| 摘要 |
PURPOSE:To avoid the effect on a circuit connected to an output stage due to momentary voltage fluctuation, by connecting the other output stage in parallel with a switching element driving an output stage of a switching power supply constituting a closed loop. CONSTITUTION:A base of an output transistor (TR)Q3 connected to a power supply terminal A is connected to a collector of a drive TRQ2 via a resistor r4. An output obtained at the collector is smoothed at a filter 11 comprising a diode D2, an inductor L2 and a capacitor C2 and outputted at an output power supply terminal C. When a load for the terminals B and C is the same and the filter 11 is constituted the same as a filter 8, although the terminal C is not constituted as a closed loop like the terminal B, an output voltage Vc at the terminal C is Vc=VB against the fluctuation of an input power supply, and even if the voltage is momentarily fluctuated, the effect on the circuit connected to the terminal B of stabilized output power supply can be avoided. |
