Power Supply From Deflection Circuit Source Patents (Class 315/411)
  • Patent number: 4916366
    Abstract: A horizontal deflection circuit includes a flyback transformer. A secondary winding of the flyback transformer is coupled in series with a diode switch to produce a trace rectified supply voltage that energizes a vertical deflection amplifier. The diode switch also provides switching operation in an East-West diode modulator. During, for example, service mode operation, when the vertical raster is collapsed, the trace current in the secondary winding is substantially reduced. The reduced trace current is sensed for producing a control signal that causes the peak current supplied by the diode switch to the diode modulator to be smaller than the trace current in the secondary winding. This ensures that the diode switch remains conductive throughout horizontal trace, thereby, preventing an undesirable increase in the supply voltage from occuring.
    Type: Grant
    Filed: November 21, 1988
    Date of Patent: April 10, 1990
    Assignee: Thomson Consumer Electronics, Inc.
    Inventors: James A. Wilber, Joseph C. Stephens
  • Patent number: 4910531
    Abstract: An image photographing apparatus photographs an image displayed by a display unit such as a CRT monitor on a photosensitive medium such as a photographic film. The displayed image is formed on the photosensitive medium by an image-forming optical mechanism which includes the display unit for displaying the image with an electron beam. A transformer for producing a desired voltage for energizing the image photographing apparatus is substantially spaced from the display unit and oriented such that leakage fluxes from the transformer will be directed substantially parallel to the electron beam in the display unit, for allowing the image to be displayed by the display unit with high accuracy without being adversely affected by the leakage fluxes.
    Type: Grant
    Filed: August 22, 1988
    Date of Patent: March 20, 1990
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Akira Mitake
  • Patent number: 4905116
    Abstract: An X-radiation protection circuit in a television receiver is responsive to both high voltage and high beam current conditions. A first detector is interconnected with an electron beam power source and monitors the beam current therefrom. The first detector produces a first voltage proportional in magnitude to the electron beam current. A second detector monitors a high voltage transformer that produces a potential for operating on the electron beam and the second detector produces a second voltage that is proportional in magnitude to the high voltage potential. A monitoring circuit constantly monitors both the first and second voltages and produces a trigger signal whenever the additive sum of the first and second voltages exceeds a selected magnitude. In this manner, a trigger signal indicates an excessively high combination of electron beam current and high voltage.
    Type: Grant
    Filed: December 1, 1988
    Date of Patent: February 27, 1990
    Assignee: North American Philips Corp.
    Inventor: Willy F. Stierberger
  • Patent number: 4901156
    Abstract: An automatic brightness limiting (ABL) circuit is provided for preventing the color dispersion of a displayed picture which is caused by an excessive beam current flowing through a color picture tube. The variation of the beam current is detected at the lower terminal of the serial resistor circuit of the high voltage output stage of a flyback transformer that is included in the high voltage output section. The detected beam current variation is amplified and, in turn, supplied to a color output section as a control voltage through a brightness adjusting section.
    Type: Grant
    Filed: December 23, 1987
    Date of Patent: February 13, 1990
    Assignee: Goldstart Co., Ltd.
    Inventor: Keun J. Yook
  • Patent number: 4900988
    Abstract: A high voltage stabilizing circuit in a monitor, which has various horizontal synchronized frequencies input thereto. The high voltage stabilizing circuit allows the heating of the voltage control transistor to be reduced.
    Type: Grant
    Filed: December 31, 1987
    Date of Patent: February 13, 1990
    Assignee: Goldstar Co., Ltd.
    Inventor: Geun J. Yuk
  • Patent number: 4891564
    Abstract: A dynamic beam current focussing circuit for providing improved focussing across the screen of a cathode ray video display tube utilizes a tuned voltage step-up transformer to achieve sufficient amplitude of horizontal sweep waveform components of the dynamic focussing voltage. The circuit is useful for high definition television and video display units.
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: January 2, 1990
    Assignee: U.S. Philips Corporation
    Inventor: Gregory T. B. Crowley
  • Patent number: 4890044
    Abstract: A signal suppression component such as a ferrite shield bead includes a cylindrical magnetically permeable element that has a passage formed through it. The passage is filled with an elastic silicone rubber compound. When the component is placed on a conductor or component lead, the elastic material forms a dampening layer between the conductor and the permeable element to prevent audible vibration of the element due to current flow in the conductor.
    Type: Grant
    Filed: March 28, 1988
    Date of Patent: December 26, 1989
    Assignee: RCA Licensing Corporation
    Inventor: Randall C. Clayburn
  • Patent number: 4885509
    Abstract: A high voltage generating apparatus for supplying a high voltage to a cathode-ray tube is provided with a flyback transformer which has a low voltage coil and a high voltage coil.A first circuit detects a quantity of current which flows in the low voltage coil, and a second circuit detects a quantity of current which flows in the high voltage coil. A thyristor turns on when the quantity of current of the first circuit becomes larger than that of the second circuit to fusing-disconnect a fuse connected to a power supplying circuit, thus stopping the operation of the flyback transformer.
