| 摘要 |
<P>PROBLEM TO BE SOLVED: To constitute a switching control circuit that is suppressed in increase of the number of terminals by reducing restriction on a selectable function and making an existing terminal share a function (making the terminal possess a concealed function), and a compact and low cost switching power supply device. <P>SOLUTION: A return signal is input to a feedback terminal FB of an IC 202 for switching control from a return circuit 12. A capacitor C4 and a Zener diode D4 are connected between the feedback terminal FB and a ground terminal. The Zener diode D4 is an external circuit which is selectively connected, and voltage of the feedback terminal FB at overcurrent operation varies depending on presence or absence of the external circuit. A return/latch determination circuit 26 detects the voltage of the feedback terminal FB, and switches an automatic return system and a latch system in an overcurrent operation state. <P>COPYRIGHT: (C)2012,JPO&INPIT |
