Patents by Inventor Irfan Rahim

Irfan Rahim 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).

  • Publication number: 20070096152
    Abstract: A lateral bipolar transistor comprises an emitter region, a base region, a collector region, and a gate disposed over the base region. A bias line is connected to the gate for applying a bias voltage thereto during operation of the transistor. The polarity of the bias voltage is such as to create an accumulation layer in the base under the gate. The accumulation layer provides a low-resistance path for the transistor base current, thus reducing the base resistance of the transistor.
    Type: Application
    Filed: December 13, 2006
    Publication date: May 3, 2007
    Inventor: Irfan Rahim
  • Patent number: 7210115
    Abstract: Methods and apparatus for designing and producing programmable logic devices are provided. A logic design system may be used to analyze various implementations of a desired logic design for a programmable logic device integrated circuit. The logic design system may be used to produce configuration data for the programmable logic device in accordance with an optimized implementation. A logic circuit for a programmable logic device can be analyzed by taking into account the effects of hotspots, power supply voltage drops, and signal congestion on device performance. By modeling the performance of transistors and other components using position-dependent and signal-dependent variables such as temperature, voltage, and capacitance, the effects of congestion on device performance can be characterized and an optimum implementation of the logic design in a programmable logic device can be obtained.
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: April 24, 2007
    Assignee: Altera Corporation
    Inventors: Irfan Rahim, Yow-Juang (Bill) Liu
  • Publication number: 20070085558
    Abstract: The present invention optimizes the performance of integrated circuits by adjusting the circuit operating voltage using feedback on process/product parameters. To determine a desired value for the operating voltage of an integrated circuit, a preferred embodiment provides for on-wafer probing of one or more reference circuit structures to measure at least one electrical or operational parameter of the one or more reference circuit structures; determining an adjusted value for the operating voltage based on the measured parameter; and establishing the adjusted value as the desired value for the operating voltage. The reference circuit structures may comprise process control monitor structures or structures in other integrated circuits fabricated in the same production run.
    Type: Application
    Filed: December 13, 2006
    Publication date: April 19, 2007
    Inventors: Irfan Rahim, Peter McElheny, John Costello
  • Patent number: 7200824
    Abstract: Methods and apparatus are provided for harnessing the effects of process variations in a semiconductor device. In one example, implementing an electronic design based on collected performance parameters is provided. In general, a core is segmented into multiple core regions. A performance parameter can be collected from each of the core regions. The performance parameter can be collected with a performance measuring mechanism associated with the core region. The performance parameter can be correlated to the performance requirements of an electronic device portion, and the electronic design portion can be implemented in a core region that has a performance parameter matched to the needs of the electronic design portion. In this way, process variation effects are harnessed by optimizing the implementation of the electronic design in regions of the semiconductor device best suited the needs of each electronic design portion. Therefore, performance/power optimization of the semiconductor device can be realized.
    Type: Grant
    Filed: November 16, 2004
    Date of Patent: April 3, 2007
    Assignee: Altera Corporation
    Inventors: Lakhbeer Sidhu, Irfan Rahim
  • Publication number: 20070069764
    Abstract: A programmable logic device (PLD) includes a delay circuit and a body-bias generator. The delay circuit has a delay configured to represent a delay of user circuit implement in the PLD. The body-bias generator is configured to adjust the body bias of a transistor within the user circuit. The body-bias generator adjusts the body bias of the transistor in response to a level derived from the signal propagation delay of the delay circuit.
    Type: Application
    Filed: September 26, 2006
    Publication date: March 29, 2007
    Inventors: David Lewis, Vaughn Betz, Irfan Rahim, Peter McElheny, Yow-Juang Liu, Bruce Pedersen
  • Patent number: 7183800
    Abstract: Apparatus and methods are disclosed for improving the performance of a programmable logic device (PLD). A PLD includes a memory cell configured to provide a pair of voltages to a gate of a pass transistor and a body of the pass transistor, respectively.
    Type: Grant
    Filed: December 14, 2005
    Date of Patent: February 27, 2007
    Assignee: Altera Corporation
    Inventors: Irfan Rahim, Jeffrey T. Watt
  • Patent number: 7173320
    Abstract: A lateral bipolar transistor includes an emitter region, a base region, a collector region, and a gate disposed over the base region. A bias line is connected to the gate for applying a bias voltage thereto during operation of the transistor. The polarity of the bias voltage is such as to create an accumulation layer in the base under the gate. The accumulation layer provides a low-resistance path for the transistor base current, thus reducing the base resistance of the transistor.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: February 6, 2007
    Assignee: Altera Corporation
    Inventor: Irfan Rahim
  • Patent number: 7170308
    Abstract: The present invention optimizes the performance of integrated circuits by adjusting the circuit operating voltage using feedback on process/product parameters. To determine a desired value for the operating voltage of an integrated circuit, a preferred embodiment provides for on-wafer probing of one or more reference circuit structures to measure at least one electrical or operational parameter of the one or more reference circuit structures; determining an adjusted value for the operating voltage based on the measured parameter; and establishing the adjusted value as the desired value for the operating voltage. The reference circuit structures may comprise process control monitor structures or structures in other integrated circuits fabricated in the same production run. In an alternative embodiment, the one or more parameters are directly measured from the integrated circuit whose operating voltage is being adjusted.
