Abstract: A method for increasing upstream bandwidth per cable modem user in a cable communications system that includes a cable modem termination system (CMTS) and a plurality of cable modems is provided. The method permits a cable modem to transmit data to the CMTS on multiple upstream channels simultaneously using a technique called “channel bonding.” Channel bonding allows smaller bandwidth upstream channels to be bonded together to create a larger bandwidth pipe.
Type:
Application
Filed:
December 12, 2005
Publication date:
June 15, 2006
Applicant:
Broadcom Corporation
Inventors:
Lisa Denney, Niki Pantelias, A. Hollums, Victor Hou, John Horton, David Pullen
Abstract: An ESD device includes a low doped well connected to a first contact and a diffusion area connected to a second contact. A substrate between the low doped well and the diffusion area has a dopant polarity that is opposite a dopant polarity of the low doped well and the diffusion area. A distance between the low doped well and the diffusion area determines a triggering voltage of the ESD device. A depletion region is formed between the low doped well and the substrate when a reverse bias voltage is applied to the ESD device. A current discharging path is formed between the first contact and the second contact when the depletion region comes in to contact with the diffusion area. The substrate is biased by a connection to the second contact. Alternatively, an additional diffusion area with the same dopant polarity, connected to a third contact, biases the substrate.
Abstract: A digital modulator includes a quantizer and a mapper. The quantizer converts a dithered signal value to a voltage. The mapper provides a modulated signal based on the voltage received from the quantizer. The mapper may maintain a substantially identical average centroid for modulated signals provided by the mapper. In an aspect, the mapper is included in a feedback of the digital modulator. The digital modulator may include any number of mappers. For example, a mode selection switch may select one of a plurality of mappers to map a voltage level received from the quantizer to a respective digital sequence.
Abstract: A method for increasing upstream bandwidth per cable modem user in a cable communications system that includes a cable modem termination system (CMTS) and a plurality of cable modems is provided. The method permits a cable modem to transmit data to the CMTS on multiple upstream channels simultaneously using a technique called “channel bonding.” Channel bonding allows smaller bandwidth upstream channels to be bonded together to create a larger bandwidth pipe.
Type:
Application
Filed:
December 12, 2005
Publication date:
June 15, 2006
Applicant:
Broadcom Corporation
Inventors:
Lisa Denney, Niki Pantelias, A. Hollums, Victor Hou, John Horton, David Pullen
Abstract: A method for increasing upstream bandwidth per cable modem user in a cable communications system that includes a cable modem termination system (CMTS) and a plurality of cable modems is provided. The method permits a cable modem to transmit data to the CMTS on multiple upstream channels simultaneously using a technique called “channel bonding.” Channel bonding allows smaller bandwidth upstream channels to be bonded together to create a larger bandwidth pipe.
Type:
Application
Filed:
December 12, 2005
Publication date:
June 15, 2006
Applicant:
Broadcom Corporation
Inventors:
Lisa Denney, Niki Pantelias, A. Hollums, Victor Hou, John Horton, David Pullen
Abstract: The variable gain amplifier includes a forward path that provides the amplifier variable gain, and a feedback path. The feedback path uses a switch that is turned on at low gain levels. The switch taps into the feedback resistor, shunting it to signal-ground and eliminating the feedback mechanism. This ensures that the input impedance seen at the input port does not grow excessively, using part of the feedback resistor as a passive termination at low gain levels. In this way variable gain ranges in excess of 30 dB can be achieved.
Abstract: Methods and apparatus are provided for efficiently normalizing and denormalizing data for cryptography processing. The normalization and denormalization techniques can be applied in the context of a cryptography accelerator coupled with a processor. Hardware normalization techniques are applied to data prior to cryptography processing. Context circuitry tracks the shift amount used for normalization. After cryptography processing, the processed data is denormalized using the shift amount tracked by the context circuitry.
Abstract: Classification of packets into flows is an inherent operation performed by networks that support enhanced services. To support multiple-dimensional packet classification, a packet classification system is provided to select representative bits from a packet to look up a set of rules. The per-flow classification works with a large set of rules, where each rule comprises of multiple fields and also allows fast dynamic variation in the rule set. A lookup process includes a simple and finite set of instructions that can be efficiently implemented as pipelined hardware and support very high packet arrival rates.
