Appeal No. 2000-2255
Application No. 09/123,522
changes the AC voltage from an input waveform having any duty
cycle into an output sinusoidal waveform with a 50% duty cycle in
which a time ratio of positive and negative half cycles are
identical. A current doubler type rectification-smoothing
circuit receives the output sinusoidal waveform from the
piezoelectric transformer and produces an output having zero-
ripple current.
Claim 1 is illustrative of the invention and reads as
follows:
1. A DC/DC converter comprising:
a switch for converting a DC voltage into an AC
voltage;
a piezoelectric transformer for changing said AC
voltage from an input waveform with any duty into an
output sinusoidal waveform with a 50% duty in which a
time ratio of positive and negative half cycles are
identical; and
a current doubler (Double Ended Converter using
Two Inductors) type rectification-smoothing circuit
that receives the output sinusoidal waveform from the
piezoelectric transformer and outputs zero-ripple
current.
The Examiner relies on the following prior art:
Newton et al. (Newton) 5,663,876 Sep. 02, 1997
(filed Sep. 25, 1995)
Zaitsu 5,739,622 Apr. 14, 1998
(filed Aug. 05, 1996)
2
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