Patents Assigned to SEQUENCE
  • Patent number: 7222318
    Abstract: A method is provided to optimize delay insertions for reducing timing violations. The method includes inserting a buffer between a driver and a receiver in a timing path and placing the buffer either inside or outside a bounding box that encloses the driver and the receiver. The placement of the buffer inside or outside the bounding box creates the appropriate effective loading on the buffer to generates the required minimum delay to avoid timing violations.
    Type: Grant
    Filed: July 25, 2003
    Date of Patent: May 22, 2007
    Assignee: Sequence Design, Inc.
    Inventor: Adi Srinivasan
  • Patent number: 7185300
    Abstract: A current waveform for an electronic circuit is calculated from a description of the circuit at a given level of abstraction without requiring a detailed simulation. In one embodiment, the waveform is estimated without using test vectors, and uses an analysis time step or “granularity” that is much shorter than a clock cycle. The method is applicable for calculating worst-case instantaneous current.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: February 27, 2007
    Assignee: Sequence Design, Inc.
    Inventor: Gerald L. Frenkil
  • Patent number: 7117457
    Abstract: This invention provides a mechanism for minimizing the switching time degradation of MTCMOS circuits while at the same time minimizing the area overhead due to the MTCMOS switch circuitry. This optimization is achieved by scheduling the current flow, due to the switching events of the MTCMOS logic cells, such that only temporally mutually exclusive currents, or currents whose cumulative sum is less than a predetermined value, can flow in any given switch cell. Techniques for current event merging and current event culling, and techniques for handling timing and current variances may be used.
    Type: Grant
    Filed: December 17, 2003
    Date of Patent: October 3, 2006
    Assignee: Sequence Design, Inc.
    Inventor: Gerald L. Frenkil
  • Patent number: 7081728
    Abstract: An induction motor system comprising an induction motor, equipped with a heat recovery and water pumping apparatus and an apparatus for controlling the electrical efficiency and resulting heat generation of the induction motor. The motor is adapted to be coupled to an AC source for supplying an AC signal. The controlling apparatus includes a switching device, user controls and optional inputs. The switching device is connected in series with the motor and is operative in either a high impedance state wherein significant current flow through the motor is prevented or a low impedance state wherein current flow through the motor is substantially undisturbed. The user controls provide motor operational input signals. The optional inputs provide setpoint and sensed water temperature input signals.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: July 25, 2006
    Assignee: Sequence Controls Inc.
    Inventor: William H. Kemp
  • Publication number: 20060043918
    Abstract: An induction motor system comprising an induction motor, equipped with a heat recovery and water pumping apparatus and an apparatus for controlling the electrical efficiency and resulting heat generation of the induction motor. The motor is adapted to be coupled to an AC source for supplying an AC signal. The controlling apparatus includes a switching device, user controls and optional inputs. The switching device is connected in series with the motor and is operative in either a high impedance state wherein significant current flow through the motor is prevented or a low impedance state wherein current flow through the motor is substantially undisturbed. The user controls provide motor operational input signals. The optional inputs provide setpoint and sensed water temperature input signals.
    Type: Application
    Filed: August 27, 2004
    Publication date: March 2, 2006
    Applicant: Sequence Controls Inc.
    Inventor: William Kemp
  • Patent number: 7003741
    Abstract: A method for optimal driver selection uses a cost function that is based on the non-linear delay characteristics and the stage gain of the candidate drivers. The cost function operates to select an optimal driver for driving the predetermined capacitive load which. simultaneously minimizes the delay and the amount of input capacitance introduced. In one embodiment, a method for selecting a driver for driving a load capacitance from a group of drivers includes: computing for each driver a cost based on a cost function associated with the driver, and selecting the driver having the smallest cost. The cost function is directly proportional to a delay of the driver and inversely proportional to the logarithm of a stage gain of the driver. In another embodiment, the stage gain is an output capacitance driven by the driver (the load capacitance) divided by an input capacitance of the driver.
    Type: Grant
    Filed: May 3, 2004
    Date of Patent: February 21, 2006
    Assignee: Sequence Design, Inc.
    Inventor: Adi Srinivasan
  • Patent number: 6901565
    Abstract: A system for analyzing the power consumption of a behavior description of an electrical design includes a structural element library including a set of technology-independent structural macro elements, a macro power model module providing macro power models for one or more of the structural macro elements in the structural element library, and a power estimation module providing a power consumption value of the electrical design using a netlist of interconnected components representative of the electrical design, and the macro power models. The macro power models are associated with corresponding power models in a user-specified gate-level power model library. The power analysis system enables behavior level or RTL power analysis using a user-specified gate-level cell power model library containing arc-based or pin-based power model descriptions or both.
    Type: Grant
    Filed: May 27, 2003
    Date of Patent: May 31, 2005
    Assignee: Sequence Design, Inc.
