Efficient Use of Redundant Bit Lines for Yield Optimization
Original Publication Date: 1989-May-01
Included in the Prior Art Database: 2005-Jan-27
By using an architecture that permits a single data line to pass through all input/output (I/O) arrays and by the addition of fuses for decoding failed bit lines in all possible arrays on a chip, redundant bit lines may replace any failed bit line in any array. Thus, redundant bit lines not needed for one array are available as replacements for an array having more than one failed bit line. Referring to the figure, a memory is segmented into four arrays 2, 4, 6, and 8 and has 4 groups of redundant bit lines accessible through switches contained in blocks 10, 12, 14, and 16. Data lines 32, 34, 36, 38 and redundant data lines 28, 30, 40, 42 can be connected to all arrays through multiplexers (MUXs) 18, 20, 22 via lines 44, 46, 48, 50.