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

A DC/DC converter for a multi-phase switching power supply device which includes 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 comprising:

• first and second terminals that cascade the plurality of DC/DC converters in a line;
• a phase detector that detects the number of operating converters amongst the converters connected in parallel and the phases of the DC/DC converters, on the basis of a current which flows to the first terminal and a current which flows from the second terminal;
• a phase holder that holds the detected phases and outputs a phase holding signal indicating the detected phases;
• and
• a clock generator that selects a clock corresponding to the phase of a host converter from multi-phase clocks which are generated from a reference clock, on the basis of the phase holding signal, and outputs the selected clock to the DC/DC converter,
• wherein the DC/DC converter performs a switching operation on the basis of the selected clock output from the clock generator.