| 摘要 |
<p>The present application discloses an apparatus (100) for providing a power output proportional to a source signal. The apparatus (100) comprises a phase modulator (106) driving an upper and lower power driver (108,110) with substantially the same carrier waveforms having a relative phase difference there between. The carrier waveforms may have a signal modulated thereon. The power drivers (108,110) are each coupled to a resonator circuit (112,116) such that they operate as a substantially zero-voltage zero-current switching element. The output of the two power drivers (108,110) is fed into a respective upper and lower transformers (114,118) that are substantially electromagnetically identical to one another and providing electrical isolation. On the secondary side of each of the upper and lower transformer (114,118) are identical symmetrical secondary circuits that have a rectifier stage electrically connected to an inductor (L5) in series with an upper capacitor (C1) to form an upper low pass filter having a corner frequency greater than the source frequency and less than the carrier frequencies, and further serving to integrate the source signal, a semiconductor switch (M1) electrically connected to an electrical junction between the inductor and rectifier stage to provide a return path for high-frequency current to ground, and an output element electrically connected to an electrical junction between the inductor and capacitor. The inductor (L10) associated with the lower secondary circuit is highly coupled (>=0.99) to the upper inductor (L5), such that the high speed semiconductor switches (M1,M2) operate as substantially zero-voltage zero-current switching elements. An output is formed across the upper and lower output elements that is isolated from rail voltage and more preferably balanced with bi-directional current.</p> |