    Type: Grant
    Filed: April 29, 1988
    Date of Patent: December 5, 1989
    Assignee: Murata Manufacturing Company
    Inventor: Hiroshi Ikeuchi
  • Patent number: 4885673
    Abstract: A switching power supply comprises a primary regulation system (CI3) and a secondary regulation system (CI2, CI1), supplying control signals (Pp, Ps) for a main switch (TP) and further comprises a comparison means (22), the output of which (Is) is set to "1" when the transformer (TA) of the switching current is demagnetized. A logic circuit (CL) receives the output signals (Is, Pp, Ps) and supplies on its output (25) a control signal (VS5) for the main switch (Tp) which can be set to "0" for the switching OFF of the main switch or to "1" for its switching ON, as a function of the following criteria: the control signal is set to "1" if the comparator output signal is set to "1", and if the output signal of at least one of the regulators is set to "1", and the control signal is set to "0" when the regulator output signal which has caused to control signal to be set to "1" is set to "0".
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: December 5, 1989
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventor: Maige Philippe
  • Patent number: 4885510
    Abstract: A compensation circuit for maintainng a CRT vertical raster size substantially constant with beam current changes includes a sensing resistor connected in series with the high voltage winding. The sensing resistor develops an input bias for a compensation transistor that has its output circuit connected across the vertical size control. Increases in beam current are reflected in increases in current in the high voltage winding which cause the compensation transistor to conduct more heavily and supply more current to the vertical size control. The size control is part of the discharge circuit of the vertical timing capacitor and the increased current from the transistor reduces the discharge time of the timing capacitor. Consequently the peak to peak voltage of the vertical current ramp is decreased.
    Type: Grant
    Filed: August 8, 1988
    Date of Patent: December 5, 1989
    Assignee: Zenith Electronics Corporation
    Inventor: Lloyd E. Matthews
  • Patent number: 4870331
    Abstract: Circuit arrangement for a picture display device for the stabilization of the size of the picture displayed.In picture display devices having cathode-ray tubes, the first anode voltage for these tubes is recovered from the retrace pulse at a corresponding winding of the line transformer, this anode voltage source being of a relatively high ohmic value. As a result thereof, the anode voltage decreases versus an increasing anode current, and consequently, the picture displayed on the display screen becomes larger. More specifically, for picture display devices for word processing, which have a positive display, a very different anode current can flow because of different brightness settings. So as to produce nevertheless a largely constant anode voltage, a circuit arrangement which behaves as a negative resistance is provided at the lower end of the high-voltage winding.
    Type: Grant
    Filed: October 25, 1988
    Date of Patent: September 26, 1989
    Assignee: U.S. Philips Corporation
    Inventor: Paul H. Heinzerling
  • Patent number: 4868662
    Abstract: An external-power stage suitable for use with television sets, for example. A transformer is provided with control circuits in both the primary side and the secondary side. Each of the control circuits have pulse-width modulators which provide pulses to an electronic switch. The control circuit on the primary side provides pulses to that switch of varying pulse width and of sufficient magnitude to maintain the television set in a standby mode. The control circuit in the secondary side of the transformer, on the other hand, comes into operation when the television set is turned on and provides pulses to the electronic switch while operating with the control circuit in the primary side for a predetermined period of time. Thereafter, the control circuit in the secondary side takes over the function of providing pulses to the electronic switch while the control circuit on the primary side is switched to an inoperative stage.
    Type: Grant
    Filed: September 15, 1988
    Date of Patent: September 19, 1989
    Assignee: Deutsche Thomson-Brandt GmbH
    Inventors: Uwe Hartman, Michel van den Driesche, Udo Mai, Philippe Maige
  • Patent number: 4868464
    Abstract: In a horizontal deflection output circuit adapted for correction of horizontal linearity in a television receiver or the like, and which comprises a switching transistor, a damper diode, a horizontal deflecting coil and an S correcting capacitor connected in series to the horizontal deflecting coil; the terminal voltage of the S correcting capacitor is modulated by a sawtooth signal produced by a linear distortion correcting circuit synchronously with a horizontal periodic signal. The sawtooth signal produced by the switching transistor and fed to the horizontal deflecting coil is applied to the S correcting capacitor which feeds an S correcting current to the horizontal deflecting coil, so as to correct the image distortion caused particularly by the resistance component of the horizontal deflecting coil.
