Method and apparatus for preventing unauthorized access to nonvolatile memory in electronic encoders having a voltage level detection circuit
US5675534A · kind A · utility
7Cited by
2References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1996 |
| Grant date | Oct 7, 1997 |
| Priority date | — |
| Expiry date | Mar 5, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/22
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
According to the present invention, a method is provided for reading data from non-volatile memory in an electronic encoding device such that unauthorized access to the data is prevented. In one embodiment, the method includes the steps of writing a first set of data to the non-volatile memory; generating a voltage detect signal during the writing, the voltage detect signal being representative of a source voltage applied to the non-volatile memory; determining whether the writing was successful by evaluating the voltage detect signal; and reading data from the non-volatile memory responsive to the determination.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.