Patent ID: 7804293

Claim:
A power supply apparatus that supplies a power supply current to an electronic device, comprising: a current output section that outputs an output current that includes the power supply current; a low pass filter that receives an output voltage of the current output section and allows a low frequency component with a frequency lower than a preset cutoff frequency to pass through; an excess voltage restricting load section that is connected between the current output section and a ground, in parallel with the electronic device, and that consumes an excess voltage restricting current, which is at least a portion of the output current from the current output section, when a load is turned on and stops the consumption of the excess voltage restricting current when the load is turned off; and an excess voltage restricting load control section that keeps the excess voltage restricting load section turned off when the output voltage of the current output section is less than an upper reference voltage, which is obtained by adding together a voltage output by the low pass filter and a preset upper offset voltage, and that turns on the excess voltage restricting load section when the output voltage becomes greater than or equal to the upper reference voltage.