Abstract: An inventive oscillator, inter alia, is disclosed which can be used to generate a frequency modulated control signal or a pulsewidth modulated control signal for application to a switching means in a switching power supply. The output voltage of a power supply is used to control the magnitude of a high bias voltage and a low bias voltage applied to a plus terminal of a voltage comparator, wherein when the output of the voltage comparator is high, the high bias voltage is applied to the plus terminal, and when the output of the voltage comparator is low, the low bias voltage is applied to the plus terminal. A capacitor, coupled to the output of the voltage comparator via a resistor, is coupled between the minus terminal of the voltage comparator and a ground so that when the output of the voltage comparator is high the capacitor charges.

Abstract: A control circuit is disclosed which provides a pulsewidth modulated, quasi-squarewave control signal to a switching transistor in a non-symmetrical switching power supply. A primary winding of a sense transformer is coupled in series with a switching transistor and a first winding of a magnetic device, such as a power transformer. A load resistor is placed across a secondary winding of the sense transformer so that the voltage across the secondary winding of the sense transformer ramps up with the current through the first winding of the magnetic device. This increasing voltage is compared by a voltage comparator to a feedback signal corresponding to the output voltage of the power supply so that when the voltage across the secondary winding of the sense transformer exceeds that of the feedback signal, the output of the voltage comparator will be low, turning the switching transistor off. The magnetic device now dumps its stored energy into the output load.

Abstract: An inventive voltage regulator is herein described to provide voltage regulation while maintaining electrical isolation between the input and output sections of a power supply. In a switching regulator for a power supply, a core of the sense transformer is charged until the sense transformer becomes saturated. The charging power is then removed from, for example, the primary winding, and the voltages across the primary and secondary windings reverse polarity and begin to rise. The voltage across the primary winding rises until it forward biases a low power diode connected between a non-grounded output terminal of the power supply, at an output voltage of V.sub.out, and the primary winding of the sense transformer. Thus, the voltage across the primary winding is clamped to the output voltage plus a diode voltage drop. As the energy in the sense transformer dissipates into an output load connected to the output terminals of the power supply, a voltage corresponding to V.sub.