Method for Sensing Extra Cells on Ends of Dynamic Random-Access Memory Interdigitated Arrays
Original Publication Date: 1986-Nov-01
Included in the Prior Art Database: 2005-Mar-09
Two methods are described to access previously unused dynamic random- access memory (DRAM) cells at the ends of bit line array segments wherein bit lines are interdigitated for maximum space utilization. The presence of these cells, inclusive of bit line wiring, is the result of the repetitive layout process for memory arrays. Both methods employ "folded" (half wide, double high) sense amplifier design to connect to previously unconnected bit line segments at ends of interdigitated arrays of bit lines. Fig. 1 shows a first method comprised of attaching the folded sense amplifiers 2 to previously unconnected bit line segments 4. Sense amplifiers 6 internal to the array are of normal design dimensions. Only two of the word lines are shown.