For Anode Patents (Class 330/202)
  • Patent number: 9871527
    Abstract: A phase-locked loop (PLL) circuit, sense amplifier circuit, and method of operating a sense amplifier circuit are disclosed. The sense amplifier circuit comprises first and second operational amplifiers, each operational amplifier respectively comprising a non-inverting input terminal, an inverting input terminal, and an output stage comprising a current gating circuit having two current gating input terminals, the output stage coupled with an output terminal, the output terminal providing a feedback signal to the inverting input terminal. The input voltage signal is received across the non-inverting input terminals of the first and second operational amplifiers, and is received across the two current gating input terminals of each of the first and second operational amplifiers, wherein the sense amplifier circuit generates a sense voltage signal across the output terminals of the first and second operational amplifiers.
    Type: Grant
    Filed: January 30, 2017
    Date of Patent: January 16, 2018
    Inventors: David M. Friend, Grant P. Kesselring, Michael A. Sperling, James D. Strom
  • Patent number: 9864420
    Abstract: A circuit, system, and method for tracking energy use in a electronic circuit. A circuit includes a DC-DC converter and a comparator. The DC-DC converter is configured to maintain a desired output voltage by switching energy to an energy storage device based on an output voltage of the energy storage device. The DC-DC converter includes an output driver configured to source current to the energy storage device. The comparator is coupled to the DC-DC converter. The comparator is configured to identify a drive state of the output driver, and to generate a signal indicative of amount of energy transferred from the DC-DC converter to a load circuit. The signal corresponds to the identified drive state.
    Type: Grant
    Filed: October 17, 2014
    Date of Patent: January 9, 2018
    Inventors: Horst Diewald, Johann Zipperer, Peter Weber, Anton Brauchle
  • Patent number: 8660277
    Abstract: A signal amplifying circuit and associated methods and apparatuses, the circuit comprising: a signal path extending from an input terminal to an output terminal, a gain controller arranged to control the gain applied along the signal path in response to a control signal; an output stage within the signal path for generating the output signal, the output stage having a gain that is substantially independent of its supply voltage, and a variable voltage power supply comprising a charge pump for providing positive and negative output voltages, the charge pump comprising a network of switches that is operable in a number of different states and a controller for operating the switches in a sequence of the states so as to generate positive and negative output voltages together spanning a voltage approximately equal to the input voltage.
    Type: Grant
    Filed: June 3, 2011
    Date of Patent: February 25, 2014
    Assignee: Wolfson Microelectronics plc
    Inventors: John P. Lesso, John L. Pennock, Peter J. Frith
  • Patent number: 8311243
    Abstract: An energy-efficient consumer device audio power output stage provides improved battery life and reduced power dissipation. A power supply having a selectable operating mode supplies the power supply rails to the power amplified output stage. The operating mode is controlled in conformity with the audio signal level, which may be determined from a volume control setting of the device and/or from a signal level detector that determines the amplitude of the signal being amplified. The power supply may be a charge pump in which the operating mode uses a capacitive divider to provide for selection of a power supply output voltage that is a rational fraction of the power supply output voltage in a full-voltage operating mode.
    Type: Grant
    Filed: December 13, 2006
    Date of Patent: November 13, 2012
    Assignee: Cirrus Logic, Inc.
    Inventors: John Christopher Tucker, Daniel John Allen, John L. Melanson, Ammisetti Prasad
  • Patent number: 7288754
    Abstract: An optical receiver. The optical receiver includes a photodiode, a differential transimpedance amplifier, a transistor, and a current source. When the photodiode receives an optical signal, a current signal transmitted from a cathode of the photodiode to an anode thereof is generated. Two input terminals of the differential transimpedance amplifier couple the current signal, and the differential transimpedance amplifier converts the current signal to a voltage signal. In addition, voltage variation of the cathode is coupled to the anode through a voltage follower composed by the transistor and the current source. As a result, voltage of the cathode and that of the anode vary in phase, effectively decreasing a value of the photodiode parasitic capacitance and improving operating bandwidth.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: October 30, 2007
    Assignee: Industrial Technology Research Institute
    Inventor: Chia-Ming Tsai
  • Patent number: 6011440
    Abstract: Amplifier circuitry is provided having an output voltage range that exceeds its supply rail voltage. Such an amplifier may be useful in battery powered applications calling for driving a high impedance load with a low current, moderate bandwidth signal The amplifier circuitry includes a transconductance amplifier, for providing a high output impedance, and a charge pump DC/DC converter, for providing a high supply voltage to the transconductance amplifier. In one embodiment of the invention, the gain of the amplifier is a function of the input voltage so as to linearize a transfer function between the amplifier input and a response of a load at the amplifier's output.