    Type: Grant
    Filed: July 6, 1988
    Date of Patent: September 19, 1989
    Assignee: Sony Corporation
    Inventors: Junzo Watanabe, Seiji Kawaberi
  • Patent number: 4868466
    Abstract: During a power-up mode of a television receiver power supply, a first run supply voltage is generated by rectifying a retrace voltage in a flyback transformer of a horizontal output stage of the television receiver. The rectified voltage is coupled through a resistor and a diode to a power supply voltage receiving terminal of a load circuit. A voltage regulator that includes a pass transistor regulates the voltage at the terminal during both the power-up and standby modes. During the power-up mode, when the ambient temperature is higher than during the standby mode, the current in the transistor is lowered, as a result of a current that is coupled to the terminal via the diode. This reduces the power dissipation in the transistor during the power-up mode. A second transistor, having a base electrode that is coupled to the anode of the diode, generates a second run supply voltage that is temperature compensated at an emitter electrode of the transistor.
    Type: Grant
    Filed: March 29, 1988
    Date of Patent: September 19, 1989
    Assignee: RCA Licensing Corporation
    Inventor: Jeffery B. Lendaro
  • Patent number: 4866525
    Abstract: An SCR switch of a switch mode power supply is coupled between an unregulated supply voltage and a filter capacitor. A regulator oscillator generates trigger pulses for controlling a switching operation of the SCR switch of the power supply to produce an output supply voltage that energizes a deflection circuit. The regulator oscillator produces trigger pulses that are applied to the SCR switch during both power-up and power-off operation. A resistor coupled between the unregulated supply voltage and the filter capacitor maintains the filter capacitor charged during power-off operation to prevent the trigger pulses from causing the latching operation in the SCR switch throughout the power-off operation. In this way, an audible parasitic vibration sound is not being generated by the power supply during the power-off operation.
    Type: Grant
    Filed: November 1, 1988
    Date of Patent: September 12, 1989
    Assignee: Thomson Consumer Electronics, Inc.
    Inventors: Enrique Rodriguez-Cavazos, Steven C. Wetta, Lawrence E. Smith, Sammy S. Henig
  • Patent number: 4866353
    Abstract: A diode is coupled to a low voltage end terminal of a tertiary high voltage winding of a horizontal flyback transformer. The diode is back biased during trace and during a portion of the second half of retrace by a voltage that is coupled to the diode through a resistor from a B+ voltage source. When the diode is back biased, the resistor dampens parasitic ringing current in the tertiary winding caused by the leakage inductance of the transformer. During a portion of retrace, occuring prior to the time the diode is back biased, the diode is conductive and bypasses the resistor. This prevents the resistor from increasing the output impedance at the ultor terminal.
    Type: Grant
    Filed: August 31, 1988
    Date of Patent: September 12, 1989
    Assignee: RCA Licensing Corporation
    Inventor: Peter E. Haferl
  • Patent number: 4864481
    Abstract: A switching-type power supply for a video apparatus includes regulating circuits that respond to both voltage and current information in order to generate pulse width modulated signals for the power supply switching device. The regulating circuits are electrically nonisolated from the output load circuits to provide direct feedback from one of the load circuit voltage supplies in order to effect accurate regulation of the supply voltage. Primary current flow information is provided via an electrically isolated winding such that all regulation circuitry is electrically nonisolated from the load circuit supplies.
    Type: Grant
    Filed: October 31, 1986
    Date of Patent: September 5, 1989
    Assignee: RCA Licensing Corporation
    Inventor: Peter D. Osman
  • Patent number: 4864406
    Abstract: An arrangement in a television receiver in which a sychronized external power stage supplies operating voltage to a remote-control receiver and a microprocessor connected thereto. A horizontal drive circuit is controlled by the microprocessor, and a horizontal end stage is connected to the horizontal drive circuit. The external power stage supplies power during stand-by operation only to the remote-control receiver and microprocessor along with the voltage for operating the horizontal drive circuit and the end stage. Thyristors are connected to the external power stage for supplying power to all other circuit stages in the television receiver. The thyristors have gate electrodes activated by the horizontal end stage for cutting off the thyristors during the stand-by operation and interrupting the supply of power to all other circuit stages in the television receiver, for minimizing the power consumption of the television receiver.
    Type: Grant
    Filed: September 15, 1988
    Date of Patent: September 5, 1989
    Assignee: Deutsche Thomson-Brandt GmbH
    Inventors: Uwe Hartmann, Udo Mai
  • Patent number: 4845410
    Abstract: A conventional flyback type deflection system develops a high DC voltage that is sensed by a small potentiometer connected in series with a bleeder resistor coupled across the flyback winding. A differential amplifier compares the sensed voltage with a reference voltage and drives a voltage controlled oscillator, which develops a pulse output whose frequency is a function of the sensed voltage. The VCO drives a FET that in turn controls current flow through a small flyback coil arrangement. The output of the coil arrangement is rectified and a DC compensating voltage is developed across a capacitor that is coupled in series with the high voltage flyback winding.
