| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a switching power supply circuit in which a switching element and an inductive load can be protected against deterioration and breakdown, by preventing generation of a power supply in-rush current, when control of power supply starting process is switched in a self-bias switching power supply. <P>SOLUTION: At the switching point from non-controlled oscillation start operation to controlled oscillation starting operation, output potential of an error amplifier 15 which is not controlled during non-controlled oscillation start operation is fed back, based on the potential difference between the power supply input voltage V<SB>IN</SB>and the power supply output voltage V<SB>OUT</SB>, such that the "main oscillation" can be started from a potential for surely generating a pulse width that is required by main and rectifying switches. <P>COPYRIGHT: (C)2007,JPO&INPIT |
