TWI775403B - Control circuit and display apparatus - Google Patents

Abstract

A control circuit including a first input-output pin, a second input-output pin, a sensing circuit and a display controller is provided. The first input-output pin is configured to be coupled to a first input pin of a display device and a first sensing pin of a capacitive touch device. The second input-output pin is configured to be coupled to a second input pin of the display device and a second sensing pin of the capacitive touch device. The display controller provides a first driving signal to the display device via the first input-output pin and providing a second driving signal to the display device via the second input-output pin in a display period. In a sensing period, the voltage level of the first input-output pin is equal to a first predetermined level, and the sensing circuit detects the voltage of the second input-output pin.

Description

Control circuit and display equipment

The present invention relates to a control circuit, and more particularly, to a control circuit coupled to a display device and a touch device.

With the advancement of technology, there are more and more types and functions of electronic devices. Most electronic devices have an input device and an output device. A control device in the electronic device controls the operation of the electronic device according to the information received by the input device, and presents specific information through the output device. Touch devices and display devices are common input devices and output devices. However, since the touch device and the display device each have a large number of pins, the number of pins of the control device must be greater than the sum of the pins of the touch device and the display device in order to couple the touch control device and the display device. Thus, the available space inside the electronic device is reduced.

The invention provides a control circuit, which includes a first input and output pin, a second input and output pin, a sensing circuit and a display controller. The first input and output pins are used for coupling to a first input pin of a display device and a first sensing pin of a capacitive touch device. The second input and output pins are used for coupling to a second input pin of the display device and a second sensing pin of the capacitive touch device. The sensing circuit determines whether the capacitive touch device is touched according to the voltages of the first and second input and output pins. During a display period, the display controller provides a first driving signal to the display device through the first input and output pins, and provides a second driving signal to the display device through the second input and output pins. During a sensing period, the first input and output pins are equal to a predetermined level, and the sensing circuit detects the voltage of the second input and output pins.

The present invention further provides a display device including a display device, a capacitive touch device and a control circuit. The display device has a first input pin and a second input pin. The capacitive touch device has a first sensing pin and a second sensing pin. The control circuit includes a first input and output pin, a second input and output pin, a sensing circuit and a display controller. The first input and output pins are coupled to the first input pins and the first sensing pins. The second input and output pins are coupled to the second input pins and the second sensing pins. The sensing circuit determines whether the capacitive touch device is touched according to the voltages of the first and second input and output pins. During a display period, the display controller provides a first driving signal to the display device through the first input and output pins, and provides a second driving signal to the display device through the second input and output pins. During a sensing period, the sensing circuit sets the first input/output pin to be equal to a preset level, and detects the voltage of the second input/output pin.

In order to make the objects, features and advantages of the present invention more obvious and easy to understand, the following specific embodiments are given and described in detail in conjunction with the accompanying drawings. The present specification provides different embodiments to illustrate the technical features of different embodiments of the present invention. Wherein, the configuration of each element in the embodiment is for illustration, and not for limiting the present invention. In addition, parts of the reference numerals in the drawings in the embodiments are repeated for the purpose of simplifying the description, and do not mean the correlation between different embodiments.

FIG. 1 is a schematic diagram of the operating system of the present invention. As shown in the figure, the operating system 100 includes a display device 110 , a capacitive touch device 120 and a control circuit 130 . The display device 110 has pins PN ₁ -PN ₄ and a display area 111 . The display area 111 presents a picture according to the voltage levels of the pins PN ₁ -PN ₄ . The present invention does not limit the number of pins of the display device 110 . In addition, the present invention does not limit the type of the display device 110 either. In a possible embodiment, the display device 110 is a super twisted liquid-crystal display panel (STN LCD panel).

The capacitive touch device 120 includes regions 121 - 124 , sensing elements 125 - 128 , and pins PN ₅ -PN ₈ , which are not intended to limit the present invention. In other embodiments, the capacitive touch device 120 may have other numbers of regions, sensing elements, and pins. The present invention does not limit the type of the capacitive touch device 120 . In a possible embodiment, the capacitive touch device 120 is a touch keyboard or a touch pad.