    Type: Grant
    Filed: June 30, 1988
    Date of Patent: July 4, 1989
    Assignee: Zenith Electronics Corporation
    Inventor: Leroy A. Sutton
  • Patent number: 4843285
    Abstract: A regulator coupled to the main supply voltage generates a B+ scan voltage for a horizontal flyback transformer of a horizontal deflection circuit. A supply voltage is developed from a trace voltage in a flyback transformer secondary winding. The supply voltage is indicatiave of the horizontal deflection current amplitude. A decrease in mains supply voltage that cannot be compensated by the regulator, causes a corresponding decrease in the B+ scan and supply voltage and in a horizontal deflection current amplitude. The supply voltage is applied to the series arrangement of first and second resistors and a zener diode. A control voltage developed from the supply voltage, at a junction of the first and second resistors, is applied to a control terminal of a vertical deflection circuit for controlling the amplitude of the vertical deflection current. A decrease in the control voltage produces a greater proportional decrease in the vertical deflection current.
    Type: Grant
    Filed: July 5, 1988
    Date of Patent: June 27, 1989
    Assignee: Thomson Consumer Electronics, Inc.
    Inventors: Lin T. Chin, James A. Wilber
  • Patent number: 4841201
    Abstract: A stacked or laminated-layer type of flyback transformer includes a plurality of high voltage windings wound in regular order in a direction of the winding axis and arranged on the same core cylinder. The high voltage windings in the respective layers are connected in series with each other by diodes and so that a voltage is generated with a direction of stacking of these windings. A winding start position of the first layer high voltage winding nearest a primary winding is lagged with respect to the winding start positions of the second layer winding and subsequent layer winding. The winding start position of the first layer winding is selected to be the position of, for example, 0 to 25% when the winding width on the core cylinder is 100%.
    Type: Grant
    Filed: November 4, 1987
    Date of Patent: June 20, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Kazuyoshi Takizawa, Kiyoshi Watanuki
  • Patent number: 4841406
    Abstract: An X-radiation protection circuit in a television receiver is responsive to both high voltage and high beam current conditions. A first detector is interconnected with an electron beam power source and monitors the beam current therefrom. The first detector produces a first voltage proportional in magnitude to the electron beam current. A second detector monitors a high voltage transformer that produces a potential for operating on the electron beam and the second detector produces a second voltage that is proportional in magnitude to the high voltage potential. A monitoring circuit constantly monitors both the first and second voltages and produces a trigger signal whenever the additive sum of the first and second voltages exceeds a selected magnitude. In this manner, a trigger signal indicates an excessively high combination of electron beam current and high voltage. This circuit is constantly responsive to both high voltage and electron beam current.
    Type: Grant
    Filed: September 28, 1987
    Date of Patent: June 20, 1989
    Assignee: North American Philips Consumer Electronics Corp.
    Inventor: Willy F. Stierberger
  • Patent number: 4835668
    Abstract: A power supply circuit for generating two direct voltages. A preload, having a tap for deriving the second voltage, is arranged between the lead conveying the first voltage and a reference potential. To prevent mutual influences between the two voltages, the preload is in the form of a series arrangement of at least one resistor and a plurality of reverse-biassed semiconductor diodes, an abrupt change of the differential resistance occurring above a given value of the current through these diodes. A controllable semiconductor element for controlling the second voltage is incorporated between the tap and the lead conveying the second voltage. The first voltage may be an E.H.T. for a final anode of a picture display tube, the second voltage is then a focussing voltage for a focussing electrode of this tube.
    Type: Grant
    Filed: February 29, 1988
    Date of Patent: May 30, 1989
    Assignee: U. S. Philips Corporation
    Inventors: Erich J. Palm, Johannes B. Meertens
  • Patent number: 4831311
    Abstract: A high voltage stabilization curcuit for a multi-frequency horizontal deflection circuit in a video monitor or receiver and having a plurality of supply voltages applied to the flyback transformer of the deflection circuit through the operation of a pair of series connected switching circuits whereby different amplitude power supply voltages are coupled to the primary winding of the flyback transformer depending upon the horizontal drive frequency being utilized. The high voltage output across the secondary winding of the flyback transformer is stabilized through a feedback circuit which senses the output across the secondary winding of the flyback transformer to increase the amplitude of the horizontal drive applied to the primary winding when the high voltage output across the secondary winding decreases by means of a boost circuit coupled to the horizontal output circuit coupled to the primary winding.
    Type: Grant
    Filed: December 31, 1987
    Date of Patent: May 16, 1989
    Assignee: Goldstar Co., Ltd.
    Inventor: Geun J. Yug
  • Patent number: 4829216
    Abstract: In a switching power supply for a television apparatus, a switching stage is coupled to a source of DC input voltage and to an energy storage inductance for developing a source of DC supply voltage. Operation of the switching stage generates a switched waveform voltage in the inductance. The primary winding of a flyback transformer is coupled to and energized by the DC supply voltage. A second winding of the flyback transformer is coupled to the inductance and provides a magnetic path, via the flyback transformer, for energy to circulate between the source of DC supply voltage and the energy storage inductance. An auxiliary winding is magnetically coupled to the inductance and to a load circuit, such as a high power audio stage, for transferring at least a portion of the circulating energy to the load circuit. Additionally, the flyback transformer may be used to directly transfer energy to the load circuit.
