Semiconductor device and electronic apparatus

A semiconductor device comprising:

• a first output terminal coupled to a first terminal of a first sound reproduction device;
• a second output terminal coupled to a second terminal of the first sound reproduction device;
• a third output terminal coupled to a first terminal of a second sound reproduction device;
• a fourth output terminal coupled to a second terminal of the second sound reproduction device;
• a first modulation circuit that, in a first operation mode, modulates a signal based on a first sound source signal to output a first modulated signal and a second modulated signal;
• a second modulation circuit that, in the first operation mode, modulates a signal based on a second sound source signal to output a third modulated signal and a fourth modulated signal;
• a test signal generation circuit that, in a second operation mode, modulates a test signal of which a frequency is changed in a frequency band set in advance, to generate a fifth modulated signal and a sixth modulated signal;
• a first amplification circuit that, in the first operation mode, outputs a first amplified signal obtained by amplifying the first modulated signal to the first output terminal and outputs a second amplified signal obtained by amplifying the second modulated signal to the second output terminal and that, in the second operation mode, outputs a third amplified signal obtained by amplifying the fifth modulated signal to the first output terminal and outputs a fourth amplified signal obtained by amplifying the sixth modulated signal to the second output terminal;
• a second amplification circuit that, in the first operation mode, outputs a fifth amplified signal obtained by amplifying the third modulated signal to the third output terminal and outputs a sixth amplified signal obtained by amplifying the fourth modulated signal to the fourth output terminal and that, in the second operation mode, outputs a seventh amplified signal obtained by amplifying the fifth modulated signal to the third output terminal and outputs an eighth amplified signal obtained by amplifying the sixth modulated signal to the fourth output terminal;
• a first peak frequency detection circuit that, in the second operation mode, measures a potential difference between the first output terminal and the second output terminal to detect a first peak frequency that is a frequency of the test signal at which an impedance of the first sound reproduction device reaches a peak;
• a second peak frequency detection circuit that, in the second operation mode, measures a potential difference between the third output terminal and the fourth output terminal to detect a second peak frequency that is a frequency of the test signal at which an impedance of the second sound reproduction device reaches a peak;
• and
• a determination circuit that determines whether or not a difference between the first peak frequency and the second peak frequency is included in a predetermined reference frequency difference range.