In this embodiment, the sensing element 125 is disposed in the area 121 to determine whether the area 121 is touched, the sensing element 126 is disposed in the area 122 to determine whether the area 122 is touched, the sensing element 127 The sensing element 128 is disposed in the area 123 to determine whether the area 123 is touched, and the sensing element 128 is disposed in the area 124 to determine whether the area 124 is touched. In a possible embodiment, the sensing elements 125 - 128 are capacitive sensors. The pin _PN5 outputs the sensing result of the sensing element 125 . The pin _PN6 outputs the sensing result of the sensing element 126 . Pins PN ₇ respectively output the sensing results of the sensing elements 127 . Pins PN ₈ respectively output the sensing results of the sensing elements 128 . Taking the sensing element 125 as an example, when the area 121 is not touched, the capacitance of the sensing element 125 does not change. _At this time, the voltage V _PN5 of the pin PN5 may be equal to a reference voltage. However, when the area 121 is touched, the capacitance of the sensing element 125 will change (may become larger), therefore, the voltage V _PN5 of the pin _PN5 will not be equal to the reference voltage. For example, the voltage V _PN5 of pin _PN5 may be less than the reference voltage.

The control circuit 130 includes an image driver 131 , a micro-control circuit 132 , a sensing circuit 133 , a transmission circuit 134 and input/output pins 135 - 138 . The image driver 131 is used for driving the display device 110 . In this embodiment, the image driver 131 generates the driving signals SD1 ˜ SD4 , but the invention is not limited thereto. In other embodiments, the image driver 131 may generate more or less driving signals. The present invention does not limit the circuit structure of the image driver 131 . In a possible embodiment, the image driver 131 is a liquid crystal driver (LCD driver). In another possible embodiment, the image driver 131 is a COM/SEG driver for generating COM/SEG waveforms.

The sensing circuit 133 is used to detect whether the capacitive touch device 120 is touched and the touch position. The present invention does not limit how the sensing circuit 133 detects whether the capacitive touch device 120 is touched. In a possible embodiment, the sensing circuit 133 first provides a reference voltage DK to the pins PN ₅ ˜PN ₈ of the capacitive touch device 120 , and then detects whether the voltage levels of the pins PN ₅ ˜PN ₈ occur. Variety. When the voltage level of pins PN ₅ ~PN ₈ changes, it means that the corresponding area is touched. For example, when the voltage V _PN5 of the pin PN ₅ is not equal to the reference voltage DK, it means that the region 121 corresponding to the pin PN ₅ is touched. Conversely, when the voltage V _PN5 of the pin PN ₅ is equal to the reference voltage DK, it means that the region 121 corresponding to the pin PN ₅ is not touched. In some embodiments, the reference voltage DK is less than 1 volt.

The transmission circuit 134 includes switching circuits SW1 and SW2. The switching circuit SW1 is coupled between the image driver 131 and the input and output pins 135-138, and is controlled by a switching signal SEL. When the switching signal SEL turns on the switching circuit SW1, the switching circuit SW1 transmits the driving signals SD1-SD4 to the input and output pins 135-138. At this time, the input and output pins 135 - 138 are used as output pins for outputting the driving signals SD1 - SD4 to the display device 110 .

The switching circuit SW2 is coupled between the sensing circuit 133 and the input and output pins 135-138, and is controlled by the switching signal SEL. When the switching signal SEL turns on the switching circuit SW2, the switching circuit SW2 may first transmit the reference voltage DK to the input and output pins 135-138, and then transmit the voltages V _PN5 -V _PN8 of the pins PN5 _{- PN8} to the sensing circuit 133.

In this embodiment, the input and output pins 135 - 138 are used to transmit analog signals. In other words, the driving signals SD1 to SD4 and the voltages V _PN5 to V _PN8 are analog signals. In addition, in this embodiment, the display device 110 and the capacitive touch device 120 share the input and output pins 135 - 138 , so the number of input and output pins of the control circuit 130 can be reduced. In other embodiments, the display device 110 and the capacitive touch device 120 may share more or less input and output pins.

