Patents Assigned to Broadcom
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Patent number: 6803829Abstract: An integrated VCO having an improved tuning range over process and temperature variations. There is therefore provided in a present embodiment of the invention an integrated VCO. The VCO comprises, a substrate, a VCO tuning control circuit responsive to a VCO state variable that is disposed upon the substrate, and a VCO disposed upon the substrate, having a tuning control voltage input falling within a VCO tuning range for adjusting a VCO frequency output, and having its tuning range adjusted by the tuning control circuit in response to the VCO state variable.Type: GrantFiled: June 17, 2002Date of Patent: October 12, 2004Assignee: Broadcom CorporationInventors: Ralph Duncan, Tom W. Kwan
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Patent number: 6804304Abstract: A power efficient and reduced electromagnetic interference (EMI) emissions multi-transmitter system for unshielded twisted pair (UTP) data communication applications. For each transmitter, digital transmit data is converted to a current-mode differential signal analog waveform by a digital-to-analog converter (DAC). The output current from each DAC is used to generate the required transmit voltage on the respective UTP line. Timing circuitry staggers the time base of each transmitter to reduce the aggregate EMI emissions of the multi-transmitter system.Type: GrantFiled: October 29, 1999Date of Patent: October 12, 2004Assignee: Broadcom CorporationInventor: Kevin T. Chan
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Patent number: 6804772Abstract: A microprocessor memory architecture including a read-only memory (ROM) with programmed microcode and a random access memory (RAM) capable of storing microcode and one or more data bits used for the selection of corresponding ROM or RAM microcode for execution. A multiplexer receives input signals from both the ROM microcode and RAM microcode, and a control signal which is one or more RAM data bits is used to select from the RAM or ROM microcode inputs for further execution by the microprocessor.Type: GrantFiled: March 21, 2001Date of Patent: October 12, 2004Assignee: Broadcom CorporationInventors: Sherman Lee, Vivian Y. Chou, John H. Lin
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Patent number: 6803828Abstract: A detector circuit for determining whether synchronization lock has been optimally achieved in feedback-type control systems. The detector circuit evaluates an error signal developed by a phase/frequency detector and compares the absolute magnitude of the error signal to a first threshold signal corresponding to a magnitude metric. When the value of the error signal is less than the magnitude threshold value, an event signal initiates a time interval counter which continues counting so long as the error signal remains below the magnitude threshold value. The time interval counter continues until it counts to a second threshold value corresponding to a timing metric. At this point, synchronization lock is declared.Type: GrantFiled: May 9, 2003Date of Patent: October 12, 2004Assignee: Broadcom CorporationInventors: Loke Kun Tan, Farzad Etemadi, Denny Yuen, Shauhyurn Tsai
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Patent number: 6804251Abstract: A multi-source data multiplexing system that accepts information packets from a plurality of signal sources, evaluates the relative efficiencies of data transmission, and transmits the information packets in provided grant regions for maximum efficiency. The multi-source data multiplexing system may accept any form of information packet from any form of signal source. The system receives a grant region, typically comprising a transmission time on a data channel, and inserts a information packet into the grant region. The actual information packet placed in the grant region may be one other than the packet for which the grant region was intended. Further, the multi-source data multiplexing system may fragment an information packet and transmit only a portion of the information packet in the grant region.Type: GrantFiled: October 27, 1999Date of Patent: October 12, 2004Assignee: Broadcom CorporationInventors: John Limb, Daniel Howard, Dolors Sala, Richard Protus, Ajay Chandra V. Gummalla
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Patent number: 6804194Abstract: A network switch for network communications includes a first data port interface which supports a plurality of data ports which transmit and receive data at a first data rate. A second data port interface is provided; the second data port interface supports a plurality of data ports transmitting and receiving data at a second data rate. A CPU interface is provided, with the CPU interface configured to communicate with a CPU. An internal memory is provided, and communicates with the first data port interface and the second data port interface. A memory management unit is provided, and includes an external memory interface for communicating data from at least one of the first data port interface and the second data port interface and an external memory. A communication channel is provided, with the communication channel communicating data and messaging information between the at least one first data port interface, the at least one second data port interface, the internal memory, and the memory management unit.Type: GrantFiled: August 21, 2000Date of Patent: October 12, 2004Assignee: Broadcom CorporationInventors: Shiri Kadambi, Shekhar Ambe
