An electronic device, comprising a main processor, a plurality of memories, an audio/video processing circuit, and a processing system, wherein the main processor is respectively coupled to the plurality of memories and the audio/video processing circuit, wherein the plurality of memories includes a first memory configured to operate in a second power domain; the processing system configured to operate in a first power domain, and the processing system further comprising: a second memory configured to store sound data detected by a microphone; a memory access circuit configured to transfer the sound data from the second memory to the first memory according to a first command, in order to store the sound data as voice data; a voice activity detection circuit configured to output a human voice detection signal according to the sound data; and a first processing circuit configured to output a second command according to the human voice detection signal; and the main processor includes a second processing circuit configured to operate in the second power domain and is enabled by the second command to determine whether the voice data in the first memory matches a predetermined voice command, when the first processing circuit receives the human voice detection signal, one of the first processing circuit and the second processing circuit is configured to output the first command, and a power consumption to which the first power domain corresponds is lower than a power consumption to which the second power domain corresponds. the plurality of memories includes a first memory configured to operate in a second power domain; the processing system configured to operate in a first power domain, and the processing system further comprising: a second memory configured to store sound data detected by a microphone; a memory access circuit configured to transfer the sound data from the second memory to the first memory according to a first command, in order to store the sound data as voice data; a voice activity detection circuit configured to output a human voice detection signal according to the sound data; and a first processing circuit configured to output a second command according to the human voice detection signal; and the main processor includes a second processing circuit configured to operate in the second power domain and is enabled by the second command to determine whether the voice data in the first memory matches a predetermined voice command, when the first processing circuit receives the human voice detection signal, one of the first processing circuit and the second processing circuit is configured to output the first command, and a power consumption to which the first power domain corresponds is lower than a power consumption to which the second power domain corresponds. a second memory configured to store sound data detected by a microphone; a memory access circuit configured to transfer the sound data from the second memory to the first memory according to a first command, in order to store the sound data as voice data; a voice activity detection circuit configured to output a human voice detection signal according to the sound data; and a first processing circuit configured to output a second command according to the human voice detection signal; and the main processor includes a second processing circuit configured to operate in the second power domain and is enabled by the second command to determine whether the voice data in the first memory matches a predetermined voice command, when the first processing circuit receives the human voice detection signal, one of the first processing circuit and the second processing circuit is configured to output the first command, and a power consumption to which the first power domain corresponds is lower than a power consumption to which the second power domain corresponds.