In Series With Input Source Patents (Class 330/106)
  • Patent number: 8521105
    Abstract: A transmitter for transmitting a transmission signal is disclosed. The transmitter includes: a gain stage, for receiving an input signal and amplifying the input signal according to a gain to generate an amplified signal; and an output stage, coupled to the gain stage, for receiving a first reference voltage signal and the amplified signal and utilizing the first reference voltage signal to perform a predetermined operation on the amplified signal to generate the output signal.
    Type: Grant
    Filed: March 23, 2007
    Date of Patent: August 27, 2013
    Assignee: Realtek Semiconductor Corp.
    Inventor: Chao-Cheng Lee
  • Publication number: 20120119828
    Abstract: A variable gain amplifier, to amplify an audio input signal to output an audio output signal at an adjustable gain, includes an operational amplifier having an inverting input terminal, a non-inverting input terminal, and an output terminal to output the audio output signal; an attenuation-rate adjustable feedback circuit to feed back the audio output signal from the output terminal of the operational amplifier to the inverting input terminal of the operational amplifier as a feedback signal, and attenuate the audio output signal and output the feedback signal to the inverting terminal; and an attenuation-rate adjustable attenuator to attenuate the audio input signal for output it as an attenuated signal to the non-inverting input terminal of the operational amplifier. Settings of the attenuation rates of the feedback circuit and the attenuator are combined and a resolution of level of the audio output signal is increased.
    Type: Application
    Filed: November 8, 2011
    Publication date: May 17, 2012
    Applicant: RICOH COMPANY, LTD.
    Inventor: Ryuichi ARAKI
  • Publication number: 20110190028
    Abstract: Linearizers can improve the linearity of power amplifiers by canceling or reducing amplitude of non-linearity components, (e.g., IM3, IM5, IM7, IM9, etc.) generated by the power amplifier. The linearizers can obtain samples of signals output by the power amplifier and process the samples to produce a compensation signal that is applied onto or into a transmission path leading to the power amplifier's input. The compensation signal is generated such that when amplified by the power amplifier, the amplified compensation signal cancels or reduces at least a portion of the non-linearity components produced by the power amplifier. A controller can improve the correction of the non-linearity components by executing one or more calibration algorithms and/or one or more tuning algorithms and adjusting settings of the linearizer based on the results of the algorithm(s).
    Type: Application
    Filed: January 26, 2011
    Publication date: August 4, 2011
    Applicant: Intersil Americas Inc.
    Inventors: Wilhelm Steffen Hahn, Wei Chen
  • Patent number: 6697436
    Abstract: A predistortion system adaptively compensates for distortion introduced along one or more amplification chains of a power amplifier system. In one embodiment, the predistortion system includes a plurality of compensation circuits, each of which is coupled to, and configured to digitally predistort an input transmission signal to, a respective amplification chain of an antenna array system. Each such amplification chain has an output coupled to a respective antenna of the antenna array system. A processing unit monitors the input transmission signals to, and corresponding output signals from, each of the amplification chains on a time-shared basis, and generates updates to the compensation parameters used the corresponding compensation circuits.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: February 24, 2004
    Assignee: PMC-Sierra, Inc.
    Inventors: Andrew S. Wright, Bartholomeus T. W. Klijsen, Paul V. Yee, Chun Yeung Kevin Hung, Steven J. Bennett
  • Patent number: 4766396
    Abstract: A current source type current output circuit for applying to a load a current which is proportional to an input includes an amplifier of the type receiving a current and producing a voltage, and a feedback circuit for feeding back an output of the amplifier to an input terminal of the amplifier. The feedback circuit is made up of a first, a second, and a third current mirror circuit, and a first, a second, and a third resistor. An output terminal of the amplifier is connected to an input terminal of the second current mirror circuit via the third resistor and to an input terminal of the first current mirror circuit via a series connection of the first and second resistors. The load is connected to the intermediate point of the serial connection of the first and second resistors. An output terminal of the second current mirror circuit is connected to an input terminal of the third current mirror circuit.
    Type: Grant
    Filed: August 7, 1987
    Date of Patent: August 23, 1988
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Takashi Taya, Toshiyuki Tahara
  • Patent number: 3972002
    Abstract: Current and voltage feedback are used in separate frequency dependent major loops around a high gain broadband amplifier to produce frequency shaped gain and matched input and output impedances.
    Type: Grant
    Filed: December 30, 1974
    Date of Patent: July 27, 1976
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Thomas Joseph Aprille, Jr.