Claims
- 1. An ignition and operation control circuit for an electronic ballast comprising:
a ballast microcontroller (200), the ballast microcontroller (200) being responsive to at least one high intensity discharge (HID) lamp feedback signal and generating an HID lamp control signal; a voltage controlled oscillator (VCO) (204), the VCO (204) being responsive to the HID lamp control signal and generating a VCO output signal (246); a driver (206), the driver (206) being responsive to the VCO output signal (246) and generating a high gate signal (248) and a low gate signal (250); a rail voltage output (202), the rail voltage output (202) providing power (252); a first switch (208), the first switch (208) being responsive to the high gate signal (248) and receiving the power (252); a second switch (210), the second switch (210) being responsive to the low gate signal (250) and being operably connected between the first switch (208) and common (300); a parallel capacitive circuit (214), the parallel capacitive circuit (214) having a first end and a second end, the second end operably connected to the common (300); and an inductive circuit (212), the inductive circuit (212) operably connected between the first end of the parallel capacitive circuit (214) and a junction between the first switch (208) and the second switch (210).
- 2. The ignition and operation control circuit of claim 1 wherein the HID lamp feedback signal is an ignition voltage signal (266) and the HID lamp control signal is a sweep signal (240).
- 3. The ignition and operation control circuit of claim 2 further comprising a DC offset circuit (232), the DC offset circuit (232) being operably connected in parallel to the parallel capacitive circuit (214) and being responsive to a sensed inductor current (270) from the inductive circuit (212).
- 4. The ignition and operation control circuit of claim 2 further comprising:
a clamping circuit (230), the clamping circuit (230) being responsive to a sensed inductor current (270) from the inductive circuit (212) and a sensed rail voltage output voltage (276) from the rail voltage output (202); wherein the clamping circuit (230) generates an inductor current control signal (274), the inductive circuit (212) being responsive to the inductor current control signal (274).
- 5. The ignition and operation control circuit of claim 2 wherein the VCO (204) is responsive to the ignition voltage signal (266).
- 6. The ignition and operation control circuit of claim 1 wherein the HID lamp feedback signal is a sensed lamp current signal (264) and the HID lamp control signal is a sweep signal (240).
- 7. The ignition and operation control circuit of claim 1 wherein the HID lamp feedback signals are a sensed rail voltage signal (256), a sensed lamp current signal (264), and a sensed lamp power signal (258), and the HID lamp control signal is a power reference signal (260).
- 8. The ignition and operation control circuit of claim 1 further comprising:
a first operational amplifier (218), the first operational amplifier (218) being responsive to a sensed lamp power signal (258) and a power reference signal (260), and generating a power error signal (262); a second operational amplifier (220), the second operational amplifier (220) being responsive to the power error signal (262) and a sensed lamp current signal (264), and generating a total error signal (242); wherein the HID lamp feedback signals are a sensed rail voltage signal (256), the sensed lamp current signal (264), and the sensed lamp power signal (258), and the HID lamp control signal is the total error signal (242).
- 9. The ignition and operation control circuit of claim 8 further comprising a dimming circuit (226), the dimming circuit (226) generating a dimming signal (278), wherein the ballast microcontroller (200) is responsive to the dimming signal (278).
- 10. The ignition and operation control circuit of claim 8 further comprising a calibration circuit (228), the calibration circuit (228) generating a calibration signal (280), wherein the ballast microcontroller (200) is responsive to the calibration signal (280).
- 11. A method of ignition and operation control for an electronic ballast for an HID lamp (216) comprising:
providing a ballast microcontroller (200), the ballast microcontroller (200) being responsive to at least one high intensity discharge (HID) lamp feedback signal and generating an HID lamp control signal; providing a parallel capacitive circuit (214), the parallel capacitive circuit (214) operably connected parallel to the HID lamp (216); providing an inductive circuit (212), the inductive circuit (212) being operably connected to the parallel capacitive circuit (214); switching power (252) to the inductive circuit (212) in response to the HID lamp control signal; and monitoring the HID lamp (216) to generate the at least one high intensity discharge (HID) lamp feedback signal.
- 12. The method of claim 11 further comprising storing a look-up table in the ballast microcontroller (200), the look-up table providing the HID lamp control signal for a given HID lamp feedback signal.
- 13. The method of claim 11 further comprising:
storing constants in the ballast microcontroller (200), and calculating the HID lamp control signal for a given HID lamp feedback signal using the constants.
- 14. The method of claim 13 wherein storing constants in the ballast microcontroller (200) comprises storing constants in the ballast microcontroller (200) in response to a calibration signal (280).