    Inventor: Serguei A. Sokolov
  • Patent number: 6847291
    Abstract: An apparatus operable in a wet environment for detecting the presence or absence of water in a non-conductive vessel, by measuring changes in dielectric constant and detecting the temperature of water in same vessel. A conductive element coupled to a sensing and switching means, transmits data to the controller, resulting from a change of dielectric constant at the conductive element. A temperature sensor detects and transmits temperature signals to the controller. A controller means receives data, from the dielectric constant sensor means and temperature data from the temperature sensor. Includes a coupling means which transmits data from the controller to an external device. The isolation means electrically isolates the conductive element and temperature sensor means from the water contained in a non-conductive vessel.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: January 25, 2005
    Assignee: Sequence Controls Inc.
    Inventor: William Harry Kemp
  • Patent number: 6807660
    Abstract: A current waveform for an electronic circuit is calculated from a description of the circuit at a given level of abstraction without requiring a detailed simulation. In one embodiment, the waveform is estimated without using test vectors, and uses an analysis time step or “granularity” that is much shorter than a clock cycle. The method is applicable for calculating worst-case instantaneous current.
    Type: Grant
    Filed: October 1, 2002
    Date of Patent: October 19, 2004
    Assignee: Sequence Design, Inc.
    Inventor: Gerald L. Frenkil
  • Patent number: 6754877
    Abstract: A method for optimal driver selection uses a cost function that is based on the non-linear delay characteristics and the stage gain of the candidate drivers. The cost function operates to select an optimal driver for driving the predetermined capacitive load which simultaneously minimizes the delay and the amount of input capacitance introduced. In one embodiment, a method for selecting a driver for driving a load capacitance from a group of drivers includes: computing for each driver a cost based on a cost function associated with the driver, and selecting the driver having the smallest cost. The cost function is directly proportional to a delay of the driver and inversely proportional to the logarithm of a stage gain of the driver. In another embodiment, the stage gain is an output capacitance driven by the driver (the load capacitance) divided by an input capacitance of the driver.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: June 22, 2004
    Assignee: Sequence Design, Inc.
    Inventor: Adi Srinivasan
  • Publication number: 20040088664
    Abstract: A method is provided to optimize delay insertions for reducing timing violations. The method includes inserting a buffer between a driver and a receiver in a timing path and placing the buffer either inside or outside a bounding box that encloses the driver and the receiver. The placement of the buffer inside or outside the bounding box creates the appropriate effective loading on the buffer to generates the required minimum delay to avoid timing violations.
    Type: Application
    Filed: July 25, 2003
    Publication date: May 6, 2004
    Applicant: Sequence Design, Inc.
    Inventor: Adi Srinivasan
  • Patent number: 6701507
    Abstract: A method for computing a position for a zero-skew driver insertion point in an area occupied by nodes driven by the driver is described. The zero-skew driver insertion point is the position in the area where the spread of the signal arrival times at the nodes driven by the driver is minimized. The method includes: expressing a function describing a distance from each of the nodes to the zero-skew driver insertion point, expressing the variance of the function, minimizing the variance of the function, and solving an equation representative of the minimization of the variance of the function to determine the position of the zero-skew driver insertion point. In one embodiment, the minimizing the variance of the function includes: taking a first derivative of the function with respect to the distance, and setting the first derivative of the function to zero.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: March 2, 2004
    Assignee: Sequence Design, Inc.
    Inventor: Adi Srinivasan
  • Patent number: 6701505
    Abstract: A method is provided to optimize delay insertions for reducing timing violations. The method includes inserting a buffer between a driver and a receiver in a timing path and placing the buffer either inside or outside a bounding box that encloses the driver and the receiver. The placement of the buffer inside or outside the bounding box creates the appropriate effective loading on the buffer to generates the required minimum delay to avoid timing violations.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: March 2, 2004
    Assignee: Sequence Design, Inc.
    Inventor: Adi Srinivasan
  • Patent number: 6701506
    Abstract: A method for “match-delay” buffer insertion is provided to add delays at a node without changing the input capacitance of the node as seen by the upstream node. In one embodiment, a method for inserting a delay in a node in an electrical design associated with a logic gate includes: adding the delay at the node by adding a new logic gate before the node where the new logic gate is the same cell type as the logic gate and is positioned near the logic gate. The method may further include: determining if the delay can be added by adding a new logic gate before the node, and if a new logic gate cannot be added before the node, adding the delay by adding a new logic gate after the logic gate where a combination of the logic gate and the new logic gate giving the delay to be added.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: March 2, 2004
    Assignee: Sequence Design, Inc.
