SWITCHING POWER AMPLIFIER, AND SWITCHING CONTROL METHOD OF THE SWITCHING POWER AMPLIFIER

摘要

A reduction is made in signal distortion that occurs in an output signal of a PWM switching power amplifier due to noise disturbances from a switching power supply. In a switching power amplifier that has a switching power supply unit 11 as a power supply, a clock signal S18 for controlling the switching of the switching power supply unit 11 is generated based on a clock signal S6 that is used to synchronize switching operations. The clock signal S18 has a clock repeated period that is an integer multiple of a repeated period t of the clock signal S6 and matches a timing at which a signal level of a PWM power signal S4 that is generated by the switching power amplifier is at the ground level. The switching of the switching power supply unit 11 is synchronized using the clock signal S18.