Abstract: The specification may disclose a switching power supply operated in a discontinuous current power factor corrected mode, having multiple boost circuits or boost modules, and controlled by a digital signal processor. The digital signal processor may implement a control scheme whereby the duty cycle of the switching signals applied to the boost modules may be controlled, in part, by the amount of power delivered to the load in the previous half cycle of the source voltage. In another aspect, an output voltage correction to the switching signals may be applied at the end of each half cycle, which may result in voltage correction at twice the source frequency.

Abstract: The specification may disclose a switching power supply operated in a discontinuous current power factor corrected mode, having multiple boost circuits or boost modules, and controlled by a digital signal processor. The digital signal processor may implement a control scheme whereby the duty cycle of the switching signals applied to the boost modules may be controlled, in part, by the amount of power delivered to the load in the previous half cycle of the source voltage. In another aspect, an output voltage correction to the switching signals may be applied at the end of each half cycle, which may result in voltage correction at twice the source frequency.

Abstract: A snubber circuit with two switches which are switched together. The two switches form a pair of active networks with complementary diode locations, and a capacitor is connected to provide a path for transient current through both diodes. The two switches are preferably switched simultaneously to minimize conduction losses. When Switches S1 and S2 are turned off, the voltage through across capacitor Cs is nearly zero. Turning off S1 and S2 causes current flowing through S1 and S2 to be diverted through D1, Cs, and D2. Therefore, the voltage across S1 and S2 is a very low value and consequently, the turn-off losses are low. Alternatively, at the time when S1 and S2 are turned on, the peak current through S1 and S2 is equal to the boost inductor current. Therefore switching losses are minimized and the converter can operate at higher frequencies.

Abstract: A soft-switching DC to DC power converter which minimizes switching losses from a no load condition to a full load condition while operating at fixed frequency. Output voltage control is achieved by controlling the phase angle between the two switching networks. High frequency transformer primaries are always excited with a square wave input voltage equal to ##EQU1## The power converter can be implemented with a single transformer. Moreover, the switch voltage never increases the input DC voltage from no load to full load. The power converter can be used in both low voltage high current applications and high voltage low current applications.