Since the characteristics of the input and output pins 135 to 138 are the same, the following content takes the input and output pin 135 as an example. As shown in FIG. 1 , the input/output pin 135 is coupled to the pin PN _{1 of the display device 110 and the pin PN 5 of} the capacitive touch device 120 . When the switching circuit SW1 is turned on, the I/O pin 135 transmits the driving signal SD1. When the switching circuit SW2 is turned on, the I/O pin 135 transmits the reference voltage DK and the voltage V _PN5 of the pin PN ₅ .

In a possible embodiment, the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ are one-third or one-quarter of the amplitudes of the driving signals SD1 ˜SD4 . Therefore, even if the pins PN ₅ ˜PN ₈ are coupled to the pins PN ₁ ˜PN ₄ , the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ will not affect the images displayed by the display device 110 .

For example, it is assumed that the maximum voltage of the driving signals SD1 ˜ SD4 is 4 volts (V). In this example, the voltages of pins PN ₅ ~PN ₈ V _PN5 ~V _PN8 have a maximum voltage of about 1.3V (that is, one third of the voltage of the driving signal SD1 ~ SD4) or 1V (that is, the voltage of the driving signal SD1 quarter of the voltage). Since the voltages V _{PN5 ˜V PN8} are very small, the images displayed by the display device 110 will not be disturbed by the voltages V _{PN5 ˜V PN8} . In other embodiments, the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ are less than 1V.

The micro-control circuit 132 generates the switching signal SEL for controlling the switching circuits SW1 and SW2. In this embodiment, the switching circuits SW1 and SW2 are not turned on at the same time. For example, when the micro-control circuit 132 turns on the switching circuit SW1, the micro-control circuit 132 does not turn on the switching circuit SW2. When the micro-control circuit 132 turns on the switching circuit SW2, the micro-control circuit 132 turns off the switching circuit SW1.

The present invention does not limit the circuit structure of the micro-control circuit 132 . In a possible embodiment, the microcontroller circuit 132 is a microcontroller (MCU). In this embodiment, the micro-control circuit 132 uses a single switching signal (eg, SEL) to control the switching circuits SW1 and SW2, but it is not intended to limit the present invention. In other embodiments, the micro-control circuit 132 uses two switching signals to control the switching circuits SW1 and SW2 respectively.

In other embodiments, the micro-control circuit 132 further triggers the image driver 131 and the sensing circuit 133 . When the video driver 131 is activated, the video driver 131 generates the driving signals SD1 - SD4 . At this time, the micro-control circuit 132 turns on the switching circuit SW1 and does not turn on the switching circuit SW2 through the switching signal SEL. Therefore, the input and output pins 135 - 138 output the driving signals SD1 - SD4 to the display device 110 . The display device 110 presents images according to the driving signals SD1 to SD4.

When the micro-control circuit 132 triggers the sensing circuit 133, the sensing circuit 133 generates the reference voltage DK. At this time, the micro-control circuit 132 turns on the switching circuit SW2 and does not turn on the switching circuit SW1 through the switching signal SEL. Therefore, the input and output pins 135 ˜ 138 first output the reference voltage DK to the sensing circuit 133 , and then provide the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ to the sensing circuit 133 . In this example, the sensing circuit 133 determines whether the regions 121 ˜ 124 are touched according to the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ .

In other embodiments, when the micro-control circuit 132 triggers the sensing circuit 133, the micro-control circuit 132 may instruct the image driver 131 to suspend generating the driving signals SD1-SD4. In some embodiments, the image driver 131 may continue to generate the driving signals SD1 - SD4 . However, since the micro-control circuit 132 does not conduct the switching circuit SW1, the switching circuit SW1 does not transmit the driving signals SD1-SD4 to the input and output pins 135-138. In this example, since the display device 110 has charge storage elements, the display device 110 can maintain the screen even if the driving signals SD1 to SD4 are not received.

In this embodiment, the time during which the switching circuit SW2 is turned on is shorter than the time during which the switching circuit SW1 is turned on. For example, the time that the switching circuit SW2 is turned on may be one tenth of the time that the switching circuit SW1 is turned on. Therefore, even if the switching circuit SW1 temporarily stops transmitting the driving signals SD1 ˜ SD4 , the images displayed by the display device 110 will not be disturbed by the voltages V _{PN5 ˜V PN9 of} the pins PN5 _˜PN8 . In a possible embodiment, the switching circuit SW1 is turned on for about 250 us, and the switching circuit SW2 is turned on for about 250 ns.

