| 摘要 |
A dual-output DC-DC converter comprises a field-effect transistor (30) connected to a one terminal of a DC voltage source (2), the transistor having an inherent parasitic diode (30a) in parallel relationship therewith. A resonant circuit (5) is coupled at one end to the other terminal of the voltage source and a first diode (31) is connected between the transistor and the other end of the resonant circuit to allow a forward current to flow therein. A second diode (32) is connected in parallel with a series circuit formed by the transistor and the first diode to allow current to flow in the reverse direction, the second diode having a recovery time much smaller than the recovery time of the parasitic diode. A first rectifier-filter (9) is coupled to the resonant circuit for developing a first DC output voltage, and a second rectifier-filter (10) is coupled across the terminals of the DC voltage source through the transistor for developing a second DC output voltage. A third diode (33) is connected between the DC voltage source and the second rectifier-filter for blocking current which would otherwise flow through the first and second diodes and the second rectifier-filter. Deviations of the first and second DC output voltages respectively from a reference voltage are detected (34) and the gate of the transistor is driven (35) by switching pulses having a frequency variable as a function of the deviation of the first DC output voltage and having a duration variable as a function of the deviation of the second DC output voltage. <IMAGE>
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