Patent ID: 7777462
Filing Date: 2010-08-17
Classification: H02M,Y10S

Abstract:
1. A power supply unit, comprising: a plurality of semiconductor devices; a plurality of inductors coupled to the semiconductor devices, respectively; and an output capacitor commonly coupled to the inductors, each of the semiconductor devices including: a power supply input terminal to which an external power supply voltage is input; a ground voltage terminal to which a ground power supply voltage is input; a switch terminal coupled to an inductor corresponding to itself among the inductors; a first input terminal to which a first pulse input signal is input; a first circuit that receives the first pulse input signal, and generates a first pulse output signal after a first delay time has elapsed; a first output terminal that outputs the first pulse output signal; a transistor that couples the switch terminal to the power supply input terminal or the ground voltage terminal; and a control circuit that controls on/off of the transistor using the first pulse input signal as a starting point, wherein the semiconductor devices are mutually coupled in a ring shape with the first output terminal of itself being coupled to the first input terminal of any one of the semiconductor devices other than itself.