    Type: Grant
    Filed: March 18, 1997
    Date of Patent: January 4, 2000
    Assignee: Linear Technology Corporation
    Inventors: David B. Bell, Dale R. Eager
  • Patent number: 5909145
    Abstract: Sag of a power signal delivered to of an amplifier is controlled. The maximum amount of sag is limited to limit crossover distortion. A measuring circuit monitors an observed signal to generate a measured signal. A sag control circuit receives the measured signal and one or more input control signals, and in response generates a sag control signal. A regulator circuit receives the sag control signal and a raw power supply signal and in response generates a regulated DC power supply signal for the amplifier. The regulator circuit decreases the maximum power available to the amplifier as the sag control signal magnitude increases, so as to increase distortion and compression in the output signal (e.g., and achieve a "warm", "airy" or "forgiving" sound quality resembling or improving the sound of a vacuum tube amplifier).
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: June 1, 1999
    Assignee: Maven Peal Instruments, Inc.
    Inventor: David G. Zimmerman
  • Patent number: 5892404
    Abstract: A linear power amplifier having a pulse density modulated switching power supply including a power supply providing at least a relatively high DC voltage output; a voltage amplifier connected to an external signal source to amplify a relatively low voltage signal received from the external signal source into a relatively high voltage signal; a current amplifier connected to the voltage amplifier to increase the current flow associated with the relatively high voltage signal, as needed, in order to properly drive a load, wherein the current amplifier is powered by a pulse generator. The pulse generator is connected to a first line carrying the relatively high voltage signal to the load, and to a second line supplying power to the current amplifier.
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: April 6, 1999
    Assignee: VAC-com, Inc.
    Inventor: Engne Tang
  • Patent number: 5751823
    Abstract: An audio amplifier, particularly suited for automotive applications, providing improved isolation between the preamplifier section and the power amplifier section. The preamplifier section ground is isolated from the power amplifier section ground. The amplifier includes a voltage regulator with output feedback for supplying a regulated voltage to the preamplifier section. The voltage regulator is referenced to the preamplifier section ground.
    Type: Grant
    Filed: January 5, 1996
    Date of Patent: May 12, 1998
    Assignee: Rockford Corporation
    Inventors: James C. Strickland, Mark D. Albers
  • Patent number: 5635872
    Abstract: A regulated power supply control system with adjustable operating point and adjustable dynamic behavior for use with electronic power supply circuits, such as musical instrument amplifiers. The control system includes a measurement circuit (20) that generates a measured signal (22) based on an observed signal (18) in an amplifier (10); a sag control circuit (24) that generates a sag signal (32) based on the measured signal (22); a referenced circuit (34) that generates a static reference signal (38); and a regulator (44) that uses the static reference signal (38) and sag signal (32) to generate a regulated power supply output (14) that is used by the amplifier (10). The sag control circuit (24) permits adjustment of the sag signal 32 by a user-operated sag magnitude control (26), sag rate control (28), and sag recovery rate control (30).
    Type: Grant
    Filed: November 16, 1995
    Date of Patent: June 3, 1997
    Assignee: Maven Peal Instruments, Inc.
    Inventor: David G. Zimmerman
  • Patent number: 5568088
    Abstract: An amplifying apparatus for linearly amplifying a desired signal using a pair of coupled non-linear amplifiers is disclosed. The amplifying apparatus comprises a limiter for separating amplitude variations from the desired signal and producing a constant amplitude signal bearing the phase of the desired signal and an amplitude related signal. In addition, a drive signal generater produces two drive signals each dependent on the constant amplitude signal and the amplitude related signal such that each drive signal depends on the phase of the desired signal and such that the sum of the squares of the amplitudes of the drive signals is constant. Finally, a coupler couples the two drive signals to produce two constant amplitude signals for driving the pair of non-linear power amplifiers and for coupling the outputs of the power amplifiers to produce two amplified output signals, one of which is the linearly amplified desired signal and the other of which is a waste energy signal.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 22, 1996
    Assignee: Ericsson GE Mobile Communications Inc.
