| 摘要 |
<p>Provided is a lighting circuit (10) which includes a line voltage source (12) used to supply a full wave signal to circuit (10). A ballast (14) is connected to the line voltage source (12), and a lamp (16). Further included in the circuit (10) is an electronic starter (18) which is connected across the lamp (16). Electronic starter (18) includes a pulse generating circuit (60, 62, 64), a switch (30 which is connected to provide a cathode current pulse 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 which is delivered to cathodes (22) and (26). A feedback or pulse timeout circuit may also be used to sense a current delivered to cathodes by cathode current pulse. Upon sensing a current value at least equal to a predetermined value, the feedback circuit acts to disable electronic starter. Inclusion of the feedback circuit provides for precise control of energy being delivered to lamp (16). A shutdown circuit (52, 54, 56, 58) may be used to disable the electronic starter (18) after a predetermined event. <IMAGE></p> |
