US3573544A - A gas discharge lamp circuit employing a transistorized oscillator - Google Patents
A gas discharge lamp circuit employing a transistorized oscillator Download PDFInfo
- Publication number
- US3573544A US3573544A US835864A US3573544DA US3573544A US 3573544 A US3573544 A US 3573544A US 835864 A US835864 A US 835864A US 3573544D A US3573544D A US 3573544DA US 3573544 A US3573544 A US 3573544A
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- tube
- frequency
- transformer
- starting
- operating
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- 238000004804 winding Methods 0.000 claims description 58
- 239000003990 capacitor Substances 0.000 claims description 52
- 230000008878 coupling Effects 0.000 claims description 4
- 238000010168 coupling process Methods 0.000 claims description 4
- 238000005859 coupling reaction Methods 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 238000005286 illumination Methods 0.000 description 4
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 241001657674 Neon Species 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
- H05B41/14—Circuit arrangements
- H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
- H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
- H05B41/282—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices
- H05B41/2821—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices by means of a single-switch converter or a parallel push-pull converter in the final stage
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S315/00—Electric lamp and discharge devices: systems
- Y10S315/04—Dimming circuit for fluorescent lamps
Definitions
- the present invention relates generally to lighting circuits and more specifically to an improved circuit which increases the efficiency of gas-filled tubes both in the starting and the operating phases as well as the life expectancy of the tube it self.
- gas-tilled tubes include fluorescent tubes, utlraviolet, rare gas tubes such as neons, and vapor devices such as mercury vapor, sodium vapor and the like. The ensuing description will be directed to the application of the circuit to fluorescent lamps with the understanding that the principle of operation with other gas-filled tubes will be the same.
- the particular advantage of the circuit of the present invention is that it provides a means for operating fluorescent lamps with less power input for the same light output, or conversely, at the same power input, brighter illumination is obtained.
- Another advantage is that the life of the tube is not effected by the number of times ionization is started. For example, manufacturers rate fluorescent tubes in terms of operating hours and number of starts. On a hot cathode tube rated at 7,500 hour lifetime, the maximum number of starts to be expected is about 2,500. A cold cathode tube may be rated at 15,000 to 30,000 hours with an almost indefinite number of starts, but operates at much lower efficiency than the hot cathode type and is not in general use. With the circuit of the present design in excess of 5,000 starts have been obtained with a hot cathode-type tube without a noticeable decrease in the operating performance of the tube.
- the reason circuits heretofore proposed have failed to obtain the efficiency of the present circuit is the failure to properly deal with the complex variable impedance of gasfilled tubes.
- the tube impedance is made a very definite part of the secondary circuit and is considered as an ohmic value. Taking the ohmic value of a' specific tube, the values of the other circuit elements are then determined and a well-matched resonant circuit is provided for maximum efficiency with that specific tube.
- the same circuit will operate other tubes of different size or power requirements but not as efficiently as for the specific tube for which it was designed. It has been found that manufacturers specifications are sufficiently strict so that tubes having the same manufacturers specifications will have very nearly the same mpsdans t lt is an object therefore of the present invention to provide an improved circuit for the operation of gas-filled tubes.
- lt is also an object of the present invention to provide a gasfilled tube circuit having decreased starting time.
- FIG. 1 is a schematic circuit diagram of a preferred embodiment of the circuit of the present invention.
- FIG. 2 is a graph representing performance characteristics of the circuit.
- a transistor 10 is connected as a typical oscillator in which the emitter 11 is connected to the negative electrode 12 of battery 13 through switch 35.
- Emitter 11 may be directly connected to electrode 12 through switch 35 or through variable resistor 14 and capacitor 15 if it is desired that there be a means for adjusting the input voltage to the circuit.
- Zener diode 16 is connected between emitter 11 and collector 1'7 of transistor 10 to guard against excessive peak inverse voltages as when the tube is broken, etc.
- Collector 17 also connected to terminal 13 of the primary winding of transformer 19.
- the positive electrode 20 of battery 13 is coupled to tap 21 of transformer 19.
- a diode 22 may be connected in series with positive electrode 20 to prevent damage to the circuit should the connections to the battery 13 be inadvertently reversed.
- Capacitor 23 may be connected across the series combination of the battery 13 and diode 22 with the polarity shown in instance where the battery 13 may be located some distances from the oscillator circuit in which case the leads would inject some unwanted inductance into the oscillator circuit. Capacitor 23 is thus selected having a value to compensate for any inductance added by the battery leads.
- Battery 13 is connected through a base circuit impedance to the base 24 of transistor 10.