    Inventors: Paul W. Dent, Ross W. Lampe
  • Patent number: 5554959
    Abstract: A linear power amplifier having a pulse density modulated switching power supply comprising: power supply means for connection to a source of electrical power and adapted to provide (i) a first, relatively high DC voltage, and (ii) a second, relatively low DC voltage; voltage amplifying means for connection to a signal source and adapted to amplify a first, relatively low voltage signal received from the signal source into a second, relatively high voltage signal; current amplifying means connected to the voltage amplifying means and adapted to increase the current flow of the second, relatively high voltage signal, as needed, in order to properly drive a load, wherein the current amplifying means are normally powered by the second, relatively low DC voltage supplied by the power supply means; and pulse generating means connected to the line carrying the second, relatively high voltage signal to the load, and to the line supplying power to the current amplifying means, the pulse generating means being adapted
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: September 10, 1996
    Assignee: VAC-com, Inc.
    Inventor: Engne Tang
  • Patent number: 5396194
    Abstract: An audio frequency amplifier having a switching converter comprising source and sink rectifiers configured for sourcing and sinking current, in which the source and sink supply voltages of the rectifiers track the audio frequency signal being amplified. The amplifier has a circuit or element for discharging the output capacitors of the source and sink rectifier as necessary to prevent floating of the source and sink supply voltages. The discharging element can be a locking capacitor or one or more Zener diodes connected across the source and sink supply voltages. The discharge circuit can be one or more switching transistors connected across the freewheeling diodes of the source and sink rectifiers to actively pull the source and sink voltages down to discharge the output capacitors and thereby prevent floating. Low voltage rated parts can be used in the output stage amplifier, and in certain configurations a high voltage low current preamplifier stage can be eliminated.
    Type: Grant
    Filed: November 19, 1993
    Date of Patent: March 7, 1995
    Assignee: Carver Corporation
    Inventors: Robert C. Williamson, James J. Croft, III
  • Patent number: 5157353
    Abstract: The present invention relates to electronic circuits, such as an operational amplifiers, which have dual power supply requirements. When the power supply voltages are switched between an "off" state and an "on" state, the power supply transient voltages of the two polarities closely track each othe so as to reduce audio transients from being produced within the operational amplifiers. This tracking is accomplished by the negative polarity power supply voltage being provided for the signal amplifier at the output terminal of an unity gain operational amplifier having an inverting input terminal coupled to the positive polarity power supply voltage.
    Type: Grant
    Filed: May 3, 1991
    Date of Patent: October 20, 1992
    Assignee: Thomson Consumer Electronics, Inc.
    Inventor: Jeffery B. Lendaro
  • Patent number: 5091700
    Abstract: A method enables a musician to reduce the voltage level between a nominal level which is supplied to power an audio power amplifier including at least one vacuum tube power output device and a reduced level, by controlling AC input voltage level of an AC to DC power supply via an input transformer having a primary winding connected to receive nominal AC voltage from the AC power mains, a high voltage secondary, and a low voltage secondary for directly supplying heater power to the vacuum tube power output device.
    Type: Grant
    Filed: August 10, 1990
    Date of Patent: February 25, 1992
    Inventor: Randall C. Smith
  • Patent number: 5036292
    Abstract: A filter capacitor network includes an inductor connected in series with an aluminum electrolytic capacitor with the inductor and aluminum electrolytic capacitor bypassed with a capacitor having relatively better high frequency performance characteristics than the aluminum electrolytic capacitor. The inductor decouples the aluminum capacitor from the network at middle and upper frequencies so that the bypass capacitor dominates the characteristics of the network in that range. A signal coupling/DC blocking capacitor network of the same configuration is also disclosed. An amplifier design includes the filter network in the power supply. The filter network is also disclosed in an audio signal path for use in signal coupling/DC blocking.
    Type: Grant
    Filed: February 16, 1990
    Date of Patent: July 30, 1991
    Assignee: Audio Research Corporation
    Inventors: John R. Hjelm, Richard D. Larson
  • Patent number: 4819272
    Abstract: An intermittently driven transmitter having high power output which is driven intermittently so as to transmit a signal via, for example, a satellite in which the voltage supplied to the transmitter is boosted and supplied to a capacitor. When the signal is to be transmitted, the voltage stored on the capacitor is supplied to a constant voltage circuit which generates a constant voltage which is higher than the voltage supplied to the transmitter and which is supplied to a power amplifier in the final stage of the transmitter and, thus, the intermittent type transmitter with a suitable battery drive system is obtained.