    Type: Grant
    Filed: July 28, 2003
    Date of Patent: January 30, 2007
    Assignee: Altera Corporation
    Inventors: Irfan Rahim, Peter McElheny, John Costello
  • Patent number: 7153712
    Abstract: Programmable fuses for integrated circuits are provided. The fuses may be based on polysilicon or crystalline silicon fuse links coated with silicide or other conductive thin films. Fuses may be formed on silicon-on-insulator (SOI) substrates. A fuse may be blown by applying a programming current to the fuse link. The silicon or polysilicon in the fuses may be provided with a p-n junction. When a fuse is programmed, the silicide or other conductive film forms an open circuit. This forces current though the underlying p-n junction. Unlike conventional silicided polysilicon fuses, fuses with p-n junctions change their qualitative behavior when programmed. Unprogrammed fuses behave like resistors, while programmed fuses behave like diodes. The presence of the p-n junction allows sensing circuitry to determine in a highly accurate qualitative fashion whether a given fuse has been programmed.
    Type: Grant
    Filed: May 5, 2005
    Date of Patent: December 26, 2006
    Assignee: Altera Corporation
    Inventors: Lakhbeer S. Sidhu, Irfan Rahim
  • Patent number: 7142009
    Abstract: Adaptive regulated power supply voltages are applied to programmable logic integrated circuits. Control circuitry in a programmable logic IC generates control signals that are transmitted to an external voltage regulator. The voltage regulator generates one or more power supply voltages in response to the control signals. The values of control signals determine the target values of the supply voltages. The control circuitry can adapt the power supply voltages to compensate for temperature and process variations on the IC. The power supply voltages can be programmed by a manufacturer or by a user to achieve desired target values. The control circuitry can also put a programmable logic IC into a sleep mode by dropping the high supply voltage to a low value to reduce power consumption during periods of low usage.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: November 28, 2006
    Assignee: Altera Corporation
    Inventors: Jeffrey Watt, Irfan Rahim
  • Patent number: 7139997
    Abstract: Disclosed is a method for checking the operation of an IC mask generation algorithm in which at least a first identifier of the mask generation algorithm is associated with at least a first symbol that is not associated with generating a functional IC feature. The first symbol has a predetermined size and a predetermined shape. A predetermined location on a mask is also associated with the first symbol. A mask diagram on the mask is generated at least partially at the first predetermined location. The size and shape of the mask diagram is then compared with at least a portion of the first predetermined size and the first predetermined shape of the first symbol.
    Type: Grant
    Filed: May 11, 2004
    Date of Patent: November 21, 2006
    Assignee: Altera Corporation
    Inventors: Irfan Rahim, Bradley Jensen, Girish Venkitachalam, Hugh Sung-Ki O, Susan Falk, Priya Selvaraj
  • Patent number: 7135951
    Abstract: Integrated circuit inductors may be formed using a spiral layout on the surface of an interconnect dielectric stack. Conductive lines from two or more metal layers in the interconnect stack may be electrically connected using one or more via trenches. The via trench interconnection arrangement reduces the resistance of the inductor and increases the inductor's Q-factor. The Q-factor of the inductor may also be increased by placing a region of n-type and p-type wells or a metal plate region beneath the inductor to reduce power losses during operation. Shallow trench isolation may be used to reduce eddy currents and increase Q. The effects of copper dishing and trench blow-out may be used during inductor fabrication. A dual damascene fabrication process may be used.
    Type: Grant
    Filed: July 15, 2003
    Date of Patent: November 14, 2006
    Assignee: Altera Corporation
    Inventors: Lakhbeer S. Sidhu, Irfan Rahim
  • Patent number: 7129745
    Abstract: A programmable logic device (PLD) includes a delay circuit and a body-bias generator. The delay circuit has a delay configured to represent a delay of user circuit implement in the PLD. The body-bias generator is configured to adjust the body bias of a transistor within the user circuit. The body-bias generator adjusts the body bias of the transistor in response to a level derived from the signal propagation delay of the delay circuit.
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: October 31, 2006
    Assignee: Altera Corporation
    Inventors: David Lewis, Vaughn Betz, Irfan Rahim, Peter McElheny, Yow-Juang W. Liu, Bruce Pedersen
  • Publication number: 20060237784
    Abstract: An integrated circuit having an enhanced on-off swing for pass gate transistors is provided. The integrated circuit includes a core region that includes core transistors and pass gate transistors. The core transistors have a gate oxide associated with a first thickness, the pass transistors having a gate oxide associated with a thickness that is less than the first thickness. In one embodiment, the material used for the gate oxide of the pass gate transistors has a dielectric constant that is greater than four, while the material used for the gate oxide of the core transistors has a dielectric constant that is less than or equal to four. A method for manufacturing an integrated circuit is also provided.
