Patents by Inventor Deepak Sabharwal

Deepak Sabharwal 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).

  • Patent number: 8546251
    Abstract: A method of manufacturing a read only memory cell includes connecting electrically a drain of the transistor to the bit line with a first conductor and a via. The method also includes generating a logic zero at a source of the transistor by electrically connecting the source of the transistor to a ground line with the first conductor. Further, the method includes, programming the read only memory cell to logic zero. A method of manufacturing a read only memory cell includes connecting electrically a drain of the transistor to the bit line with a first conductor and a via. The method also includes, connecting electrically a source of the transistor to the drain with the first conductor. Further, the method includes programming the read only memory cell to logic one.
    Type: Grant
    Filed: December 31, 2008
    Date of Patent: October 1, 2013
    Assignee: Synopsys, Inc.
    Inventors: Vineet Kumar Sachan, Amit Khanuja, Deepak Sabharwal
  • Patent number: 8031541
    Abstract: Read only memory (ROM) with minimum leakage is provided. The ROM includes a read only memory array. The read only memory array includes a first transistor, wherein a drain, a source, a gate, and a bulk of the first transistor is electrically connected to a logic zero in the idle state for ensuring zero junction and sub-threshold leakage current. Another ROM includes a first transistor comprising a gate, electrically connected to a word line to provide a read signal, a drain, electrically connected to a main bit line through a second transistor. The second transistor includes a gate, electrically connected to a first decoding circuit, a drain, electrically connected to the main bit line. A first reference bit line is electrically connected to a drain of a third transistor, wherein gate of the third transistor is electrically connected to a second decoding circuit for generating a stop read signal.
    Type: Grant
    Filed: December 31, 2008
    Date of Patent: October 4, 2011
    Assignee: Synopsys, Inc.
    Inventors: Vineet Kumar Sachan, Amit Khanuja, Deepak Sabharwal
  • Patent number: 8031542
    Abstract: A Read only memory (ROM) with minimum leakage includes a ROM array including a first transistor, wherein a drain, a source, a gate, and a bulk of the first transistor is electrically connected to a logic zero in the idle state for ensuring zero junction and sub-threshold leakage current. The drain of the first transistor is electrically connected to a main bit line through a second transistor. The second transistor includes a gate, electrically connected to a first decoding circuit, a drain, electrically connected to the main bit line. A first reference bit line is electrically connected to a drain of a third transistor, wherein gate of the third transistor is electrically connected to a second decoding circuit for generating a stop read signal. A second reference bit line, electrically connected to the first decoding circuit through a first sensing unit for generating a stop pre-charge signal.
    Type: Grant
    Filed: September 28, 2010
    Date of Patent: October 4, 2011
    Assignee: Synopsys, Inc.
    Inventors: Vineet Kumar Sachan, Deepak Sabharwal, Amit Khanuja
  • Patent number: 7940550
    Abstract: A source-biasing mechanism for leakage reduction in SRAM in which SRAM cells are arranged into a plurality of sectors. In standby mode, the SRAM cells in a sector in the plurality of sectors are deselected and a source-biasing potential is provided to the SRAM cells of the plurality sectors. In working mode, the source-biasing potential provided to the SRAM cells of a selected sector in the plurality of sectors is deactivated and the SRAM cells in a physical row within the selected sector are read while the remaining SRAM cells in the unselected sectors continue to be source-biased. The source-biasing potential provided to the SRAM cells that are in standby mode can be set to different voltages based on the logical state of control signals.
    Type: Grant
    Filed: September 14, 2009
    Date of Patent: May 10, 2011
    Assignee: Synopsys, Inc.
