摘要 |
The converter delivers current to an intermittently energized load and includes a coupled inductor having a primary winding, a secondary winding and a feedback winding. A switching translator is coupled in series with the primary winding of the inductor and switches between conductive and non-conductive states to control the flow of current through the primary winding. A positive drive circuit provides positive bias voltage to the switching transistor. A current limiting circuit senses the base voltage of the switching transistor to measure the primary winding current, removes the positive bias voltage when the primary winding current reaches a predetermined value, and thereby switches the transistor out of the conductive state into the non-conductive state. A negative drive circuit is coupled between the feedback winding and the base of the switching transistor and supplies a constant negative bias voltage to the transistor base as energy is transferred from the inductor into a load. The negative bias voltage remains constant as the voltage across the feedback varies.
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