Searchline control circuit and power reduction method

摘要

A system and method for reduction of power consumed by a searchline buffer and control circuit during a CAM search-and-compare operation. The data buffer circuit samples one bit of a search word and a mask bit for driving a pair of complementary searchlines with the appropriate logic levels. The complementary searchlines are precharged to a mid-point voltage level between the high logic level voltage and the low logic level voltage during a precharge phase. The mid-point voltage level is applied on each searchline by sharing charge from the searchline at the high logic level voltage with the searchline at the low logic level voltage. Additional control logic compares the searchline data of the current search-and-compare operation with the next search-and-compare operation, to inhibit searchline precharging when both searchline data are at the same logic level.