US5138236A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit for driving a gas discharge lamp load
Assignee: MOTOROLA LIGHTING, INC., A CORP. OF DE
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Filing: 1991-05-28
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Granted: 1992-08-11
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Expires: 2011-05-28
Abstract
Abstract A circuit (100) for driving fluorescent lamps (102, 104, 106) and including: a half-bridge inverter (112) receiving a unidirectional voltage and producing an alternating voltage, and having control inputs (156, 166); a series-resonant oscillator (126) coupled to the inverter output (116) for producing an alternating signal; and a non-saturating feedback transformer (146) having a primary winding (148) coupled in series between the inverter and the oscillator and secondary winding (150, 152) coupled respectively to the control inputs of the inverter. Since the feedback transformer is non-saturating it provides to the inverter control inputs a linear feedback signal from the inverter. This results in safe, stable, predictable and well-defined circuit operation, in which the possibility of the inverter transistors being destroyed by cross-conduction is substantially removed, and the amount of input voltage "ripple" present in the signal applied to the lamps is reduced.
Inventors
- 👤 Andrew Bobel
- 👤 Mihail S. Moisin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:57
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/38; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/282; H05B41/2825; H05B41/2827; Y; Y10; Y10S; Y10S315/00; Y10S315/07
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
201 words
A circuit for driving a gas discharge lamp load, the circuit comprising: inverter means having an input for receiving a unidirectional voltage and an output for producing an alternating voltage, the inverter means including a first transistor switch means and a second transistor switch means coupled in series to the input, the first transistor switch mean shaving a first control input for controlling the switching of the first transistor switch means, and the second transistor switch means having a second control input for controlling the switching of the second transistor switch means; resonant oscillator means coupled to the output of the inverter means, and including an inductance and a capacitance coupled for producing an alternating signal; feedback transformer means coupled to the resonant oscillator means and to the first and second control inputs; first resistance means coupled serially between the feedback transformer means and the first control input and second resistance means coupled serially between the feedback transformer means and the second control input, the feedback transformer means providing to the first and second control inputs via the first and second resistance means signals which vary linearly with the alternating signal of the resonant oscillator means in operation of the circuit.
Claim 2
Dependent Claim
201 words
A circuit for driving a gas discharge lamp load, the circuit comprising: inverter means having an input for receiving a unidirectional voltage and an output for producing an alternating voltage, the inverter means including a first transistor switch means and a second transistor switch means coupled in series to the input, the first transistor switch mean shaving a first control input for controlling the switching of the first transistor switch means, and the second transistor switch means having a second control input for controlling the switching of the second transistor switch means; resonant oscillator means coupled to the output of the inverter means, and including an inductance and a capacitance coupled for producing an alternating signal; feedback transformer means coupled to the resonant oscillator means and to the first and second control inputs; first resistance means coupled serially between the feedback transformer means and the first control input and second resistance means coupled serially between the feedback transformer means and the second control input, the feedback transformer means providing to the first and second control inputs via the first and second resistance means signals which vary linearly with the alternating signal of the resonant oscillator means in operation of the circuit.
Claim 3
Dependent Claim
14 words
A circuit according to claim 1 wherein the inverter means comprises a half-bridge inverter.
Claim 4
Dependent Claim
16 words
A circuit according to claim 1 wherein the resonant oscillator means comprises a series-resonant tank circuit.
Claim 5
Dependent Claim
18 words
A circuit according to claim 1 wherein the first and second transistor switch means comprise bipolar npn transistors.
Claim 6
Dependent Claim
31 words
A circuit according to claim 1 further comprising first diode means coupled in parallel with the first resistance means and second diode means coupled in parallel with the second resistance means.
Claim 7
Dependent Claim
45 words
A circuit according to claim 1 wherein transformer means comprises a primary winding connected in series between the inverter means and the resonant oscillator means, a first secondary winding coupled to the first control input and second secondary winding coupled to the second control input.
Claim 8
Dependent Claim
15 words
A circuit according to claim 1 wherein the feedback transformer means comprises a gapped transformer.
Claim 9
Dependent Claim
14 words
A circuit according to claim 1 wherein the feedback transformer comprises an "E"-shaped core.
Claim 10
Dependent Claim
14 words
A circuit according to claim 1 wherein the feedback transformer comprises a "U"-shaped core.
Claim 11
Dependent Claim
186 words
A circuit for driving a gas discharge lamp load, the circuit comprising: half-bridge inverter means having an input for receiving a unidirectional voltage and an output for producing an alternating voltage, the inverter means including a first transistor switch means and a second transistor switch means coupled in series to the input, the first transistor switch means having a first control input for controlling the switching of the first transistor switch means, and the second transistor switch means having a second control input for controlling the switching of the second transistor switch means; and series-resonant oscillator means coupled to the output of the inverter means, and including an inductance and a capacitance coupled for producing an alternating signal; and feedback transformer means having a primary winding connected between the inverter means and the resonant oscillator means, a first secondary winding coupled to the first control input and second secondary winding coupled to the second control input, the feedback transformer means providing to the first and second control inputs signals which vary linearly with the alternating signal of the resonant oscillator means in operation of the circuit.
Claim 12
Dependent Claim
186 words
A circuit for driving a gas discharge lamp load, the circuit comprising: half-bridge inverter means having an input for receiving a unidirectional voltage and an output for producing an alternating voltage, the inverter means including a first transistor switch means and a second transistor switch means coupled in series to the input, the first transistor switch means having a first control input for controlling the switching of the first transistor switch means, and the second transistor switch means having a second control input for controlling the switching of the second transistor switch means; and series-resonant oscillator means coupled to the output of the inverter means, and including an inductance and a capacitance coupled for producing an alternating signal; and feedback transformer means having a primary winding connected between the inverter means and the resonant oscillator means, a first secondary winding coupled to the first control input and second secondary winding coupled to the second control input, the feedback transformer means providing to the first and second control inputs signals which vary linearly with the alternating signal of the resonant oscillator means in operation of the circuit.
References Cited (Backward Citations)
US5047690A
Cited
US4525649A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-11 | 1996-02-10 | 1996-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-11 | 2000-02-10 | 2000-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-11 | 2004-02-10 | 2004-08-11 | $7700.00 | Window Closed / Lapsed |