Non-volatile semiconductor memory device having a password protection function
US7360049B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 20, 2006 |
| Grant date | Apr 15, 2008 |
| Priority date | — |
| Expiry date | Nov 2, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F21/79
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a nonvolatile semiconductor memory device according to the present invention, a password protection function is enabled or disabled based on a first specified value M and a second state specified value P such that when both of the first specified value M and the second state specified value P are in a set state, the password protection function is enabled and when at least the second specified value P is in a reset state, the password protection function is disabled, and the first state specified value M maintains a previous state and the second state specified value P follows the state of the first state specified value M in response to a reset operation, and the cancel operation to shift the second state specified value P to the reset state can be performed only when the password is inputted correctly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.