| 摘要 |
Mobile devices such as mobile phones have always-on modes using sensors which respond to changes in the environment. A mobile device (200, 300, 400) is described comprising a loudspeaker (38); a controller (46) having an input (42) coupled to the loudspeaker (38). The controller (46) is operable in a first mode of operation to detect an electrical signal generated by the loudspeaker (38) in response to an acoustic input signal. This signal can be used to activate further circuitry. Using a loudspeaker as an acoustic sensor may reduce the power consumption of the mobile device. |
