Patent · US Expired

Circuit and method for protecting electronic devices

US6934854B2 · kind B2 · utility

2Cited by

4References

10Claims

0Family size

Assignee

Infineon Technologies AG · DE

Inventors

Eric-Roger Brücklmeier · Hersbruck, DE
Herbert Palm · Hohenkirchen, DE
Andreas Kux · Haar, DE

Key dates

Filing date	Mar 1, 2002
Grant date	Aug 23, 2005
Priority date	—
Expiry date	Feb 3, 2024

Classification

Technology area (CPC G)Physics
CPC primaryG07F7/1083
WIPO fieldControl
WIPO sectorInstruments

Abstract

The access time for the use of an electronic device, for example a chip, is prolonged after each unauthorized access attempt. The access time is determined by the time for the matching of the turn-on voltages of two floating gate cells. Before an access attempt, the turn-on voltage of one cell is set to a predefined initial value and the turn-on voltage of the other cell is set to a value which is higher in comparison and which is increased after each unauthorized access.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.