| 主权项 |
1. A control circuit for a step-up DC/DC converter, wherein the step-up DC/DC converter comprises an inductor, a rectifier diode, an output capacitor, and a switching transistor,
and wherein the switching transistor is configured such that its on resistance is switchable between at least two values, and wherein the control circuit is configured such that, when the switching transistor is switched from off to on, the control circuit sets the on resistance of the switching transistor to a first value for a first period immediately after the switching of the switching transistor, following which the control circuit sets the on resistance of the switching transistor to a second value that is smaller than the first value for a second period until the switching transistor is turned off, wherein, with a series resistance component of a loop comprising the output capacitor, the rectifier diode, the switching transistor, and a ground line as R, with a capacitance component of this loop as C, and with a series inductance component of this loop as L, the first value is determined such that the relation R/(2√(L/C))>1 is satisfied. |