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Patent number: 6803306Abstract: A metal-insulator-metal (MIM) capacitor is made according to a copper dual-damascene process. A first copper or copper alloy metal layer if formed on a substrate. A portion of the first metal layer is utilized as the lower plate of the MIM capacitor. An etch stop dielectric layer is used during etching of subsequent layers. A portion of an etch stop layer is not removed and is utilized as the insulator for the MIM capacitor. A second copper or copper alloy metal layer is later formed on the substrate. A portion of the second metal layer is utilized as the upper plate of the MIM capacitor.Type: GrantFiled: January 4, 2001Date of Patent: October 12, 2004Assignee: Broadcom CorporationInventor: Liming Tsau
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Publication number: 20040196897Abstract: A system for reducing the complexity of an adaptive decision feedback equalizer, for use in connection with a dual-mode QAM/VSB receiver system is disclosed. QAM and VSB symbols, which are expressed in two's compliment notation, include an extra bit required to compensate for a fixed offset term introduced by the two's compliment numbering system. A decision feedback equalizer includes a decision feedback filter section which operates on symbolic decisions represented by a wordlength which excludes the added bit representing the offset. The vestigal word is convolved with the decision feedback filter's coefficients, while a DC component, corresponding to the excluded bit, is convolved with the same coefficient values in a correction filter. The two values are summed to provide an ISI compensation signal at the input of a decision device such as a slicer. A DC component representing a pilot tone in VSB transmission systems also introduces a DC component, and additional bits, to a VSB wordlength.Type: ApplicationFiled: April 23, 2004Publication date: October 7, 2004Applicant: Broadcom CorporationInventors: Loke Kun Tan, Tian-Min Liu, Hing "Ada" T. Hung
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Publication number: 20040196100Abstract: An operational amplifier includes a first stage with a first differential transistor pair inputting a differential input signal at their gates, a first tail current source transistor connected to sources of the first differential transistor pair, and a load transistor pair connected in series with the drain of first differential transistor pair. An input stage includes a second differential transistor pair connected to respective drains of the first differential transistor pair at their gates, and a second tail current transistor connected to sources of the differential transistor pair. An output stage outputs a signal corresponding to the differential input signal.Type: ApplicationFiled: April 14, 2004Publication date: October 7, 2004Applicant: Broadcom CorporationInventors: Eric B. Blecker, Sumant Ranganathan
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Publication number: 20040198250Abstract: A linear high powered integrated circuit transmitter includes an up-conversion module, a plurality of power amplifiers, balanced integrated circuit coupling, and a combining circuit. The up-conversion module is operably coupled to produce a differential up-converted signal by mixing one or more local oscillations with a low intermediate frequency (IF) signal. The balanced integrated circuit coupling couples the plurality of power amplifiers to the up-conversion module such that the power amplifiers amplify the up-converted signal to produce a plurality of amplified radio frequency (RF) signals. The combining circuit is operably coupled to combine the plurality of amplified RF signals to produce a transmit RF signal.Type: ApplicationFiled: July 23, 2002Publication date: October 7, 2004Applicant: Broadcom Corporation a, California CorporationInventor: Shahla Khorram
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Publication number: 20040196361Abstract: An electronic, programmable filter is disclosed which selectively removes interference, noise or distortion components from a frequency band without perturbing any of the other signals of the band. An input frequency band such as a television channel spectrum is initially demodulated to baseband and applied to the input of the filter. The baseband spectrum is combined in a complex mixer with a synthesized frequency signal that shifts the spectrum a characteristic amount, in the frequency domain, so as to position an interference component in the region about DC. Once shifted, the frequency components about DC are removed by DC canceler circuit and the resulting spectrum is mixed with a subsequent synthesized frequency signal which shifts the spectrum back to its original representation and baseband. The frequency signals are developed by a programmable frequency synthesizer which a user may program with an intelligence signal that defines the frequency location of an interference signal within the spectrum.Type: ApplicationFiled: April 16, 2004Publication date: October 7, 2004Applicant: Broadcom CorporationInventors: Tian-Min Liu, Loke Kun Tan, Steven T. Jaffe, Robert A. Hawley
