| 摘要 |
PROBLEM TO BE SOLVED: To provide a class D amplifier that keeps from adding to a cost even if increasing an upper limit of a maximum frequency, and keeps an output from becoming unstable because of LC resonance.SOLUTION: The class D amplifier includes: a first output circuit having first and second switching devices connected in series between a first power line for feeding a first potential and a second power line for feeding a second potential lower than the first potential, and adapted to operate complementarily to each other; a first capacitor connected between the first power line and the second power line; a pulse width modulator for generating a pulse-width-modulated switching signal on the basis of a triangular wave and an audio signal to feed the first output circuit; and a slew rate limiting amplifier connected to an input section of the pulse width modulator fed with the audio signal, and limiting a slew rate of an output. A sounding device is connected in series with an inductor connected to a first output node of the first output circuit, and configures an LC filter together with the inductor. |
