| 摘要 |
Provided is a lighting circuit (10, 100, 160) which includes a line voltage source 12 used to supply a full wave signal 72 to circuit 10. A ballast 14 is connected to the line voltage source 12, and a lamp 16. Further included in the circuit (10, 100, 160) is an electronic starter (18, 102, 159) which is connected across the lamp 16. Electronic starter (18, 102, 159) includes a pulse generating circuit ((60, 62, 64) (108, 110, 112, 152, 154)), a switch (30, 120) which is connected to provide a cathode current pulse 74 to first and second cathodes (22, 26) of the lamp 16, generated by the pulse generating circuit. The pulse generating circuit and switch operate in such a manner that the pulse generating circuit limits the duration of the cathode current pulse 74 which is delivered to cathodes 22 and 26. A feedback or pulse timeout circuit (116, 118, 120, 121, 128, 130) may also be used to sense a current delivered to cathodes 122, 126 by cathode current pulse 74. Upon sensing a current value at least equal to a predetermined value, the feedback circuit acts to disable electronic starter (102, 159). Inclusion of the feedback circuit provides for precise control of energy being delivered to lamp 16. A shutdown circuit (52, 54, 56, 58) (114, 122, 124, 146) may be used to disable the electronic starter (18, 102) after a predetermined event.
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