- the base 24 is connected through capacitor 25 to terminal 26 of the feedback winding of transformer 19.
- a feedback resistor 27 is connected between tap 21 and base electrode 24 and a bypass capacitor 28 is coupled across resistor 27.
- the base circuit impedance includes resistor 27 and capacitor 25 and 28. Capacitor 28 is selected having a value such that it will protect the base 24 of transistor 10 from peaks occurring in the oscillator circuit.
- the secondary winding 29 of transformer 19 has a capacitor 30 coupled in parallel between terminals 31 and 32 thereof.
- Another capacitor 33 is connected in series with terminal 31 and fluorescent tube 34 which is in turn connected to terminal 32 of transformer 19.
- Capacitor 33 will have a value which is large with respect to that of capacitor 30 and thus the high voltage appearing across terminals 31 and 32 will be impressed across the terminals of fluorescent tube 34 as shown by FIG. 2 at the portion designated 36 of the voltage curve 37.
- the high frequency at this stage is shown at 30 on frequency curve 39 in FIG. 2.
- the combination of high voltage and high frequency impressed upon tube 34 will rapidly initiate a glow discharge-type of ionization within the tube. This ionization will cause current to start flowing through tube 34 as shown by the lower portion 40 of current curve 41 in FIG. 2.
- the circuit operates in two phases, a starting phase characterized by high frequency and high voltage, followed by an operating phase characterized by having relatively low voltage and high current with an operating frequency less than the starting frequency.
- a starting phase characterized by high frequency and high voltage
- an operating phase characterized by having relatively low voltage and high current with an operating frequency less than the starting frequency.
- a standard single-pin fluorescent tube manufactured by Sylvania having a code No. F24Tl2, COOL-WHITE was first connected in a conventional fixture operating at an input voltage of l volts at 60 cycles. This is a 26 watt tube and it provided a light reading of approximately 1,1000 lumens. The same 26 watt tube was then coupled into the circuit made in accordance with this invention in which the input voltage wasv 36 volts. Operating again at an input power of 26 watts, the tube started at a frequency of approximately 150 kc. and after starting provided a light output of approximately 1,600 lumens. After starting, current input was 710 ma. at 42 kc. This represents a percentage increase in light output of approximately 45 percent. In a similar manner, the power input may be reduced 45 percent to about 14.3 watts and still produce the same 1,100 lumens of light output obtained by the conventional circuit.
- the circuit of the present invention provides a unique method of operating fluorescent tubes which obtains greater illumination therefrom for a given input power while at the same time prolonging the operating life thereof. While a particular embodiment of this circuit has been shown and described, it will be obvious to persons skilled in the art that changes and modifications might be made, particularly as to the type oscillator circuit used, without departing from the invention in its broader aspects. It is the aim of the appended claims to cover all such changes and modifications as fall within the true scope and spirit of this invention.
- a system for starting and operating a gas-filled tube comprising: an oscillator circuit adapted for connection to a source of electrical potential, said oscillator circuit having a starting mode characterized by a starting frequency and an operating mode characterized by an operating frequency; a transformer connected into and forming a part of said oscillator circuit, said transformer having a primary and a secondary winding,-said starting frequency being at least in part determined by the transformer; a load circuit connected across said secondary winding, said load circuit consisting of capacitor means and a gas-filled tube connected in series circuit relationship so the capacitor means is decoupled from the transformer when the gas-filled tube is nonconductive; the secondary winding of said transformer being related to the primary winding so as to develop across the secondary winding as soon as said oscillator is energized a high frequency voltage of sufficient magnitude which automatically initiates a glow discharge type of ionization within said tube during said starting mode; and said operating frequency being substantially altered by said capacitor means when the gas tube is conductive.
- said oscillator circuit includes: a transistor having a collector, an emitter and a base, said source of electric potential being connected in proper biasing relationship across said emitter and said base and being connected through said collector and said emitter across said primary winding of said transformer, said transformer including a feedback winding connected between said source of electric potential and said base of said transistor, and a base circuit impedance connected between said feedback winding and said base of said transistor for controlling the voltage and current applied to said base.
- said base circuit impedance includes a feedback resistor and a bypass capacitor connected in parallel between said base and said source of electric potential, and a capacitor connected between said base and said feedback winding.