In addition, since the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ are very small, even if the display device 110 receives the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ , the picture displayed by the display device 110 will not change. It will not be affected by the voltages V _PN5 ~V _PN8 on pins PN ₅ ~PN ₈ . In a possible embodiment, the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ may be less than one-third of the driving signals SD1 ˜SD4 . In another embodiment, the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ may be less than a quarter of the driving signals SD1 ˜SD4 . In other embodiments, the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ are less than 1V.

The present invention does not limit when the micro-control circuit 132 turns on the switching circuit SW2. Assume that the display device 110 displays a plurality of frames in one second. In a possible embodiment, the micro-control circuit 132 turns on the switching circuit SW2 between the two frames presented by the display device 110 . In another possible embodiment, the micro-control circuit 132 turns on the switching circuit SW2 at least once during the time when the display device 110 presents one frame.

FIG. 2 is a possible schematic diagram of the transmission circuit 134 of the present invention. As shown in the figure, the switching circuit SW1 is coupled between the image driver 131 and the input and output pins 135-138, and has paths PA1-PA4. In this embodiment, the paths PA1 ˜ PA4 transmit the driving signals SD1 ˜ SD4 to the input and output pins 135 ˜ 138 according to the switching signal SEL.

For example, when the switching signal SEL turns on the paths PA1-PA4, the paths PA1-PA4 transmit the driving signals SD1-SD4 to the input and output pins 135-138. When the switching signal SEL does not conduct the paths PA1-PA4, the paths PA1-PA4 stop transmitting the driving signals SD1-SD4 to the input and output pins 135-138. The present invention does not limit the structure of the switching circuit SW1. In a possible embodiment, the switching circuit SW1 has a plurality of switches for providing paths PA1 ˜ PA4 . In this embodiment, the paths PA1 ˜ PA4 are turned on or off at the same time. In other embodiments, when one of the paths PA1 ˜ PA4 is turned on, at least one of the paths PA1 ˜ PA4 is not turned on.

The switching circuit SW2 has paths PA5 to PA8. The path PA5 is coupled between the sensing circuit 133 and the input and output pins 135 and transmits the reference voltage DK and the voltage V _PN5 of the pin PN ₅ according to the switching signal SEL. The path PA6 is coupled between the sensing circuit 133 and the input and output pins 136 and transmits the reference voltage DK and the voltage V _PN6 of the pin PN ₆ according to the switching signal SEL. The path PA7 is coupled between the sensing circuit 133 and the input/output pin 137, and transmits the reference voltage DK and the voltage V _PN7 of the pin PN ₇ according to the switching signal SEL. The path PA8 is coupled between the sensing circuit 133 and the input/output pin 138, and transmits the reference voltage DK and the voltage V _PN8 of the pin PN ₈ according to the switching signal SEL. For example, when the switching signal SEL turns on the paths PA5~PA8, the paths PA5~PA8 first transmit the reference voltage DK to the input and output pins ₁₃₅ ~ ₁₃₈ , and then transmit the voltages _V135 ~ _V138 of the pins PN5~PN8. Test circuit 133. When the switching signal SEL does not conduct the paths PA5 ˜ PA8 , the paths PA5 ˜PA8 stop transmitting the reference voltage DK and the voltages V ₁₃₅ ˜V ₁₃₈ . In this embodiment, the paths PA5 ˜ PA8 are turned on or off at the same time. In other embodiments, when one of the paths PA5 ˜ PA8 is turned on, the other one of the paths PA5 ˜ PA8 is not turned on.

In one embodiment, the paths coupled to the same input and output pins are not turned on at the same time. Taking the input/output pin 135 as an example, the input/output pin 135 is coupled to the paths PA1 and PA5. In this example, when the path PA1 is turned on, the path PA5 is not turned on. When the path PA5 is turned on, the path PA1 is not turned on. The present invention does not limit the structure of the switching circuit SW2. In a possible embodiment, the switching circuit SW2 has a plurality of switches for providing paths PA5 ˜ PA8 .

