| 摘要 |
The switching regulator of a synchronous rectifying mode comprises the first and second switches SW1, SW2 arranged in series between the power source Vdd and the ground Vss, the switch control unit 1 which controls the on-off operation of the switches SW1, SW2, and the smoothing circuit 4 which smoothes the output node potential Vnd. When the signal Sc1 indicates that the output node potential Vnd goes below the first reference potential Vr1 which is the reference to detect the occurrence of the inrush current while the first switch SW1 is in the ON state, the control circuit 10 turns off the first switch SW1. Thus, the detection of the inrush current is conducted by making use of a voltage drop due to the on resistance of the first switch SW1, so that it is unnecessary to provide a resistance element for detecting the inrush current. <IMAGE> |