- a system for starting and operating a gas-filled tube comprising: an oscillator circuit including current control device means adapted for connection to a source of electrical potential, said oscillator circuit having a starting mode characterized by a starting frequency and an operating mode characterized by an operating frequency; a transformer connected into and forming a part of said oscillator circuit, said transformer having primary, secondary and feedback winding means; an output circuit connected across said secondary winding, said output circuit including capacitor means and a gas-filled tube connected in series circuit relationship so the capacitor is decoupled from the transformer when the gasfilled tube is nonconductive; the primary, secondary and feedback winding means of said transformer being related to the current control device means to form an oscillator circuit which develops across the secondary winding means a high starting voltage of sufficient magnitude to initiate a glow discharge type of ionization within said tube during said starting mode; and said operating frequency being a frequency substantially different from said starting frequency due to the coupling to said transformer of said capacitor means when the gas tube is conductive; said operating frequency being selected to provide maximum output efficiency from
- a system for starting and operating a gas-filled tube comprising: a transformer having primary and secondary windings and a load circuit consisting of capacitor means and a gasfillcd tube connected in series circuit relationship with said secondary winding, means connected to said transformer for driving said secondary winding in a starting mode having a characteristic starting frequency which automatically ionizes the gas in said tube as soon as said secondary winding is so driven and in an operating mode having a characteristic operating frequency to provide alternating current to said tube, and a source of electric potential connected to said driving means.
- a system for starting and operating a gas-filled tube comprising: an oscillator circuit including current control device means adapted for connection to a source of electrical potential, said oscillator circuit having a starting mode characterized by a starting frequency and an operating mode characterized by an operating frequency; a transformer connected into and forming a part of said oscillator circuit, said transformer having primary, secondary and feedback winding means; an output circuit connected across said secondary winding, said output circuit including capacitor means and a gas-filled tube connected in series circuit relationship so the capacitor is decoupled from the transformer when the gasfilled tube is nonconductive; the primary, secondary and feed back winding means of said transformer being related to the current control device means to form an oscillator circuit which develops across the secondary winding means a high starting frequency voltage of sufficient magnitude to initiate a glow discharge type of ionization within said tube during said starting mode; and said operating frequency being a frequency substantially different from said starting frequency due to the coupling to said transformer of said capacitor means when the gas tube is conductive, said operating frequency being determined at least
Abstract
Description
Claims (13)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US83586469A | 1969-05-21 | 1969-05-21 |
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US3573544A true US3573544A (en) | 1971-04-06 |
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US835864A Expired - Lifetime US3573544A (en) | 1969-05-21 | 1969-05-21 | A gas discharge lamp circuit employing a transistorized oscillator |
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Cited By (26)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4860235A (en) * | 1971-11-30 | 1973-08-23 | ||
US3818312A (en) * | 1971-09-17 | 1974-06-18 | Philips Corp | Dc-ac converter |
US3922582A (en) * | 1974-08-22 | 1975-11-25 | Gte Sylvania Inc | Current limited oxcillator arrangement |
US4029993A (en) * | 1975-12-18 | 1977-06-14 | General Electric Company | Two level inverter circuit |
FR2398427A1 (en) * | 1977-07-19 | 1979-02-16 | Legrand Sa | Supply circuit for fluorescent security light - has transformer and variable frequency DC=AC converter with adjustable saturation characteristics |
