Patents Assigned to Broadcom
  • Patent number: 7130607
    Abstract: A method for adjusting a programmable mixer of a local oscillation module to reduce local oscillation leakage begins by determining at least one of: DC offset of an input signal of the programmable mixer and process mismatches between a first mixing stage and a second mixing stage. The method continues by determining operational characteristics mismatch between the first mixing stage and the second mixing stage based on the at least one of the DC offset and process mismatches. The method continues by generating a control signal to substantially compensate for the operational characteristics mismatch. The method continues by providing the control signal to a compensation module, wherein the compensation module modifies operational characteristics of at least one of the first and second mixing stages based on the control signal such that the operational characteristics of the first mixing stage substantially equals the operational characteristics of the second mixing stage.
    Type: Grant
    Filed: August 28, 2004
    Date of Patent: October 31, 2006
    Assignee: Broadcom Corporation
    Inventor: Shahla Khorram
  • Patent number: 7130953
    Abstract: An integrated circuit system (70) includes a processor (130) and a system bus (12) with a first complexity coupled to the processor. Apparatus for enabling communication between the processor and one or more devices through the system bus include a first device (90), a second device (80), and a first bus interface (72) coupled to the system bus (12), coupled to the first device (90) through a first bus (92) with a second complexity less than the first complexity and coupled to the second device (80) through a second bus (82) with a third complexity less than the first complexity.
    Type: Grant
    Filed: May 13, 2003
    Date of Patent: October 31, 2006
    Assignee: Broadcom Corporation
    Inventor: Brian Schoner
  • Patent number: 7131045
    Abstract: The present invention is directed to circuits and methods to efficiently conduct scan testing of integrated circuits in which first level packaging is varied to provide different versions of the integrated circuit. An integrated circuit is provided that includes at least one bond pad test circuit. The bond pad test circuit is coupled between a bond pad and functional components within an integrated circuit. In one embodiment, the bond pad test circuit includes a multiplexer and a D flip-flop in which the D input of the flip-flop is coupled to a bond pad. In another embodiment, the bond pad test circuit includes a multiplexer and a D flip-flop in which the D input of the flip-flop is coupled to the output of the multiplexer. A method for scan testing using an integrated circuit with a bond pad test circuit is also provided.
    Type: Grant
    Filed: August 14, 2003
    Date of Patent: October 31, 2006
    Assignee: Broadcom Corporation
    Inventor: Amar Guettaf
  • Patent number: 7129787
    Abstract: A power amplifier circuit including a first transistor, a second transistor, and a power control circuit. The first transistor includes a first input and a first output. The second transistor includes a second input coupled in series with the first output of the first transistor. The input circuit is coupled to the second input of the second transistor. The control circuit includes a time delay circuit and a variable source.
    Type: Grant
    Filed: April 16, 2004
    Date of Patent: October 31, 2006
    Assignee: Broadcom Corporation
    Inventor: Chris Nilson
  • Publication number: 20060242478
    Abstract: A technique for determining a symbol erasure threshold for a received communication signal containing symbol information is disclosed. The technique begins by performing a first threshold calculation to produce an initial symbol erasure threshold, then performing a first margin calculation to produce an initial symbol erasure margin and then modifying the initial symbol erasure threshold using the initial symbol erasure margin to produce a modified symbol erasure threshold. By then periodically modifying the modified symbol erasure threshold adaptive via updating the symbol erasure threshold and/or symbol erasure margin based on various error quantities, the technique can compensate for time-variant considerations, such as drifting noise levels.
    Type: Application
    Filed: June 26, 2006
    Publication date: October 26, 2006
    Applicant: Broadcom Corporation
    Inventors: Miguel Peeters, Geert Goris
  • Publication number: 20060237820
    Abstract: The present invention is directed to an apparatus and method for reducing a parasitic capacitance in an integrated circuit. The apparatus includes a substrate and a biasing device. The substrate has a circuit disposed thereon, wherein a first capacitance exists between the substrate and an element of the circuit. The biasing device DC biases a first portion of the substrate to a voltage different than a voltage of a second portion of the substrate, thereby inducing a second capacitance between the first portion of the substrate and the second portion of the substrate. The second capacitance is in series with the first capacitance.
    Type: Application
    Filed: June 23, 2006
    Publication date: October 26, 2006
    Applicant: Broadcom Corporation
    Inventor: Chun-Ying Chen
  • Patent number: 7126428
    Abstract: A multi-stage, variable gain amplifier whose linearity is relatively insensitive to variations in gain control is disclosed. The amplifier includes a primary cascoded pair of transistors for producing a primary output current from an input voltage as a function of a primary cascode control voltage. The amplifier further includes one or more secondary cascoded pairs of transistors coupled to the primary cascoded pair of transistors for producing one or more secondary output currents from the input voltage as a function of one or more secondary cascode control voltages. The output current of the RF circuit is a sum of the primary output current and the one or more secondary output currents.
