Abstract: A DC-to-DC converter, comprising: inverter means for receiving a DC input and providing as an output a high-frequency, alternately pulsed current waveform; a control winding for receiving the output of the inverter means, the control winding being wound on a common bobbin with first and second tank windings, the windings de-coupled on the bobbin so that there is a significant leakage inductance between the windings, the first and second tank windings having two discrete resonant frequencies on a common core and flux path, a main primary winding wound in series with the control winding, the main primary winding being wound onto a separate bobbin and residing on its own core leg and flux path, first and second secondary windings coupled with the main primary winding, the first and second secondary windings being wound out of phase with each other, the first and second secondary windings feeding, respectively, first and second diodes, the first and second diodes rectifying the alternately pulse current waveform

Abstract: A new circuit for the operation of gas discharge lamps via a converter that operates directly off the rectified AC line without reactive filtering and consequently maintains good power factor and low total harmonic distortion while still maintaining an acceptable lamp current crest factor. The converter employs active crest factor correction to control the actual lamp current to a determined peak to RMS value. The design comprises two stages: a first stage with a non-linear input voltage to lamp current transfer function and a second stage having a frequency modulation to lamp current transfer function designed to cancel the first stage's transfer function at a predetermined input voltage and thus maintain constant lamp current during the correction interval.

Abstract: The present invention provides a resonant power converter for changing the magnitude of a DC voltage. The converter includes a common magnetic core with three legs (an "EE" core). The core has primary and secondary windings wound onto a first outside leg, and a tank winding and control windings wound onto a second outside leg. Control switch means are provided for effecting alternate pulses of current flow through the primary winding to effectuate alternate flux flow, the control switch means and the primary winding having a predetermined parasitic capacitance with a predetermined delay time between the termination of a given pulse and initiation of the succeeding pulse. The secondary windings are oriented to conduct alternately in phase with the alternate flux flow, there being inherent in the first leg of the transformer a magnetizing inductance, such that the magnetizing current will be great enough to charge said parasitic capacitance in a controlled fashion.

Abstract: A zero current/zero voltage resonant DC to DC converter operating at high frequency, utilizes the series/parallel approach to power conversion. A resonant transformer assembly is inserted into either the primary or secondary of the main transformer, to optimize the operating parameters of the converter.

Abstract: A resonant power converter is disclosed which is constructed on an integrated magnetic core, with primary, secondary and tertiary windings occupying separate legs of the core. The tertiary winding is connected in a resonant circuit and induces a flux in the primary leg that causes the primary winding current to assume the shape of a series of generally sinusoidal pulses. Primary winding switching can thus occur at zero primary current between pulses, thereby eliminating prior interference problems. Furthermore, the converter can be operated in a pulse width modulated mode to accommodate for varying output load levels without the problems of low frequency operation encountered by prior frequency modulated resonant converters.