Patent ID: 7277315

Claim:
A method to reduce power consumption of a local DRAM word-line driver by building up in n stages a voltage VPP required, comprises: (1) provide n voltage boost converters, n switching means, a local word-line driver circuit, and (n−1) voltage detectors; (2) monitor the voltage on said local word-line driver; (3) use exclusively the output of a first of said voltage boost converters to build-up on a local word-line driver a first intermediate voltage VPP 1 being smaller than the boosted voltage VPP required to operate the word-line of a DRAM memory cell array until said intermediate voltage VPP 1 is reached; (4) use exclusively the output of a next of said n voltage boost converters to build-up on a local word-line driver a next voltage level assigned to the boost converter in operation, wherein said voltage is higher than the previous voltage level until said voltage level assigned is reached; (5) check if n-th voltage booster converter is in use and if negative, go to step (4), otherwise go to end.