A mobile terminal including a wireless communication processor configured to provide wireless communication; a microphone; a low-power image sensor configured to detect a subject based on a black and white image sensed by the low-power image sensor; and a controller configured to control the microphone to be in an inactivate state, in response to detecting a face image included in the black and white image sensed by the low-power image sensor, and switch the microphone from the inactive state to an active state and execute a voice recognition function to receive voice information from the subject.