| 摘要 |
<p>Provided is a DC-DC converter (20,L1,C1) comprising: a drive switching element (SW1) so that a current flows to an inductor (L1), the drive switching element (SW1) being driven by a PWM control pulse (S1) or a PFM control pulse (S1), wherein a direct-current input voltage (Vin) supplied from a direct-current power source is converted so as to output the converted direct-current voltage (Vout) having a different potential, and wherein a PWM control is performed when a load is larger than a predetermined value and a PFM control is performed when the load is smaller than the predetermined value, the DC-DC converter further comprising: a pulse width regulation section (21,22,24,29) to regulate the PWM control pulse so as not to have a pulse width smaller than a predetermined pulse width, at least when the PFM control is switched to the PWM control.</p> |
