Patent attributes
A button device comprising a voltage source and a plurality of buttons is provided. The button device further comprises: a charging module, a loading capacitor, a control module, and an MCU. The charging module provides a plurality of charging paths. At least one charging path is connected when at least one button is pressed. The loading capacitor coupled to the charging module obtains the electric power from the connected charging path to generate a charged signal. The control module sends a control signal through a connected control capacitor when the button is pressed to generate the control signal. The MCU receives the control signal to calculate a charging time and determines which button is pressed according to the charging time. The MCU stops calculating the charging time when the charged signal reaches a first predetermined voltage. Each charging path corresponds to different charging time.
