Patents by Inventor Douglas Chang
Douglas Chang 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: 11694016Abstract: A method includes receiving a netlist for a chip including a bus and determining, by one or more processors and based on the netlist, a first routing topology for the bus and through a routing region of the chip by comparing a demand of the bus to a capacity of a plurality of cells of the routing region. The method also includes generating a layout for the chip based on the first routing topology.Type: GrantFiled: June 11, 2021Date of Patent: July 4, 2023Assignee: Synopsys, Inc.Inventors: Zhengtao Yu, Balkrishna Rashingkar, David Peart, Douglas Chang, Yiding Han
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Publication number: 20220411025Abstract: A floating power-generation group comprises a floating hub such as a spar buoy that is anchored to subsea foundations by anchor lines. Floating power producer units such as wind turbines are connected electrically and mechanically to the hub. The power producer units are each moored by mooring lines. At least one mooring line extends inwardly toward the hub to effect mechanical connection to the hub and at least one other mooring line extends outwardly toward a subsea foundation. The groups are combined as a set whose hubs are connected electrically to each other via subsea energy storage units. Anchor lines of different groups can share subsea foundations. The storage units comprise pumping machinery to expel water from an elongate storage volume and generating machinery to generate electricity from a flow of water entering the storage volume. The pumping machinery may be in deeper water than the generating machinery.Type: ApplicationFiled: October 22, 2020Publication date: December 29, 2022Inventors: Paul Douglas Chang, Ernst Kristen Helgoy Kloster
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Publication number: 20220300687Abstract: A system determines physical design information along a logic hierarchy of a circuit design. The system accesses physical design metrics associated with different parts of a physical design of a circuit. The system accesses a logic design of the circuit comprising a hierarchy of logic blocks. The system determines the physical design metrics associated with one or more logic blocks of the hierarchy of the logic design based on a relation between the physical design and the logic design. The system configures a user interface to display the hierarchy of the logic design of the circuit along with the physical design metrics associated with the one or more logic blocks of the hierarchy. The system sends the configured user interface for display.Type: ApplicationFiled: March 15, 2022Publication date: September 22, 2022Inventors: Amit Jalota, Andrew Saunders, Aruna Kanagaraj, Douglas Chang, Eshwari Rajendran, Prashant Gupta, Rajeev Murgai, Soumitra Majumder, Vasiliki Chatzi, Balkrishna Ramchandra Rashingkar
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Publication number: 20210390241Abstract: A method includes receiving a netlist for a chip including a bus and determining, by one or more processors and based on the netlist, a first routing topology for the bus and through a routing region of the chip by comparing a demand of the bus to a capacity of a plurality of cells of the routing region. The method also includes generating a layout for the chip based on the first routing topology.Type: ApplicationFiled: June 11, 2021Publication date: December 16, 2021Inventors: Zhengtao YU, Balkrishna RASHINGKAR, David PEART, Douglas CHANG, Yiding HAN
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Patent number: 10318692Abstract: Some embodiments can receive a netlist for the circuit design, wherein the netlist is divided into a set of blocks and a top-level netlist. Next, the embodiments can create (1) a top-level netlist abstraction based on the top-level netlist, and (2) for each block in the set of blocks, create a block abstraction based on a portion of the netlist that is in the block and create virtual pin cells in the block, wherein each virtual pin cell corresponds to a connection that crosses a boundary of the block. The embodiments can then place the top-level netlist abstraction in the layout area, the set of blocks in the layout area, the block abstractions in corresponding blocks, and the virtual pin cells in corresponding blocks. The placed circuit abstraction can then be used to drive standard cell placement in the circuit design.Type: GrantFiled: March 23, 2015Date of Patent: June 11, 2019Assignee: SYNOPSYS, INC.Inventors: Douglas Chang, Balkrishna R. Rashingkar
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Publication number: 20160283632Abstract: Some embodiments can receive a netlist for the circuit design, wherein the netlist is divided into a set of blocks and a top-level netlist. Next, the embodiments can create (1) a top-level netlist abstraction based on the top-level netlist, and (2) for each block in the set of blocks, create a block abstraction based on a portion of the netlist that is in the block and create virtual pin cells in the block, wherein each virtual pin cell corresponds to a connection that crosses a boundary of the block. The embodiments can then place the top-level netlist abstraction in the layout area, the set of blocks in the layout area, the block abstractions in corresponding blocks, and the virtual pin cells in corresponding blocks. The placed circuit abstraction can then be used to drive standard cell placement in the circuit design.Type: ApplicationFiled: March 23, 2015Publication date: September 29, 2016Applicant: SYNOPSYS, INC.Inventors: Douglas Chang, Balkrishna R. Rashingkar
