Method and apparatus for reducing leakage current in a read only memory device using pre-charged sub-arrays

摘要

A method and apparatus are provided for reducing leakage current in a read only memory device. Leakage current is reduced by precharging only a portion of the columns in a read only memory array during a given read cycle. The portion of the columns that are precharged is limited to a subset of columns that includes those columns that will be read during a given read cycle. A read column address is decoded to precharge only the portion of the columns of transistors that will be read during the given read cycle. The columns of transistors can be grouped into a plurality of sub-arrays and only those sub-arrays having columns that will be read during a given read cycle are precharged during the read cycle.