US 12,463,608 B2
Sound output device
Minoru Matsuyama, Fukushima (JP)
Assigned to ALPS ALPINE CO., LTD., Tokyo (JP)
Filed by ALPS ALPINE CO., LTD., Tokyo (JP)
Filed on Apr. 5, 2023, as Appl. No. 18/131,158.
Claims priority of application No. 2022-065494 (JP), filed on Apr. 12, 2022.
Prior Publication US 2023/0327617 A1, Oct. 12, 2023
Int. Cl. H03F 3/217 (2006.01)
CPC H03F 3/2175 (2013.01) [H03F 3/2171 (2013.01); H03F 2200/03 (2013.01); H03F 2200/351 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A sound output device having a function of detecting connection or disconnection of a speaker, the sound output device comprising:
a class D amplifier configured to receive a sound input signal and to generate a sound output signal that is obtained by amplifying the sound input signal;
a speaker configured to output a sound in response to the sound output signal; and
a detection unit configured to detect connection or disconnection of the speaker, wherein
the detection unit includes:
a first filter configured to remove a high-frequency component of the sound input signal,
a second filter configured to remove a high-frequency component of the sound output signal, and
a comparison unit configured to compare the sound input signal from which the high-frequency component has been removed by the first filter with the sound output signal from which the high-frequency component has been removed by the second filter, and to determine connection or disconnection of the speaker on the basis of a comparison result.