    Inventors: Niranjan Behera, Deepak Sabharwal, Yong Zhang
  • Patent number: 7929347
    Abstract: A compact, shared source line and bit line architecture for a diffusion programmable ROM. In one embodiment, a ROM circuit or instance includes a plurality of storage cells organized as an array of rows columns. A shared source line is associated with a first pair of adjacent columns, the shared source line being maintained at a predetermined level, wherein source terminals of storage cells in the adjacent columns are electrically coupled to the shared source line. A shared bit line is associated with a second pair of adjacent columns, the shared bit line being maintained at the predetermined level, wherein drain terminals of storage cells in the adjacent columns are electrically coupled to the shared bit line.
    Type: Grant
    Filed: October 12, 2009
    Date of Patent: April 19, 2011
    Assignee: Synopsys, Inc.
    Inventors: Amit Khanuja, Deepak Sabharwal
  • Publication number: 20110063893
    Abstract: A source-biasing mechanism for leakage reduction in SRAM in which SRAM cells are arranged into a plurality of sectors. In standby mode, the SRAM cells in a sector in the plurality of sectors are deselected and a source-biasing potential is provided to the SRAM cells of the plurality sectors. In working mode, the source-biasing potential provided to the SRAM cells of a selected sector in the plurality of sectors is deactivated and the SRAM cells in a physical row within the selected sector are read while the remaining SRAM cells in the unselected sectors continue to be source-biased. The source-biasing potential provided to the SRAM cells that are in standby mode can be set to different voltages based on the logical state of control signals.
    Type: Application
    Filed: September 14, 2009
    Publication date: March 17, 2011
    Inventors: Niranjan Behera, Deepak Sabharwal, Yong Zhang
  • Publication number: 20110013444
    Abstract: A Read only memory (ROM) with minimum leakage includes a ROM array including a first transistor, wherein a drain, a source, a gate, and a bulk of the first transistor is electrically connected to a logic zero in the idle state for ensuring zero junction and sub-threshold leakage current. The drain of the first transistor is electrically connected to a main bit line through a second transistor. The second transistor includes a gate, electrically connected to a first decoding circuit, a drain, electrically connected to the main bit line. A first reference bit line is electrically connected to a drain of a third transistor, wherein gate of the third transistor is electrically connected to a second decoding circuit for generating a stop read signal. A second reference bit line, electrically connected to the first decoding circuit through a first sensing unit for generating a stop pre-charge signal.
    Type: Application
    Filed: September 28, 2010
    Publication date: January 20, 2011
    Applicant: Virage Logic Corporation
    Inventors: Vineet Kumar SACHAN, Deepak Sabharwal, Amit Khanuja
  • Patent number: 7692964
    Abstract: A Static Random Access Memory (SRAM) cell having a source-biasing mechanism for leakage reduction. In standby mode, the cell's wordline is deselected and a source-biasing potential is provided to the cell. In read mode, the wordline is selected and responsive thereto, the source-biasing potential provided to the cell is deactivated. Upon completion of reading, the source-biasing potential is re-activated.
    Type: Grant
    Filed: June 12, 2006
    Date of Patent: April 6, 2010
    Assignee: Virage Logic Corp.
    Inventors: Deepak Sabharwal, Alexander Shubat
  • Publication number: 20100027312
    Abstract: A compact, shared source line and bit line architecture for a diffusion programmable ROM. In one embodiment, a ROM circuit or instance includes a plurality of storage cells organized as an array of rows columns. A shared source line is associated with a first pair of adjacent columns, the shared source line being maintained at a predetermined level, wherein source terminals of storage cells in the adjacent columns are electrically coupled to the shared source line. A shared bit line is associated with a second pair of adjacent columns, the shared bit line being maintained at the predetermined level, wherein drain terminals of storage cells in the adjacent columns are electrically coupled to the shared bit line.
    Type: Application
    Filed: October 12, 2009
    Publication date: February 4, 2010
    Applicant: VIRAGE LOGIC CORP.
