


US 6,345,000
Flash memory permitting simultaneous read/write and erase operations in a single memory array
- Filed
- November 25, 1998
- Granted
- February 5, 2002
- Assignee
- Sandisk
- Inventors
- Sau C. Wong, Hock C. So, Cheng-Yuan Michael Wang, Roger Ying Kuen Lo
Abstract
A non-volatile Flash memory simultaneously performs an erase operation and a write or read operation in the same array of memory cells. The memory has a row based sector architecture, i.e., sectors that contain one or more complete rows of memory cells. During an erase operation, an erase voltage applied to the source lines for one or more rows corresponding to a sector does not affect write or read operations being performed in other sectors, i.e., other rows. Similarly, voltages applied to row lines for access to a memory cell have no effect on the erase operation being performed in another sector. A column line voltage applied for access to a memory cell has little affect on the erase operation. The memory can implement a look-ahead erase for a continuous reading or writing operation.