PRE-CHARGE CIRCUIT OF WORD MATCH LINE OF ASSOCIATED MEMORY (CAM) AND METHOD

摘要

PROBLEM TO BE SOLVED: To reduce average power consumption in search operation of CAM without affecting performance of CAM. SOLUTION: Relating to each word accompanying bits (valid bit) indicating whether data of at the word is valid or not in CAM, a circuit is constituted so that when a valid bit indicates that the word is invalid, pre-charge is controlled so that pre-charge of a match line of the word is prohibited, and a match line is forcedly in a 'uncoincidence state'. Thereby, power consumption caused by search operation by a data word being not a search object is prevented, and power consumption of search operation of the whole CAM is reduced.