Patents Assigned to Broadcom
  • Patent number: 6864723
    Abstract: A charge pump circuit includes a high-swing transconductance amplifier. A high input swing transconductance is provided in a negative feedback loop of the charge pump circuit without an abrupt change in transconductance. The high-swing transconductance amplifier includes a transconductance cell and high-swing circuitry. The transconductance cell includes a current supply transistor, which provides current for transconductance while input voltages are within the operational range for the transconductance cell. When the input voltages increase so as to be outside of the operational range, the current source transistor enters into triode region of operation, and provides reduced current. The high-swing circuitry supplies the current in this case so that abrupt change in transconductance does not occur.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventor: Ka Lun Choi
  • Patent number: 6865382
    Abstract: A mixer includes a reference current source, a programmable gain RF transconductance section or an RF transconductance section, switching quad native transistors or switching quad transistors, and a folded-cascoded common mode output section or an output section. When the mixer included the programmable gain RF transconductance section, the gain of the mixer is adjustable. When the mixer includes the switching quad native transistors, flicker noise of the mixer is reduced. When the mixer includes the folded-cascoded common mode output section, the mixer operates reliably from low supply voltages.
    Type: Grant
    Filed: January 7, 2002
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corp.
    Inventor: Arya Reza Behzad
  • Patent number: 6864812
    Abstract: Disclosed herein is a method and system to reduce the area and power dissipation in digital filters or multipliers. Compared to radix-4 Booth coding the proposed method reduces the number of partial products by one, if the input signal has certain limits on its range. One exemplary application is echo cancellation in a fill duplex pulse amplitude modulation system with 10 levels (PAM-10). Echo cancellation may be achieved by calculating a digital replica of the echo from the transmission channel. The replica signal may be calculated in a finite impulse response (FIR) filter, which multiplies the transmitted signal with estimates of the echo coefficients of the transmission channel. The replica signal may be subtracted from the received signal to create an echo-free receive signal. The disclosed method may reduce the number of partial products between the PAM-10 transmit signal and each echo coefficient from three, when radix-4 Booth coding is used, to two.
    Type: Grant
    Filed: February 5, 2004
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventor: Christian Lutkemeyer
  • Patent number: 6864819
    Abstract: A filter structure used with a dynamic element matching encoder for a sigma-delta digital-to-analog converter is presented. A sampled input sequence having undesired frequency tones is divided into even and odd data sub-sequences. Each of the sub-sequences is processed by a dynamic element matching encoder, with a transfer function H(z?1). The resulting processed sub-sequences are combined into an output sequence. The undesired frequency tones are substantially reduced in the output sequence.
    Type: Grant
    Filed: February 25, 2004
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventor: Minsheng Wang
  • Patent number: 6865381
    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: March 17, 2003
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventors: Pieter Vorenkamp, Klaas Bult, Frank Carr
  • Patent number: 6864752
    Abstract: A phase lock loop with multiple divider paths is presented herein. The phase lock loop can be used to provide a wide range of frequencies. The phase lock loop can also be used as a portion of a clock multiplier unit or a clock data and recovery unit.
    Type: Grant
    Filed: May 22, 2003
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventors: Mario Caresosa, Namik Kocaman, Afshin Momtaz
  • Patent number: 6864558
    Abstract: An improved cell layout for a C3MOS circuit with inductive broadbanding positions the inductor at a distance from the active region to improve isolation and aligns the edges of the resistor, inductor, and transistor regions near the common edge of adjacent cells to decrease the length of the cell-to-cell interconnect lines.
    Type: Grant
    Filed: May 17, 2001
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventors: Afshin D. Momtaz, Michael M. Green
  • Patent number: 6864737
    Abstract: Methods and systems for limiting power supply and ground bounce enables control of the output current drive dependent on the changes in supply (VDD and GND) levels. This is made possible by making the gate drive of the output driver PMOS and NMOS dependent on the VDD and GND swings. When the VDD or GND increases above normal operating levels, the gate drive of the output driver PMOS is reduced and when the GND or VDD reduces below normal operating levels, the gate drive of the output driver NMOS is reduced. This leads to reduced current flow between the supplies and the pad thereby reducing the VDD and GND bounce problem.
    Type: Grant
    Filed: June 14, 2004
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventor: Janardhanan S. Ajit
  • Patent number: 6865633
    Abstract: A system includes two or more agents and a distributed arbitration scheme for the bus to which the agents are connected. Thus, an arbiter corresponding to each agent is provided. The arbiters are reset using a first reset signal, while the agents are reset using a separate reset signal or signals. The arbiters are concurrently released from reset when the first reset signal is deasserted, and may have a consistent reset state to provide for synchronization of the arbiters. The agents may be independently released from reset by the separate reset signals. Accordingly, the arbiters may be synchronized and may remain synchronized even if the corresponding agents are released from reset at different times, or are temporarily held in reset for any reason.
