Patents by Inventor Aslamali A. Rafi

Aslamali A. Rafi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8145172
    Abstract: A receiver (400) includes a tracking bandpass filter (420) and a signal processing circuit (430-480). The tracking bandpass filter (420) has a first input for receiving a radio frequency (RF) signal, and an output, and includes a first portion (731) on a semiconductor die (730), and at least one inductor (721). The at least one inductor (721) is operatively coupled to the first portion of the tracking bandpass filter (420). The signal processing circuit (430-480) has an input coupled to the output of the tracking bandpass filter (420), and an output for providing a processed signal. The semiconductor die (730) and the at least one inductor (721) are integrated into a single multi-chip module (MCM) (710).
    Type: Grant
    Filed: November 25, 2008
    Date of Patent: March 27, 2012
    Assignee: Silicon Laboratories Inc.
    Inventors: Ramin Khoini-Poorfard, Alessandro Piovaccari, Aslamali A. Rafi, Mustafa H. Koroglu, David S. Trager
  • Publication number: 20120046007
    Abstract: In one embodiment, the present invention includes a mixer circuit to receive and generate a mixed signal from a radio frequency (RF) signal and a master clock signal, a switch stage coupled to an output of the mixer circuit to rotatingly switch the mixed signal to multiple gain stages coupled to the switch stage, and a combiner to combine an output of the gain stages.
    Type: Application
    Filed: October 31, 2011
    Publication date: February 23, 2012
    Inventor: Aslamali A. Rafi
  • Publication number: 20110316631
    Abstract: A low-noise amplifier (LNA) includes an input terminal for receiving an input signal, an output terminal for providing an output signal related to the input signal. The LNA further includes a first transistor having a first source coupled to the input terminal through the first capacitor, a first gate configured to receive a first direct current (DC) bias signal, and a first drain coupled to the output terminal. The LNA also includes a second transistor having a second source coupled to the input terminal through the second capacitor, a second gate configured to receive a second DC bias signal, and a second drain coupled to the output terminal.
    Type: Application
    Filed: June 28, 2010
    Publication date: December 29, 2011
    Applicant: SILICON LABORATORIES, INC.
    Inventor: Aslamali A. Rafi
  • Publication number: 20110317077
    Abstract: In one embodiment, the present invention is directed to an apparatus configured to perform channel filtering operations digitally, to reduce area and power consumption as compared to analog filtering. After passive filtering of downconverted analog baseband signals, the signals are provided to digitization circuitry to convert the filtered baseband signals into digital signals. Then a digital circuit, which may be implemented as a digital signal processor (DSP), may channel filter the digital signals and provide the filtered digital signals to conversion circuitry to convert the channel filtered digital signals back to analog signals.
    Type: Application
    Filed: June 28, 2010
    Publication date: December 29, 2011
    Inventors: Abdulkerim L. Coban, Aslamali A. Rafi
  • Publication number: 20110244820
    Abstract: An integrated wideband receiver includes first and second signal processing paths and a controller. The first signal processing path has an input, and an output for providing a first processed signal, and comprises a first tracking bandpass filter having a first integrated inductor. The second signal processing path has an input, and an output for providing a second processed signal, and comprises a second tracking bandpass filter having a second integrated inductor. The controller is for enabling one of the first and second signal processing paths corresponding to a selected channel of a radio frequency (RF) input signal to provide an output signal. The controller, the first integrated inductor, and said second integrated inductor are formed on a single integrated circuit chip.
    Type: Application
    Filed: June 15, 2011
    Publication date: October 6, 2011
    Inventors: Ramin Khoini-Poorfard, Alessandro Piovaccari, Aslamali A. Rafi, Mustafa H. Koroglu, David S. Trager, Abdulkerim L. Coban
  • Publication number: 20110235758
    Abstract: A receiver circuit includes an analog front-end and a digital processing unit. The analog front-end includes an input for receiving a radio frequency (RF) signal, a first control input for receiving a gain adjustment signal, a second control input for receiving a timing signal, and a signal output for providing a digital intermediate frequency (IF) signal. The analog front-end updates gains of a plurality of gain stages according to the gain adjustment signal and in synchronism with the timing signal. The digital processing unit is configured to produce at least one output signal derived from the digital IF signal. The digital processing unit includes a timing recovery circuit configured to generate the timing signal based on the digital IF signal to control timing of the updating gains of each of the plurality of adjustable gain stages.
    Type: Application
    Filed: May 28, 2010
    Publication date: September 29, 2011
    Applicant: SILICON LABORATORIES, INC.
