| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a DC-DC converter capable of lengthening the period in which the boosting of an output voltage is continued as compared with a conventional DC-DC converter. <P>SOLUTION: A distortion circuit 24 prevents a variable DC voltage Vber from exceeding the peak value of a sawtooth wave by controlling the variable DC voltage Vber to 0.8 V. As a result, in the distortion circuit 24, the maximum value of the duty ratio of a pulse signal inputted into a gate terminal G of a field-effect transistor Tr is prevented from becoming 1 (100%) to extend a period until the field-effect transistor Tr is continuously kept in a conductive state. By this arrangement, the boosting of the output voltage by a step-up circuit 21 can continue without stopping. Accordingly, a DC-DC converter 20 extends the period in which the boosting of the output voltage continues as compared with the conventional DC-DC converter. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