FIG. 3 is a possible schematic diagram of the sensing circuit of the present invention. The sensing circuit 133 includes sensing units 310 - 340 . The sensing unit 310 determines whether the area 121 of the capacitive touch device 120 is touched. The sensing unit 320 determines whether the area 122 of the capacitive touch device 120 is touched. The sensing unit 330 determines whether the area 123 of the capacitive touch device 120 is touched. The sensing unit 340 determines whether the area 124 of the capacitive touch device 120 is touched. Since the structures of the sensing units 310 to 340 are the same, only the structure and operation of the sensing unit 310 will be described below.

The sensing unit 310 includes capacitors Cmp, Cmn, a comparator 313 and a controller 314 . The capacitor Cmp is coupled between the node 311 and the non-inverting input terminal of the comparator 313 for providing a reference voltage DK. The capacitor Cmn is coupled between the inverting input terminal of the comparator 313 and the node 312 . In other embodiments, the capacitor Cmn may be coupled between the inverting input terminal of the comparator 313 and the node 311 . In this embodiment, the capacitors Cmp and Cmn are both variable capacitors.

The non-inverting input terminal of the comparator 313 is coupled to the capacitor Cmp for receiving the reference voltage DK. The inverting input terminal of the comparator 313 receives the voltage V _PN8 of the pin PN ₈ and is coupled to the capacitor Cmn. In this embodiment, the comparator 313 compares the reference voltage DK and the voltage V _PN8 to generate a comparison signal SCM.

The controller 314 determines whether a specific area (eg, the area 124 ) of the capacitive touch device 120 is touched according to the comparison signal SCM. In a possible embodiment, the controller 314 first generates the reference voltage DK, and then provides the reference voltage DK to the non-inverting input terminal of the comparator 313 . Then, the controller 314 learns whether a specific area of the capacitive touch device 120 is touched according to the voltage of the inverting input terminal of the comparator 313 . In this embodiment, the controller 314 knows the touch force according to the voltage of the inverting input terminal of the comparator 313 .

For example, in an initial period, the controller 314 first provides a predetermined voltage to the nodes 311 and 312 . Therefore, the capacitors Cmp and Cmn start to store charges for generating the reference voltage DK. At this time, the voltage of the inverting input terminal of the comparator 313 and the voltage of the non-inverting input terminal are approximately equal to the reference voltage DK. If the switch circuit SW2 is turned on, the switch circuit SW2 transmits the reference voltage DK to the pins PN ₅ -PN ₈ of the capacitive touch device 120 .

In this example, when the area 124 of the capacitive touch device 120 is touched, the capacitance of the sensing element 128 in the area 124 changes, so that the voltage V _PN8 of the pin PN ₈ changes and is no longer equal to the reference voltage DK. Since the voltage of the inverting input terminal (ie, V _PN8 ) of the comparator 313 is not equal to the voltage of the non-inverting input terminal (ie, DK), the controller 314 knows that the region 124 is touched.

In a possible embodiment, the controller 314 generates the adjustment signals SAp and SAn to adjust the capacitances of the capacitors Cmp and Cmn, so that the voltage of the inverting input terminal of the comparator 313 is again equal to the voltage of the non-inverting input terminal (ie DK) . After the voltage of the inverting input terminal of the comparator 313 is equal to the voltage of the non-inverting input terminal, the controller 314 can know the intensity of the touch action according to the adjustment range of the capacitances of the capacitors Cmp and Cmn. In a possible embodiment, the controller 314 generates a notification signal for notifying the microcontroller 132 of a touch event.

FIG. 4 is a possible schematic diagram of the display device 110 of the present invention. As shown in the figure, the display device 110 has pixels P ₁₁ -P ₄₄ , which are not intended to limit the present invention. In other embodiments, the display device 110 has more or fewer pixels. In this embodiment, the display device 110 is an active matrix (AM) liquid crystal display. In this example, the pixels P ₁₁ ˜P ₄₄ receive and store the data signals DA ₁ ˜DA ₄ according to the turn-on signals ST ₁ ˜ST ₄ . Taking the pixel P ₁₁ as an example, the pixel P ₁₁ receives and stores the data signal DA _{1 according to the turn-on signal ST 1 .} In a possible embodiment, the pixels P ₁₁ ˜P ₄₄ each have a storage capacitor (not shown) for storing the data signals DA ₁ ˜DA ₄ .

