Power supply apparatus and electronic equipment

To provide a power supply apparatus that replaces a dry battery by detecting electric field energy in a free space, rectifying the energy, extracting the energy as electric power, and accumulating the electric power. In particular, there is provided a power supply apparatus (10) that is useful for a portable electronic equipment (100). An electromagnetic energy conversion unit (11) collects a radio wave propagating in the air and converts collected electromagnetic energy into electric power. A rectifying unit (13) generates electric power having a DC waveform by rectifying electric power having an AC waveform and charges the rectified electric power having the DC waveform into a secondary battery (15). An electric load (X100) is supplied with the rectified electric power having the DC waveform or with electric power having a DC waveform discharged from the secondary battery (15).