US4172981A (en) * | 1978-06-15 | 1979-10-30 | Francis H. Harrington | Lighting system |
US4207497A (en) * | 1978-12-05 | 1980-06-10 | Lutron Electronics Co., Inc. | Ballast structure for central high frequency dimming apparatus |
US4228382A (en) * | 1978-01-09 | 1980-10-14 | Teknoware Oy | Power regulating inverter circuit |
US4286194A (en) * | 1977-12-05 | 1981-08-25 | Sherman Eli H | Generator for use with loads having changing impedance characteristics |
DE3208607A1 (en) | 1981-03-12 | 1982-12-16 | Zumtobel AG, 6850 Dornbirn | Ballast apparatus for at least one load which is triggered and supplied periodically by means of a generator |
FR2520575A1 (en) * | 1982-01-26 | 1983-07-29 | Thomson Brandt Gmbh | SUPPLY CIRCUIT FOR A LUMINESCENT TUBE |
US4686427A (en) * | 1985-08-13 | 1987-08-11 | Magnetek, Inc. | Fluorescent lamp dimming switch |
FR2595531A1 (en) * | 1986-03-06 | 1987-09-11 | Naudy Annick | Device for supplying electrical power to a low-power fluorescent tube and a method of using such a device |
DE3715162A1 (en) * | 1987-05-07 | 1988-11-17 | Bosch Gmbh Robert | CIRCUIT ARRANGEMENT FOR OPERATING A GAS DISCHARGE LAMP ON A DC POWER SOURCE |
US4806830A (en) * | 1985-10-29 | 1989-02-21 | Kabushiki Kaisha Denkosha | Device and process for lighting a fluorescent discharge lamp |
US5039920A (en) * | 1988-03-04 | 1991-08-13 | Royce Electronic Products, Inc. | Method of operating gas-filled tubes |
US5204587A (en) * | 1991-02-19 | 1993-04-20 | Magnetek, Inc. | Fluorescent lamp power control |
US5239239A (en) * | 1992-03-26 | 1993-08-24 | Stocker & Yale, Inc. | Surrounding a portion of a lamp with light regulation apparatus |
US5345150A (en) * | 1992-03-26 | 1994-09-06 | Stocker & Yale, Inc. | Regulating light intensity by means of magnetic core with multiple windings |
US5446342A (en) * | 1985-11-06 | 1995-08-29 | Nilssen; Ole K. | Light-output-controlled fluorescent lighting fixture |
US5796216A (en) * | 1993-07-16 | 1998-08-18 | Delta Power Supply, Inc. | Electronic ignition enhancing circuit having both fundamental and harmonic resonant circuits as well as a DC offset |
US5914571A (en) * | 1996-09-03 | 1999-06-22 | Delta Power Supply, Inc. | Method for igniting high frequency operated, high intensity discharge lamps |
US20070145909A1 (en) * | 1999-06-21 | 2007-06-28 | Access Business Group International Llc | Inductively-powered gas discharge lamp circuit |
US20080151580A1 (en) * | 1997-01-24 | 2008-06-26 | Schlecht Martin F | High efficiency power converter |
US7558083B2 (en) | 1997-01-24 | 2009-07-07 | Synqor, Inc. | High efficiency power converter |
US10199950B1 (en) | 2013-07-02 | 2019-02-05 | Vlt, Inc. | Power distribution architecture with series-connected bus converter |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2923856A (en) * | 1958-10-02 | 1960-02-02 | Gilbert Associates | High frequency ballast unit |
US2964676A (en) * | 1957-08-29 | 1960-12-13 | Gen Electric Co Ltd | Circuit arrangements for operating low pressure electric discharge lamps |
US3005130A (en) * | 1958-11-21 | 1961-10-17 | Samuel A Schwartz | Fluorescent lighting system |
US3084283A (en) * | 1959-04-30 | 1963-04-02 | Philips Corp | Transistor-battery supply for gas-discharge tubes |
US3371244A (en) * | 1965-02-08 | 1968-02-27 | Ultra Violet Products Inc | Ultraviolet lamp transformer |
US3396307A (en) * | 1967-04-17 | 1968-08-06 | Gen Electric | Transistor inverter lamp ballasting circuit |
-
1969
- 1969-05-21 US US835864A patent/US3573544A/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
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US2964676A (en) * | 1957-08-29 | 1960-12-13 | Gen Electric Co Ltd | Circuit arrangements for operating low pressure electric discharge lamps |
US2923856A (en) * | 1958-10-02 | 1960-02-02 | Gilbert Associates | High frequency ballast unit |
US3005130A (en) * | 1958-11-21 | 1961-10-17 | Samuel A Schwartz | Fluorescent lighting system |
US3084283A (en) * | 1959-04-30 | 1963-04-02 | Philips Corp | Transistor-battery supply for gas-discharge tubes |
US3371244A (en) * | 1965-02-08 | 1968-02-27 | Ultra Violet Products Inc | Ultraviolet lamp transformer |
US3396307A (en) * | 1967-04-17 | 1968-08-06 | Gen Electric | Transistor inverter lamp ballasting circuit |
Non-Patent Citations (1)
Title |
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Japanese Utility Model Publication No. 21137/1962, Published July 15, 1961 Devisers: Takeshi Hirasawa & Enomoto. Copy in Library * |
