Patent · US Expired

Security device for a semiconductor chip

US5881155A · kind A · utility

23Cited by
8References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 31, 1997
Grant dateMar 9, 1999
Priority date
Expiry dateMar 31, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/01019
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Security device for preventing access to confidential information stored in a semiconductor chip, or protected chip. The security device comprises a second semiconductor chip, or protective chip, with the two chips facing each other and being coupled to each other by communication terminals. The protected chip is coupled to external circuits via the protective chip, and the two semiconductor chips are separated by a semiconductor resin having a non-homogeneous electrical resistivity. The protective chip is provided with means for measuring a plurality of resistances through the semiconductor resin and with means for determining, at least from the measured resistances, an encryption key intended to be communicated to the protect chip to protect the confidential information.

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