Patents Assigned to Broadcom
  • Patent number: 7120155
    Abstract: A network of switches having a first switch having a first memory interface and a first expansion port. The network also has an expansion bus having a first expansion bus interface and a second expansion bus interface. The first expansion bus interface is connected to the first expansion port. A second switch has a second memory interface and a second expansion port. The second expansion port is connected to the second expansion bus interface, thereby connecting the first switch to the second switch, wherein the expansion bus allows the first switch to directly access the second memory interface through the second switch and the second switch to directly access the first memory interface through the first switch.
    Type: Grant
    Filed: April 6, 2001
    Date of Patent: October 10, 2006
    Assignee: Broadcom Corporation
    Inventors: Michael Sokol, William Chien
  • Patent number: 7119620
    Abstract: In an RF communication system, aspects of constant or proportional to absolute temperature biasing for minimizing transmitter output power variation may comprise configuring at least one current source to provide a temperature dependent current, where the current may be constant with temperature or vary proportionally to absolute temperature. A control voltage that may be generated by an operational amplifier may be fed back to control the current source. An input reference voltage may also be generated for the operational amplifier by utilizing PN junction characteristics of at least one bipolar junction transistor. Resistance may be adjusted to allow operation of the current source at a plurality of different supply voltages, including the different supply voltages that may be less than 1.2 volts, for example. Additionally, adjusting the resistance may also allow the current to be constant with temperature or vary with temperature.
    Type: Grant
    Filed: November 30, 2004
    Date of Patent: October 10, 2006
    Assignee: Broadcom Corporation
    Inventor: Michael (Meng-An) Pan
  • Patent number: 7119750
    Abstract: A computer apparatus for receiving a removable communication card such as a radio card or a modem card. A radio or modem is self-contained inside a housing of the communication card and has an electrical interface for communicating information to and from the computer apparatus. The computer apparatus receives the communication card such that it engages the electrical interface. These contacts automatically connect the communication card to an appropriate antenna, telephone or telephone line. A radio communication card is connected to the appropriate antenna for the type and frequency of the radio. A modem card is connected to a standard telephone line, a cellular phone, or an antenna for a cellular phone if the cellular phone is also disposed within the housing of the modem communication card. Additionally, a switching matrix can be used to connect one set of contacts on a radio card or a modem card to one or more of a plurality of antennas and telephone lines.
    Type: Grant
    Filed: September 22, 2005
    Date of Patent: October 10, 2006
    Assignee: Broadcom Corporation
    Inventors: Patrick W. Kinney, Ronald L. Mahany, Guy J. West
  • Patent number: 7119631
    Abstract: Off-chip LC circuit for lowest ground and VDD impedance for power amplifier. A novel approach is made by which a chip to PCB (Printer Circuit Board) interface may be made such that the ground and VDD potential levels are effectively brought onto the die of the chip such that a true ground potential is maintained within the chip. This off-chip LC circuit operates cooperatively with an on-chip decoupling capacitor to reduce the overall effective inductance of the bond wires employed to bring signal and voltage levels from the die to the chip exterior. This circuit ensures a relatively low impedance for a PA (Power Amplifier) that is implemented within chip thereby providing for improved performance.
    Type: Grant
    Filed: May 12, 2004
    Date of Patent: October 10, 2006
    Assignee: Broadcom Corporation
    Inventors: Jesus Alfonso Castaneda, Qiang (Tom) Li
  • Patent number: 7120410
    Abstract: A Radio Frequency (RF) receiver includes a low noise amplifier (LNA) and a mixer coupled to the output of the LNA. The gain of the LNA is adjusted to maximize signal-to-noise ratio of the mixer and to force the mixer to operate well within its linear region when an intermodulation interference component is present. The RF receiver includes a first received signal strength indicator (RSSI_A) coupled to the output of the mixer that measures the strength of the wideband signal at that point. A second received signal strength indicator (RSSI_B) couples after the BPF and measures the strength of the narrowband signal. The LNA gain is set based upon these signal strengths. By altering the gain of the LNA by one step and measuring the difference between a prior RSSI_B reading and a subsequent RSSI_B? reading will indicate whether intermodulation interference is present.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: October 10, 2006
    Assignee: Broadcom Corporation
    Inventor: Hong Shi
  • Patent number: 7120412
    Abstract: A phase-locked loop circuit includes an array of selectable capacitors formed within the phase-locked loop circuit to enable the phase-locked loop circuit to provide a degree of coarse frequency control by adding or removing capacitors and a degree of fine frequency control by sinking or sourcing current from a charge pump into a loop filter. A finite state machine is provided within a voltage controlled oscillator calibration circuit that communicates with an external baseband processor to initiate a calibration process, and further to determine how many capacitors of an array of capacitors if formed within the phase-locked loop circuit should be coupled to provide the coarse frequency control.
