Regulated negative voltage supply circuit for floating gate memory devices
US6055186A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 23, 1998 |
| Grant date | Apr 25, 2000 |
| Priority date | — |
| Expiry date | Oct 23, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/30
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A technique for regulating a negative voltage charge pump to induce Fowler-Nordheim tunneling in floating gate cells controls applied bias to compensate for variations in the supply potential VDD, temperature, and the gate coupling ratio (GCR) or other characteristics of the memory cells which depend on manufacturing processes. A supply circuit for a negative voltage includes a voltage regulator that is coupled to the negative voltage source to maintain the negative voltage at a regulated level. The regulator includes an element that establishes the regulated level according to the manufacturing processes and temperature of the device. The regulator also comprises a circuit which establishes the regulated level in response to the supply voltage. Thus, where the negative voltage generator is utilized in a floating gate memory device, the element that establishes the regulated level according to manufactured processes and temperatures comprises a floating gate transistor manufactured according to the same processes as the non-volatile memory cells in the array on the device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.