| abstract |
A vehicle warning device (200) with a novel structure is provided. The vehicle alarm device (200) includes a sound source detection device (110), and the sound source detection device (110) includes a plurality of microphones (116) and a delay circuit (117). As the transistor constituting the signal holding circuit (22) in the delay circuit (117), a transistor (OS transistor) including an oxide semiconductor is used. The external sound is acquired by the sound source detection device (110), and the sound source position of the external sound is specified. When it is determined from the relative speed between the sound source at the specified position and the vehicle, and the like that the sound source has a high probability of hitting the vehicle and the danger is high, an audio signal for drawing the occupant's attention is output. |