    Inventors: Ramin Khoini-Poorfard, Alan F. Hendrickson, Alessandro Piovaccari, David S. Trager, Aslamali A. Rafi, Abdulkerim L. Coban, David Le Goff
  • Publication number: 20110201289
    Abstract: In one embodiment, the present invention includes a mixer circuit to receive and generate a mixed signal from a radio frequency (RF) signal and a master clock signal, a switch stage coupled to an output of the mixer circuit to rotatingly switch the mixed signal to multiple gain stages coupled to the switch stage, and a combiner to combine an output of the gain stages.
    Type: Application
    Filed: February 17, 2011
    Publication date: August 18, 2011
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari, Peter Vancorenland, Tyson Tuttle
  • Patent number: 7986926
    Abstract: A system includes a cellular radio and an FM transmitter that are fabricated in the same semiconductor. The FM transmitter includes at least one mixer, a filter and an antenna tuning network. The mixer(s) translate an intermediate carrier frequency of an input signal to generate a second signal that has an FM carrier frequency. The filter removes spectral energy from the second signal to generate a third signal. The antenna tuning network is separate from the filter and produces a fourth signal to drive an antenna in response to the third signal.
    Type: Grant
    Filed: September 27, 2006
    Date of Patent: July 26, 2011
    Assignee: Silicon Laboratories Inc.
    Inventors: Aslamali A. Rafi, Dan B. Kasha
  • Patent number: 7973603
    Abstract: A low-noise amplifier includes a first resistor that receives a first signal of a differential input signal, and a second resistor that receives a second signal of the differential input signal. The amplifier includes a first transconductance device coupled to the first resistor that provides a first signal of a differential output signal, and a second transconductance device coupled to the second resistor, that provides a second signal of the differential output signal. The receiver also includes a first capacitor coupled between the first resistor input and a control electrode on the second transconductance device, and a second capacitor coupled between the second resistor input and a control electrode on the first transconductance device. The low-noise amplifier can include additional gain stages.
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: July 5, 2011
    Assignee: Silicon Laboratories Inc.
    Inventors: Abhishek V. Kammula, Aslamali A. Rafi, George Tyson Tuttle
  • Publication number: 20110065411
    Abstract: In one embodiment, the present invention includes a method for receiving a radio frequency (RF) signal and mixing the RF signal with a master clock to obtain a mixed signal, cyclically rotating the mixed signal to each of N gain stages for at least one cycle of the master clock, and summing the outputs of the N gain stages to provide an output signal.
    Type: Application
    Filed: November 16, 2010
    Publication date: March 17, 2011
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Patent number: 7904035
    Abstract: A radio frequency (RF) communications device is provided. The RF communications device includes transmitter circuitry configured to generate a calibration signal on a signal line coupled to an antenna port in a calibration mode of operation and an RF output signal for broadcast across the antenna port subsequent to the calibration mode of operation, tuning circuitry coupled to the signal line and configured to receive the calibration signal, and a controller configured to adjust a signal level of the calibration signal generated by the transmitter circuitry and a tuning of the tuning circuitry during the calibration mode of operation. The transmitter circuitry, the tuning circuitry, and the controller are at least partially integrated on the same integrated circuit.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: March 8, 2011
    Assignee: Silicon Laboratories Inc.
    Inventors: Dan B. Kasha, Aslamali A. Rafi, Abhishek V. Kammula, Peter J. Vancorenland, George T. Tuttle
  • Publication number: 20100328542
    Abstract: A low-noise amplifier includes a first resistor that receives a first signal of a differential input signal, and a second resistor that receives a second signal of the differential input signal. The amplifier includes a first transconductance device coupled to the first resistor that provides a first signal of a differential output signal, and a second transconductance device coupled to the second resistor, that provides a second signal of the differential output signal. The receiver also includes a first capacitor coupled between the first resistor input and a control electrode on the second transconductance device, and a second capacitor coupled between the second resistor input and a control electrode on the first transconductance device. The low-noise amplifier can include additional gain stages.
    Type: Application
    Filed: June 26, 2009
    Publication date: December 30, 2010
    Applicant: SILICON LABORATORIES, INC.
    Inventors: Abhishek V. Kammula, Aslamali A. Rafi, George Tyson Tuttle
  • Publication number: 20100328546
    Abstract: In one embodiment, a set of tracking filters to be coupled between an amplifier and a mixer is provided. The tracking filters may be differently configured depending on band of operation. For example, a first set of the filters can be configured to maintain a substantially constant Q value across their operating bandwidth while a second set of the filters can be configured to maintain a substantially constant bandwidth across their operating bandwidth.