Type:
Grant
Filed:
January 18, 2002
Date of Patent:
June 13, 2006
Assignee:
Broadcom Corporation
Inventors:
Shashidhar Merugu, Ajay Chandra V Gummalla, Dolors Sala
Abstract: A method and apparatus are disclosed for easily reconfiguring a scan chain test of a subset of scan blocks within a digital integrated circuit chip. To mitigate timing violations in the scan test of scan chains, alternative embodiments to implement a transfer of scan data to a next scan block are implemented.
Abstract: Methods and systems for increasing gain for an electric circuit may include receiving an input differential signal at a first configured pair of transistors and a second configured pair of transistors. The first and second configured pair of transistors may be inductively loaded. The first configured pair of transistors may be self-biased via the inductive loading. DC current may be generated via the second configured pair of transistors. The first and/or the second configured pair of transistors may be configured as input transconductors. A pair of inductors may be configured for the inductive loading and the configured pair of inductors may be tapped for the self-biasing. If the first configured pair of transistors comprises NMOS transistors, then the second configured pair of transistors may comprise PMOS transistors.
Abstract: A network controller having a multiprotocol bus interface adapter coupled between a communication network and a computer bus, the adapter including a predictive time base generator; and a management bus controller adapted to monitor and manage preselected components coupled with one of the communication network and the computer bus. The management bus controller is adapted to employ an Alert Standard Format (ASF) specification protocol, a System Management Bus (SMBus) specification protocol, an Intelligent Platform Management Interface (IPMI) specification protocol, a Simple Network Management Protocol (SNMP), or a combination thereof. The network controller also includes a 10/100/1000BASE-T IEEE Std. 802.
Type:
Grant
Filed:
April 24, 2002
Date of Patent:
June 13, 2006
Assignee:
Broadcom Corporation
Inventors:
Steven B. Lindsay, Andrew SeungHo Hwang, Andrew M. Naylor, Michael Asker
Abstract: 16 QAM (Quadrature Amplitude Modulation) and 16 APSK (Asymmetric Phase Shift Keying) TTCM (Turbo Trellis Coded Modulation) with minimum bandwidth efficiency of 3 bit/s/Hz (bits per second per Hertz) using a rate 2/4 constituent encoder. Various encoder designs are presented that are operable to generate a signal whose modulation may vary as frequently as on a symbol by symbol basis while providing relatively very high throughput. Rate control sequences including RCs (Rate Controls), arranged in a period, govern the manner in which symbols of a signal are generated. The RCs correspond to various modulations that may each have a unique constellation and corresponding mapping. Different RCs may be included within a rate control sequence that correspond to 16 QAM, 16 APSK, QPSK (Quadrature Phase Shift Key), or even other modulation types. In addition, 1 or more uncoded bits may be used to generate the symbols of the coded signal.
Type:
Grant
Filed:
August 7, 2003
Date of Patent:
June 13, 2006
Assignee:
Broadcom Corporation
Inventors:
Ba-Zhong Shen, Kelly Brian Cameron, Hau Thien Tran
Abstract: A system is provided for correcting start-up deficiencies in an amplifier. The system includes a comparing device configured to (i) receive a second circuit node voltage and a reference voltage as inputs, (ii) compare the received second circuit node voltage and the reference voltage, and (iii) produce a compensating voltage signal based upon the comparison. Next, an active device has a control terminal connected to an output port of the comparing device and is configured to receive the compensating voltage signal. The active device also includes an output terminal connected to the control terminal of the second active device, and a common terminal connected to a first circuit node. Another active device has a control terminal connected to the output port of the comparing device and is configured to receive the compensating voltage signal. The other active device also has an output terminal connected to the control terminal of the first active device, and a common terminal connected to the first circuit node.
Abstract: A method and system for allocating an initial maintenance request (IMR) for an upstream channel in a communications system, wherein the communication system includes a headend and at least one remote device associated with the channel. A first propagation delay from the headend to the remote device having the greatest delay is determined. Likewise, a second propagation delay from the headend to the remote device experiencing the least delay is determined. The IMR is then defined to be shorter than the first propagation delay and at least as long as the difference between the two propagation delays. The starting point of the IMR is established by modifying the clock output of the headend. A modification value is added to the headend clock output. The modification value corresponds to a time interval that can be as long as the propagation delay from the headend to the remote having the shortest delay.
