In a case of using the low-side current detection circuit 170_1 for providing zero-crossing detection, the switches SW51 and SW52 are turned off. In a case of using the low-side current detection circuit 170_1 for providing the NCP function, one from among the switches SW51 and SW52 is turned on so as to provide an offset, thereby allowing a negative threshold value to be set. By switching the on/off states of the switches SW51 and SW52, this arrangement allows the threshold value to be scaled.

Next, description will be made regarding a desired layout of the power management circuit 100. In the second mode, the two circuit blocks BLK1 and BLK2 are coupled to a common inductor. The circuit blocks BLK1 and BLK2 are required to operate at substantially the same timing.

FIG. 9 is an exemplary layout diagram showing the power management circuit 100. The two circuit blocks BLK1 and BLK2 are laid out such that they are mirror images of each other. This allows the impedance between the circuit block BLK1 and the inductor L1 and the impedance between the circuit block BLK2 and the inductor L1 to match each other.