    Type: Grant
    Filed: March 13, 1987
    Date of Patent: April 4, 1989
    Assignee: Sony Corporation
    Inventors: Norio Shimo, Norio Numata
  • Patent number: 4742311
    Abstract: A circuit in which a load connected to the output of an amplifier, and in particular for the gradient coil arrangement in a nuclear magnetic resonance tomography unit. To reduce the power loss in the amplifier, especially where, as in NMR tomography, high currents must be switched in relatively short time intervals, the supply voltage for the amplifier is delivered by a d.c. voltage generator the output voltage of which follows the input voltage in steps, but always remains a certain amount larger than the output voltage of the amplifier assigned to the respective input voltage.
    Type: Grant
    Filed: August 25, 1986
    Date of Patent: May 3, 1988
    Assignee: U.S. Philips Corporation
    Inventor: Alfred J. Van der Zwart
  • Patent number: 4719431
    Abstract: A push-pull power amplifier includes a pair of input terminals, a pair of output terminals, a pair of matched output tubes having cathode, plate, and grid terminals, and a pair of output power supplies, all of which are connected to form a bridge circuit. A floating bias supply is coupled between the grid and plate of both output tubes. A first feedback resistor couples the floating bias supply to the cathode of the first output tube. A second feedback resistor couples the floating bias supply to the cathode of the second output tube. The floating bias supply and feedback resistors provide degenerative feedback without affecting power gain.
    Type: Grant
    Filed: April 21, 1986
    Date of Patent: January 12, 1988
    Inventor: Ralph R. Karsten
  • Patent number: 4651112
    Abstract: An audio amplifier system is provided including a transformer having a first primary winding that is center-tapped, a second primary winding and a secondary winding. The amplifier system includes a battery backup system by connecting a battery to the center tap of the first primary winding. The second primary winding is connected to a source of alternating current. The output from the secondary winding is rectified and filtered to provide a positive voltage output and a negative voltage output. A complementary symmetry amplifier is provided having a positive voltage power input, a negative voltage power input, an audio signal input and an output. The positive voltage output and negative voltage output are connected, respectively, to the positive voltage power input and the negative voltage power input of the complementary symmetry amplifier.
    Type: Grant
    Filed: February 3, 1986
    Date of Patent: March 17, 1987
    Assignee: Dukane Corporation
    Inventor: Charles W. Keysor
  • Patent number: 4636741
    Abstract: Unique multi-level power amplifying circuitry is described that may be advantageously utilized in duplex portable radio transceivers which may be inserted into a vehicular adaptor for operation from the vehicle battery. Upon detecting the presence of the vehicular adaptor, the power amplifier may be operated at a second set of power levels which include levels greater than a first set of power levels for portable operation. The multi-level power amplifying circuitry of the present invention may be advantageously utilized in a variety of applications where duplex battery-operated radio transceivers may be inserted into a vehicular adaptor for operation from the vehicle battery.
    Type: Grant
    Filed: November 1, 1985
    Date of Patent: January 13, 1987
    Assignee: Motorola, Inc.
    Inventor: James E. Mitzlaff
  • Patent number: 4535303
    Abstract: In a driver circuit including at least one integrated circuit amplifier, adapted to be interconnected with a subscriber's line of a telephone system, the operating supply for the amplifier includes a pair of series connected voltage supplies having a maximum sum voltage that exceeds the breakdown voltage of the amplifier. The junction of the voltage supplies is connected to a reference, and the amplitudes of the output voltages of the two supplies are controlled in opposite directions with variations in the amplifier input signal to maintain the effective sum voltages of the supplies below the breakdown voltage of the amplifier. The series connected supplies may be employed to supply the input of a similarly connected second amplifier, with the controlled voltage supply of the second amplifier serving to supply the input of the first amplifier. In this latter arrangement, the amplitudes of the supplies of the two amplifiers are commonly controlled.
