Patents by Inventor Jayakannan Jayapalan
Jayakannan Jayapalan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 7973541Abstract: Techniques for estimating resistance and capacitance of metal interconnects are described. An apparatus may include an interconnect, a set of pads, a set of isolation circuits, and a test circuit. The set of pads may be coupled to the interconnect and used for simultaneously applying a current through the interconnect and measuring a voltage across the interconnect. The current and voltage may be used to estimate the resistance of the interconnect. The test circuit may charge and discharge the interconnect to estimate the capacitance of the interconnect. The isolation circuits may isolate the pads from the interconnect when the test circuit charges and discharges the interconnect. The apparatus may further include another interconnect, another set of pads, and another set of isolation circuits that may be coupled in a mirror manner. Resistance and/or capacitance mismatch between the two interconnects may be accurately estimated.Type: GrantFiled: December 6, 2007Date of Patent: July 5, 2011Assignee: QUALCOMM IncorporatedInventors: Jayakannan Jayapalan, David Bang, Yang Du
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Patent number: 7675372Abstract: A configurable ring oscillator is operated in a first configuration so that an oscillating signal passes from a first node to a second node through a first signal path. A first measurement of an operational characteristic is made. The ring oscillator is operated in a second configuration where an oscillating signal passes from the first node to the second node through a second signal path. A second measurement is made. The first and second measurements are used to determine a circuit simulator parameter. If the first path has little interconnect and the second path has substantial interconnect, then the effect on circuit operation due to interconnect loading can be isolated from the effects on circuit operation due to variations in transistor performance. If the first and second paths are laid out to be identical, then the first and second measurements are usable to determine a circuit simulator mismatch parameter.Type: GrantFiled: March 23, 2007Date of Patent: March 9, 2010Assignee: QUALCOMM IncorporatedInventors: David Bang, Jayakannan Jayapalan
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Publication number: 20090146681Abstract: Techniques for estimating resistance and capacitance of metal interconnects are described. An apparatus may include an interconnect, a set of pads, a set of isolation circuits, and a test circuit. The set of pads may be coupled to the interconnect and used for simultaneously applying a current through the interconnect and measuring a voltage across the interconnect. The current and voltage may be used to estimate the resistance of the interconnect. The test circuit may charge and discharge the interconnect to estimate the capacitance of the interconnect. The isolation circuits may isolate the pads from the interconnect when the test circuit charges and discharges the interconnect. The apparatus may further include another interconnect, another set of pads, and another set of isolation circuits that may be coupled in a mirror manner. Resistance and/or capacitance mismatch between the two interconnects may be accurately estimated.Type: ApplicationFiled: December 6, 2007Publication date: June 11, 2009Applicant: QUALCOMM IncorporatedInventors: Jayakannan Jayapalan, David Bang, Yang Du
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Publication number: 20080048790Abstract: A configurable ring oscillator is operated in a first configuration so that an oscillating signal passes from a first node to a second node through a first signal path. A first measurement of an operational characteristic is made. The ring oscillator is operated in a second configuration where an oscillating signal passes from the first node to the second node through a second signal path. A second measurement is made. The first and second measurements are used to determine a circuit simulator parameter. If the first path has little interconnect and the second path has substantial interconnect, then the effect on circuit operation due to interconnect loading can be isolated from the effects on circuit operation due to variations in transistor performance. If the first and second paths are laid out to be identical, then the first and second measurements are usable to determine a circuit simulator mismatch parameter.Type: ApplicationFiled: March 23, 2007Publication date: February 28, 2008Applicant: QUALCOMM INCORPORATEDInventors: David Bang, Jayakannan Jayapalan
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Patent number: 7281229Abstract: A method in accordance with the present invention prepares an alternate view of an integrated circuit (IC) layout from a top view thereof by selecting an initial polygon representing and IC feature from the top view of the layout, where the initial polygon is defined by a plurality of initial points. The coordinates the plurality of initial points are mapped onto coordinates of a plurality of translated points that define a second polygon representing an alternate view of the initial polygon. The mapping uses at least one of either the height of the initial polygon or the width of the initial polygon. The method can be used, for example and without limitation, to generate a three dimensional view from the top view of the layout or a sectional view of the layout.Type: GrantFiled: September 14, 2004Date of Patent: October 9, 2007Assignee: Altera CorporationInventor: Jayakannan Jayapalan
