Touch controller having increased sensing sensitivity, and display driving circuit and display device and system having the touch controller

Abstract

A touch controller includes a touch data generator that is connected to a plurality of sensing lines, the touch data generator sensing a change in capacitance of a sensing unit connected to each of the sensing lines and generating touch data by processing the sensing signal corresponding to the result of sensing; and a signal processor that controls a timing of generating the touch data by receiving at least one piece of timing information for driving a display panel from a timing controller, and then providing either the timing information or a signal generated from the timing information as a control signal to the touch data generator.

1 . A touch data generator configured for use within a touch screen controller (TSC) in a touch display device comprising a touch screen panel, and a display driving circuit (DDI), wherein the touch data generator comprises:
 an amplifier comprising a positive input terminal receiving an alternating reference voltage, a negative input terminal receiving a sensor input, an output terminal providing an output voltage, and a resistance-capacitance (RC) feedback circuit biasing the amplifier,   wherein the sensor input comprises a sensor capacitance including a touch capacitance and a capacitive background noise component, and   the amplifier is configured to remove the capacitive background noise component from the sensor input while amplifying the reference voltage in response to the touch capacitance.   
   
   
       2 . The touch data generator of  claim 1 , wherein the DDI comprises a timing controller configured to provide at least one control/timing signal to the TSC, and the reference voltage is synchronously related to the at least one control/timing signal. 
   
   
       3 . The touch data generator of  claim 2 , wherein the gain of the amplifier is about one plus the ratio of the touch capacitance and a capacitance of the feedback capacitor. 
   
   
       4 . The touch data generator of  claim 2 , further comprising:
 a sample and hold circuit configured to receive the output voltage, and an analog-to-digital converter configured to receive an output from the sample and hold circuit and generate sensor data related to the touch capacitance of the sensor input.   
   
   
       5 . The touch data generator of  claim 2 , wherein the capacitive background noise component is a horizontal parasitic capacitance arising from operation of the touch screen. 
   
   
       6 . The touch data generator of  claim 2 , wherein the capacitive background noise component is a vertical parasitic capacitance arising from operation of the touch screen in relation to an applied control voltage, and the touch data generator further comprises a cancellation capacitor connected between the negative input terminal of the amplifier and a cancellation control voltage. 
   
   
       7 . The touch data generator of  claim 6 , wherein the cancellation control voltage is synchronously related to the reference voltage by a factor controlled within the operation of the TSC to remove the vertical parasitic capacitance. 
   
   
       8 . The touch data generator of  claim 2 , wherein the capacitive background noise component comprises a vertical parasitic capacitance and a horizontal parasitic capacitance arising from operation of the touch screen, and the touch data generator further comprises a cancellation capacitor connected between the negative input terminal of the amplifier and a cancellation control voltage. 
   
   
       9 . The touch data generator of  claim 8 , wherein the cancellation control voltage is synchronously related to the reference voltage by a factor controlled within the operation of the TSC to remove the capacitive background noise component. 
   
   
       10 . The touch data generator of  claim 2 , wherein the capacitive background noise component comprise a vertical parasitic capacitance arising from operation of the touch screen in relation to an applied control voltage, and a horizontal parasitic capacitance arising from operation of the touch screen, and the touch data generator further comprises a cancellation capacitor connected between the negative input terminal of the amplifier and a cancellation control voltage. 
   
   
       11 . The touch data generator of  claim 10 , wherein the cancellation control voltage is synchronously related to the reference voltage. 
   
   
       12 . The touch data generator of  claim 2 , further comprising:
 a signal processor configured to receive the at least one control/timing signal from the timing controller.   
   
   
       13 . The touch data generator of  claim 4 , further comprising:
 a signal processor configured to receive the at least one control/timing signal from the timing controller, generate a sample and hold control signal synchronously related to the at least one control/timing signal, and apply the sample and hold control signal to the sample and hold circuit to control operation of the sample and hold circuit.   
   
   
       14 . A touch data generator configured for use within a touch screen controller (TSC) in a touch display device comprising a touch screen panel, and a display driving circuit (DDI), wherein the touch data generator comprises:
 driving and sensing control circuit detecting a sensor input and passing the detected sense input to an amplifier, wherein the sensor input comprises a touch capacitance and a capacitive background noise component;   the amplifier comprises a positive input terminal receiving an alternating reference voltage, a negative input terminal receiving the sensor input, an output terminal providing an output voltage, and a resistance-capacitance (RC) feedback circuit biasing the amplifier,   the amplifier is configured to remove the capacitive background noise component from the sensor input while amplifying the reference voltage in response to the touch capacitance, and   the DDI comprises a timing controller configured to provide at least one control/timing signal to the TSC, such that the reference voltage is synchronously related to the at least one control/timing signal.   
   