In a possible embodiment, the turn-on signals ST ₁ ˜ST ₄ are the driving signals SD1 ˜ SD4 . In this example, the data signals DA ₁ -DA ₄ may be generated by the video driver 131 . The image driver 131 may provide the data signals DA ₁ -DA ₄ to the display device 110 through other input and output pins. These input and output pins (ie, the input and output pins for transmitting the data signals DA ₁ -DA ₄ ) may or may not be coupled to the capacitive touch device 120 .

In another possible embodiment, the data signals DA1 _- DA4 are driving signals SD1 _- SD4. In this example, the image driver 131 may provide the turn-on signals ST ₁ to ST ₄ to the display device 110 through other input and output pins. These input and output pins (ie, the input and output pins for transmitting the turn-on signals ST ₁ -ST ₄ ) may or may not be coupled to the capacitive touch device 120 .

In other embodiments, the driving signals SD1 to SD4 are COM/SEG signals. In this example, the pixels P ₁₁ ˜P ₄₄ receive and store the data signals DA ₁ ˜DA ₄ according to the turn-on signals ST ₁ ˜ST ₄ and the COM/SEG signal.

In some embodiments, the display device 110 is a passive matrix (PM) display. In this example, the driving signals SD1 to SD4 are called common signals, and the data signals _DA1 to _DA4 are called segment signals. Using the potentials of the driving signals SD1 ˜ SD4 and the data signals DA ₁ ˜DA ₄ , the tilt angles of the liquid crystal molecules of the pixels P ₁₁ ˜P ₄₄ are changed, thereby changing the light transmittance of the display device 110 . In a possible embodiment, the pixels P ₁₁ to P ₄₄ do not have a memory function. Therefore, once the driving signals SD1 ˜ SD4 and the data signals DA ₁ ˜DA ₄ disappear, the liquid crystal molecules of the pixels P ₁₁ ˜P ₄₄ will return to their original positions.

In other embodiments, the display device 110 further has a driving circuit (not shown). In this example, the driving circuit may generate turn-on signals ST ₁ ˜ST ₄ or data signals DA ₁ ˜DA ₄ according to the driving signals SD1 ˜SD4 . In some embodiments, the driving circuit of the display device 110 generates the turn-on signals ST ₁ ˜ST ₄ and the data signals DA ₁ ˜DA ₄ according to the driving signals SD1 ˜SD4 .

In this embodiment, since the display device 110 and the capacitive touch device 120 share the input and output pins (eg, 135 - 138 ), the number of input and output pins of the control circuit 130 can be greatly reduced. Furthermore, since the voltages V _{PN5 ˜V PN8} of the pins PN ₅ ˜PN ₈ of the capacitive touch device 120 are much smaller than the voltages of the pins PN ₁ ˜PN ₄ of the display device 110 , the display device 110 is not affected by Influence of voltage V _PN5 ~V _PN8 . Furthermore, the output time of the voltages V _PN5 -V _PN8 from the capacitive touch device 120 is very short, so the voltages V _PN5 -V _PN8 do not affect the display device 110 .

FIG. 5A is another schematic diagram of the operating system of the present invention. As shown in the figure, the operating system 500 includes a display device 510 , a capacitive touch device 520 and a control circuit 530 . In one possible embodiment, the operating system 500 is a display system. In this example, the display device 510 , the capacitive touch device 520 and the control circuit 530 are integrated into a display device.

The display device 510 has a display area 511, input pins SEG0-SEG3 and COM0-COM3. In a possible embodiment, each of the input pins SEG0 - SEG3 receives a segment signal, and each of the input pins COM0 - COM3 receives a common signal. The display area 511 has a plurality of pixels (not shown). Each pixel is coupled to one of the input pins SEG0-SEG3 and one of the pins COM0-COM3. The corresponding pixel is activated by the voltage difference between one of the input pins SEG0~SEG3 and one of the pins COM0~COM3.

