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:
Oct. 10, 2006
Filed:
Aug. 26, 2004
Lim Eng Sin, Singapore, SG;
Lim Eng Sin, Singapore, SG;
FTD Solutions Pte. Ltd., Singapore, SG;
Abstract
This sensor circuit and method for defending against tampering with an integrated circuit die uses metal wire loops to protect the circuitry. In addition, these metal wire loops have several via pairs along its length. One of the vias of the via pair goes to a NAND gate which detects a break in a section of a metal wire loop. A second via of the via pair is used to periodically discharge a metal wire loop to remove residual charge, in preparation for charging the metal wire loop and detecting any uncharged section. A given integrated circuit can have one or more metal wire loops on top of the circuitry to be protected. Each metal wire loop has one or more NAND gates. These outputs of the NAND gates can be fed into OR gates to produce an overall signal which activates an alarm or other security action such as erasure of electrically erasable programmable read only memory (EEPROM).