Patent ID: 8120339

Claim:
A switching power supply, comprising: a first switching unit which receives an input voltage from an external power source and performs a first switching operation to intermittently receive a first electric current from the external power source and to produce a first voltage, different from the input voltage, from the input voltage and the first electric current; a second switching unit which receives the input voltage from the external power source and performs a second switching operation to intermittently receive a second electric current from the external power source and to produce a second voltage, different from the input voltage, from the input voltage and the second electric current; and an output terminal which receives the first voltage of the first switching unit and the second voltage of the second switching unit and through which an output voltage obtained by combining the first and second voltages is outputted, wherein a maximum value of the first electric current is higher than a maximum value of the second electric current; wherein the first switching unit has a first resistive element which sets the first electric current received in the first switching unit, and the second switching unit has a second resistive element which sets the second electric current received in the second switching unit; and wherein the first resistive element is a first resistor through which the first electric current flows, the second resistive element is a second resistor through which the second electric current flows, and a resistance of the second resistor is larger than a resistance of the first resistor to set the maximum value of the second electric current lower than the maximum value of the first electric current.