The present invention does not limit the type of the display device 510 . In a possible embodiment, the display device 510 is an active matrix display. In this example, each pixel may include a driving transistor (not shown) and a storage capacitor (not shown). The corresponding pixel can be activated by charging the storage capacitor by the driving transistor.

In another possible embodiment, the display device 510 is a passive matrix display, such as a twisted nematic liquid-crystal display panel (TN LCD) panel or a super twisted nematic liquid crystal (super twisted nematic liquid crystal display panel) crystal display panel; STN LCD) panel. In this example, each pixel of the passive matrix display may have a liquid crystal capacitor, but no drive transistor and storage capacitor. One end of the liquid crystal capacitor is directly connected to one of the input pins SEG0 to SEG3, and the other end of the liquid crystal capacitor is directly connected to one of the input pins COM0 to COM3.

In other embodiments, the display device 510 is a passive matrix organic light emitting diode (PMOLED) display. In this example, each pixel of the display device 510 has only one light-emitting diode, without a driving transistor and a storage capacitor. One end (eg, anode) of the light-emitting diode is directly connected to one of the input pins SEG0 to SEG3, and the other end (eg, the cathode) of the light-emitting diode is directly connected to one of the input pins COM0 to COM3.

The capacitive touch device 520 includes sensing regions 521 - 528 , sensing pins AN0 - AN3 and BN0 - BN3 . In a possible embodiment, each sensing area has at least one sensing element, such as a touch sensor. The touch sensor is used for judging whether the corresponding sensing area is touched. Since the characteristics of the sensing elements in the sensing regions 521 to 528 are the same as the characteristics of the sensing elements 125 to 128 in FIG. 1 , detailed descriptions are omitted.

The sensing pins AN0 - AN3 and BN0 - BN3 output the signals generated by the sensing elements in the sensing regions 521 - 528 . In a possible embodiment, each sensing area has a sensing element. In this example, each of the sensing pins AN0 - AN3 and BN0 - BN3 corresponds to a sensing element. For example, the sensing regions 521 ˜ 524 are electrically connected to the sensing pins BN0 ˜ BN3 , respectively. The sensing areas 525 - 528 are electrically connected to the sensing pins AN0 - AN3 respectively. In this embodiment, the sensing pins AN0 ˜ AN3 are electrically connected to the input pins SEG3 ˜ SEG0 , respectively. The sensing pins BN0~BN3 are respectively electrically connected to the input pins COM0~COM3.

In other embodiments, the capacitive touch device 520 may have more or less sensing areas and sensing pins. The present invention does not limit the type of the capacitive touch device 520 . In a possible embodiment, the capacitive touch device 520 is a touch keyboard or a touch pad. In other embodiments, the capacitive touch device 520 may cover the display device 510 .

The control circuit 530 has input and output pins IOA0-IOA3 and IOB0-IOB3. The input and output pins IOA0~IOA3 are electrically connected to the input pins SEG0~SEG3 and the sensing pins AN3~AN0. The input and output pins IOB0~IOB3 are electrically connected to the input pins COM0~COM3 and the sensing pins BN0~BN3. In this embodiment, since the display device 510 and the capacitive touch device 520 share the input and output pins IOA0 - IOA3 and IOB0 - IOB3 , the number of the input and output pins of the control circuit 530 can be reduced.

During a display period, the control circuit 530 provides segment signals to the input pins SEG0-SEG3 through the input and output pins IOA0-IOA3, and provides a common signal to the input pins COM0-COM3 through the input and output pins IOB0-IOB3. At this time, the display device 510 presents a screen according to the potentials of the input pins SEG0 - SEG3 and COM0 - COM3 .

During a first sensing period, the control circuit 530 scans the voltage levels of the input and output pins IOA0-IOA3 and a part of the pins IOB0-IOB3 to determine whether the capacitive touch device 520 is touched. At this time, the scanned input and output pins constitute a first pin group. When the control circuit 530 scans the first pin group, the control circuit 530 may set the voltage levels of the input and output pins IOA0-IOA3 and another part of the pins of IOB0-IOB3 to be equal to a first predetermined level. In this example, the input and output pins set by the control circuit 530 constitute a second pin group. In other embodiments, the control circuit 530 may set the impedance of each pin of the second pin group to a high impedance state (High Impedance). During the first sensing period, after the control circuit 530 scans the voltage levels of all the pins of the first pin group, the control circuit 530 may scan the voltage levels of all the pins of the second pin group. When the control circuit 530 scans the second pin group, the control circuit 530 sets the voltage levels of all the pins of the first pin group to be equal to a second preset level, or sets the voltage levels of the first pin group The impedance of each pin is in a high impedance state.