    Type: Grant
    Filed: July 22, 1982
    Date of Patent: August 13, 1985
    Assignee: U.S. Philips Corporation
    Inventors: Franciscus A. C. M. Schoofs, Aloysius J. Nijman
  • Patent number: 4449103
    Abstract: A method for amplifying electric signals, an amplifier circuit and application of this amplifier circuit as the modulator stage of a subsequent amplifier, employing a variable anode voltage for the purpose of improving the efficiency of amplifiers and particularly of high-power modulation amplifiers which are used, for example, in broadcast transmitters for the amplitude modulation of the radio-frequency output stage. From the modulation signal to be amplified, a control signal is derived in a control stage, this control signal being associated with the amplitude of the envelope of this modulation signal and being used for controlling the output voltage of a modulator/rectifier. The control signal is caused to follow the modulation signal within a presettable response time.
    Type: Grant
    Filed: December 4, 1981
    Date of Patent: May 15, 1984
    Assignee: BBC Brown, Boveri & Company, Limited
    Inventor: Bohumil Kyrian
  • Patent number: 4442407
    Abstract: The power supply potential applied to the final stage of an RF amplifier is odulated by means of an adaptive power supply. The power supply potential applied to the final RF amplifier is controlled by a first control loop in accordance with an error signal derived from a comparison of a signal corresponding to the weighted sum of the magnitude of the supply voltage applied and the current drawn by the final amplifier and the amplitude of the modulating signal. Additionally, an automatic level control circuit controls the level of the RF output signal in a second control loop in accordance with a comparison between the magnitude of the RF output of the amplifier and the amplitude of the modulating signal.
    Type: Grant
    Filed: June 11, 1982
    Date of Patent: April 10, 1984
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Thomas R. Apel
  • Patent number: 4320350
    Abstract: A sliding power supply for a radio frequency power amplifier provides power to the power amplifier that is indirectly controlled by the load impedance voltage standing wave ratio of the amplifier. The overall results being an enhancement or improvement in the efficiency of the RF power amplifier into a varying RF load mismatch.
    Type: Grant
    Filed: November 29, 1979
    Date of Patent: March 16, 1982
    Assignee: Rockwell International Corporation
    Inventor: Michael J. Drapac
  • Patent number: 4213099
    Abstract: Calibration means, including an optiosolator, for a hydrophone preamplifier hich couples to a remote DC supply source and a remote load through a long, two-wire cable. The output signal of the optoisolator is fed to the amplifier in series with the hydrophone output signal, the input to the optoisolator being an AC calibration signal. In an array of preamplifiers, the same calibration signal is fed to all the preamplifiers by connecting the optoisolators in series with each other and the source of the AC calibration signal.
    Type: Grant
    Filed: November 20, 1978
    Date of Patent: July 15, 1980
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Craig K. Brown
  • Patent number: 4152661
    Abstract: A modulation amplifier having an output amplifier element which contains an accumulation choke, a switching tube and a low-pass filter connected in series, with a commutation diode connected to the switching tube is disclosed. The switching tube is controlled by pulse duration-modulated pulses and a semiconductor switch is connected between the switching tube and the pulse duration-modulated pulses. The semiconductor switch comprises two branches, each of which are connected to a different electric potential and each including a controlled semiconductor which acts as a switch, one of the branches being controlled into a conducting state and the other of the branches being controlled into a non-conducting state upon a potential jump in the pulse time-modulated pulses in either the increasing or decreasing directions.
    Type: Grant
    Filed: April 4, 1978
    Date of Patent: May 1, 1979
    Assignee: Licentia Patent-Verwaltungs-G.m.b.H.
    Inventor: Jurgen Zeis
  • Patent number: 4117418
    Abstract: An electric amplifier useful for instance in simulators for strong electric signals, comprising several partial amplifiers so connected and voltage fed that they will amplify an interval each of the input voltage. Every partial amplifier comprises at least one amplification component and two gates, of which gates one is blocking those potentials applied to the component that are less than a given first value but is open for potentials exceeding said value while the other gate is open for potentials less than a given second value greater than said first value but is blocking the component for potentials exceeding said second value.
    Type: Grant
    Filed: January 14, 1977
    Date of Patent: September 26, 1978
    Inventor: Lennart Harry Erik Hoglund
  • Patent number: 4115739
    Abstract: In order to eliminate distortion a power amplifier is biased to Class-A or Class-B operation and in order to minimize the power loss the supply voltage of a power source is decreased as much as possible and the power source is driven by another highly efficient power amplifier so as to follow an output voltage.
    Type: Grant
    Filed: April 18, 1977
    Date of Patent: September 19, 1978
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nobuya Sano, Hiroshi Goto, Yutaka Hirota