| 摘要 |
PURPOSE:To regulate output current economically, by setting a sub-switching- element turning a one-side switching element OFF forcibly with the delay of a specified time from the starting time point of the ON-period of the one-side switching element, and by driving the sub-switching element with feedback winding output. CONSTITUTION:An inverter is composed by connecting the transistors(hereinafter, Tr)Q1-Q2 of main switching elements to both the ends of a DC power source E in series, and by connecting respective diodes D1-D2 to the Tr Q1-Q2 in antiparallel with each other; and to both the ends of the Tr Q1, a load circuit RL is connected via a coupling capacitor C0 and a current transformer T1. The inverter is provided with a starting circuit ST, and to a space between the base and emitter of the Tr Q2, the Tr Q3 of a sub-switching element is connected, and to the base, a diode D3 and a dimming switch SW1 are connected. Besides, the transformer T1 is provided with a tertiary winding n4, and to the winding, the switch SW1 is connected via an impedance Z. Then, a lamp l can be switched to a dimming and full lit state. |
