Patent ID: 7656695
Filing Date: 2010-02-02
Classification: G11C

Abstract:
1. An electronic fuse system comprising: a fuse read only memory (ROM) having one or more blocks of memory, each block of memory having a plurality of words with at least one word of the plurality of words containing security bits associated with a respective block; an electronic fuse controller in communication with the fuse ROM and one or more external devices that are configured to request one or more words that reside in the fuse ROM from the electronic fuse controller; and at least one security register that includes indication bits that provide an indication whether security bits have been obtained for a respective block of memory of the fuse ROM after a power down and power up cycle, wherein the electronic fuse controller, in response to a request to read a word from a block of memory from an external device, provides the requested word if an indication bit associated with the block of memory is set or reads the at least one word of the plurality of words containing security bits associated with the block of memory if the indication bit associated with the block of memory is not set, sets the indication bit associated with the block of memory, and provides the requested word.