SLUA159 Datasheet, PDF (12/28 Pages) Texas Instruments – Zero Voltage Switching Resonant Power Conversion

APPLICATION NOTE
Expanding ZVS to Other Topologies
ZVS Forward Converter - Single Ended:
The single ended forward converter can easily
be configured for zero voltage switching with
the addition of a resonant capacitor across the
switch. Like the buck regulator, there is a high
voltage excursion in the off state due to reso-
nance, the amplitude of which varies with line
and load. The transformer can be designed so
that its magnetizing and leakage inductance
equals the required resonant inductance. This
simplifies transformer reset and eliminates one
component. A general circuit diagram is shown
in Fig. 12 below. The associated waveforms for
when &RI ^eq ^{uals LR are shown in Fig. 13.}
0
Fig. 12 -- ZVS Forward Converter
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