    Inventors: Amit Khanuja, Deepak Sabharwal
  • Patent number: 7609550
    Abstract: A compact, shared source line and bit line architecture for a diffusion programmable ROM. In one embodiment, a ROM circuit or instance includes a plurality of storage cells organized as an array of rows columns. A shared source line is associated with a first pair of adjacent columns, the shared source line being maintained at a predetermined level, wherein source terminals of storage cells in the adjacent columns are electrically coupled to the shared source line. A shared bit line is associated with a second pair of adjacent columns, the shared bit line being maintained at the predetermined level, wherein drain terminals of storage cells in the adjacent columns are electrically coupled to the shared bit line.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: October 27, 2009
    Assignee: Virage Logic Corp.
    Inventors: Amit Khanuja, Deepak Sabharwal
  • Publication number: 20080212355
    Abstract: A compact, shared source line and bit line architecture for a diffusion programmable ROM. In one embodiment, a ROM circuit or instance includes a plurality of storage cells organized as an array of rows columns. A shared source line is associated with a first pair of adjacent columns, the shared source line being maintained at a predetermined level, wherein source terminals of storage cells in the adjacent columns are electrically coupled to the shared source line. A shared bit line is associated with a second pair of adjacent columns, the shared bit line being maintained at the predetermined level, wherein drain terminals of storage cells in the adjacent columns are electrically coupled to the shared bit line.
    Type: Application
    Filed: April 8, 2008
    Publication date: September 4, 2008
    Applicant: VIRAGE LOGIC CORP.
    Inventors: Amit Khanuja, Deepak Sabharwal
  • Patent number: 7376013
    Abstract: A compact, shared source line and bit line architecture for a diffusion programmable ROM. In one embodiment, a ROM circuit or instance includes a plurality of storage cells organized as an array having M rows and N columns. A shared source line is associated with each pair of adjacent columns, the shared source line being maintained at a predetermined level, wherein source terminals of storage cells in the adjacent columns are electrically coupled to the shared source line. Likewise, a shared bit line is associated with each pair of adjacent columns, except with respect to the edge columns of the array, the shared bit line being maintained at the predetermined level, wherein drain terminals of storage cells in the adjacent columns are electrically coupled to the shared bit line.
    Type: Grant
    Filed: March 21, 2006
    Date of Patent: May 20, 2008
    Assignee: Virage Logic Corp.
    Inventors: Amit Khanuja, Deepak Sabharwal
  • Patent number: 7298659
    Abstract: A method and system for testing the individual memory cells of a volatile memory cell array (e.g., SRAM) for data retention faults are described. In one embodiment of the invention, adjacent memory cells connected by a pair of common bit-lines are written with opposite, or complementary, data, for example, logical “0” and logical “1”. Next, the two memory cells are subjected to a stress condition by pre-charging the common bit-lines connecting the two adjacent memory cells, and then simultaneously asserting the word-line of each memory cell. Finally, the data in each cell is read and compared with the data written to the cell prior to generating the stress condition.
    Type: Grant
    Filed: June 7, 2005
    Date of Patent: November 20, 2007
    Assignee: Virage Logic Corporation
    Inventors: Subramani Kengeri, Deepak Sabharwal, Prakash Bhatia, Sanjiv Kainth
  • Patent number: 7251186
    Abstract: A multi-port memory device with an array of single-port memory cells is disclosed. According to one embodiment of the invention, the multi-port memory device has N number of memory ports, and is capable of performing any combination of N number of read/write operations during a single cycle of an externally generated core clock signal, without the need of any other externally generated clocking signals.
    Type: Grant
    Filed: June 7, 2005
    Date of Patent: July 31, 2007
    Assignee: Virage Logic Corporation
    Inventors: Subramani Kengeri, Deepak Sabharwal, Prakash Bhatia, Shreekanth Sampigethaya, Sanjiv Kainth
  • Publication number: 20070070698
    Abstract: A compact, shared source line and bit line architecture for a diffusion programmable ROM. In one embodiment, a ROM circuit or instance includes a plurality of storage cells organized as an array having M rows and N columns. A shared source line is associated with each pair of adjacent columns, the shared source line being maintained at a predetermined level, wherein source terminals of storage cells in the adjacent columns are electrically coupled to the shared source line. Likewise, a shared bit line is associated with each pair of adjacent columns, except with respect to the edge columns of the array, the shared bit line being maintained at the predetermined level, wherein drain terminals of storage cells in the adjacent columns are electrically coupled to the shared bit line.