    Type: Grant
    Filed: May 16, 1988
    Date of Patent: May 9, 1989
    Assignee: RCA Licensing Corporation
    Inventor: Enrique Rodriguez-Cavazos
  • Patent number: 4829414
    Abstract: A circuit for generating a constant DC high voltage responsive to an input signal having various frequencies, having a frequency-voltage converter responsive to the input signal to generate a voltage signal corresponding to the frequency of the input signal. The voltage signal is applied to an oscillation circuit and a voltage control circuit, respectively, as a control signal. The output from the oscillation circuit is coupled to one terminal of a primary coil of a flyback transformer (FBT), and the output from the voltage control circuit is coupled to the other terminal of the primary coil of the flyback transformer (FBT).
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: May 9, 1989
    Assignee: Goldstar Co., Ltd.
    Inventor: Keun J. Yook
  • Patent number: 4825129
    Abstract: A video display apparatus includes a cathode ray tube and a high voltage transformer. The high voltage transformer incorporates a high voltage winding having a tap which provides a focus voltage for the electron gun assembly of the cathode ray tube. The transformer also includes a supply winding which provides power to the electron gun assembly drive circuit. The supply winding is wound to be closely coupled to the portion of the high voltage winding not associated with the generation of focus voltage so that increasing beam current produces nonuniform loading of the high voltage winding.
    Type: Grant
    Filed: October 29, 1987
    Date of Patent: April 25, 1989
    Assignee: RCA Licensing Corporation
    Inventor: Leroy W. Nero
  • Patent number: 4823052
    Abstract: A horizontal deflection high-voltage circuit using the diode modulation horizontal deflection circuit is provided with a means detecting the high voltage output from the flyback transformer for supplying the input terminal of the flyback transformer with a control signal which controls the high voltage to be kept constant and a means detecting a variation in the control signal for supplying one end of a modulation coil with a control signal which controls the horizontal deflection current to be kept constant, whereby a horizontal deflection high-voltage circuit practically free from irregularity of adjustment and deterioration due to aging is provided.
    Type: Grant
    Filed: June 9, 1988
    Date of Patent: April 18, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Makoto Onozawa, Koji Kito, Michitaka Osawa
  • Patent number: 4823248
    Abstract: High voltage generators are generally arranged to step up flyback pulses from a horizontal deflection circuit by means of a flyback transformer consisting of a primary low voltage coil and a secondary high voltage coil, rectifying the high voltage output through a rectification circuit for application to the anode of a cathode-ray tube. However, such a flyback transformer construction has an inherent drawback that the voltage of the high voltage output is varied by variations in the high voltage output current due to leakage inductance, resulting in load fluctuations.
    Type: Grant
    Filed: April 5, 1988
    Date of Patent: April 18, 1989
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Hiroshi Ikeuchi, Nobuaki Imamura
  • Patent number: 4820959
    Abstract: A projection cathode ray tube burn protection circuit includes a buffer transistor supplied with a 60 Hz square wave signal from an optical coupler. A PNP and NPN combination of transistors full wave rectifiers the buffer output. The rectified signal is divided down to reduce the magnitude of the alternating current components therein and applied to the base of a switch transistor that is normally maintained in saturation for swamping out the alternating current components. The switch transistor drives a high voltage shut down transistor and a blank transistor for shutting down the high voltage generating system and for blanking the cathode ray tube, respectively, in the event the power input to the optical coupler is disrupted.
    Type: Grant
    Filed: July 22, 1988
    Date of Patent: April 11, 1989
    Assignee: Zenith Electronics Corporation
    Inventor: Donald E. Griffey
  • Patent number: 4814672
    Abstract: Circuitry for limiting a rectified operating voltage.To recover energy from unutilized power from the secondary winding of a switching-network transformer, it is recirculated to the primary winding through a diode. When appliances fail, the excess energy component can increase to the extent that components are destroyed because the operating voltage increases.To prevent this situation the excess energy is recirculated into a higher operating voltage U.sub.S through a diode and through another secondary winding of the transformer. The number of turns in the second secondary winding and its polarity ensure that the flyback voltage U.sub.R will be higher than the difference between U.sub.S and U.sub.B.Switching-network components in conjunction with rectifier modulators in television receivers.
    Type: Grant
    Filed: March 4, 1988
    Date of Patent: March 21, 1989
    Assignee: Deutsche Thomson-Brandt GmbH
    Inventors: Franz Dieterle, Uwe Hartmann, Udo Mai
  • Patent number: 4812720
    Abstract: A deflection circuit output stage generates in a deflection flyback resonant circuit a first flyback voltage at a horizontal frequency. A switch generates in a second flyback resonant circuit a second flyback voltage at the horizontal frequency having a phase relative to that of the first flyback voltage that is controllable. The first and second flyback voltages are summed and applied to a voltage tripler that produces an ultor voltage. A control circuit varies the phase of the second flyback voltage in a negative feedback manner that stabilizes the ultor voltage over a wide range of beam current variations.
