| 摘要 |
<p>A converter for the conversion of an input voltage (Ui) between a first (1) and a second supply terminal (2) into an output voltage (U0), comprising switching means (S) which in operation are turned on and turned off alternately under control of a control signal (Vcntrl), an inductive element (T) serially connected with the switching means (S), a control circuit (CNTRL) for supplying the control signal (Vcntrl), and evaluation means (EVMNS) for evaluating a ringing voltage (US) across the switching means (S). The frequency of the control signal (Vcntrl) is approximately constant and is determined by an oscillator (OSC). The control circuit turns on the switching means (S) only when at the same time: the voltage (US) is smaller than the input voltage (Ui), and the derivative with respect to time of the voltage (US) is smaller than or equal to zero, and equals a reference value (RF).</p> |
