Switching power supply circuit control method

A switching power supply circuit control method for controlling a switching power supply circuit, wherein

• said switching power supply circuit includes:
• first and second input terminals;
• first and second output terminals to which a capacitor and a load are connected;
• a second power supply line connecting said second input terminal and said second output terminal;
• and
• one or more circuits,
• each of said one or more circuits includes:
• a first power supply line connecting said first input terminal and said first output terminal;
• a reactor provided on said first power supply line;
• a diode connected in series to said reactor on said first power supply line, and positioned such that an anode thereof is directed toward said reactor;
• and
• a switch element provided between said second power supply line and a point between said reactor and said diode,
• said switching power supply circuit control method comprising steps of:
• making said switch element of each of said one or more circuits nonconductive when power consumption of said load is smaller than a first threshold to supply power from all of said one or more circuits to said load, and
• making said switch element of at least one of said one or more circuits intermittently conductive when said power consumption of said load is larger than said first threshold to supply power from all of said one or more circuits to said load.