    Type: Application
    Filed: March 21, 2006
    Publication date: March 29, 2007
    Inventors: Amit Khanuja, Deepak Sabharwal
  • Patent number: 7197438
    Abstract: A memory compiler characterization system and method for determining parametric data, wherein memory compilers of a first type are rigorously characterized and memory compilers of a second type are sparsely characterized with respect to a particular parameter. Absolute scale factors are determined based on the ratio of the parametric data points of two congruent memory compilers, one from each type. Interpolated scale factors are obtained based on the absolute scale factors. Parametric data for the remaining compilers of the sparsely characterized compiler set is filled out by applying the interpolated scale factors in conjunction with the data of the congruent memory compilers of the first type.
    Type: Grant
    Filed: October 18, 2001
    Date of Patent: March 27, 2007
    Assignee: Virage Logic Corp.
    Inventors: Deepak Mehta, Andrew Knight, Deepak Sabharwal, Raymond Tak-Hoi
  • Patent number: 7061794
    Abstract: A source-biasing mechanism for leakage reduction in SRAM. In standby mode, wordlines are deselected and a source-biasing potential is provided to SRAM cells. In read mode, a selected wordline deactivates the source-biasing potential provided to the selected row of SRAM cells, whereas the remaining SRAM cells on the selected bitline column continue to be source-biased.
    Type: Grant
    Filed: March 30, 2004
    Date of Patent: June 13, 2006
    Assignee: Virage Logic Corp.
    Inventors: Deepak Sabharwal, Alexander Shubat
  • Patent number: 7002827
    Abstract: Methods and apparatuses in which a ROM memory array has virtual-grounded source lines programmed in layer physically higher than the diffusion layer. The ROM memory array may include a diffusion layer, one or more virtual-grounded source lines, and one or more bit lines. At least one of the virtual-grounded source lines is programmed with a layer physically higher than the diffusion layer.
    Type: Grant
    Filed: February 10, 2003
    Date of Patent: February 21, 2006
    Assignee: Virage Logic Corporation
    Inventors: Deepak Sabharwal, Izak Kense, Alexander Shubat
  • Patent number: 6853572
    Abstract: Various methods, apparatuses, and systems in which a read only memory is arrayed in a multiple rows and columns. A first column of memory cells is organized into groups of memory cells including a first group of memory cells and a second group of memory cells. A first source line connects to one or more memory cells in the first group of memory cells. The first source line changes its voltage state during a read operation on one or more bit cells in the first group. A second source line connects to one or more memory cells in the second group of memory cells. The second source line maintains its voltage state during the read operation.
    Type: Grant
    Filed: February 28, 2003
    Date of Patent: February 8, 2005
    Assignee: Virage Logic Corporation
    Inventor: Deepak Sabharwal
  • Patent number: 6738953
    Abstract: A memory characterization system and method using a hierarchically-stitched netlist generation technique. A plurality of leaf cells forming a memory instance are generated based on a minimum area required to encompass an optimal number of memory strap points relating to global signals that span the memory instance. Input and output pins are defined for each tile with respect to the global signals in both horizontal and vertical directions. A parametric dataset is obtained for each tile using an extractor (wherein the memory instance is in post-layout condition) or a pre-layout wire-delay estimator. The parametric netlist for the entire memory instance is assembled by coupling the individual parametric datasets using the input and output pins of the tiles with respect to the global signals.
    Type: Grant
    Filed: March 5, 2002
    Date of Patent: May 18, 2004
    Assignee: Virage Logic Corp.
    Inventors: Deepak Sabharwal, Alex Shubat