Dc/dc converter, switching power supply device, and electronic apparatus,configured to include a phase detector and a phase holder

Abstract

Provided is a DC/DC converter for a multi-phase switching power supply device which include a plurality of DC/DC converters including a master DC/DC converter and a plurality of slave DC/DC converters that are connected in parallel to each other and operate in different phases. The DC/DC converter includes: first and second terminals to cascade the plurality of DC/DC converters in a line; a phase detector that detects the number of operating converters in the switching power supply device and the phases of the plurality of DC/DC converters, on the basis of a current input to the first terminal and a current output from the second terminal; a phase holder that holds the detected phases and outputs a phase holding signal; and a clock generator that selects a clock corresponding to the phase of a host converter from multi-phase clocks, on the basis of the phase holding signal, and outputs the selected clock. The DC/DC converter performs a switching operation on the basis of the selected clock.