   
       15 . The touch data generator of  claim 14 , wherein the driving and sensing circuit comprises a plurality of sense lines respectively incorporating a sense line switch, wherein each one of the plurality of sense lines and corresponding sense line switches forms a sensor input channel, and each sensor input channel is sequentially switched onto the negative input terminal of the amplifier. 
   
   
       16 . The touch data generator of  claim 1 , wherein the display driving circuit is configured to drive a liquid crystal display panel, a plasma display panel, a light emitting diode display panel, or an organic light emitting display panel. 
   
   
       17 . A method operating a touch screen controller (TSC) in a touch display device comprising a touch screen panel and a display driving circuit (DDI), the method comprising:
 coupling a positive input terminal of an amplifier to an alternating reference voltage;   coupling a negative input terminal of the amplifier to a driving and sensing control circuit to receive a sensor input, wherein the sensor input comprises a touch capacitance and a capacitive background noise component; and   biasing the amplifier with a resistance-capacitance (RC) feedback circuit to amplify the reference voltage in response to the touch capacitance while removing the capacitive background noise component.   
   
   
       18 . The method of  claim 17 , wherein the reference voltage is synchronously related to at least one control/timing signal provided to the TSC by the DDI. 
   
   
       19 . The method of  claim 17 , wherein the reference voltage is amplified with a gain approximately equal to one plus the ratio of the touch capacitance and a capacitance of a feedback capacitor in the RC feedback circuit. 
   
   
       20 . The method of  claim 17 , wherein the capacitive background noise component is at least one of a horizontal parasitic capacitance arising from operation of the touch screen, and a vertical parasitic capacitance arising from operation of the touch screen in relation to an applied control voltage. 
   
   
       21 . The method of  claim 17 , further comprising:
 coupling a cancellation capacitor between the negative input terminal of the amplifier and a cancellation control voltage.   
   
   
       22 . The method of  claim 21 , wherein the cancellation control voltage is synchronously related to the reference voltage. 
   
   
       23 . The method of  claim 22 , wherein the capacitive background noise component comprises a horizontal parasitic capacitance arising from operation of the touch screen and a vertical parasitic capacitance arising from operation of the touch screen in relation to an applied control voltage. 
   
   
       24 . A touch display device, comprising:
 a display;   a display driving circuit (DDI) configured to control operation of the display;   a touch screen;   a touch screen controller (TSC) configured to control operation of the touch screen, wherein the TSC comprises a touch data generator configured to generate sense data corresponding to sensor input related to user-defined touch data received via the touch screen, the touch data generator comprising:
 an amplifier comprising a positive input terminal receiving an alternating reference voltage, a negative input terminal receiving the sensor input, an output terminal providing an output voltage, and a resistance-capacitance (RC) feedback circuit biasing the amplifier, 
 wherein the sensor input comprises sensor capacitance including a touch capacitance and a capacitive background noise component, and 
 the amplifier is configured to remove the capacitive background noise component from the sensor input while amplifying the reference voltage in response to the touch capacitance. 
   
   
   
       25 . The touch display device of  claim 24 , wherein the DDI comprises a timing controller configured to provide at least one control/timing signal to the TSC, and the reference voltage is synchronously related to the at least one control/timing signal. 
   
   
       26 . The touch display device of  claim 25 , wherein the gain of the amplifier is about one plus the ratio of the touch capacitance and a capacitance of a feedback capacitor in the RC feedback circuit. 
   
   
       27 . The touch display device of  claim 25 , wherein the touch data generator further comprises a sample and hold circuit configured to receive the output voltage, and an analog-to-digital converter configured to receive an output from the sample and hold circuit and generate sensor data corresponding to the touch capacitance. 
   
   
       28 . The touch display device of  claim 25 , wherein the capacitive background noise component is a horizontal parasitic capacitance arising from operation of the touch screen. 
   
   
       29 . The touch display device of  claim 25 , wherein the capacitive background noise component is a vertical parasitic capacitance arising from operation of the touch screen in relation to an applied control voltage, and the touch data generator further comprises a cancellation capacitor connected between the negative input terminal of the amplifier and a cancellation control voltage. 
   
   
       30 . The touch display device of  claim 29 , wherein the cancellation control voltage is synchronously related to the reference voltage by a factor controlled within the operation of the TSC to remove the vertical parasitic capacitance. 
   
   
       31 . The touch display device of  claim 25 , wherein the display is a liquid crystal display panel, a plasma display panel, a light emitting diode display panel, or an organic light emitting display panel. 
   
   
       32 - 65 . (canceled)