摘要 |
A switched-mode self-oscillating supply voltage circuit for converting an input voltage into an output d.c. voltage which is substantially independent of variations of the input voltage and/or a load connected to the output voltage. The circuit comprises a first controllable switch connected in series with a transformer winding and a second controllable switch for turning-off the first switch. The conduction period of the first switch is controlled by means of a control voltage present on a control electrode of the second switch. The circuit can be switched-over to a stand-up state in which the energy supplied to the load is reduced to zero. A starting network is connected between the input voltage and the second switch so that the current therein flows through the second switch during the period of time this switch conducts and does not flow to the control electode of the first switch in the stand-by state.
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