Byte writeable memory with bit-column voltage selection and column redundancy
AssigneeFreescale Semiconductor, Inc.
InventorAndrew C. Russell
Life of this patent
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Abstract
A method for accessing a memory comprising a first set of bit columns, a second set of bit columns, and a redundant set of bit columns, wherein any one of the redundant set of bit columns can be substituted for one of the first set of bit columns or one of the second set of bit columns and wherein each of the bit columns can receive a read voltage or a write voltage, is provided. The method includes during a write operation to the first set of bit columns, providing the write voltage to one of the redundant set of bit columns, if the one of the redundant set of bit columns has been substituted for one of the first set of bit columns, otherwise providing the read voltage to the redundant set of bit columns.
Claims15
A method for accessing a memory comprising a first set of bit columns, a second set of bit columns, and a redundant set of bit columns, wherein any one of the redundant set of bit columns can be substituted for one of the first set of bit columns or one of the second set of bit columns and wherein each of the bit columns can receive a read voltage or a write voltage, the method comprising:
- during a write operation to the first set of bit columns, providing the write voltage to one of the redundant set of bit columns, if the one of the redundant set of bit columns has been substituted for one of the first set of bit columns, otherwise providing the read voltage to the redundant set of bit columns, wherein the write voltage is lower than the read voltage, such that during the write operation if the one of the redundant set of bit columns has been substituted for one of the first set of bit columns, the substituted bit column receives a lower voltage than otherwise.
A method for accessing a memory comprising a first set of bit columns, a second set of bit columns, and a redundant set of bit columns, wherein any one of the redundant set of bit columns can be substituted for one of the first set of bit columns or one of the second set of bit columns and wherein each of the bit columns can receive a read voltage or a write voltage, the method comprising:
- during a write operation to the first set of bit columns, decoupling at least one of a bitcell in the one of the redundant set of bit columns from the write voltage, if the one of the redundant set of bit columns has been substituted for one of the first set of bit columns, otherwise providing the read voltage to the redundant set of bit columns, wherein the memory is a byte writeable memory such that in response to an assertion of one of a plurality of write byte enable signals, a byte size data can be written to the memory;
- and
- determining to which byte a particular redundant bit belongs to by deriving a write byte select signal from a decoder coupled to a fuse block.
A memory comprising a first set of bit columns, a second set of bit columns, and a redundant set of bit columns, wherein any one of the redundant set of bit columns can be substituted for one of the first set of bit columns or one of the second set of bit columns and wherein each of the bit columns can receive a read voltage or a write voltage, the memory comprising:
- a component configured for during a write operation to the first set of bit columns, providing the write voltage to one of the redundant set of bit columns if the one of the redundant set of bit columns has been substituted for one of the first set of bit columns and providing the read voltage to a remaining redundant set of bit columns;
- and during a read operation of the first set of bit columns, providing the read voltage to the first set of bit columns, the second set of bit columns, and the redundant set of bit columns, wherein the redundant set of bit columns is used to repair the memory when a bit column of the memory is defective and wherein the second set of bit columns is adjacent to the redundant set of bit columns, and wherein the redundant set of bit columns is used to repair the memory by blowing at least one fuse corresponding to the redundant set of bit columns.
Dependencies are inferred from the claim text.