Abstract: Provided is a system and method for converting digital data audio data audio data that has a predetermined input sample rate, into an analog data signal. A system includes a digital to analog converter (DAC) including a digital processing portion configured to receive as an input the digital audio data and timing information, the timing information being representative of a time base of the input sample rate. The digital processing portion is similarly configured to digitally process the digital audio data and the timing information to produce serialized output data. The DAC also includes an analog processing portion configured to convert serialized data to an analog format. The digital processing portion operates in accordance with at least one clock having a corresponding clock rate wherein the corresponding clock rate is unrelated to the input sample rate.
Type:
Application
Filed:
January 31, 2006
Publication date:
June 8, 2006
Applicant:
Broadcom Corporation
Inventors:
Kevin Miller, Keith Klingler, Brian Schoner
Abstract: A high-speed serial data transceiver includes multiple receivers and transmitters for receiving and transmitting multiple analog, serial data signals at multi-gigabit-per-second data rates. Each receiver includes a timing recovery system for tracking a phase and a frequency of the serial data signal associated with the receiver. The timing recovery system includes a phase interpolator responsive to phase control signals and a set of reference signals having different predetermined phases. The phase interpolator derives a sampling signal, having an interpolated phase, to sample the serial data signal. The timing recovery system in each receiver independently phase-aligns and frequency synchronizes the sampling signal to the serial data signal associated with the receiver. A receiver can include multiple paths for sampling a received, serial data signal in accordance with multiple time-staggered sampling signals, each having an interpolated phase.
Type:
Grant
Filed:
April 30, 2001
Date of Patent:
June 6, 2006
Assignee:
Broadcom Corporation
Inventors:
Aaron W. Buchwald, Michael Le, Jurgen Van Engelen, Xicheng Jiang, Hui Wang, Howard A. Baumer, Avanindra Madisetti
Abstract: A logic circuit includes an interface and an error detection unit. The interface is configured to receive and transmit a data stream, wherein the data stream includes at least one of a variable length format packet or burst and a fixed length format packet or burst. The error detection unit is configured to detect an error detection code error when a misalignment occurs within the data stream by recursively calculating parity terms.
Abstract: Aspects of the invention for converting interlace formatted video to progressive scan video, may include a color edge detector block (306) adapted to determined edges in interlaced formatted video. A threshold and gain processor block (308) coupled to the color edge detector block (306) may be adapted to quantify a likelihood of motion for each pixel comprising at least a portion of the interlaced scanned video using a motion value. A binder block (310) coupled to the threshold and gain processor block (308) may be configured to combine the motion value for each component of a luminance and chrominance of each of the pixels. A resampler block (314) may be coupled to the binder to determine an actual pixel value. The resampler block (314) may include at least one of a vertical and a horizontal filter adapted to determine an actual value of each of the pixels in at least a portion of the interlaced scanned video.
Abstract: A graphics integrated circuit chip is used in a set-top box for controlling a television display. The graphics chip processes analog video input, digital video input, a graphics input and an audio input simultaneously. The chip includes a display engine that processes graphics images organized as windows. The system includes plurality of line buffers for receiving the graphics contents. The graphics contents are composited into each of the plurality of line buffers by blending the graphics contents with the existing contents of the line buffer until all of the graphics surfaces for the line have been composited.
Type:
Grant
Filed:
April 25, 2003
Date of Patent:
June 6, 2006
Assignee:
Broadcom Corporation
Inventors:
Alexander G. MacInnis, Chengfuh Jeffrey Tang, Xiaodong Xie, James T. Patterson, Greg A. Kranawetter
Abstract: A high precision charge pump used in a phase-lock-loop incorporating a phase/frequency detector is designed and constructed to substantially eliminate the effects of DC offset and glitch errors on the charge pump output current. The high precision charge pump is constructed of parallel current paths each having a central node which is, in turn, connected to a feedback element. The feedback element defines a feedback current which is applied to the charge pump so as to maintain the two central nodes at an equi-potential level and to maintain the value of the pump-down current exactly equal to the value of the pump-up current output by the device.