Patent ID: 8995680
Filing Date: 2015-03-31
Classification: H04R

Abstract:
1. A power-saving monitoring circuit, applied to an electrostatic earphone having a thin film and a plurality of electrode plates, comprising: a power supply unit, for generating a first voltage; an input unit, for receiving an audio frequency signal; a detection unit, coupled to the input unit, for detecting the audio frequency signal received by the input unit, and selectively generating a control signal corresponding to the audio frequency signal according to a voltage amplitude of the audio frequency signal; a switch unit, having a control terminal, an input terminal and an output terminal, and coupled to the power supply unit through the input terminal, for receiving a control signal through the control terminal, and controlling a conducting state between the input terminal and the output terminal according to the control signal to transmit the first voltage selectively from the input terminal to the output terminal; a driving module, coupled to the switch unit, for selectively converting the first voltage into a second voltage according to the conducting state to driving the thin film, wherein the second voltage has a voltage value greater than the voltage value of the first voltage; an output unit, coupled to the input unit, for outputting the audio frequency signal to the electrode plates; and a latch unit, coupled to the detection unit and the switch unit, and generating other control signal for controlling the switch unit after the latch unit receives the control signal, wherein a voltage level of the other control signal is maintained, set, or reset by the latch unit according to the control signal.