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Publication number: 20040198290Abstract: A linear fractional-N synthesizer includes phase and frequency detection module, a charge pump circuit, a loop filter, a voltage controlled oscillator, and a fractional-N divider. The phase and frequency detection module is operably coupled to produce a charge up signal, a charge down signal, or an off signal based on a phase difference and/or a frequency difference between a reference oscillation and a feedback oscillation. The charge pump circuit is operably coupled to produce a positive current when the charge up signal is received, a negative current when the charge down signal is received, and a non-zero offset current when the off signal is received. The charge pump includes a resistor and a control module. The resistor provides the non-zero offset current and the control module maintains the non-zero offset current at a substantially constant value.Type: ApplicationFiled: April 3, 2003Publication date: October 7, 2004Applicant: Broadcom Corporation, a California CorporationInventor: Hung-Ming Chien
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Publication number: 20040196857Abstract: A method of providing for synchronizing one or more synchronous terminals with one or more synchronous endpoints, each synchronous terminal and each synchronous endpoint having an asynchronous communications network coupled between at least one synchronous terminal and at least one synchronous endpoint. A synchronization protocol is established between a synchronous terminal and a synchronous end point by providing a gateway between the asynchronous communications network and the synchronous end point, the gateway communicating with the synchronous terminal over the asynchronous communications network in accordance with the synchronization protocol. The synchronization protocol includes sending a message from the gateway to the synchronous terminal, the message containing a timestamp identifying a clock associated with the synchronous end point.Type: ApplicationFiled: April 21, 2004Publication date: October 7, 2004Applicant: Broadcom CorporationInventors: John T. Holloway, Matthew James Fischer, Jason Alexander Trachewsky
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Publication number: 20040196106Abstract: A lock-detect circuit is configured to detect whether an incoming signal has acquired a lock to a reference signal using a first frequency detect window and to detect whether the incoming signal has lost a previously acquired a lock to the reference signal using a second frequency detect window different from the first frequency detect window. The two signals are applied to two different down-counters that are first synchronized before initiating their count-downs. If the offset between the counts of the two counters is less than the first frequency detect window, the incoming signal is detected as having acquired a lock to the reference signal. If the offset between the counts of the two counters is greater than the second frequency detect window, the incoming signal is detected as having lost its previously acquired lock to the reference signal.Type: ApplicationFiled: April 22, 2004Publication date: October 7, 2004Applicant: Broadcom CorporationInventor: David Kyong-sik Chung
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System and method for measuring the thickness or temperature of a circuit in a printed circuit board
Publication number: 20040196056Abstract: System for measuring a thickness of a circuit component on a printed circuit board (PCB). The system includes a first circuit, a power plane, a power strip, a calibration strip, a temperature sensor, and a second circuit. The power plane is coupled to the first circuit. The power strip is for providing power to the power plane and is disposed in the PCB connected to the power plane. The power strip has at least two vias. The calibration strip has a predetermined width and is disposed in said PCB. The calibration strip has at least two vias for measuring a voltage drop. The temperature sensor is coupled to the calibration strip and configured to measuring a temperature of the calibration strip. The second circuit is coupled to the temperature sensor and configured to determine the thickness of the calibration strip based on at least the temperature of the calibration strip.Type: ApplicationFiled: March 22, 2004Publication date: October 7, 2004Applicant: Broadcom CorporationInventor: James M. Kronrod -