- 15. The method of claim 11 wherein monitoring the HID lamp (216) to generate the at least one high intensity discharge (HID) lamp feedback signal comprises monitoring the HID lamp (216) to generate an ignition voltage signal (266).
- 16. The method of claim 15 further comprising:
monitoring the inductive circuit (212) to generate a sensed inductor current (270); and applying a DC offset voltage across the HID lamp (216) in response to the sensed inductor current (270).
- 17. The method of claim 15 further comprising:
monitoring the inductive circuit (212) to generate a sensed inductor current (270); and clamping current flow through the inductive circuit (212) if the sensed inductor current (270) exceeds a predetermined value.
- 18. The method of claim 17 wherein clamping current flow through the inductive circuit (212) if the sensed inductor current (270) exceeds a predetermined value further comprises clamping current flow through the inductive circuit (212) to limit the voltage to the HID lamp (216) to a sensed rail voltage output voltage (276).
- 19. The method of claim 11 wherein monitoring the HID lamp (216) to generate the at least one high intensity discharge (HID) lamp feedback signal comprises monitoring the HID lamp (216) to generate a sensed lamp current signal (264).
- 20. The method of claim 11 wherein monitoring the HID lamp (216) to generate the at least one high intensity discharge (HID) lamp feedback signal comprises monitoring the HID lamp (216) to generate a sensed rail voltage signal (256), a sensed lamp current signal (264), and a sensed lamp power signal (258).
- 21. The method of claim 11 further comprising dimming the HID lamp (216) in response to a dimming signal (278) to the ballast microcontroller (200).
- 22. A system of ignition and operation control for an electronic ballast for an HID lamp (216) comprising:
a ballast microcontroller (200), the ballast microcontroller (200) being responsive to at least one high intensity discharge (HID) lamp feedback signal and generating an HID lamp control signal; a parallel capacitive circuit (214), the parallel capacitive circuit (214) operably connected parallel to the HID lamp (216); an inductive circuit (212), the inductive circuit (212) being operably connected to the parallel capacitive circuit (214); means for switching power (252) to the inductive circuit (212) in response to the HID lamp control signal; and means for monitoring the HID lamp (216) to generate the at least one high intensity discharge (HID) lamp feedback signal.
- 23. The system of claim 22 further comprising means for storing a look-up table in the ballast microcontroller (200), the look-up table providing the HID lamp control signal for a given HID lamp feedback signal.
- 24. The system of claim 22 further comprising:
means for storing constants in the ballast microcontroller (200), and means for calculating the HID lamp control signal for a given HID lamp feedback signal using the constants.
- 25. The system of claim 24 wherein means for storing constants in the ballast microcontroller (200) comprises means for storing constants in the ballast microcontroller (200) in response to a calibration signal (280).
- 26. The system of claim 22 wherein means for monitoring the HID lamp (216) to generate the at least one high intensity discharge (HID) lamp feedback signal comprises the means for monitoring the HID lamp (216) to generate an ignition voltage signal (266).
- 27. The system of claim 26 further comprising:
means for monitoring the inductive circuit (212) to generate a sensed inductor current (270); and means for applying a DC offset voltage across the HID lamp (216) in response to the sensed inductor current (270).
- 28. The system of claim 26 further comprising:
means for monitoring the inductive circuit (212) to generate a sensed inductor current (270); and means for clamping current flow through the inductive circuit (212) if the sensed inductor current (270) exceeds a predetermined value.
- 29. The system of claim 28 wherein means for clamping current flow through the inductive circuit (212) if the sensed inductor current (270) exceeds a predetermined value further comprises means for clamping current flow through the inductive circuit (212) to limit the voltage to the HID lamp (216) to a sensed rail voltage output voltage (276).
- 30. The system of claim 22 wherein means for monitoring the HID lamp (216) to generate the at least one high intensity discharge (HID) lamp feedback signal comprises means for monitoring the HID lamp (216) to generate a sensed lamp current signal (264).
- 31. The system of claim 22 wherein means for monitoring the HID lamp (216) to generate the at least one high intensity discharge (HID) lamp feedback signal comprises means for monitoring the HID lamp (216) to generate a sensed rail voltage signal (256), a sensed lamp current signal (264), and a sensed lamp power signal (258).
- 32. The system of claim 22 further comprising means for dimming the HID lamp (216) in response to a dimming signal (278) to the ballast microcontroller (200).
Parent Case Info
[0001] This application claims priority from and incorporates herein by reference U.S. Provisional Application No. 60/342,951, entitled High Frequency Ballast, filed Dec. 21, 2001.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/US02/10919 |
4/5/2002 |
WO |
|
Provisional Applications (1)
|
Number |
Date |
Country |
|
60342951 |
Dec 2001 |
US |