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Patent number: 7272884Abstract: The present invention is directed to an inductor fabricated above a substrate surface comprising a first set of inductors in a lower dielectric layer, a second set of inductors in an upper dielectric layer, and interconnects extending between the first and second sets of conductors to form a single continuous helical current path that turns around a central region. Since each turn of the inductor includes only one leg close to the substrate, the parasitic capacitance between the inductor and the substrate can be reduced and there is more free space in the upper and lower layers for increasing the width of the conductors and thereby reducing the series resistance of the inductor. Meanwhile, since the magnetic field generated by the inductor is substantially confined in a closed tube defined by its turns, there is less interference between the inductor and its neighboring components on the same and/or surrounding substrates.Type: GrantFiled: December 12, 2006Date of Patent: September 25, 2007Assignee: Altera CorporationInventors: Jayakannan Jayapalan, Shuxian Chen, Liping Li
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Patent number: 7235884Abstract: The present invention is a novel method whereby voids or solid opens at the bottom of via can be avoided without drastically altering the resistivity or parasitic capacitances of the whole metal interconnect system. The invention includes in one embodiment a process of forming interconnects and vias in a microelectronic circuit structure. This process includes implanting and/or alloying an impurity element in the local area of the top surface of a metal interconnect at the bottom of a via. Doping may be done before or after formation of the via. After the via is formed, it is filled with a metal such as copper. Another embodiment of the invention is a microelectronic circuit structure manufactured by the aforementioned method.Type: GrantFiled: April 1, 2003Date of Patent: June 26, 2007Assignee: Altera CorporationInventors: Peter John McElheny, Yow-Juang(Bill) W. Liu, Jayakannan Jayapalan, Francois Gregoire
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Publication number: 20070090914Abstract: The present invention is directed to an inductor fabricated above a substrate surface comprising a first set of inductors in a lower dielectric layer, a second set of inductors in an upper dielectric layer, and interconnects extending between the first and second sets of conductors to form a single continuous helical current path that turns around a central region. Since each turn of the inductor includes only one leg close to the substrate, the parasitic capacitance between the inductor and the substrate can be reduced and there is more free space in the upper and lower layers for increasing the width of the conductors and thereby reducing the series resistance of the inductor. Meanwhile, since the magnetic field generated by the inductor is substantially confined in a closed tube defined by its turns, there is less interference between the inductor and its neighboring components on the same and/or surrounding substrates.Type: ApplicationFiled: December 12, 2006Publication date: April 26, 2007Inventors: Jayakannan Jayapalan, Shuxian Chen, Liping Li
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Patent number: 7170382Abstract: The present invention is directed to an inductor fabricated above a substrate surface comprising a first set of inductors in a lower dielectric layer, a second set of inductors in an upper dielectric layer, and interconnects extending between the first and second sets of conductors to form a single continuous helical current path that turns around a central region. Since each turn of the inductor includes only one leg close to the substrate, the parasitic capacitance between the inductor and the substrate can be reduced and there is more free space in the upper and lower layers for increasing the width of the conductors and thereby reducing the series resistance of the inductor. Meanwhile, since the magnetic field generated by the inductor is substantially confined in a closed tube defined by its turns, there is less interference between the inductor and its neighboring components on the same and/or surrounding substrates.Type: GrantFiled: July 16, 2004Date of Patent: January 30, 2007Assignee: Altera CorporationInventors: Jayakannan Jayapalan, Shuxian Chen, Liping Li
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Patent number: 7067842Abstract: The present invention includes a method and apparatus for measuring a parasitic inductance associated with a portion of an integrated circuit fabricated on a semiconductor substrate. A test chip for measuring the parasitic inductance is fabricated together with the integrated circuit on the semiconductor substrate. The test chip includes an LC oscillator circuit having at least one substructure that resembles the portion of the integrated circuit and at least one varactor having a capacitance adjustable by a control voltage. When the LC oscillator circuit is connected to the control voltage source and the control voltage is at a certain level, an oscillation is generated in the LC oscillator and the frequency of oscillation can be used to determine the parasitic inductance associated with the portion of the integrated circuit.Type: GrantFiled: February 13, 2004Date of Patent: June 27, 2006Assignee: Altera CorporationInventors: Jayakannan Jayapalan, Liping Li, Yow-Juang Liu
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Patent number: 6829127Abstract: A capacitive electrode structure for use in an integrated circuit fabricated on a substrate comprises a first electrode formed by a diffusion region in the substrate, an insulating layer formed on the diffusion region, and a second electrode formed by a conductive layer deposited on said insulating layer. To increase the capacitance per chip area of the capacitive electrode structure, a plurality of recesses are formed in the first electrode on an upper surface thereof with a lower surface of the second electrode substantially following a contour of these recesses. In one embodiment, the capacitive electrode structure is employed for a capacitor formed between a control gate and a floating gate in an EEPROM cell. Capacitors in other types of integrated circuit can be likewise formed using the electrode structure of the present invention.Type: GrantFiled: March 5, 2003Date of Patent: December 7, 2004Assignee: Altera CorporationInventors: Yow-Juang (Bill) Liu, Jayakannan Jayapalan, Francois Gregoire, Peter John McElheny