Patent attributes
The invention provides a cache architecture that selectively powered-up a portion of data array in a pipelined cache architecture. A tag array is first powered-up, but the data array is not powered-up during this time, to determine whether there is a tag hit from the decoded index address comparing to the tag compare data. If there is a tag hit, during a later time, a data array is then powered-up at that time to enable a cache line which corresponds with the tag hit for placing onto a data bus. The power consumed by the tag represents a fraction of the power consumed by the data array. A significant power is conserved during the time in which the tag array is assessing whether a tag hit occurs while the data array is not powered-on at this point.