Publication number: 20040198284Abstract: A digital high frequency power detection circuit includes a peak detecting circuit and a peak computing circuit. The peak detecting circuit is operably coupled to detect a peak value of a high frequency signal and includes an amplifier, transistor, and capacitor. The amplifier has a 1st input, 2nd input and an output, where the 1st input is operably coupled to receive the high frequency signal. The transistor has a gate, a drain, and a source, where the gate is coupled to the output of the amplifier, the source is coupled to a supply voltage, and the drain is coupled to the 2nd input of the amplifier. The capacitor is operably coupled to the drain of the transistor and to a reference potential. The voltage imposed across the capacitor represents the peak value of the high frequency signal. The peak computing circuit is operably coupled to generate a digital peak value from the peak value.Type: ApplicationFiled: July 23, 2002Publication date: October 7, 2004Applicant: Broadcom CorporationInventor: Shahla Khorram
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Patent number: 6801092Abstract: A phase locked loop includes a difference detector, a loop filter, a controlled oscillation module, and a frequency translation module. The difference detector is operably coupled to determine a difference signal based on phase and/or frequency differences between a feedback oscillation and a reference oscillation. The loop filter is operably coupled to generate a control signal from the difference signal. The controlled oscillation module is operably coupled to produce, in accordance with an adjustable operating parameter, an output oscillation based on the controlled signal. The adjustable operating parameter is set based on desired operating conditions of the phase locked loop such that false locking of the phase locked loop is substantially avoided. The frequency translation module is operably coupled to produce the feedback oscillation from the output oscillation based on a frequency translation rate.Type: GrantFiled: April 8, 2003Date of Patent: October 5, 2004Assignee: Broadcom Corp.Inventor: Shervin Moloudi
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Patent number: 6801577Abstract: A transmitter portion and a receiver portion are implemented within various devices that communicate using low voltage swing pads communicatively coupled via a trace. The transmitter portion of one device generates a current signal that is pushed/pulled to a low voltage swing pad and is then passed across the trace to another low voltage swing pad. The transmitter portion includes a current driver that outputs the current signal to the low voltage swing pads, and the receiver portion includes a trans-impedance amplifier that transforms the received current signal into a voltage signal. The low voltage swing pad driver and receiver generates a relatively low voltage swing when compared to CMOS full-scale voltage swings thereby significantly reducing the possibility of introducing any noise and/or distortion of data that is communicated via the interface.Type: GrantFiled: July 16, 2002Date of Patent: October 5, 2004Assignee: Broadcom CorporationInventors: Sumant Ranganathan, Tom W. Kwan
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Patent number: 6801761Abstract: A programmable mixer includes a 1st mixing stage, a 2nd mixing stage, a coupling element, and a compensation module. The 1st mixing stage is operably coupled to mix one leg of a differential input signal with a differential local oscillation. The 2nd mixing stage is operably coupled to mix the other leg of the differential input with the differential local oscillation. The coupling element couples the 1st and 2nd mixing stages together. The compensation module is operably coupled to the 1st mixing stage and/or the 2nd mixing stage to modify the operational characteristics (e.g., current, impedance, gain, et cetera) of the 1st and/or 2nd mixing stages based on a control signal.Type: GrantFiled: February 15, 2002Date of Patent: October 5, 2004Assignee: Broadcom Corp.Inventor: Shahla Khorram
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Patent number: 6801085Abstract: A system is provided for activating gain stages in an amplification module. The system includes an amplification module including a first group of amplifiers. Inverting output ports of each of the first group of amplifiers are coupled to a module inverting output terminal, and non-inverting output ports are coupled to a module non-inverting output terminal. A divider network is provided and is coupled to the input ports of the first group of amplifiers. A second group of amplifiers is also provided. Each amplifier of the second group corresponds to one of the amplifiers in the first group, has an inverting input port coupled to the second module inverting input terminal and to output ports of the divider network, and a non-inverting input port coupled to the second non-inverting input terminal.Type: GrantFiled: July 31, 2003Date of Patent: October 5, 2004Assignee: Broadcom CorporationInventors: Adel Fanous, Leonard Dauphinee, Lawrence M. Burns, Donald McMullin