    Inventors: Adi Srinivasan, David L. Allen
  • Patent number: 6698006
    Abstract: A clock tree insertion method for distributing a clock signal in an integrated circuit design includes providing a physical design representative of the integrated circuit design, specifying a location for a root node of the clock tree in the physical design, constructing an array of buffers as the clock tree where the array of buffers is constructed to minimize the maximum insertion delay from the root node to the clock signal endpoints and to meet a predefined maximum insertion delay constraint, identifying locations in the clock tree where clock skew violations occur and correcting the clock skew violations by introducing delay at buffer locations in the clock tree having the fastest clock signal arrival times, and identifying locations in the clock tree where minimum insertion delay violations occur and correcting the minimum insertion delay violations by slowing down the arrival times of clock signal endpoints of the clock tree.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: February 24, 2004
    Assignee: Sequence Design, Inc.
    Inventors: Adi Srinivasan, David L. Allen
  • Patent number: 6643831
    Abstract: A novel parasitic extraction system includes an interconnect primitive library that has a parameterized inductance function for at least one conducting layer of the integrated circuit. A parasitic extractor analyzes structures within a selected distance of a selected conductor within the integrated circuit and determines parasitic inductance values for the selected conductor using the parameterized inductance function of the interconnect primitive library. Using this parasitic extraction system, parasitic impedances, including inductance, may be extracted for an integrated circuit layout, thus allowing more accurate modeling and timing analysis of the integrated circuit layout to be obtained.
    Type: Grant
    Filed: January 24, 2002
    Date of Patent: November 4, 2003
    Assignee: Sequence Design, Inc.
    Inventors: Keh-Jeng Chang, Li-Fu Chang, Robert G. Mathews, Martin G. Walker
  • Publication number: 20030177455
    Abstract: A method and an apparatus are provided for post-layout optimization of an integrated circuit. In one instance, only local transformations accomplished by incremental changes to placement and routing are provided, so as to avoid the costly design iteration loop that requires re-synthesis, re-place and re-route. Optimization can be provided in multiple optimization phases each accomplishing a specified set of transformations. Static timing analysis is performed at the end of each set of local transformations to determine if further optimization steps are required. In one instance, the physical design is first scanned for mismatch between drivers and loads. Then, in a second optimization phase, “hot spots” in the physical design are identified for local transformation using a “bidirectional combinational total negative slack” (BCTNS) algorithm. In subsequent phases, optimization based on meeting setup times and hold times in a critical path are performed.
    Type: Application
    Filed: March 12, 2003
    Publication date: September 18, 2003
    Applicant: Sequence Design, Inc.
    Inventors: Douglas Kaufman, Hazem Almusa, Vinay Srinivas, Donald V. Organ, Larry Ke, Wei Li, Japinder Singh, Robert Mathews
  • Patent number: 6598209
    Abstract: A system for analyzing the power consumption of a behavior description of an electrical design includes a structural element library including a set of technology-independent structural macro elements, a macro power model module providing macro power models for one or more of the structural macro elements in the structural element library, and a power estimation module providing a power consumption value of the electrical design using a netlist of interconnected components representative of the electrical design, and the macro power models. The macro power models are associated with corresponding power models in a user-specified gate-level power model library. The power analysis system enables behavior level or RTL power analysis using a user-specified gate-level cell power model library containing arc-based or pin-based power model descriptions or both.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: July 22, 2003
    Assignee: Sequence Design, Inc.
    Inventor: Serguei A. Sokolov
  • Patent number: 6591407
    Abstract: A method and an apparatus are provided for post-layout optimization of an integrated circuit. In one instance, only local transformations accomplished by incremental changes to placement and routing are provided, so as to avoid the costly design iteration loop that requires re-synthesis, re-place and re-route. Optimization can be provided in multiple optimization phases each accomplishing a specified set of transformations. Static timing analysis is performed at the end of each set of local transformations to determine if further optimization steps are required. In one instance, the physical design is first scanned for mismatch between drivers and loads. Then, in a second optimization phase, “hot spots” in the physical design are identified for local transformation using a “bidirectional combinational total negative slack” (BCTNS) algorithm. In subsequent phases, optimization based on meeting setup times and hold times in a critical path are performed.
    Type: Grant
    Filed: March 1, 2000
    Date of Patent: July 8, 2003
    Assignee: Sequence Design, Inc.
    Inventors: Douglas Kaufman, Hazem Almusa, Vinay Srinivas, Donald V. Organ, Larry Ke, Wei Li, Japinder Singh, Robert Mathews
  • Patent number: 6574787
    Abstract: An embodiment of the present invention is a method for logic synthesis that reduces use of computer memory and reduces computer runtime. In particular, an embodiment of the present invention is a method for logic synthesis which includes the steps of: (a) analyzing an HDL model to develop a parse tree and (b) elaborating the parse tree to create a word-oriented netlist.
    Type: Grant
    Filed: August 16, 1999
    Date of Patent: June 3, 2003
    Assignee: Sequence Design, Inc.
    Inventor: Glen R. Anderson