    Type: Grant
    Filed: June 6, 1988
    Date of Patent: March 14, 1989
    Assignee: RCA Licensing Corporation
    Inventor: Peter E. Haferl
  • Patent number: 4812719
    Abstract: A switch regulator includes a controllable SCR switch that is coupled in series with a filter inductor and a horizontal deflection generator, and the series combination is coupled across a source of unregulated direct voltage for providing a path for an increasing current flow in the inductor during a portion of a trace interval in which the switch is closed. Horizontal rate signals are coupled from the deflection generator to the switch via a first winding for controlling the opening of the switch. A catch diode is coupled to the filter inductor to form a path for a decreasing current flow in the first inductor during at least a portion of a retrace interval. The first winding is coupled in series with a second inductor to form an arrangement that is coupled between the unregulated voltage and the SCR switch. A current in the second inductor maintains the switch conductive during a portion of retrace that varies in accordance with a beam current for improving regulation of an ultor voltage.
    Type: Grant
    Filed: April 20, 1988
    Date of Patent: March 14, 1989
    Assignee: Thomson Consumer Electronics, Inc.
    Inventors: Joseph C. Stephens, Lawrence E. Smith, Michael E. Boyer
  • Patent number: 4808891
    Abstract: In a high voltage generator comprising a flyback transformer having a primary winding and a secondary winding, a horizontal deflection circuit connected to the primary winding of the flyback transformer, and a rectifier diode connected to the secondary winding of the flyback transformer, a resonance circuit including a saturable transformer and a capacitor is inserted between the primary winding of the flyback transformer and a power source, and a signal corresponding to the value of a high voltage load current is applied to a control winding of the saturable transformer. When the value of the high voltage load current is very small, the resonance circuit resonates with a higher harmonic of a flyback pulse to remove this higher harmonic component. As the value of the high voltage load current increases, the inductance value of the secondary winding of the saturable transformer changes to change the resonance frequency of the resonance circuit.
    Type: Grant
    Filed: June 22, 1988
    Date of Patent: February 28, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Kiyoshi Watanuki, Kazuyoshi Takizawa
  • Patent number: 4801852
    Abstract: A horizontal deflection circuit for performing horizontal sweep operation of a CRT includes a saturable reactor having controlled windings connected through the primary winding of a flyback transformer to the CRT horizontal deflection coil, to supply deflection current thereto from a voltage supply produced from a voltage control circuit. The level of this supply voltage is controlled by feedback operation in accordance with the amplitude of pulses produced from an output winding of the flyback transformer such as to maintain this pulse amplitude at a fixed value, and hence maintain an EHT voltage derived from pulses from a secondary winding of the transformer at a fixed value. These fixed values are held constant when a DC current passed through the reactor control winding is varied to adjust the inductance of the controlled windings, and thereby adjust the horizontal sweep width produced on the CRT screen.
    Type: Grant
    Filed: October 22, 1986
    Date of Patent: January 31, 1989
    Assignee: Victor Company of Japan, Ltd.
    Inventor: Shigeru Kashiwagi
  • Patent number: 4788591
    Abstract: Television receiver including a switched-mode power supply which is regulated and capable of functioning both in self-oscillating mode and under the control of a line frequency synchronization. During normal operation there is synchronization, and the line time base supplies most of the supply voltages to the circuits of the receiver. To change to the stand-by state the drive of the line transistor is stopped, which stops most of the circuits depending thereon. The switched-mode power supply continues to function but then in the self-oscillating mode, and supplies the stand-by device via a secondary winding of its storage inductor.
    Type: Grant
    Filed: December 1, 1987
    Date of Patent: November 29, 1988
    Assignee: U. S. Philips Corporation
    Inventor: Alain Decraemer
  • Patent number: 4788618
    Abstract: A high voltage protecting circuit in a cathode ray tube apparatus which comprises a main power switch adapted to be connected in series with an electric power source, a flyback transformer having primary, secondary and third windings, a rectifying circuit connected with the main power switch for rectifying a power source voltage originating from the power source and to be supplied to the flyback transformer, a switching device connected between the main power switch and rectifying circuit and provided with a control terminal, and a high voltage detecting and controlling device for comparing an output voltage, produced across the third winding of the flyback transformer, with a reference voltage and for generating a control signal when the output voltage exceeds the reference voltage. The control signal is utilized to hold the switching device in an OFF position.