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Patent number: 9026974Abstract: Methods and apparatuses are described for facilitating a user to explore and evaluate different options during floorplanning. Some embodiments display a graphical representation of a circuit design floorplan, wherein the graphical representation includes a set of blocks and a set of flylines between blocks, wherein each block corresponds to a portion of the circuit design, and wherein each flyline corresponds to one or more relationships between two blocks. Additionally, a set of metrics associated with one or more blocks or one or more flylines can be displayed. Next, in response to receiving a modification to one or more blocks in the graphical representation, the embodiments can update the set of metrics without performing expensive netlist modification, placement, routing, and/or propagation of timing information through multiple levels of logic, and then display the updated set of metrics.Type: GrantFiled: December 24, 2013Date of Patent: May 5, 2015Assignee: Synopsys, Inc.Inventors: Russell B. Segal, Balkrishna R. Rashingkar, Douglas Chang, Mattias A. Hembruch
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Patent number: 8910097Abstract: Systems and techniques for creating a netlist abstraction are described. During operation, an embodiment can receive a netlist for a circuit design, wherein circuit elements in the circuit design are organized in a logical hierarchy (LH). Next, the embodiment can receive a set of LH nodes in the LH. The embodiment can then create the netlist abstraction by, for each LH node in the set of LH nodes, replacing a portion of the netlist that is below the LH node by a star netlist, wherein the star netlist includes a center object that is electrically connected to a set of satellite objects, wherein each satellite object corresponds to a port of the LH node.Type: GrantFiled: March 22, 2013Date of Patent: December 9, 2014Assignee: Synopsys, Inc.Inventors: Douglas Chang, Balkrishna R. Rashingkar
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Patent number: 8893073Abstract: Methods and apparatuses are described for creating, editing, and viewing a floorplan of a circuit design. Specifically, some embodiments enable a user to perform a graphical operation at an inference point in a circuit design layout, wherein the location of the inference point is determined based on existing graphical objects in the circuit design layout. Some embodiments substantially instantaneously update a congestion indicator in a circuit design layout in response to modifying the circuit design layout. Some embodiments substantially instantaneously update pin locations of a block or partition in response to changing the size or shape of the block or partition. Some embodiments enable a user to view a circuit design layout based on the logical hierarchy, and also based on at least one additional attribute type such as voltage, power, or clock domain.Type: GrantFiled: December 27, 2012Date of Patent: November 18, 2014Assignee: Synopsys, Inc.Inventors: Balkrishna R. Rashingkar, David L. Peart, Russell Segal, Douglas Chang, Ksenia Roze
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Publication number: 20140189617Abstract: Methods and apparatuses are described for creating, editing, and viewing a floorplan of a circuit design. Specifically, some embodiments enable a user to perform a graphical operation at an inference point in a circuit design layout, wherein the location of the inference point is determined based on existing graphical objects in the circuit design layout. Some embodiments substantially instantaneously update a congestion indicator in a circuit design layout in response to modifying the circuit design layout. Some embodiments substantially instantaneously update pin locations of a block or partition in response to changing the size or shape of the block or partition. Some embodiments enable a user to view a circuit design layout based on the logical hierarchy, and also based on at least one additional attribute type such as voltage, power, or clock domain.Type: ApplicationFiled: December 27, 2012Publication date: July 3, 2014Applicant: SYNOPSYS, INC.Inventors: Balkrishna R. Rashingkar, David L. Peart, Russell Segal, Douglas Chang, Ksenia Roze
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Publication number: 20140189620Abstract: Systems and techniques for creating a netlist abstraction are described. During operation, an embodiment can receive a netlist for a circuit design, wherein circuit elements in the circuit design are organized in a logical hierarchy (LH). Next, the embodiment can receive a set of LH nodes in the LH. The embodiment can then create the netlist abstraction by, for each LH node in the set of LH nodes, replacing a portion of the netlist that is below the LH node by a star netlist, wherein the star netlist includes a center object that is electrically connected to a set of satellite objects, wherein each satellite object corresponds to a port of the LH node.Type: ApplicationFiled: March 22, 2013Publication date: July 3, 2014Applicant: Synopsys, Inc.Inventors: Douglas Chang, Balkrishna R. Rashingkar
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Publication number: 20140181776Abstract: Methods and apparatuses are described for facilitating a user to explore and evaluate different options during floorplanning. Some embodiments display a graphical representation of a circuit design floorplan, wherein the graphical representation includes a set of blocks and a set of flylines between blocks, wherein each block corresponds to a portion of the circuit design, and wherein each flyline corresponds to one or more relationships between two blocks. Additionally, a set of metrics associated with one or more blocks or one or more flylines can be displayed. Next, in response to receiving a modification to one or more blocks in the graphical representation, the embodiments can update the set of metrics without performing expensive netlist modification, placement, routing, and/or propagation of timing information through multiple levels of logic, and then display the updated set of metrics.Type: ApplicationFiled: December 24, 2013Publication date: June 26, 2014Applicant: Synopsys, Inc.Inventors: Russell B. Segal, Balkrishna R. Rashingkar, Douglas Chang, Mattias A. Hembruch
