Patent ID: 6611445
Filing Date: 2003-08-26
Classification: G11C

Abstract:
A content addressable memory (CAM) comprising:a plurality of CAM words; one or more spare CAM word serving as a redundant circuit; a defective-CAM-word address storage section for holding information indicating whether there is one or more defective CAM word in the plurality of CAM words, and if there is one or more defective CAM word, address information of the defective CAM word; a shift control circuit for controlling such that the addresses of CAM words located at lower-order addresses than the defective CAM word are shifted in a lower-order direction or in an higher-order direction by the use of the spare CAM word, according to the address information of the defective CAM word, held in the defective-CAM-word address storage section; a first shift circuit for shifting the addresses of CAM words located at lower-order addresses than i-th (i: integer equal to 1 or more) defective CAM word in the lower-order direction by â€œiâ€  according to the control of the shift control circuit at a read/write access of data; and a second shift circuit for shifting the addresses of the CAM words located at lower-order addresses than the i-th defective CAM word in the higher-order direction by â€œiâ€  according to the control of the shift control circuit at a search operation.