DRAM hierarchical data path
AssigneeInternational Business Machines Corporation
InventorsRichard Matick, Stanley Schuster
Life of this patent
Estimating the term…
Abstract
A hierarchical DRAM array, DRAM macro and logic chip including the DRAM macro embedded in the logic. DRAM array columns are segmented with a small number (e.g., 2-64) of cells connected to a local bit line (LBL) in each segment. Each LBL drives a sense device that drives a global read bit line (GRBL). When a cell storing a high is selected, the cell drives the LBL high, which turns the sense device on to drive the GRBL low. Segments may be used individually (as a macro) or combined with other segments sharing a common GRBL.
Claims32
A DRAM array comprising:
- a plurality of rows of DRAM cells, each of said rows being selected by a word line;
- and
- a plurality of columns of said DRAM cells, each of said columns comprising:
- a plurality of column segments, each of said column segments including DRAM cells in two or more of said plurality of rows connected to a local bit line, and
- a global bit line, contents on each said local bit line being coupled to said global bit line.
A CMOS DRAM macro comprising:
- a local bit line;
- at least two DRAM cells connected to said local bit line;
- a read device gated by said local bit line;
- and
- a global read bit line connected to a conduction terminal of said global read bit line.
A CMOS logic chip including an embedded DRAM array, said embedded DRAM array comprising:
- a plurality of rows of DRAM cells, each of said rows being selected by a word line;
- a plurality of columns of said DRAM cells, each of said columns including a plurality of column segments, each of said column segments comprising:
- a local bit line,
- at least two DRAM cells connected to said local bit line, and
- a read device gated by said local bit line;
- and
- a global read bit line in each column, read devices in said column segments in said each column being connected at a conduction terminal to said global read bit line.
Dependencies are inferred from the claim text.