Abstract: A power detection method applied to a peripheral apparatus is provided. The method includes the following steps. First, a power signal is received from a data communication interface. Next, it is determined that whether the power signal is able to drive a main function device of the peripheral apparatus. Then, according to the determination result, the power signal is selectively provided to the main function device to drive the main function device.

Abstract: An electronic apparatus includes a first power source input terminal configured to receive a first driving voltage or a second driving voltage, wherein the second driving voltage is greater than the first driving voltage; a second power source input terminal configured to receive the first driving voltage or the second driving voltage; a protection circuit connected to the first power source input terminal; a first voltage circuit connected to the protection circuit and driven by the first driving voltage; and a second voltage circuit connected to the second power source input terminal and driven by the second driving voltage; wherein the second driving voltage is blocked by the protection circuit and not further transmitted to the first voltage circuit while the second driving voltage is inputted to the first power source input terminal.

Abstract: An external optical disc drive, connected to a bus from which a supplying voltage and a supplying current are outputted, includes: a voltage detector connected to the bus for receiving and detecting the supplying voltage; a digital signal processor connected to the voltage detector; a motor driver connected to the digital signal processor; and a spindle motor connected to the motor driver; wherein a speed-control signal, for informing the digital signal processor to lower the speed of the spindle motor via the motor driver, is outputted to the digital signal processor from the voltage detector while the supplying voltage is detected lower than a threshold voltage.

Abstract: A power detection method applied to a peripheral apparatus is provided. The method includes the following steps. First, a power signal is received from a data communication interface. Next, it is determined that whether the power signal is able to drive a main function device of the peripheral apparatus. Then, according to the determination result, the power signal is selectively provided to the main function device to drive the main function device.

Abstract: A sequential control circuit operates according to an input signal. When the input signal is determined at a first state, the sequential control circuit asserts a plurality of control signals in a predetermined sequence. When the input signal is determined at a second state, the sequential control circuit de-asserts the plurality of control signals in a sequence reverse to the predetermined sequence.

Abstract: A sequential control circuit operates according to an input signal. When the input signal is determined at a first state, the sequential control circuit asserts a plurality of control signals in a predetermined sequence. When the input signal is determined at a second state, the sequential control circuit de-asserts the plurality of control signals in a sequence reverse to the predetermined sequence.

Abstract: The present invention discloses a mute circuit of an audio device for suppressing audio signals during the transients of power switching. A mute circuit for an amplifier having at least an audio output terminal includes at least one bypass device, each of which has a controlling terminal and is capable of providing a path from the audio output terminal to a ground when the controlling terminal is turned on; a power-on controlling circuit for turning on the controlling terminal of the bypass device during a first period of time after a power-on transient; a fixed-voltage supply for stopping the amplifier during the power-on transient according to a control of a controlling terminal of an input/output port; and a power-off controlling circuit for turning on the controlling terminal of the bypass device by utilizing a voltage of a capacitor during a second period of time after a power-off transient.