Patents Represented by Attorney Mitch Harris, Atty at Law, LLC
  • Patent number: 7657722
    Abstract: A method and apparatus for automatically securing non-volatile (NV) storage in an integrated circuit provides improved resistance to code copying and reverse-engineering attacks. External interfaces that provide read access to the NV storage are be disabled, for a predetermined time after a reset or other initialization signal is received. An internal lock state bit or key is checked as well as an external lock prevent indication. If the lock prevent indication is not received, or the internal lock state bit is already set, then the integrated circuit is operated under a locked condition, in which external access to the NV storage values is prevented. The lock prevent indication may be a signal provided during reset of the integrated circuit on a terminal that is used for another purpose after initialization of the integrated circuit.
    Type: Grant
    Filed: June 30, 2007
    Date of Patent: February 2, 2010
    Assignee: Cirrus Logic, Inc.
    Inventors: Edwin De Angel, Jorge Antonio Abullarade, Jean Charles Pina, Rahul Singh
  • Patent number: 7656687
    Abstract: A modulated transformer-coupled gate control signaling method and apparatus provides reduction of circuit complexity and robust design characteristics in switching power circuits having a transformer-coupled gate drive. A modulated control signal at a rate substantially higher than the switching circuit gate control rate is provided from the controller circuit to a demodulator via transformer coupling. Power for the demodulator can be obtained by rectifying the modulated control signal at the demodulator, or from another transformer winding. The modulation scheme is chosen to have a DC average value of zero, eliminating any magnetization current management requirements. The modulated control signal may carry redundant control information and/or may encode additional information to provide a more sophisticated gate drive control, such as oversampled gate control information.
    Type: Grant
    Filed: December 11, 2007
    Date of Patent: February 2, 2010
    Assignee: Cirrus Logic, Inc.
    Inventor: John L. Melanson
  • Patent number: 7657664
    Abstract: A computer implemented method, an apparatus, and a computer usable program product for tracking device driver requests in a data processing system is provided. A controller receives a request from a device driver. The controller associates a timestamp and at least one pointer to the request, wherein the timestamp indicates a time the request is received by an operating system. The controller then links the request from the device driver in a queue in the operating system, wherein the pointer identifies the location of the request in the queue.
    Type: Grant
    Filed: March 8, 2007
    Date of Patent: February 2, 2010
    Assignee: International Business Machines Corporation
    Inventors: Brian W. Hart, Anil Kalavakolanu
  • Patent number: 7657893
    Abstract: An accounting method and multi-threaded processor include a mechanism for accounting for processor resource usage by threads within programs. Relative resource use is determined by detecting a particular cycle state of threads active within the processor. If instructions are dispatched for all threads or no threads, the processor cycle is accounted equally to all threads. Alternatively if no threads are in the particular cycle state, the accounting may be made using a prior state, or in conformity with ratios of the threads' priority levels. If only one thread is in the particular cycle state, that thread is accounted the entire processor cycle. If multiple threads are dispatching, but less than all threads are dispatching, the processor cycle is billed evenly across the dispatching threads.
    Type: Grant
    Filed: April 23, 2003
    Date of Patent: February 2, 2010
    Assignee: International Business Machines Corporation
    Inventors: William Joseph Armstrong, Michael Stephen Floyd, Ronald Nick Kalla, Larry Scott Leitner, Balaram Sinharoy
  • Patent number: 7644708
    Abstract: A bow maintenance press and method provides operation adaptable to various bow designs using adaptable bow press fingers that apply force to the bow limb ends. The bow limb end fingers may be interchangeable to supply different shapes or sizes and/or may provide adjustment in at least a limb end width or length, such that substantially equal force is applied to the bow limb ends of a bow having at least one split limb end. The fingers may be tiltable to adjust for differing limb end lengths and may be spring-loaded to ease in initial placement and retention of a bow before it is compressed.
