Switching power supply employing an internal resistance in series with a zener diode to stabilize a DC output

摘要

A switching power supply includes a rectifying and smoothing circuit 6 coupled to an inductor L1 and a zener diode D2 coupled to the output of the rectifying and smoothing circuit 6. An internal resistor on the inductor L1 side viewed through the rectifying and smoothing circuit 6 is employed as a serial resistor for generating the voltage drop which is required for the zener diode D2 to absorb voltage fluctuation, whereby the voltage of the DC output 22 is stabilized.