record address is determined to be invalid in response to a combination of a first detection that the record address matches one of the dead sector addresses and a second detection that the read control signal indicates a read operation is requested to be performed on the non-volatile memory.

High voltage failure recovery for emulated electrically erasable (EEE) memory system

Methods and systems are disclosed for code protection in non-volatile memory (NVM) systems. Information stored within NVM memory sectors, such as boot code or other code blocks, is protected using lockout codes and lockout keys written in program-once memory areas within the NVM systems. Further, lockout codes can be combined into a merged lockout code that can be stored in a merged protection register. The merged protection register is used to control write access to protected memory sectors. Lockout code/key pairs are written to the program-once area when a memory sector is protected. The program-once area, which stores the lockout code/key pairs, is not readable by external users. Once protected, a memory sector can not be updated without the lockout code/key pair.

Systems and methods for code protection in non-volatile memory systems

A method of transferring data from a non-volatile memory (NVM) having a plurality of blocks of an emulated electrically erasable (EEE) memory to a random access memory (RAM) of the EEE includes accessing a plurality of records, a record from each block. A determination is made if any of the data signals of the first data signals are valid and thereby considered valid data signals. If there is only one or none that are valid, the valid data, if any is loaded into RAM and the process continues with subsequent simultaneous accesses. If more than one is valid, then the processes is halted until the RAM is loaded with the valid data, then the method continues with subsequent simultaneous accesses of records.

Emulated electrically erasable memory parallel record management

A system includes an emulation memory having a first sector of non-volatile memory for storing information, in which the non-volatile memory includes a plurality of records. It is determined if a last record written of the plurality of records is a compromised record, if the last record written is not a compromised record, a next write is performed to a record of the plurality of records that is next to the last record written. If the last record written is a comprised record, an address of the compromised record is determined, valid data for the address of the compromised record is written into the record of the plurality of records that is next to the compromised record, and data is written into a record that is next to the record of the plurality of records that is next to the compromised record.

Recovery scheme for an emulated memory system

A method of storing information at a non-volatile memory includes storing a status bit prior to storing data at the memory. A second status bit is stored after storing of the data. Because the storage of data is interleaved with the storage of the status bits, a brownout or other corrupting event during storage of the data will likely result in a failure to store the second status bit. Therefore, the first and second status bits can be compared to determine if the data was properly stored at the non-volatile memory.

Non-volatile memory controller device and method therefor

A method of storing information at a non-volatile memory includes storing a first status bit at a sector header of the memory prior to erasing a sector at the memory. A second status bit is stored after erasing of the sector. Because the erasure of the sector is interleaved with the storage of the status bits, a brownout or other corrupting event during erasure of the record will likely result in a failure to store the second status bit. Therefore, the first and second status bits can be compared to determine if the data was properly erased at the non-volatile memory. Further, multiple status bits can be employed to indicate the status of other memory sectors, so that a difference in the status bits for a particular sector can indicate a brownout or other corrupting event.

Non-volatile memory device and method therefor

An emulated electrically erasable memory system includes a random access memory (RAM) and a non-volatile memory (NVM). A write access to the RAM is received which provides first write data and a first address, where the first write data is stored in the RAM at the first address, and a currently filling sector of the NVM is updated to store both the first write data and the first address as a first record. In response to the write access, based on whether there are any remaining active records in an oldest filled sector of the NVM, a portion of an erase process or a transfer of up to a predetermined number of active records from the oldest filled sector to the currently filling sector is performed. The predetermined number of active records is less than a maximum number of total records that may be stored within the oldest filled sector.

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Austin, TX, United States of America

Daniel L Andre