    Type: Grant
    Filed: December 30, 2008
    Date of Patent: January 12, 2010
    Inventor: Leon Monroe Pittman
  • Patent number: 7646082
    Abstract: A multi-layer circuit substrate and method having improved transmission line integrity and increased routing density uses a selectively applied transmission line reference plane metal layer to achieve signal path shielding and isolation, while avoiding drops in impedance due to capacitance between large diameter vias and the transmission line reference plane metal layer. The transmission line reference plane defines voids above (or below) the signal-bearing plated-through holes (PTHs) that pass through a rigid substrate core, so that the signals are not degraded by an impedance mismatch that would otherwise be caused by shunt capacitance from the top (or bottom) of the signal-bearing PTHs to the transmission line reference plane. For voltage-plane bearing PTHs, no voids are introduced, so that signal path conductors can be routed above or adjacent to the voltage-plane bearing PTHs, with the transmission line reference plane preventing shunt capacitance between the signal path conductors and the PTHs.
    Type: Grant
    Filed: May 22, 2007
    Date of Patent: January 12, 2010
    Assignee: International Business Machines Corporation
    Inventors: Sungjun Chun, Anand Haridass, Roger D. Weekly
  • Patent number: 7636556
    Abstract: A digital transmission circuit and method providing selectable power consumption via multiple weighted driver slices improves the flexibility of an interface while reducing power consumption when possible. A cascaded series of driver stages is provided by a set of parallel slices and a control logic that activates one or more of the slices, which combine to produce a cascaded active driver circuit. The power consumption/drive level selectability of the slice combination provides a driver that can be fine-tuned to particular applications to provide the required performance at a minimum power consumption level.
    Type: Grant
    Filed: January 16, 2008
    Date of Patent: December 22, 2009
    Assignee: International Business Machines Corporaion
    Inventors: Juan-Antonio Carballo, Kevin John Nowka, Ivan Vo, Seung-moon Yoo
  • Patent number: 7634589
    Abstract: A method provides adaptive interrupt latency to improve performance in a processing system. A ration of transmit queue depth to receive queue depth of the adapter is compared to its historical value in order to provide an estimate of processor load. The estimated processor load is then used to set a parameter that controls the frequency of an interrupt generator, which may be controlled by setting an interrupt queue depth threshold, packet frequency threshold or interrupt hold-off time value. The historical value may be predetermined, user-settable, obtained during a calibration interval or obtained by taking a long-term average of the ratio.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: December 15, 2009
    Assignee: International Business Machines Corporation
    Inventors: Vaijayanthimala K. Anand, Janice Marie Girouard, Emily Jane Ratliff
  • Patent number: 7620510
    Abstract: A pulsed ring oscillator circuit for storage cell read timing evaluation provides read strength information. A pulse generator is coupled to a bitline to which the storage cell to be measured is connected. The storage cell thereby forms part of the ring oscillator and the read strength of the storage cell is reflected in the frequency of oscillation. A pulse regeneration circuit is included in the ring so that the storage cell read loading does not cause the oscillation to decay. Alternatively, a counter may be used to count the number of oscillations until the oscillations decay, which also yields a measure of the read strength of the storage cell. The pulse generator may have variable output current, and the current varied to determine a change in current with the storage cell enabled and disabled that produces the same oscillation frequency. The read current is the difference between currents.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: November 17, 2009
    Assignee: International Business Machines Corporation
    Inventors: Gary D. Carpenter, Jente B Kuang, Kevin J. Nowka, Liang-Teck Pang
  • Patent number: 7606377
    Abstract: A method and system for surround sound beam-forming using vertically displaced drivers provides a low cost alternative to present external surround array systems. A pair of vertically displaced speaker drivers is supplied with surround and main channel information in a controlled phase relationship with respect to each driver such that the surround channel information is propagated in a directivity pattern substantially differing from that of the main channel information. The main channel information is generally directed at a listening area, while the surround channel information is directed away from the listening area and is substantially attenuated in the direction of the listening area, so that the surround channel information is heard as a diffuse reflected field. An electronic network provides for control of the surround channel phase relationship and combining of main and surround signals for providing inputs to individual power amplifiers for each driver.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: October 20, 2009
    Assignee: Cirrus Logic, Inc.