    Type: Grant
    Filed: July 9, 1987
    Date of Patent: November 29, 1988
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kenji Kimura
  • Patent number: 4780648
    Abstract: In a deflection apparatus which corrects for inside pincushion distortion, a deflection winding and a retrace capacitance form a retrace circuit during a retrace interval. A trace capacitance forms a trace resonant circuit with the deflection winding during the trace interval. A circuit branch that includes a second capacitance and a modulation inductance is coupled to the trace capacitance during the trace interval to form with the trace capacitance a second resonant circuit having a resonance frequency that is substantially higher during the trace interval than that of the trace resonant circuit. A current in the circuit branch modulates the trace parabolic voltage across the trace capacitance in a manner to reduce inside pincushion distortion. A supply current is coupled to an intermediate terminal of the modulation inductance for reducing "mouseteeth" raster distortions.
    Type: Grant
    Filed: September 29, 1987
    Date of Patent: October 25, 1988
    Assignee: RCA Licensing Corporation
    Inventor: Peter E. Haferl
  • Patent number: 4774584
    Abstract: The primary winding of a high-voltage transformer is periodically connected to an operating voltage source at the television line scanning frequency. The secondary winding is subdivided into several component windings which are connected to each other through diodes. A further diode provides the output for the high voltage. A somewhat similar circuit with interposed diodes can provide a center tap and full-wave rectification. A control voltage derived by voltage division from the high voltage is supplied to regulating means for holding the high voltage constant by controlling the width of the driving pulses for the semiconductor switch or by directly controlling the operating voltage connected to the transformer through the semiconductor switch.
    Type: Grant
    Filed: December 22, 1986
    Date of Patent: September 27, 1988
    Assignee: Blaupunkt-Werke GmbH
    Inventor: Karl-Hans Schmadel
  • Patent number: 4771220
    Abstract: In a television receiver with a drive transformer for the horizontal output stage, the heater voltage for the picture tube is inductively obtained from the drive transformer.
    Type: Grant
    Filed: January 30, 1986
    Date of Patent: September 13, 1988
    Assignee: Standard Elektrik Lorenz A.G.
    Inventor: Klaus Reh
  • Patent number: 4761723
    Abstract: A first run supply voltage is generated, during a power-up mode of a television receiver power supply, by rectifying a retrace voltage in a flyback transformer of a horizontal output stage of the television receiver. The rectified voltage is coupled through a resistor and a diode to a power supply voltage receiving terminal of an integrated circuit that generates a horizontal rate drive signal. The drive signal provides switching timings to the output stage. A standby supply voltage is coupled, during a standby mode, to the terminal. A shunt regulator regulates the voltage at the terminal during both the power-up and standby modes. A transistor having a collector electrode that is coupled to the run supply voltage and a base electrode, that is coupled to the anode of the diode, generates a second run supply voltage that is temperature compensated at an emitter electrode of the transistor.
    Type: Grant
    Filed: February 27, 1987
    Date of Patent: August 2, 1988
    Assignee: RCA Licensing Corporation
    Inventor: Jeffery B. Lendaro
  • Patent number: 4754206
    Abstract: A shutdown circuit for a CRT deflection and high voltage system includes a magnetic core having a one turn sensing coil in series with the emitter-collector of the horizontal output transistor that supplies the CRT deflection means and high voltage generator. A one turn pickup coil is also coupled to the magnetic core and develops a signal responsive to the load current in said transistor. The signal is rectified and supplied to the base-emitter junction of a switch transistor having its emitter-collector path connected between the junction of the power supply fuse and a B+ voltage terminal and ground. In the event of a fault in the load supplied by the horizontal output transistor, the switch transistor is driven conductive to place a short circuit across the B+ voltage terminal to rapidly blow the fuse.
    Type: Grant
    Filed: August 26, 1986
    Date of Patent: June 28, 1988
    Assignee: Zenith Electronics Corporation
    Inventor: Tom L. Sorensen
  • Patent number: 4740877
    Abstract: A power supply for a video display apparatus includes circuitry that produces a pulse width modulated signal in response to the selected horizontal deflection rate. The pulse width modulated signal controls the switching of an FET through a transformer to provide a load circuit operating voltage representative of the deflection frequency. A turn-off signal for the FET is provided to a turn-off transistor from the primary winding of the transformer to insure rapid turn off of the FET.
    Type: Grant
    Filed: June 27, 1986
    Date of Patent: April 26, 1988
    Assignee: RCA Corporation
    Inventor: James H. Wharton
  • Patent number: 4737851
    Abstract: A control circuit of a television receiver power supply is constructed using a plurality of transistors operating in a common base configuration. The base electrodes of each of the transistors is coupled to a common conductor rail line that maintains the collector currents in the transistors temperature compensated over a wide range of operating temperatures during normal operation power-up mode of the receiver. In a standby mode of the receiver, power dissipation in the transistors is reduced by applying an on/off control signal to the common conductor rail line that prevents the flow of the collector currents in each of the transistors. Consequently, the supply current requirement of the control circuit is reduced during the standby mode.
