Inventors:
Sheng-Hsiung Hsueh - San Jose CA
Ganshu Ben Lee - Santa Clara CA
Loc Bao Hoang - San Jose CA
Albert V. Kordesch - San Jose CA
Assignee:
Winbond Electronics Corporation - Hsin Chu
International Classification:
G11C 1606
Abstract:
Techniques to more accurately read values stored in data cells. In an aspect, one reference cell is provided for each group of data cells having similar configuration (e. g. , similar layout and orientation). For split-gate memory cells arranged in pairs, each pair includes two data cells implemented as mirrored image of one another. Two reference cells may then be used, one reference cell for each data cell in a pair. In another aspect, the data paths for the reference and data cells for read operation are matched. This matching may be achieved by using the same circuit design for the data and reference sense amplifiers, using the same layout and orientation for the sense amplifiers, matching the lines for the two data paths, matching the structure (e. g. , length and width) and the diffusion region (e. g. , doping concentration and contact) for the sense amplifiers and lines, and so on.