    Type: Application
    Filed: April 25, 2005
    Publication date: October 26, 2006
    Inventors: Irfan Rahim, Yow-Juang Liu, Jeffrey Watt
  • Publication number: 20060119384
    Abstract: Techniques for combining volatile and non-volatile programmable logic into one integrated circuit (IC) are provided. An IC is segregated into two portions. A first block of programmable logic is configured by bits stored in on-chip non-volatile memory. A second block of programmable logic is configured by bits stored in off-chip memory. The function of IO banks on the IC is multiplexed between the two logic blocks of the IC. The programmable logic in the first block can be configured and fully functional in a fraction of the time that the programmable logic in the second block can be configured. The programmable logic in the first block can configure fast enough and have enough independence to assist in the configuration of the second block. The non-volatile memory can also provide security features to a user design, such as encryption.
    Type: Application
    Filed: December 2, 2004
    Publication date: June 8, 2006
    Applicant: Altera Corporation
    Inventors: Rafael Camarota, Irfan Rahim, Boon Ang, Thow Chong
  • Publication number: 20060001045
    Abstract: A configuration memory cell (“CRAM”) for a field programmable gate array (“FPGA”) integrated circuit (“IC”) device is given increased resistance to single event upset (“SEU”). A portion of the gate structure of the input node of the CRAM is increased in size relative to the nominal size of the remainder of the gate structure. Part of the enlarged gate structure is located capacitively adjacent to an N-well region of the IC, and another part is located capacitively adjacent to a P-well region of the IC. This arrangement gives the input node increased capacitance to resist SEU, regardless of the logical level of the input node. The invention is also applicable to any node of any type of memory cell for which increased resistance to SEU is desired.
    Type: Application
    Filed: July 1, 2004
    Publication date: January 5, 2006
    Inventors: Lakhbeer Sidhu, Irfan Rahim, Jeffrey Watt, John Turner
  • Publication number: 20050280437
    Abstract: A programmable logic device (PLD) includes a delay circuit and a body-bias generator. The delay circuit has a delay configured to represent a delay of user circuit implement in the PLD. The body-bias generator is configured to adjust the body bias of a transistor within the user circuit. The body-bias generator adjusts the body bias of the transistor in response to a level derived from the signal propagation delay of the delay circuit.
    Type: Application
    Filed: June 10, 2004
    Publication date: December 22, 2005
    Inventors: David Lewis, Vaughn Betz, Irfan Rahim, Peter McElheny, Yow-Juang Liu, Bruce Pedersen
  • Publication number: 20050270714
    Abstract: Integrated circuits are provided that have sensitive circuitry such as programmable polysilicon fuses. Electrostatic discharge (ESD) protection circuitry is provided that prevents damage or undesired programming of the sensitive circuitry in the presence of an electrostatic discharge event. The electrostatic discharge protection circuitry may have a power ESD device that limits the voltage level across the sensitive circuitry to a maximum voltage and that draws current away from the sensitive circuitry when exposed to ESD signals. The electrostatic discharge protection circuitry may also have an ESD margin circuit that helps to prevent current flow through the sensitive circuitry when the maximum voltage is applied across the sensitive circuitry.
    Type: Application
    Filed: June 3, 2004
    Publication date: December 8, 2005
    Inventors: Cheng-Hsiung Huang, Guu Lin, Shih-Lin Lee, Chih-Ching Shih, Irfan Rahim, Stephanie Tran
  • Publication number: 20050258862
    Abstract: A programmable logic device (PLD) includes mechanisms for adjusting or setting the body bias of one or more transistors. The PLD includes a body-bias generator. The body-bias generator is configured to set a body bias of one or more transistors within the programmable logic device. More specifically, the body-bias generator sets the body bias of the transistor(s) so as to trade off performance and power consumption of the transistor(s).
    Type: Application
    Filed: May 19, 2004
    Publication date: November 24, 2005
    Inventors: Irfan Rahim, Peter McElheny, Yow-Juang Liu, Bruce Pedersen
  • Patent number: 6963503
    Abstract: An EEPROM cell with reduced cell size and improved circuit performance includes a high-voltage (HV) capacitor, a low-voltage (LV) read path, and an HV write path, wherein either the HV capacitor is placed between the LV read path and the HV write path or the HV write path is placed between the LV read path and the HV capacitor. The EEPROM cell also includes a native floating-gate (FG) transistor in the LV read path. Using a native FG transistor in the LV read path results in further reduction in the cell size and improved circuit performance of the EEPROM cell.
    Type: Grant
    Filed: July 11, 2003
    Date of Patent: November 8, 2005
    Assignee: Altera Corporation.
    Inventors: Irfan Rahim, Veenu Shekhar