| 摘要 |
PURPOSE:To reduce switching loss by supplying start pulses properly only when it is found necessary to supply them to switching transistors. CONSTITUTION:A diode D1 to constitute a discharging circuit in an inverter circuit is provided. In order further to constitute a bias circuit, a resistance R2, a diode D2, a capacitor C6 and a resistance R3, a diode D3 and a capacitor C7 are connected between each transistor(Tr) Q1 to Q2 and windings M2 to M3. In putting the power supply AC to work, start pulses are applied to the base of the Tr Q2 from a starter circuit by a time constant circuit, etc., by which the inverter circuit starts operation and turns on a fluorescent lamp FL. In addition, when the operation is started, with the Tr Q2 ON the energized electric charge of a capacitor C5 in the starter circuit is discharged through the diode D1 and Tr Q2. During the operation of the inverter circuit no start pulses will be applied to the Tr Q2 as a result. |
