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:
Nov. 28, 1995
Filed:
Jan. 13, 1995
Kathryn E Gordon, Mountain View, CA (US);
Andrew K Chan, Palo Alto, CA (US);
QuickLogic Corporation, Santa Clara, CA (US);
Abstract
The invention allows programming an antifuse so as to reduce the antifuse resistance and the standard deviation of the resistance without increasing the programming current. This is achieved by passing current pulses of the opposite polarity through the antifuse. In some embodiments, the magnitude of the second pulse is lower than the magnitude of the first pulse. Further, if the antifuse is formed on a semiconductor substrate with one electrode on top of the other electrode and on top of the substrate, the current during the first pulse flows from the top electrode to the bottom electrode and not vice versa. A programming circuitry is provided that allows to program antifuses in a programmable circuit. A driver circuit is connected to each 'horizontal' channel and each 'vertical' channel. Each driver circuit is controlled by data in the driver circuit. The driver circuits are connected into shift registers so that all the data can be entered from one, two, three or four inputs. No decoding circuitry is necessary. Before programming, the drivers precharge all the channels to an intermediate voltage. During programming, the channels that are not directly connected to the antifuse being programmed are switched to high impedance. As a result, the power consumption is reduced and the programming proceeds faster.