| 摘要 |
PROBLEM TO BE SOLVED: To provide a fluorescent lamp high frequency constant current lighting circuit in which fluorescent lamp lighting conditions are satisfied in a connected state of a fluorescent lamp load, in which accidents of abnormal high voltage or overheating of a current transformer will not occur in the case where a load circuit is opened, and in which load fluorescent lamps can be separately and securely restarted without restarting a power source circuit after they are replaced. SOLUTION: Using a current transformer 3 provided with a gap comprising a primary winding and a secondary winding 4 wound around a circular core having a micro-gap 30, a high frequency constant current is supplied to the primary winding, a first and a second taps 4b, 4c are provided on the secondary winding 4, one terminal of each of two filaments of a fluorescent lamp 5 is connected to each terminal of the secondary winding 4, the other terminal of each is connected to the first and the second tap 4b, 4c of the secondary winding 4 through a PTC thermister T1, T2, and a capacitor 6 is connected between the other terminals of the two filaments. |
