Patent · US Expired

Chip card circuit with monitored access to a test mode

US6933742B2 · kind B2 · utility

2Cited by
8References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 18, 2002
Grant dateAug 23, 2005
Priority date
Expiry dateAug 30, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/31701
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A circuit for monitoring an entry into a test mode of a chip circuit has a fusible link which can be fired via a firing transistor. A flipflop, which permits access to the test mode, is set by a resulting voltage drop, with the aid of an edge detector. The number of times the test mode has been accessed can be detected from the number of fired fusible links.

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