The present invention has an object to provide a switching regulator power supply apparatus that realizes a plurality of light emitting amount outputs without increasing a total number of structural components thereof. A switching regulator power supply apparatus according to the present invention includes a switching type power converting circuit; a current detecting circuit for producing a feedback signal in response to a load current; and an SWR control circuit for driving the power converting circuit. In the switching regulator power supply apparatus, the SWR control circuit is provided with a control signal input terminal and a reference voltage circuit capable of outputting a plurality of reference voltages based upon a control signal inputted to the control signal input terminal.