Electronic Ballast with High Power Factor
First Claim
1. An electronic ballast circuit for a fluorescent lamp, comprising:
- a power circuit that outputs power to the lamp; and
an integrated power supply for a controller circuit;
wherein the power circuit operates with only one switch;
wherein the integrated power supply receives at least a portion of the output power from the power circuit and delivers power to the controller circuit.
1 Assignment
0 Petitions
Accused Products
Abstract
This invention provides an integrated power supply for a controller of an electronic ballast for a fluorescent lamp. The integrated power supply couples output power from the electronic ballast and uses the coupled power to provide power to the controller. In one embodiment, the electronic ballast may include a rectifier for converting an alternating current input voltage into a direct current output voltage, and a circuit including a combined power factor correction (PFC) stage and an inverter, wherein the PFC stage and the inverter share a switch. Also provided is a controller for an electronic ballast. The controller may include a voltage mode or current mode duty ratio controller that controls a duty ratio of a switch of the ballast. The controller and the ballast allow dimming of the fluorescent lamp while maintaining a high power factor.
-
Citations
40 Claims
-
1. An electronic ballast circuit for a fluorescent lamp, comprising:
-
a power circuit that outputs power to the lamp; and an integrated power supply for a controller circuit; wherein the power circuit operates with only one switch; wherein the integrated power supply receives at least a portion of the output power from the power circuit and delivers power to the controller circuit. - View Dependent Claims (4, 5, 6, 7, 8, 9, 11, 17, 18)
-
-
2-3. -3. (canceled)
-
10. (canceled)
-
12-16. -16. (canceled)
-
19-27. -27. (canceled)
-
28. A method of providing power to a fluorescent lamp, comprising:
-
rectifying an alternating current input voltage to produce a direct current voltage; providing the direct current voltage to a power circuit that operates using only one switch to produce output power for the lamp; and using a portion of the output power to provide power to a controller for the power circuit. - View Dependent Claims (29, 30, 31, 32, 33, 38, 39, 40)
-
-
34-37. -37. (canceled)
Specification