    Inventor: John L. Melanson
  • Patent number: 7606380
    Abstract: A method and system for sound beam-forming using internal device speakers in conjunction with external speakers provides a low cost alternative to present external surround array systems. A processing circuit within an audio device or audio/visual (AV) device such as a digital television (DTV) generates signals for internal and external speakers that phase-align the internal speakers with the external speakers for beam-forming. The beam may be a surround beam directed away from a listening position so that surround channel information is only heard as reflections. Alternatively, the beam may be a “night mode” beam that concentrates sound at a particular location or multiple beams may be formed for picture-in-picture or other applications where it is desirable to provide multiple isolated listening locations.
    Type: Grant
    Filed: April 28, 2006
    Date of Patent: October 20, 2009
    Assignee: Cirrus Logic, Inc.
    Inventor: John L. Melanson
  • Patent number: 7598774
    Abstract: An limited-switch dynamic logic (LSDL) circuit provides reduced power consumption by reducing clock power dissipation. By clocking LSDL gates with a clock signal having a reduced voltage swing in the evaluation phase, the LSDL gates are permitted to operate, while reducing the clock power consumption dramatically. Since clock power consumption dominates in LSDL circuits, the reduction in clock power dissipation results in a significant reduction in overall circuit power consumption. The reduced swing clock is produced at a plurality of local clock buffers by supplying the local clock buffers with an extra power supply rail that is switched onto the clock distribution lines by the local clock buffers in response to the full-swing evaluate phase clock received from the global clock distribution network by the local clock buffers.
    Type: Grant
    Filed: June 25, 2008
    Date of Patent: October 6, 2009
    Assignee: International Business Machines Corporation
    Inventors: Wendy Ann Belluomini, Aniket Mukul Saha
  • Patent number: 7597094
    Abstract: A compound bow maintenance press and method for compressing a compound bow from the bow limb ends provides a shop-installable bow press that prevents damage to the bow riser and limbs during service. The press contacts the bow only at the ends of the bow limbs and compresses the bow from outside of the curvature of the bow, providing clear access to the bow strings and a press that can be secured or stood on a workbench or a floor stand. The bow press can be operated by an electric motor or a hand crank and may include a worm gear drive system that provides for adjusting a telescoping member having arms extending to compress the bow limb ends. A limb end fixture is attached to or integrated with each arm, and provides a slot that accepts the bow limb end pulleys.
    Type: Grant
    Filed: September 18, 2006
    Date of Patent: October 6, 2009
    Inventor: Leon Monroe Pittman
  • Patent number: 7599462
    Abstract: A hybrid analog/digital phase-lock loop with high-level event synchronization provides a mechanism for generating a low-jitter clock from a timing reference that has a high jitter level and synchronizing the output clock to high-level events. A numerically-controlled analog oscillator provides a clock output and a counter divides the frequency of the clock output to provide input to a digital phase-frequency detector for detecting an on-going phase-frequency difference between the timing reference and the output of the counter. A synchronization circuit detects or receives a high-level event signal, and resets the on-going phase-frequency difference and optionally the counter to synchronize the clock output with the events. The synchronization circuit may have an arming input to enable the synchronization circuit to signal a next event. Another clock output divider may be included to generate a timing reference output, and the other clock divider also reset in response to a detected event.
    Type: Grant
    Filed: April 24, 2007
    Date of Patent: October 6, 2009
    Assignee: Cirrus Logic, Inc.
    Inventor: John L. Melanson
  • Patent number: 7596681
    Abstract: A processor and processing method for reusing arbitrary sections of program code provides improved upgrade capability for systems with non-alterable read only memory (ROM) and a more flexible instruction set in general. A specific program instruction is provided in the processor instruction set for directing program execution to a particular start address, where the start address is specified in conjunction with the specific program instruction. An end address is also specified in conjunction with the specific program instruction and the processor re-directs control upon completion of code execution between the start and end address to either another specified address, or to a stored program counter value corresponding to the next instruction in sequence after the specific program instruction. A loop count may also be supplied for repeatedly executing the code between the start and end address until the count has expired.
    Type: Grant
    Filed: March 24, 2006
    Date of Patent: September 29, 2009
    Assignee: Cirrus Logic, Inc.
