Control device, control method, and power supply device

A power supply device comprising:

• a power supply circuit that controls an output voltage using a switching element;
• a generation unit that generates a reference signal;
• a pulse width modulation unit that generates a pulse width modulation signal that is output to the switching element by comparing the reference signal with a carrier signal;
• and
• a switching unit that switches a frequency of the carrier signal by changing amplitude of the carrier signal, wherein
• the generation unit includes a control circuit that generates the reference signal based on the output voltage of the power supply circuit, a frequency of the carrier signal before the switching, and the frequency of the carrier signal after the switching.

A control method comprising:

• controlling an output voltage of a power supply circuit using a switching element;
• generating a reference signal;
• generating a pulse width modulation signal that is output to the switching element by comparing the reference signal with a carrier signal;
• and
• switching a frequency of the carrier signal by changing amplitude of the carrier signal, wherein
• in the generating of the reference signal, the reference signal is generated based on the output voltage of the power supply circuit, a frequency of the carrier signal before the switching, and the frequency of the carrier signal after the switching.