Abstract: A capacitive touch sensor includes a touch interface, a switch, and a sensing circuit. The switch circuit switches based on sensing conditions of self-capacitance and mutual capacitance. The sensing circuit is used for both the self-capacitance mode and the self-capacitance mode to simplify circuit structure and save circuit area and power consumption. The output sensing voltage from the sensing circuit is stable. A differential mode is designed to improve noise interference and enhance accuracy of judging the touch effect. Then, the self-capacitance mode is utilized for the areas of possible touches to save operation time for the capacitance mode.

Abstract: A capacitive touch sensor includes a touch interface, a switch, and a sensing circuit. The switch circuit switches based on sensing conditions of self-capacitance and mutual capacitance. The sensing circuit is used for both the self-capacitance mode and the self-capacitance mode to simplify circuit structure and save circuit area and power consumption. The output sensing voltage from the sensing circuit is stable. A differential mode is designed to improve noise interference and enhance accuracy of judging the touch effect. Then, the self-capacitance mode is utilized for the areas of possible touches to save operation time for the capacitance mode.

Abstract: The present invention discloses a reference circuit with temperature compensation, which is characterized in that a current output circuit is designed to receive a reference voltage from a bias voltage generation circuit, generate two reference currents with opposite temperature variation characteristics, and then merge them into a compensated current with temperature compensation. In addition, a voltage output circuit is designed to receive a reference voltage from a bias voltage generation circuit, which includes several field-effect transistors operating in saturation regions, and a precision voltage increases with threshold voltages of the field-effect transistors to compensate for the temperature variation. Resistors can be incorporated or sizes of the field effect transistors can be changed to adjust the output current, output voltage or the temperature variation characteristics.

Abstract: The present invention discloses a reference circuit with temperature compensation, which is characterized in that a current output circuit is designed to receive a reference voltage from a bias voltage generation circuit, generate two reference currents with opposite temperature variation characteristics, and then merge them into a compensated current with temperature compensation. In addition, a voltage output circuit is designed to receive a reference voltage from a bias voltage generation circuit, which includes several field-effect transistors operating in saturation regions, and a precision voltage increases with threshold voltages of the field-effect transistors to compensate for the temperature variation. Resistors can be incorporated or sizes of the field effect transistors can be changed to adjust the output current, output voltage or the temperature variation characteristics.