| 摘要 |
PURPOSE:To improve the load regulation by connecting a resistor in series with a feedback winding and obtaining a CD voltage through the resistor. CONSTITUTION:A switching control type power source has an input rectifier 1, a blocking oscillator 2, a converter transformer 3, an error detector 4, a controller 5, and an output rectifier 6, a positive feedback current If is supplied from a feedback winding NB through a base current limiter SK to the base of a transistor TR4 to perform a blocking oscillation in the oscillator 2, and controlled in response to the output of the detector 4. In this case, a resistor R16 is inserted in series between (e) terminal of the winding NB and a diode D6. Thus, if the output current of the output winding N2 increases, the induced voltage to the winding NB increases, but the rise of the detected voltage stored in the capacitor C3 is suppressed by rectifying via the diode D6 due to the voltage drop of the resistor R16, and the ON period of the switching transistor Tr4 is increased. |
