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:
Feb. 03, 2015
Filed:
Jul. 30, 2012
Daniel Jacob Fainstein, Hopewell Junction, NY (US);
Chandrasekharan Kothandaraman, Hopewell Junction, NY (US);
Daniel Jacob Fainstein, Hopewell Junction, NY (US);
Chandrasekharan Kothandaraman, Hopewell Junction, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Methods and circuits for undiscoverable physical chip identification are disclosed. Embodiments of the present invention provide an intrinsic bit element that comprises two transistors. The two transistors form a pair in which one transistor has a wide variability in threshold voltage and the other transistor has a narrow variability in threshold voltage. The wide variability is achieved by making a transistor with a smaller width and length than the other transistor in the pair. The variation of the threshold voltage of the wide variability transistor means that in the case of copies of intrinsic bit elements being made, some of the 'copied' wide variability transistors will have significantly different threshold voltages, causing some of the intrinsic bit elements of a copied chip to read differently than in the original chip from which they were copied.