The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 05, 1990
Filed:
Nov. 03, 1989
Serge Fruhauf, Peynier, FR;
Laurent Sourgen, Aix en Provence, FR;
SGS-Thomson Microelectronics, S.A., Gentilly, FR;
Abstract
The disclosure concerns the safety of the confidential information contained in integrated circuits. In a certain number of integrated circuit applications and, more particularly, in the circuits contained in cards known as 'chip cards', it is necessary to prohibit access by unauthorized persons to confidential information stored in a memory of the circuit. To prevent the fraudulent practice of examining the current consumption at the terminals of the integrated circuit during an operation of reading or writing in the memory, a protection circuit is used. This protection circuit actuates the simulation, according to a pseudo-random sequence generated by a generator, of current consumption values identical to those of real memory cells.