Cited By (35)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3818312A (en) * | 1971-09-17 | 1974-06-18 | Philips Corp | Dc-ac converter |
JPS547922B2 (en) * | 1971-11-30 | 1979-04-11 | ||
JPS4860235A (en) * | 1971-11-30 | 1973-08-23 | ||
US3922582A (en) * | 1974-08-22 | 1975-11-25 | Gte Sylvania Inc | Current limited oxcillator arrangement |
US4029993A (en) * | 1975-12-18 | 1977-06-14 | General Electric Company | Two level inverter circuit |
FR2398427A1 (en) * | 1977-07-19 | 1979-02-16 | Legrand Sa | Supply circuit for fluorescent security light - has transformer and variable frequency DC=AC converter with adjustable saturation characteristics |
US4286194A (en) * | 1977-12-05 | 1981-08-25 | Sherman Eli H | Generator for use with loads having changing impedance characteristics |
US4228382A (en) * | 1978-01-09 | 1980-10-14 | Teknoware Oy | Power regulating inverter circuit |
US4172981A (en) * | 1978-06-15 | 1979-10-30 | Francis H. Harrington | Lighting system |
US4207497A (en) * | 1978-12-05 | 1980-06-10 | Lutron Electronics Co., Inc. | Ballast structure for central high frequency dimming apparatus |
DE3208607A1 (en) | 1981-03-12 | 1982-12-16 | Zumtobel AG, 6850 Dornbirn | Ballast apparatus for at least one load which is triggered and supplied periodically by means of a generator |
FR2520575A1 (en) * | 1982-01-26 | 1983-07-29 | Thomson Brandt Gmbh | SUPPLY CIRCUIT FOR A LUMINESCENT TUBE |
US4686427A (en) * | 1985-08-13 | 1987-08-11 | Magnetek, Inc. | Fluorescent lamp dimming switch |
US4806830A (en) * | 1985-10-29 | 1989-02-21 | Kabushiki Kaisha Denkosha | Device and process for lighting a fluorescent discharge lamp |
US5446342A (en) * | 1985-11-06 | 1995-08-29 | Nilssen; Ole K. | Light-output-controlled fluorescent lighting fixture |
FR2595531A1 (en) * | 1986-03-06 | 1987-09-11 | Naudy Annick | Device for supplying electrical power to a low-power fluorescent tube and a method of using such a device |
DE3715162A1 (en) * | 1987-05-07 | 1988-11-17 | Bosch Gmbh Robert | CIRCUIT ARRANGEMENT FOR OPERATING A GAS DISCHARGE LAMP ON A DC POWER SOURCE |
US5039920A (en) * | 1988-03-04 | 1991-08-13 | Royce Electronic Products, Inc. | Method of operating gas-filled tubes |
US5204587A (en) * | 1991-02-19 | 1993-04-20 | Magnetek, Inc. | Fluorescent lamp power control |
US5239239A (en) * | 1992-03-26 | 1993-08-24 | Stocker & Yale, Inc. | Surrounding a portion of a lamp with light regulation apparatus |
US5345150A (en) * | 1992-03-26 | 1994-09-06 | Stocker & Yale, Inc. | Regulating light intensity by means of magnetic core with multiple windings |
US5796216A (en) * | 1993-07-16 | 1998-08-18 | Delta Power Supply, Inc. | Electronic ignition enhancing circuit having both fundamental and harmonic resonant circuits as well as a DC offset |
US5914571A (en) * | 1996-09-03 | 1999-06-22 | Delta Power Supply, Inc. | Method for igniting high frequency operated, high intensity discharge lamps |
US7564702B2 (en) | 1997-01-24 | 2009-07-21 | Synqor, Inc. | High efficiency power converter |
US20080151580A1 (en) * | 1997-01-24 | 2008-06-26 | Schlecht Martin F | High efficiency power converter |
US7558083B2 (en) | 1997-01-24 | 2009-07-07 | Synqor, Inc. | High efficiency power converter |
US8023290B2 (en) | 1997-01-24 | 2011-09-20 | Synqor, Inc. | High efficiency power converter |
US8493751B2 (en) | 1997-01-24 | 2013-07-23 | Synqor, Inc. | High efficiency power converter |
US9143042B2 (en) | 1997-01-24 | 2015-09-22 | Synqor, Inc. | High efficiency power converter |
US20070145909A1 (en) * | 1999-06-21 | 2007-06-28 | Access Business Group International Llc | Inductively-powered gas discharge lamp circuit |
US7592753B2 (en) * | 1999-06-21 | 2009-09-22 | Access Business Group International Llc | Inductively-powered gas discharge lamp circuit |
US10199950B1 (en) | 2013-07-02 | 2019-02-05 | Vlt, Inc. | Power distribution architecture with series-connected bus converter |
US10594223B1 (en) | 2013-07-02 | 2020-03-17 | Vlt, Inc. | Power distribution architecture with series-connected bus converter |
US11075583B1 (en) | 2013-07-02 | 2021-07-27 | Vicor Corporation | Power distribution architecture with series-connected bus converter |
US11705820B2 (en) | 2013-07-02 | 2023-07-18 | Vicor Corporation | Power distribution architecture with series-connected bus converter |
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