Light tube and power supply circuit
First Claim
1. A replacement light tube for replacing a fluorescent light tube, comprising:
- a bulb portion having a first end and a second end;
a first end cap and a second end cap disposed at the first end and the second end, respectively, each configured to fit with a socket for the fluorescent light tube;
a plurality of light emitting diodes disposed inside and extending between the first and second ends of the bulb portion, wherein the plurality of light emitting diodes are arranged to provide light through at least a portion of the bulb portion;
a pulse width modulator configured to receive power from a power source and modulate the received power to one of a first brightness level and a second brightness level, the second brightness level being different than the first brightness level; and
a current limiter comprising an inductive element coupled between the pulse width modulator and at least some of the plurality of light emitting diodes.
2 Assignments
0 Petitions
Accused Products
Abstract
A replacement light tube for replacing a fluorescent light tube includes a bulb portion having a first end and a second end, a first end cap and a second end cap disposed at the first end and the second end, respectively, each configured to fit with a socket for the fluorescent light tube, a plurality of light emitting diodes disposed inside and extending between the first and second ends of the bulb portion, a pulse width modulator configured to receive power from a power source and modulate the received power to one of a first brightness level and a second brightness level, the second brightness level being different than the first brightness level and a current limiter comprising an inductive element coupled between the pulse width modulator and at least some of the plurality of light emitting diodes.
-
Citations
30 Claims
-
1. A replacement light tube for replacing a fluorescent light tube, comprising:
-
a bulb portion having a first end and a second end; a first end cap and a second end cap disposed at the first end and the second end, respectively, each configured to fit with a socket for the fluorescent light tube; a plurality of light emitting diodes disposed inside and extending between the first and second ends of the bulb portion, wherein the plurality of light emitting diodes are arranged to provide light through at least a portion of the bulb portion; a pulse width modulator configured to receive power from a power source and modulate the received power to one of a first brightness level and a second brightness level, the second brightness level being different than the first brightness level; and a current limiter comprising an inductive element coupled between the pulse width modulator and at least some of the plurality of light emitting diodes. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A replacement light tube for replacing a fluorescent light tube, comprising:
-
a housing having a first end and a second end; a first end cap and a second end cap disposed at the first end and the second end, respectively, each configured to fit with a socket for the fluorescent light tube; a rigid support structure having a planar portion having a first surface extending within the housing between the first end and the second end and having spaced-apart sidewalls extending away from the first surface and extending within the housing between the first end and the second end, at least a portion of the sidewalls in contact with an interior surface of the housing; a plurality of light emitting diodes supported by a second surface of the planar portion opposite to the first surface and extending between the first and second ends of the housing, wherein the plurality of light emitting diodes are arranged to provide light through at least a portion of the housing; and power supply circuitry configured to receive power from a power source and modulate the received power to one of a first brightness level and a second brightness level, the second brightness level being different than the first brightness level. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A method for operating a replacement light tube for replacing a fluorescent light tube, the replacement light tube including:
-
a bulb portion having a first end and a second end; a first end cap and a second end cap disposed at the first end and the second end, respectively, each configured to fit with a socket for the fluorescent light tube; a plurality of light emitting diodes disposed inside and extending between the first and second ends of the bulb portion; and power supply circuitry having a pulse-width modulator and a current limiting circuit including an inductive element coupled between pulse-width modulator and at least some of the plurality of light emitting diodes, the method comprising; receiving power from a power source; and modulating, using the pulse-width modulator, the received power to one of a first brightness level and a second brightness level, the second brightness level being different than the first brightness level. - View Dependent Claims (19, 20, 21, 22, 23, 24)
-
-
25. A replacement light tube for replacing a fluorescent light tube, the replacement light tube configured to emit white light at a plurality of brightness levels, comprising:
-
a housing having a first end and a second end; a first end cap and a second end cap disposed at the first end and the second end, respectively, each configured to fit with a socket for the fluorescent light tube; a plurality of light emitting diodes disposed inside and extending between the first and second ends of the housing, wherein the plurality of light emitting diodes are arranged to provide light through at least a portion of the housing; a pulse width modulator configured to; receive power from a power source, in response to a first user adjustment, modulate the received power to a first one of the plurality of brightness levels, and in response to a second user adjustment, modulate the received power to a second one of the plurality of brightness levels, wherein the second brightness level is different than the first brightness level; and a current limiter comprising an inductive element coupled between the pulse width modulator and at least some of the plurality of light emitting diodes. - View Dependent Claims (26, 27, 28, 29, 30)
-
Specification