    Type: Grant
    Filed: April 5, 2005
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventors: Li Lin, Arya Reza Behzad
  • Patent number: 7127624
    Abstract: Energy detect with auto pair select. The present invention is operable without ‘a priori’ knowledge of the pairs' connectivity. In addition, the present invention is operable within systems performing automatic detection of connectivity in systems that employ the Ethernet based media dependent interface crossover (MDIX). Where there has been some cross-over of pairs within the system, a situation not uncommon in many networks, the present invention is operable to perform energy management even without having any knowledge of the pair connectivity. Knowledge relating to the energy of multiple pairs is used to perform energy detect and management. A state machine operates in performing the analysis of the energy using a qualified energy level. The present invention is also operable within systems that do not employ auto-negotiation. In systems where auto-negotiation is performed, the present invention is performed before the auto-negotiation to determine if an operable partner exists within the network.
    Type: Grant
    Filed: August 13, 2001
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventors: Mark Berman, Richard Glen Thousand
  • Patent number: 7126947
    Abstract: A network switch that has a plurality of input ports that receive data packets. An external interface is connected to the plurality of input ports. The external interface externally transmits the data packets for processing, and receives the data packets after processing. A memory management unit is connected to the external interface and a plurality of output ports are connected to the memory management unit.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventors: Mohan Kalkunte, Shekhar Ambe, Soma Pullela
  • Patent number: 7127007
    Abstract: Multi-carrier modulation fiber optic systems constructed using a series of electrical carriers, modulating the data on the electrical carriers and combining the carriers to form a wideband signal. The wideband signal can then be intensity modulated on a laser and coupled to a fiber optic channel. A receiver may then receive the laser signal from the fiber optic channel and convert it into an electrical signal. Multi-carrier modulation may be applied to existing fiber channels, which may be of lower quality. Existing fiber channels may have characteristics which prevent or restrict the transmission of data using intensity modulation at certain frequencies. An adaptive multi-carrier modulation transmitter may characterize an existing fiber optic channel and ascertain the overall characteristics of the channel. The transmitter and receiver can then be configured to use various bandwidths and various modulations in order to match the transfer characteristic of the fiber channel.
    Type: Grant
    Filed: November 14, 2003
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventor: Oscar E. Agazzi
  • Patent number: 7126377
    Abstract: A source-follower transistor based buffer provides high linearity. A replica transistor is used to generate a replica voltage substantially equal to the output voltage of the buffer. The replica voltage is level shifted by a level shift circuit and applied at the drain of the source-follower transistor to improve the linearity of the buffer. The buffer may be used in conjunction with a switched-capacitor sampling circuit. A damping circuit may be used to reduce charge glitches due to sampling. The damping circuit may be a low pass filter. The buffer may be used in an interface circuit that produces an output signal from an input signal and controls the level of the output signal.
    Type: Grant
    Filed: February 16, 2006
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventors: Todd L. Brooks, Anilkumar V. Tammineedi
  • Patent number: 7127167
    Abstract: A system for management of bandwidth, cost control, and operational efficiency in a fiber optic, ethernet-based, TDMA communications system. The invention features an aggregating optical node between a central office and end users. The optical spectrum is divided according to end user, direction (i.e., upstream or downstream), and/or according to function (e.g., video or non-video). In an embodiment of the invention, a wavelength coupler can be used to couple multiple upstream wavelengths from respective end-user devices, for forwarding to a central office. Moreover, adaptive equalization can be used for noise cancellation purposes.
    Type: Grant
    Filed: July 5, 2002
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventors: Dolors Sala, Ajay Chandra V. Gummalla
  • Patent number: 7126319
    Abstract: A power supply multiplexing circuit including a first supply voltage input. A first pair of cascoded PMOS transistors are in series with the first supply voltage input. A first native NMOS transistor is in series with the first pair of cascoded PMOS transistors. Also, a second supply voltage input and a second pair of cascoded PMOS transistors are in series with the second supply voltage input; and a second native NMOS transistor in series with the second pair of cascoded PMOS transistors. The gates of the first and second native NMOS transistors are driven by two control signals out of phase with each other, and sources of the first and second native NMOS transistors are connected together to output an output voltage.
    Type: Grant
    Filed: February 11, 2005
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventor: Chun-Ying Chen
  • Patent number: 7127593
    Abstract: A method for conditionally performing a SIMD operation causing a predetermined number of result objects to be held in a combination of different ones of a plurality of destination stores, the method comprising receiving and decoding instruction fields to determine at least one source store, a plurality of destination stores and at least one control store, said source and destination stores being capable of holding one or a plurality of objects, each object defining a SIMD lane. Conditional execution of the operation on a per SIMD lane basis is controlled using a plurality of pre-set indicators of the at least one control store designated in the instruction, wherein each said pre-set indicator i controls a predetermined number of result lanes p, where p takes a value greater than or equal to two. A predetermined number of result objects are sent to the destination stores such that the predetermined number of result objects are held by a combination of different ones of the plurality of destination stores.
