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:
Jul. 10, 2007
Filed:
Jun. 07, 2005
David R. Hanson, Brewster, NY (US);
Dureseti Chidambarrao, Weston, CT (US);
Gregory J. Fredeman, Wappingers Falls, NY (US);
David M. Onsongo, Newburgh, NY (US);
David R. Hanson, Brewster, NY (US);
Dureseti Chidambarrao, Weston, CT (US);
Gregory J. Fredeman, Wappingers Falls, NY (US);
David M. Onsongo, Newburgh, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A circuit is provided which is operable to program an electrically alterable element, e.g., fuse or antifuse, to a programmed state and determine whether the electrically alterable element is in the programmed state or not. Such circuit includes a multiple conduction state field effect transistor ('multi-state FET') having at least one of a source or a drain coupled to the electrically alterable element to apply a current to the electrically alterable element. The multi-state FET has a first threshold voltage and a second threshold voltage, both being effective at the same time, the second threshold voltage being higher than the first threshold voltage. The gate is operable to control operation of the multi-state FET in multiple states including a) an essentially nonconductive state; b) a first or 'low' conductive state when a gate-source voltage exceeds the first threshold voltage, in which the multi-state FET is biased to conduct a relatively low magnitude current for determining the state of the fuse; and c) a second conductive state when the gate-source voltage exceeds the second threshold voltage, in which the multi-state FET is biased to conduct a relatively high magnitude programming current.