Code protection in microcontroller with EEPROM fuses
US5469557A · kind A · utility
128Cited by
3References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1993 |
| Grant date | Nov 21, 1995 |
| Priority date | — |
| Expiry date | Mar 5, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/22
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A semiconductor microcontroller device is adapted to control the operation of an external system. The device includes a CPU, program memory for storing instructions to be executed by the CPU to perform its control functions, and data memory for storing data for selective retrieval by the CPU. The contents of either memory are code protected by an EEPROM fuse, and are automatically erased if the code protect state of the EEPROM fuse is sought to be reset, and the EEPROM fuse is reset only after the erasure of the memory contents.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.