    Type: Grant
    Filed: November 25, 2002
    Date of Patent: October 10, 2006
    Assignee: Broadcom Corporation
    Inventor: Seema Butala Anand
  • Patent number: 7120420
    Abstract: A process of creating incentives for wireless hotspots by a service provider is disclosed. An access point is provided to a wireless hotspot for wireless devices to wirelessly connect to a larger network in a publicly accessible location. Use of the access point for a portable device is authenticated by requesting submission of an account identifier to the service provider and billing data for a user of the portable device for use of the access point is generated. Use statistics are evaluated of the access point of the wireless hotspot by portables devices and an inducement is provided to the publicly accessible location based on the evaluated use statistics.
    Type: Grant
    Filed: August 12, 2004
    Date of Patent: October 10, 2006
    Assignee: Broadcom Corporation
    Inventors: Jeyhan Karaoguz, Nambi Seshadri
  • Patent number: 7120203
    Abstract: A dual link transmitter constructed according to the present invention employs a single Phase Locked Loop (PLL) to service both a primary link and a secondary link during dual link mode operations. The structure of the dual link transmitter includes both a primary link PLL and a secondary link PLL. The primary link PLL produces a primary link clock and the secondary link PLL produces a secondary link clock. During dual single link operations, the primary link clock is used to service the primary link while the secondary link clock is used to service the secondary link. However, during dual link operations, the primary link clock is used to service both the primary link and the secondary link.
    Type: Grant
    Filed: May 14, 2002
    Date of Patent: October 10, 2006
    Assignee: Broadcom Corporation
    Inventors: Jeffrey Bauch, Richard Berard, Christopher R. Pasqualino, Stephen G. Petilli
  • Patent number: 7119726
    Abstract: An error feedback circuit includes a first summer receiving an analog input signal and a feedback signal and outputting a summed signal. A quantizer receives the summed signal and outputs a quantized output signal. A limiter receives the summed signal and outputs a limited summed signal. The limiter limits the limited summed signal to ?* (maximum value of input signal), ?>1. A second summer receives the limited summed signal and the output signal and outputs an error signal. A filter receives the error signal and outputting the feedback signal. Typically, 1.0<?<2.0, more preferably 1.4<?<1.6. The filter has a transfer function of H1(z)=2z?1?z?2.
    Type: Grant
    Filed: October 17, 2005
    Date of Patent: October 10, 2006
    Assignee: Broadcom Corporation
    Inventor: Minsheng Wang
  • Publication number: 20060220738
    Abstract: A method and apparatus are provided for enabling a transmitter to have a substantially linear magnitude response and a substantially linear phase response. The transmitter includes first and second programmable gain amplifiers (PGAs). The first PGA is tuned to have a resonant frequency that is less than an operating frequency of the first PGA. The second PGA is tuned to have a resonant frequency that is greater than an operating frequency of the second PGA. A magnitude response at an output of the first PGA and a magnitude response at an output of the second PGA combine to provide a substantially linear magnitude response across a frequency range that includes the operating frequency of the first or second PGA. According to an embodiment, the first and second PGAs have the same operating frequency.
    Type: Application
    Filed: March 31, 2005
    Publication date: October 5, 2006
    Applicant: Broadcom Corporation
    Inventor: Meng-An Pan
  • Publication number: 20060223472
    Abstract: The present invention relates to a DC offset canceling circuit. In one aspect of the invention, a DC offset canceling circuit with independently configurable gain and roll-off frequency is provided. In one embodiment of the present invention, the DC offset canceling circuit is used in the receive path of a down-conversion wireless receiver. In another aspect of the invention, a method for independently varying the gain and the roll-off frequency of the DC offset canceling circuit is provided. In one embodiment, the method is used to independently operate a gain control scheme and a DC offset cancellation strategy in a DC canceling circuit.
    Type: Application
    Filed: March 30, 2006
    Publication date: October 5, 2006
    Applicant: Broadcom Corporation
    Inventors: Amit Bagchi, Rohit Gaikwad
  • Patent number: 7116176
    Abstract: A system for generating multiple synthesized clocks having an input terminal for receiving a reference signal, a phase locked loop circuit coupled to the input signal terminal, where the phase locked loop circuit is capable of generating a plurality of output signals that are frequency locked to the reference signal and having a plurality of different phases, a phase rotator coupled to the phase locked loop circuit, where the phase rotator generates an even greater plurality of phases.
    Type: Grant
    Filed: June 15, 2004
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventors: Siavash Fallahi, Chun Ying Chen, Mark J. Chambers
  • Patent number: 7116742
    Abstract: A method and a timing recovery system for generating a set of clock signals in a system which includes a set of subsystems. Each of the subsystems includes an analog section. The set of clock signals includes a set of sampling clock signals. Each of the analog sections operates in accordance with a corresponding one of the sampling clock signals. For each of the sampling clock signals, a phase error is generated from a corresponding phase detector. The phase errors are filtered by a set of corresponding loop filters. The filtered phase errors are provided to a set of corresponding oscillators to generate phase control signals. The phase control signals are provided to a set of corresponding phase selectors to generate the sampling clock signals.