    Type: Application
    Filed: June 29, 2009
    Publication date: December 30, 2010
    Inventors: Aslamali A. Rafi, Chunyu Xin, Ruifeng Sun, Abhishek Kammula, Ramin Khoini-Poorfard, Alessandro Piovaccari, Peter J. Vancorenland
  • Patent number: 7860480
    Abstract: In one embodiment, the present invention includes a method for receiving a radio frequency (RF) signal and mixing the RF signal with a master clock to obtain a mixed signal, cyclically rotating the mixed signal to each of N gain stages for at least one cycle of the master clock, and summing the outputs of the N gain stages to provide an output signal.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: December 28, 2010
    Assignee: Silicon Laboratories Inc.
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Publication number: 20100267350
    Abstract: A communications device is provided. The communications device includes a first antenna port coupled to a signal line, transmitter circuitry coupled to the signal line and configured to broadcast a radio frequency (RF) output signal across the first antenna port, tuning circuitry coupled to the signal line, and a controller configured to adjust a tuning of the tuning circuitry. The first antenna port, the transmitter circuitry, the tuning circuitry, and the controller are at least partially integrated on the same integrated circuit.
    Type: Application
    Filed: June 28, 2010
    Publication date: October 21, 2010
    Applicant: SILICON LABORATORIES, INC.
    Inventors: Dan B. Kasha, Aslamali A. Rafi, Abhishek V. Kammula, Peter J. Vancorenland, George T. Tuttle
  • Publication number: 20100240335
    Abstract: In one embodiment, the present invention includes a mixer circuit to receive and generate a mixed signal from a radio frequency (RF) signal and a master clock signal, a switch stage coupled to an output of the mixer circuit to rotatingly switch the mixed signal to multiple gain stages coupled to the switch stage, and a combiner to combine an output of the gain stages.
    Type: Application
    Filed: June 4, 2010
    Publication date: September 23, 2010
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Publication number: 20100233987
    Abstract: In one embodiment, an apparatus includes mixer stages each coupled to receive a radio frequency (RF) signal from a corresponding tracking filter each configured for a band of frequencies. Each mixer stage is controllable to mix the RF signal with a divided master clock signal to obtain N multi-phase intermediate frequency (IF) signals, where N is programmable based upon a desired channel frequency. A load network having individual loads to be shared by the mixers can be coupled to the mixer stages, and a shared IF combiner may be coupled to the load network to weight and combine outputs of the load network to obtain a quadrature IF signal. The load network can include multiple loads each to be individually controlled to receive one of the multi-phase IF signals.
    Type: Application
    Filed: March 12, 2010
    Publication date: September 16, 2010
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Patent number: 7756504
    Abstract: In one embodiment, the present invention includes a mixer circuit to receive and generate a mixed signal from a radio frequency (RF) signal and a master clock signal, a switch stage coupled to an output of the mixer circuit to rotatingly switch the mixed signal to multiple gain stages coupled to the switch stage, and a combiner to combine an output of the gain stages.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: July 13, 2010
    Assignee: Silicon Laboratories Inc.
    Inventors: Aslamali A. Rafi, Alessandro Piovaccari
  • Patent number: 7747228
    Abstract: A communications device is provided. The communications device includes a first antenna port coupled to a signal line, transmitter circuitry coupled to the signal line and configured to broadcast a radio frequency (RF) output signal across the first antenna port, tuning circuitry coupled to the signal line, and a controller configured to adjust a tuning of the tuning circuitry. The first antenna port, the transmitter circuitry, the tuning circuitry, and the controller are at least partially integrated on the same integrated circuit.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: June 29, 2010
    Assignee: Silicon Laboratories, Inc.
    Inventors: Dan B. Kasha, Aslamali A. Rafi, Abhishek V. Kammula, Peter J. Vancorenland, George T. Tuttle
  • Patent number: 7738851
    Abstract: A technique includes providing a plurality of local oscillator signals such that each of the local oscillator signals has a different phase. The technique includes providing scaling units to scale the input signal pursuant to different scaling factors to generate scaled input signals. The scaling factors are selected on a periodic function of the phases. The technique also includes providing mixing circuits to mix the local oscillator signals with the scaled input signals to generate mixed signals and providing an adder to combine the mixed signals to generate an output signal.
    Type: Grant
    Filed: September 27, 2006
    Date of Patent: June 15, 2010
    Assignee: Silicon Laboratories Inc.
    Inventors: Daniel J. Cooley, Aslamali A. Rafi