US3896336A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solid state fluorescent lamp ballast system
Assignee: Texas Instruments Inc
•
Filing: 1973-12-20
•
Granted: 1975-07-22
•
Expires: 1993-12-20
Abstract
Abstract An improved solid-state fluorescent lamp ballast in which line voltage or directly rectified line voltage is chopped to provide a high frequency input to the lamp permitting smaller reactive ballast components to be used. Also shown are various means of switching, means for isolating the high voltage switches for the logic circuits, driving them and various load circuits.
Inventors
- 👤 Max P Schreiner
- 👤 Tom M Hyltin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:03
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/282; Y; Y02; Y02B; Y02B20/00; Y10; Y10S; Y10S315/00; Y10S315/07
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
135 words
A solid-state fluorescent lamp ballast circuit system comprising: a gaseous discharge lamp; full-wave rectifying means for supplying a pulsating voltage; a first switch coupling one side of the output of said rectifying means to one side of said lamp; a second switch coupling said one rectifying means side to the other side of said lamp; a third switch coupling the other side of said rectifying means to said one side of said lamp; a fourth switch coupling said other side of said rectifying means to said other side of said lamp; trigger means for providing first and second complementary pulse trains, said first pulse train being coupled to said first and fourth switches, said second pulse trains being coupled to said second and third switches; and reactive means coupling said switching means to said lamp.
Claim 2
Dependent Claim
135 words
A solid-state fluorescent lamp ballast circuit system comprising: a gaseous discharge lamp; full-wave rectifying means for supplying a pulsating voltage; a first switch coupling one side of the output of said rectifying means to one side of said lamp; a second switch coupling said one rectifying means side to the other side of said lamp; a third switch coupling the other side of said rectifying means to said one side of said lamp; a fourth switch coupling said other side of said rectifying means to said other side of said lamp; trigger means for providing first and second complementary pulse trains, said first pulse train being coupled to said first and fourth switches, said second pulse trains being coupled to said second and third switches; and reactive means coupling said switching means to said lamp.
Claim 3
Dependent Claim
18 words
The invention according to claim 1 wherein said first, second, third and fourth switches comprise gate controlled switches.
Claim 4
Dependent Claim
20 words
The invention according to claim 1 wherein said first, second, third and fourth switches comprise regenerative bistable latch type devices.
Claim 5
Dependent Claim
24 words
The invention according to claim 1 wherein said first and second switches comprise gate controlled switches and said third and fourth switches comprise transistors.
Claim 6
Dependent Claim
26 words
The invention according to claim 1 wherein said first and second switches comprise regernative bistable latch type devices and said third and fourth switches comprise transistors.
Claim 7
Dependent Claim
16 words
The invention according to claim 1 wherein said first, second, third and fourth switches comprise transistors.
Claim 8
Dependent Claim
22 words
The invention according to claim 6 wherein each of said first, second, third and fourth switches comprises a Darlington pair of transistors.
Claim 9
Dependent Claim
33 words
The invention according to claim 1 and further including high voltage isolation means between at least said first and second switches and said first and second output pulse trains from said trigger means.
Claim 10
Dependent Claim
12 words
The inventioN according to claim 8 wherein said isolation means comprise transformers.
Claim 11
Dependent Claim
14 words
The invention according to claim 9 wherein said isolation means comprise optical isolation means.
Claim 12
Dependent Claim
40 words
The invention according to claim 10 wherein said optical isolation means comprise: a. A light emitting diode coupled to one of said pulse trains; and b. a photo transistor adjacent to said diode and coupled to one of said switches.
Claim 13
Dependent Claim
15 words
The invention according to claim 8 wherein said isolation means comprises a level shifter transistor.
Claim 14
Dependent Claim
55 words
The invention according to claim 1 wherein said ballast reactance comprises an inductor selected to limit the current to said lamp and further including a capacitor shunted across said lamp said capacitor selected to form a tuned circuit with said inductor which has a resonance near the frequency of the output of said trigger means.
Claim 15
Dependent Claim
32 words
The invention according to claim 1 wherein said first and second pulse trains have alternating on periods which are separated by a period when both pulse trains are in an off period.
References Cited (Backward Citations)
US3292040A
Cited
US3299320A
Cited
US3482142A
Cited
US3659150A
Cited
US3621331A
Cited
US3657598A
Cited
US3793557A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-21 | 1979-01-20 | 1979-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-21 | 1983-01-20 | 1983-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-21 | 1987-01-20 | 1987-07-22 | $7700.00 | Window Closed / Lapsed |