    Type: Grant
    Filed: January 21, 2002
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventor: Oscar E. Agazzi
  • Patent number: 7116945
    Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventors: Shervin Moloudi, Ahmadreza Rofougaran, Maryam Rofougaran
  • Patent number: 7117292
    Abstract: A first-in, first-out (FIFO) unit switches between strobe sources. The FIFO uses a multiplexer to switch between two or more strobes so that different data strobes may be used with the FIFO to strobe in the data. In one implementation, the FIFO uses four data latches to strobe in data bits and output a pair of data bits onto the internal bus each half clock cycle.
    Type: Grant
    Filed: April 12, 2004
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventor: James D. Kelly
  • Patent number: 7116202
    Abstract: An inductor circuit includes a magnetic interface generator that generates a magnetic interface at a center frequency f0. The magnetic interface generator is a passive array of spirals that are deposited on one layer of a multi-layer substrate. The magnetic interface is generated in a plane at a distance Z above the surface of the substrate layer that it is printed on, where the antenna is printed on a second layer of the multi-layer substrate. The distance Z where the magnetic interface is created is determined by the cell size of the spiral array, where the cell size is based on the spiral arm length and the spacing S between the spirals. The center frequency of the magnetic interface is determined by the average track length DAV of the spirals in the spiral array. The spacing S of the spiral array is chosen to project the magnetic interface to the second layer in the multi-layer substrate so as to effect performance of an inductor that printed on the second layer.
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventors: Nicolaos G. Alexopoulos, Harry Contopanagos, Chryssoula Kyriazidou
  • Patent number: 7116666
    Abstract: An apparatus and process for relabelling and redirecting at least some of the read transaction data frames and the write transaction write data and transfer ready frames in a network so as to bypass a storage manager and pass directly between the client and a storage device via a switch. This eliminates the storage manager as a bottleneck. Some embodiments redirect every read and write transaction, and others redirect only large transactions, or only ones not stored in cache or when latency gets too high. Redirection is accomplished by transmission from the storage manager to a switch redirection commands that contain old and new address data. When a frame to be redirected comes in, its address is compared to the old address data. If there is a match, the new address data is substituted and the frame is passed to a conventional routing process to be routed so as to bypass the storage manager.
    Type: Grant
    Filed: January 19, 2005
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventors: Lani William Brewer, John Gifford Logan
  • Patent number: 7115952
    Abstract: An integrated receiver with channel selection and image rejection substantially implemented on a single CMOS integrated circuit is described. A receiver front end provides programable attenuation and a programable gain low noise amplifier. Frequency conversion circuitry advantageously uses LC filters integrated onto the substrate in conjunction with image reject mixers to provide sufficient image frequency rejection. Filter tuning and inductor Q compensation over temperature are performed on chip. The filters utilize multi track spiral inductors. The filters are tuned using local oscillators to tune a substitute filter, and frequency scaling during filter component values to those of the filter being tuned. In conjunction with filtering, frequency planning provides additional image rejection. The advantageous choice of local oscillator signal generation methods on chip is by PLL out of band local oscillation and by direct synthesis for in band local oscillator.
    Type: Grant
    Filed: July 1, 2005
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventors: Agnes N. Woo, Kenneth R. Kindsfater, Fang Lu
  • Patent number: 7116729
    Abstract: A method and apparatus for trimming of a local oscillation within a radio frequency integrated circuit (RFIC) includes processing that begins when an RFIC receives a radio frequency (RF) signal having a known frequency. The processing then continues when the RFIC mixes the RF signal with a receiver local oscillation to produce a low intermediate frequency (IF) signal, which may have a carrier frequency of zero (i.e., a baseband signal) or up to a few mega Hertz). The processing then continues when the RFIC demodulates the low IF signal to produce demodulated data. The processing then continues as the RFIC determines a DC offset from the demodulated data, where the DC offset is reflective of the difference between the known frequency and the frequency of the receiver local oscillation. The processing then continues as the RFIC adjusts the receiver local oscillation to reduce the DC offset when the DC offset compares unfavorably with an allowable offset threshold.
    Type: Grant
    Filed: September 13, 2002
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventors: Brima Ibrahim, Henrik T. Jensen
  • Patent number: 7116259
    Abstract: An analog-to-digital converter (ADC) disposed in a data reception path to convert data from an analog format to a digital format is switched between two or more power modes to conserve power when data is not being received. ADC stays in a lower power-lower precision mode until an inbound data is detected, at which time the ADC switches to a higher power-higher precision mode to convert the data. Once data conversion is completed, the ADC switches back to the lower power-lower precision mode to conserve power.
    Type: Grant
    Filed: May 18, 2004
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventors: Srinivasa H. Garlapati, Paul Anthony Lettieri, Jason A. Trachewsky, Gregory H. Efland, Tom W. Kwan