    Type: Grant
    Filed: April 11, 2002
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventor: Sophie Wilson
  • Patent number: 7127222
    Abstract: A method for adjusting automatic gain control of a radio receiver begins by determining power level of a radio frequency (RF) signal received by the radio receiver to produce a determined power level. The method then continues by comparing the determined power level with a plurality of power thresholds to determine whether an automatic gain adjustment is needed. The method then continues, when the automatic gain adjustment is needed, by determining, from the comparing the determined power level with the plurality of power thresholds, a sign of the automatic gain adjustment. The method continues by determining, from the comparing the determined power level with the plurality of power thresholds, a magnitude of the automatic gain adjustment. The method continues by addressing a gain adjustment look up table for at least a portion of the radio receiver based on the magnitude to produce a gain setting.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventors: Hea Joung Kim, Paul Anthony Lettieri, Brima B. Ibrahim
  • Patent number: 7127648
    Abstract: A method for determining whether a physical layer device under test is defective may include establishing a closed communication path between a verified physical layer device and the physical layer device under test via an optical interface of the verified physical layer device and an optical interface of the physical layer device under test. Alternately, the electrical interface may also be used for testing. A packet generator may transmit test packets over the established closed communication path and at least a portion of the test packets from the physical layer device under test may be received by the verified physical layer device. Subsequently, the verified physical layer device may compare at least a portion of the received test packets with at least a portion of the generated test packets in order to determine whether the physical layer device is defective or operational.
    Type: Grant
    Filed: October 8, 2002
    Date of Patent: October 24, 2006
    Assignee: Broadcom Corporation
    Inventors: Hongtao Jiang, Tuan Hoang
  • Publication number: 20060234564
    Abstract: A connector device (for example, a jack) is provided with a sensing mechanism that detects mating of another connector to the connector device, and differentiates between matching and non-matching connectors. The sensing mechanism generates a signal to indicate that a non-matching connector has been mated with the connector device.
    Type: Application
    Filed: April 15, 2005
    Publication date: October 19, 2006
    Applicant: Broadcom Corporation
    Inventors: Art Pharn, James Muth, Ross Nagarasan, Richard Togashi
  • Patent number: 7123177
    Abstract: A system and method is provided for stabilizing high order sigma delta modulators. The system includes an integrator having a limiter in the feedback path of the integrator. The integrator combines an input signal with a feedback signal generated by the limiter to produce an integrated output signal. The output signal is output to the next component of the sigma delta modulator. In addition, the output signal is fed back through the limiter. When an output signal received in the feedback path by the limiter exceeds the threshold value of the limiter, the limiter is activated and clamps the output signal to produce a limited signal. The limited signal is combined with the input signal to the integrator to produce the output signal.
    Type: Grant
    Filed: August 14, 2003
    Date of Patent: October 17, 2006
    Assignee: Broadcom Corporation
    Inventors: Taiyi Cheng, Josephus van Engelen, Minsheng Wang
  • Patent number: 7124296
    Abstract: An architecture and a method for cryptography acceleration is disclosed that allows significant performance improvements without the use of external memory. Specifically, the chip architecture enables “cell-based” processing of random-length IP packets. The IP packets, which may be of variable and unknown size, are split into fixed size “cells.” The fixed-size cells are then processed and reassembled into packets. The cell-based packet processing architeture of the present invention allows the implementation of a processing pipeline that has known processing throughput and timing characteristics, thus making it possible to fetch and process the cells in a predictable time frame. The architecture is scalable and is also independent of the type of cryptography performed. The cells may be fetched ahead of time (pre-fetched) and the pipeline may be staged in such a manner that attached (local) memory is not required to store packet or control parameters.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: October 17, 2006
    Assignee: Broadcom Corporation
    Inventors: Suresh Krishna, Christopher Owen
  • Patent number: 7123877
    Abstract: A baseband controller includes a microsequencer that is formed to include special hardware resources and a configuration that facilitates using the micro-sequencer as a real-time baseband controller. The microsequencer includes a 72-bit correlator that way also be used as an accumulator. The correlator is able to communicate with a 72-bit arithmetic logic unit, enabling the correlator to act as an accumulator, as well as a plurality of clocks and timers that facilitate the timing functionality to satisfy Bluetooth specifications. More specifically, the microsequencer includes at least four clocks and eight times. The four clocks include an externally driven Bluetooth clock, an externally driven real-time clock, a native Bluetooth clock and a native real-time clock. The microsequencer further includes at least four registers for temporarily storing computational data. The storage registers have different sizes for storing different sized packets of computational data.
    Type: Grant
    Filed: November 8, 2001
    Date of Patent: October 17, 2006
    Assignee: Broadcom Corporation
    Inventor: John Lin