DUAL REGULATED POWER SUPPLY

A dual regulated DC power supply produces an output voltage which is the sum of a variable DC control voltage and a floating DC voltage. The control voltage, generated by a first differential amplifier having an inverted input coupled to the power supply output through a feedback scaling circuit, varies in inverse relation to the change in power supply output voltage. The floating DC voltage is produced by isolating, rectifying and filtering the output of an oscillator having a peak voltage controlled by an applied bias voltage. The applied bias voltage is generated by a second differential amplifier coupled to compare the control voltage with a selected reference voltage so that a change in control voltage causes a change in the floating voltage. The control voltage changes rapidly in compensating response to transient changes in power supply voltage while the floating voltage changes more slowly in compensating response to output voltage changes due to sustained load swings.