ELECTRIC POWER SUPPLY SYSTEM AND SWITCHING ELECTRIC POWER SOURCE APPARATUS

Provided is an electric power supply system comprising: an energy harvesting electric power source; and a switching electric power source apparatus which boosts an input voltage supplied from the energy harvesting electric power source for an output, where the switching electric power source apparatus has: an input terminal; an output terminal; a coil; a first switch; a diode; a capacitor; a voltage conversion unit which outputs a converted voltage that is based on the input voltage; and a switch control circuit which outputs a signal having a frequency corresponding to the converted voltage and driving the first switch, where the voltage conversion unit converts the input voltage such that an output impedance of the energy harvesting electric power source and an input impedance of the switching electric power source apparatus have closer values than in a case where the input voltage is inputted to the switch control circuit.