JPH0118386B

PCT No. PCT/JP80/00151 Sec. 371 Date Mar. 2, 1981 Sec. 102(e) Date Feb. 20, 1981 PCT Filed Jun. 30, 1980 PCT Pub. No. WO81/00159 PCT Pub. Date Jan. 22, 1981.An output voltage-drop detecting apparatus added to a stabilized DC power source device which includes a power control circuit for controlling a DC input voltage to produce a DC output voltage of a specified value, a reference voltage source whose voltage is capable of being varied, and an error amplifier, with the DC output voltage and the reference voltage being compared by the error amplifier and the power control circuit being controlled by the output of the error amplifier to stabilize the output voltage. The output voltage-drop detecting apparatus divides the reference voltage obtained from the reference voltage source which is provided in the stabilized DC power source device, thereby to produce a reference voltage for the output voltage-drop detecting apparatus, and compares this reference voltage and the output voltage by means of a comparator, the arrangement being such that the comparator delivers a detection signal when the output voltage of the stabilized DC power source device drops below the reference voltage for the output voltage-drop detecting apparatus.