    Type: Grant
    Filed: August 13, 2003
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventors: Joseph B. Rowlands, David L. Anderson, James Y. Cho
  • Patent number: 6865234
    Abstract: A method and a system for compensating for a permutation of L pairs of cable such that the compensation is localized in a trellis decoder of a receiver. The L pairs of cable correspond to L dimensions of a trellis code associated with the trellis decoder. The trellis code includes a plurality of code-subsets. The permutation of the L pairs of cable is determined. A plurality of sets of swap indicators based on the permutation of the L pairs of cable is generated. Each of the sets of swap indicators corresponds to one of the code-subsets. The code-subsets are remapped based on the corresponding sets of swap indicators.
    Type: Grant
    Filed: January 20, 2000
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventor: Oscar E. Agazzi
  • Patent number: 6864721
    Abstract: A decode circuit for selecting one of a plurality of output lines in dependence on the status of a plurality of input lines, the circuit comprising: a first decode arrangement comprising: a first decode node; first precharging circuitry for charging the first decode node to a charging potential; first discharging circuitry comprising a plurality of switching means each operable in dependence on the status of a respective one of the input lines to couple the first decode node to a discharging potential; and first selection circuitry coupled to a respective one of the output lines and operable in response to a first enable signal to select that output line if the first decode node has not discharged; and a second decode arrangement comprising: a second decode node; second precharging circuitry for charging the second decode node to a charging potential; second discharging circuitry comprising a plurality of switching means each operable in dependence on the status of a respective one of the input lines to coupl
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: March 8, 2005
    Assignee: Broadcom Corporation
    Inventor: Robert Beat
  • Publication number: 20050046471
    Abstract: Methods and apparatus for improving the current matching within current mirror circuits in applications such as low voltage integrated circuits. Embodiments of the present invention attempt to maintain the proper current ratio between reference and output supplies by adjusting the reference output of the current mirror. An existing reference voltage on the output side of the mirror can be used or a reference voltage can be created to be used for the voltage regulation of the reference side of the current mirror.
    Type: Application
    Filed: September 30, 2004
    Publication date: March 3, 2005
    Applicant: Broadcom Corporation
    Inventors: Arya Behzad, Frank Singor
  • Patent number: 6862448
    Abstract: A token-based receiver diversity processing is described. In one embodiment, a receiver diversity comprises repeaters receiving wirelessly transmitted packets from a mobile station, and one of the repeaters forwarding packets of the wirelessly transmitted packets to a switch if the one repeater is currently assigned to forward packets from the mobile station based on an indicator assigned prior to the wirelessly transmitted packets being sent.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: March 1, 2005
    Assignee: Broadcom Corporation
    Inventor: Harry Bims
  • Patent number: 6862230
    Abstract: The present invention relates to a system and method adapted to increase memory cell and memory architecture design yield. The present invention includes memory architecture having a decoder and a multi-bank memory. The decoder is adapted to decode addresses. The multi-bank memory interacts with the decoder, wherein the multi-bank memory includes at least one output data bit adapted to complete a word for a failing bank in the multi-bank memory.
    Type: Grant
    Filed: June 21, 2002
    Date of Patent: March 1, 2005
    Assignee: Broadcom Corporation
    Inventors: Gil I. Winograd, Esin Terzioglu
  • Patent number: 6861834
    Abstract: A system for measuring power of a circuit on a printed circuit board (PCB) including first and second circuits, a power strip, a power plane, and a calibration strip. The power strip is connected to the power plane to the first circuit, is embedded in the PCB during the manufacturing process, and also has at least two vias for measuring a voltage drop. The calibration strip is also embedded in the PCB during the manufacturing process and has at least two vias for measuring a voltage drop. The second circuit is configured to measure a voltage drop across the power strip as a first voltage and a voltage drop across the calibration strip as a second voltage, and to calculate the power being fed to the first circuit based on the first voltage and the second voltage.