    Type: Grant
    Filed: April 24, 1987
    Date of Patent: April 12, 1988
    Assignee: RCA Corporation
    Inventors: Robert L. Shanley, II, Jack Craft, Michael L. Low, Jeffery B. Lendaro
  • Patent number: 4737694
    Abstract: In a video display apparatus, the high voltage generating circuitry responds to trigger pulses derived from horizontal deflection retrace-related pulses. During normal horizontal deflection operation, the trigger pulses produced are of sufficient amplitude to cause normal triggering of the high voltage generating circuits resulting in normal high voltage levels being produced. Under abnormal horizontal deflection operation in which the horizontal deflection current is not produced, the trigger pulses will be of insufficient amplitude to trigger the high voltage generating circuit, and hence no high voltage level is produced.
    Type: Grant
    Filed: November 4, 1986
    Date of Patent: April 12, 1988
    Assignee: RCA Corporation
    Inventor: Wolfgang F. W. Dietz
  • Patent number: 4734771
    Abstract: A supply voltage is developed in accordance with an on/off control signal of a remote receiver during a start-up interval and during a power-up mode of operation of a television power supply. During a standby mode of operation, the supply voltage is switched off. The supply voltage produces a supply current in an oscillator that produces a signal at a horizontal rate related frequency. The supply voltage also produces a base drive current in a switching transistor of a horizontal driver only during the start-up interval. During a power-up mode, a run supply voltage is coupled to the oscillator and to the driver.
    Type: Grant
    Filed: April 24, 1987
    Date of Patent: March 29, 1988
    Assignee: RCA Corporation
    Inventors: Jeffery B. Lendaro, Robert L. Shanley, II, Jack Craft, Michael L. Low
  • Patent number: 4731565
    Abstract: A high-voltage stabilizer circuit cooperates with the flyback transformer in a cathode ray tube display system to prevent level variations in the video signal from producing corresponding variations in the high-voltage output from the flyback transformer to the cathode ray tube, such high-voltage variations being undesirable because they result in changes in the electron beam position on the phosphor screen that produce shifts in the resultant picture. The current flowing through the video circuit is controlled inversely in relation to variations in the cathode current of the cathode ray tube so that the high-voltage output from the flyback transformer remains constant. This high-voltage stabilizer involves specific choices of circuit element values and is particularly suitable for so-called flat-tube television receivers.
    Type: Grant
    Filed: September 17, 1985
    Date of Patent: March 15, 1988
    Assignee: Sony Corporation
    Inventors: Susumu Tagawa, Chihiro Miura
  • Patent number: 4728868
    Abstract: A circuit for generating a dc high voltage supplied to an anode of a cathode-ray tube, having a simplified circuit structure and reduced size. A first horizontal deflection circuit applies a first flyback pulse across the primary coil of a flyback transformer, while a second horizontal deflection circuit supplies a second flyback pulse to a lower voltage side of the secondary coil of the flyback transformer through a coupling capacitor. A dc voltage supplied to the second horizontal deflection circuit is controlled in response to the output voltage of the secondary coil of the flyback transformer. A current detection circuit for automatic brightness limiting is coupled to the lower voltage side of the secondary coil of the flyback transformer for detecting changes in the secondary current of the flyback transformer.
    Type: Grant
    Filed: April 20, 1984
    Date of Patent: March 1, 1988
    Assignee: Pioneer Electronic Corporation
    Inventors: Katsumi Ishikawa, Nobuhiko Saegusa
  • Patent number: 4727464
    Abstract: An arrangement in which the horizontal deflection circuit with deflection winding, driver circuit and storage inductance are associated with a side linked with the network, whereas the windings for production of high and operational voltage as well as the horizontal oscillator with phase comparator and the vertical deflection coil, together with their trigger circuits are separated or isolated from the network. The regulating information for the regulation of the circuit network part mounted on the side linked to the network is taken from a regulation circuit separate from the network and transmitted by way of a network-separating combining circuit.
    Type: Grant
    Filed: November 4, 1986
    Date of Patent: February 23, 1988
    Assignee: Deutsche Thomson-Brandt GmbH
    Inventors: Uwe Hartmann, Udo Mai
  • Patent number: 4714871
    Abstract: A level shifter receives a variable input voltage such as a beam current representative voltage of a cathode ray tube and produces an output voltage that changes when the input voltage changes such that the output voltage is level shifted relative to the input voltage. The output voltage is coupled to an input terminal of an error amplifier of a power supply voltage regulator of a television receiver. The level shifter includes a current mirror arrangement responsive to the input voltage. A band gap type voltage source determines the amount of level shifting that is produced by the level shifter.
    Type: Grant
    Filed: December 18, 1986
    Date of Patent: December 22, 1987
    Assignee: RCA Corporation
    Inventors: Jack Craft, Michael L. Low, Bernard J. Yorkanis