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Patent number: 8037442Abstract: One embodiment of the present invention provides a system that scales an I/O-cell placement during die-size optimization. During operation, the system starts by receiving an initial die-size for a die and an initial I/O-cell placement for a set of I/O cells. The system also receives a target die-size for the die. The system then determines die-size changes between the initial die-size and the target die-size. Next, the system identifies available spaces between the set of I/O cells in the initial I/O-cell placement. The system subsequently scales the initial I/O-cell placement based on the identified available spaces and the die-size changes to obtain a new I/O-cell placement which fits in the target die-size.Type: GrantFiled: November 26, 2008Date of Patent: October 11, 2011Assignee: Synopsys, Inc.Inventors: Peiqing Zou, Douglas Chang, Neeraj Kaul
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Patent number: 8001514Abstract: One embodiment of the present invention provides a system that computes a routability estimation across a collection of local routing regions associated with a circuit layout. This system first selects a first local routing region associated with a route overflow, wherein a respective local routing region is associated with an estimation of a number of route overflows for routing layers in a region of the circuit layout. Furthermore, a respective routing layer is associated with a preferred direction variable D. Next, the system transfers an overflow value k in direction d away from an overflowing routing layer for the first local routing region to a second local routing region, which has the capacity to handle an overflow of k or more routes in a direction d. Finally, the system computes a global routability estimation as a function of a global overflow cost and an adjacent overflow cost.Type: GrantFiled: April 23, 2008Date of Patent: August 16, 2011Assignee: Synopsys, Inc.Inventors: Douglas Chang, Neeraj Kaul, Balkrishna Rashingkar
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Publication number: 20100131913Abstract: One embodiment of the present invention provides a system that scales an I/O-cell placement during die-size optimization. During operation, the system starts by receiving an initial die-size for a die and an initial I/O-cell placement for a set of I/O cells. The system also receives a target die-size for the die. The system then determines die-size changes between the initial die-size and the target die-size. Next, the system identifies available spaces between the set of I/O cells in the initial I/O-cell placement. The system subsequently scales the initial I/O-cell placement based on the identified available spaces and the die-size changes to obtain a new I/O-cell placement which fits in the target die-size.Type: ApplicationFiled: November 26, 2008Publication date: May 27, 2010Applicant: SYNOPSYS, INC.Inventors: Peiqing Zou, Douglas Chang, Neeraj Kaul
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Publication number: 20090271754Abstract: One embodiment of the present invention provides a system that computes a routability estimation across a collection of local routing regions associated with a circuit layout. This system first selects a first local routing region associated with a route overflow, wherein a respective local routing region is associated with an estimation of a number of route overflows for routing layers in a region of the circuit layout. Furthermore, a respective routing layer is associated with a preferred direction variable D. Next, the system transfers an overflow value k in direction d away from an overflowing routing layer for the first local routing region to a second local routing region, which has the capacity to handle an overflow of k or more routes in a direction d. Finally, the system computes a global routability estimation as a function of a global overflow cost and an adjacent overflow cost.Type: ApplicationFiled: April 23, 2008Publication date: October 29, 2009Applicant: SYNOPSYS, INC.Inventors: Douglas Chang, Neeraj Kaul, Balkrishna Rashingkar
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Patent number: 6285355Abstract: A mouse-associated Z-axis encoder mainly including a rotary-shaft mount, an encoding disc, and an encoding wheel, and being mounted in a mouse at a position corresponding to a mid-key of the mouse. The rotary-shaft mount has a connection seat provided to an upper portion thereof. A rotary shaft and a plurality of cylindrical sleeves are axially provided on the connection seat. Each of the cylindrical sleeves has a contact finger and an elastic element mounted therein. At least one of the contact fingers is connected to electric signals. The encoding disc is disposed in the encoding wheel so that they are together mounted around the rotary shaft. The encoding wheel is partially protruded from the mouse via the position for the mid-key. There are several series of connected or non-connected conductive contacting areas provided on the surface of the encoding disc.Type: GrantFiled: May 26, 1999Date of Patent: September 4, 2001Assignee: Key Mouse Electronic Enterprise Co.Inventor: Douglas Chang
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Patent number: 5345253Abstract: A track ball base structure comprises a single-piece body having a housing being composed of a plurality of standing plates in the top of the body with extruding portions in the upper end of which to get secure connection to a cover, a central circular recess with an opening bottom to hold a ball therein, a plurality of ball bearing holes evenly distributed around the upper rim of the circular panel in the housing with an inner rectangular plate inside the uppermost of each hole for admitting ball bearings therein and at the same time holding them in place, multiple pairs of locking means and slots in both sides of the body for locking the detecting system as well as fixing the body substantially onto an integrated circuit plate. The present invention is characterized by providing a track ball base structure in a non-assembly manner. Therefore, the number of component parts required for the track ball is reduced and clearly any damage occurring under interconnection for each part can be eliminated.Type: GrantFiled: January 21, 1994Date of Patent: September 6, 1994Assignee: Behavior Tech Computer Corp.Inventor: Douglas Chang