Control gate driver circuit for a non-volatile memory and memory using same
US5721704A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 23, 1996 |
| Grant date | Feb 24, 1998 |
| Priority date | — |
| Expiry date | Aug 23, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/28
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A control gate driver circuit (900) provides a variety of voltages to a control gate (21) of a floating gate nonvolatile memory cell (10) using a single circuit. During a read mode, a bias circuit (920) and a reference transistor (925) bias a pass transistor (936) connected to the output of a level shifter (910) to be slightly conductive and thus biases control gates without the need for a charge pump. During programming, a pulse circuit (940) gradually builds the program voltage provided to cells along a selected row, allowing the use of smaller pass transistors (932, 934) and smaller capacitors in the charge pump of the supply (930). Cells in an unselected row are driven to a different voltage, decreasing junction leakage and maintaining high disturb voltage in cells in the unselected row. The control gate driver circuit (900) is implemented using only P-channel pass transistors, eliminating the need for a costly triple-well process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.