    Inventors: Ronald D. Wiese, Nariankadu D. Hemkumar, Sanjay Pillay
  • Patent number: 7576569
    Abstract: A circuit for dynamically monitoring the operation of an integrated circuit under differing temperature, frequency, and voltage (including localized noise and droop), and for detecting early life wear-out mechanisms (e.g., NBTI, hot electrons).
    Type: Grant
    Filed: October 13, 2006
    Date of Patent: August 18, 2009
    Assignee: International Business Machines Corporation
    Inventors: Gary D. Carpenter, Alan J. Drake, Harmander S. Deogun, Michael S. Floyd, Norman K. James, Robert M. Senger
  • Patent number: 7564259
    Abstract: A digital circuit with dynamic power and performance control via per-block selectable operating voltage level permits dynamic tailoring of operating power to processing demand and/or compensation for process variation. A set of processing blocks having a power supply selectable from two different power supply voltage levels is provided. The power level of the overall circuit is set by selecting the power supply voltage for each block to yield a combination of blocks that meets operating requirements. Alternatively, one circuit per pair from a set of pairs of redundant logic blocks supplied by the different power supply voltage levels can be selected to meet the operating requirements. The unselected blocks can be disabled by disabling foot devices or disabling transitions at the inputs to the unselected blocks. Performance measurement and feedback circuits can be included to tune the power consumption and performance level of the circuit to meet an expected level.
    Type: Grant
    Filed: December 13, 2005
    Date of Patent: July 21, 2009
    Assignee: International Business Machines Corporation
    Inventors: Kanak B. Agarwal, Damir A. Jamsek, Kevin J. Nowka
  • Patent number: 7564739
    Abstract: A storage cell design evaluation circuit including a wordline timing and cell access detection circuit provides accurate information about state changes in static storage cells. A storage cell test row includes the access detection circuit, which provides the same loading during an access operation as the other cells in the array. The access detection circuit provides an output that may be probed without affecting the timing, read stability or writeability of the cell. The test row can test the clock and/or address timing of the row and may include a separate power supply rail for the row wordline driver, so that variation of access timing, read stability and writeability with wordline strength/access voltage can be determined. Multiple test rows may be cascaded among columns to provide a long delay line or ring oscillator for improved measurement resolution.
    Type: Grant
    Filed: May 21, 2008
    Date of Patent: July 21, 2009
    Assignee: International Business Machines Corporation
    Inventors: Sebastian Ehrenreich, Jente B Kuang, Chun-Tao Li, Hung Kai Ngo
  • Patent number: 7561483
    Abstract: An internally asymmetric method for evaluating static memory cell dynamic stability provide a mechanism for raising the performance of memory arrays beyond present levels/yields. By altering the internal symmetry of a static random access memory (SRAM) memory cell, operating the cell and observing changes in performance caused by the asymmetric operation, the dynamic stability of the SRAM cell can be studied over designs and operating environments. The asymmetry can be introduced by splitting one or both power supply rail inputs to the cell and providing differing power supply voltages or currents to each cross-coupled stage. Alternatively or in combination, the loading at the outputs of the cell can altered in order to affect the performance of the cell. A memory array with at least one test cell can be fabricated in a production or test wafer and internal nodes of the memory cell can be probed to provide further information.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: July 14, 2009
    Assignee: International Business Machines Corporation
    Inventors: Rajiv V. Joshi, Qiuyi Ye, Anirudh Devgan
  • Patent number: 7560951
    Abstract: A characterization array circuit provides accurate threshold voltage distribution values for process verification and improvement. The characterization array includes a circuit for imposing a fixed drain-source voltage and a constant channel current at individual devices within the array. A circuit for sensing the source voltage of the individual device is also included within the array. The statistical distribution of the threshold voltage is determined directly from the source voltage distribution by offsetting each source voltage by a value determined by completely characterizing one or more devices within the array. The resulting methodology avoids the necessity of otherwise characterizing each device within the array, thus reducing measurement time dramatically.
    Type: Grant
    Filed: February 12, 2008
    Date of Patent: July 14, 2009
    Assignee: International Business Machines Corporation
    Inventors: Kanak B Agarwal, Sani R Nassif