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: March 1, 2005
    Assignee: Broadcom Corporation
    Inventors: James M. Kronrod, James J. Freeman, Kelly Coffey
  • Patent number: 6862161
    Abstract: The present invention relates to electrostatic discharge (ESD) protection and, more particularly, to methods and systems for improving response times of ESD triggering and clamping circuitry. An ESD protection circuit protects ESD circuitry from direct current (DC) voltage stress during normal operations by reducing terminal pad voltage level. A frequency bypass circuit implemented across an ESD protection circuit essentially acts as a short circuit during ESD events and essentially acts as an open circuit during normal operations. A frequency bypass circuit implemented in conjunction with an ESD protection circuit enables ESD triggering and clamping circuitry to react to ESD events without undue delay. Unlike an ESD protection circuit, a frequency bypass circuit does not result in substantial voltage reduction across its terminals. In an embodiment, the frequency bypass circuit includes one or more capacitors.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: March 1, 2005
    Assignee: Broadcom Corporation
    Inventor: Agnes Woo
  • Patent number: 6862353
    Abstract: A system and method is provided for supplying power over a home phone line network in a manner that is interoperable with other voice and data services operating on the same network. The system includes a power source coupled to the home phone line network. The power source includes an AC signal generator that generates an AC signal at a selected frequency. The power source also includes a band pass filter for removing unwanted harmonics from the AC signal, thereby generating a filtered AC signal for powering one or more devices on the home phone line network. One or more devices attached to the home phone line network, such as a telephone adapter or telephone, receives the filtered AC signal. Each device comprises a second band pass filter and an AC/DC converter. The second band pass filter passes the filtered AC signal to the AC/DC converter and prevents the introduction of undesired harmonics onto the home phone line network from the AC/DC converter.
    Type: Grant
    Filed: April 24, 2001
    Date of Patent: March 1, 2005
    Assignee: Broadcom Corporation
    Inventors: Theodore F. Rabenko, Charles G. Wier, Steven L. Caine, John H. Gleiter, Kevin L. Miller
  • Patent number: 6861750
    Abstract: Electrically, thermally and mechanically enhanced ball grid array (BGA) packages are described. An IC die is mounted to a first surface of a first stiffener. A peripheral edge portion of a second surface of the first stiffener is attached to a first surface of a second stiffener to cover an opening through the second stiffener that is open at the first surface and a second surface of the second stiffener. The second surface of the second stiffener is attached to a first surface of a substantially planar substrate that has a plurality of contact pads on the first surface of the substrate. The plurality of contact pads are electrically connected through the substrate to a plurality of solder ball pads on a second surface of the substrate.
    Type: Grant
    Filed: October 31, 2002
    Date of Patent: March 1, 2005
    Assignee: Broadcom Corporation
    Inventors: Sam Ziqun Zhao, Reza-ur Rahman Khan
  • Patent number: 6862444
    Abstract: A process of billing for access to and use of a wireless hotspot by a portable device is disclosed. A signal from the wireless hotspot is detected and access to the wireless hotspot is requested. The portable device awaits reply to the access request from the wireless hotspot and supplies account information to an access providing entity. Next, the portable device awaits a billing authorization from the access providing entity and, thereafter, data is exchanged with the wireless hotspot by the portable device when a billing authorized is received from the access providing entity. The account information is used to keep track of charges accrued through the access to and use of the wireless hotspot by the portable device.
    Type: Grant
    Filed: December 10, 2002
    Date of Patent: March 1, 2005
    Assignee: Broadcom Corporation
    Inventors: Jeyhan Karaoguz, Nambi Seshadri
  • Patent number: 6862438
    Abstract: A method and apparatus for dynamically controlling a programmable gain amplifier (PGA) to provide a plurality of gain steps thereby providing automatic gain control (AGC) in a receiver intermediate frequency (IF) stage comprising a succession of operational amplifiers wherein at least one is for providing fine gain control and wherein the gain of each fine gain amplifier is controlled by the resistance ratios of a plurality of selectively biased MOSFETs. In one embodiment of the invention, three coarse amplifiers are provided, each having a gain of either 0 dB or 12 dB based on the value of a two-state signal provided to each amplifier gain control input. A single fine gain amplifier has a gain of 0 dB, 3 dB, 6 dB or 9 dB based on the binary value of the two-bit signal provided to the amplifier. The combination of three coarse gain amplifiers and one fine gain amplifier provides for a total gain of 45 dB in 3 dB steps in the described embodiment of the invention.
    Type: Grant
    Filed: May 3, 2002
    Date of Patent: March 1, 2005
    Assignee: Broadcom Corporation
    Inventor: Hooman Darabi
  • Patent number: 4749417
    Abstract: A process for improving the corrosion resistance of an iron or steel part having a phosphate conversion coating, said method comprising contact of said part with a solution containing ions selected from the group of cobalt ions and nickel ions. Preferably, the solution also contains stannous ions. Contact may be by immersion or spraying.
    Type: Grant
    Filed: April 3, 1987
    Date of Patent: June 7, 1988
    Assignee: The Lea Manufacturing Company
    Inventors: James N. Tuttle, Jr., Olyn P. Jaboin