In other embodiments, the control circuit 530 scans the voltage levels of all the pins of the second pin group during the second sensing period. In this example, the control circuit 530 sets the voltage level of each pin of the first pin group equal to a second predetermined level, or sets the impedance of each pin of the first pin group to be A high impedance state.

In a possible embodiment, the input and output pins IOA0 - IOA3 transmit the same kind of signals. Therefore, the control circuit 530 uses the input and output pins IOA0 to IOA3 as a first pin group. In addition, since the input and output pins IOB0 ˜ IOB3 transmit the same type of signals, the control circuit 530 uses the input and output pins IOB0 ˜ IOB3 as a second pin group.

FIG. 5B is another schematic diagram of the operating system of the present invention. Figure 5B is similar to Figure 5A, except that Figure 5B has additional resistors R1 to R8. The resistors R1 ˜ R4 are respectively coupled between the input/output pins IOA0 ˜IOA3 and the input pins SEG0 ˜SEG3 . The resistors R5 ˜ R8 are respectively coupled between the input and output pins IOB0 ˜ IOB3 and the input pins COM0 ˜ COM3 . Taking the resistors R1 and R5 as examples, the resistor R1 is coupled between the input/output pin IOA0 and the input pin SEG0, and the resistor R5 is coupled between the input/output pin IOB0 and the input pin COM0. In a possible embodiment, the impedances of the resistors R1 ˜ R8 are about 1KΩ˜10KΩ.

In some embodiments, the display device 510 is a liquid crystal display device. Resistors R1~R8 are used to increase the accuracy of the sensing operation. In this example, the control circuit 530 performs a sensing operation for detecting the touched area of the capacitive touch device 520 .

6A to 6D are schematic diagrams of voltage level changes of the first and second pin groups of the present invention. It is assumed that the input and output pins IOA0-IOA3 belong to the first pin group, and the input and output pins IOB0-IOB3 belong to the second pin group. Since the characteristics of the input and output pins IOA0~IOA3 are the same, Figures 6A~6D only show the level changes of the input and output pins IOA0. In addition, since the characteristics of the input and output pins IOB0~IOB3 are the same, Figures 6A~6D only show the level change of the input and output pins IOB0.

In FIG. 6A, during the display period 611, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level L1, and sets the voltage level of the input/output pin IOB0 to the level L3. At this time, the display device 510 presents a picture according to the voltage levels of the input and output pins IOA0 and IOB0. During the sensing period 612, the control circuit 530 sets the voltage level of the input and output pins IOA0 (the first pin group) to a floating level. In a possible embodiment, the control circuit 530 does not provide any voltage to the input and output pins IOA0. In this example, the impedance of the I/O pin IOA0 is in a high impedance state. Therefore, the input/output pin IOA0 is a floating level. During the sensing period 612, the control circuit 530 detects the level of the input and output pins IOB0 (the second pin group). In a possible embodiment, the control circuit 530 first provides a reference voltage to the input/output pin IOB0, and then determines whether the voltage of the input/output pin IOB0 changes. If so, it means that the sensing area corresponding to the input/output pin IOB0 is touched. In some embodiments, during the sensing period 612, the control circuit 530 sequentially detects the levels of the input and output pins IOB0-IOB3 (the second pin group). During the display period 613, the control circuit 530 again sets the voltage level of the input/output pin IOA0 to the level L1, and sets the voltage level of the input/output pin IOB0 to the level L3. Therefore, the display device 510 presents the corresponding screen.

During the display period 614, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level L2, and sets the voltage level of the input/output pin IOB0 to the level L4. During the sensing period 615, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the floating level. At this time, the control circuit 530 detects the voltage levels of the input and output pins IOB0 ˜ IOB3 . During the display period 616, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level L2, and sets the voltage level of the input/output pin IOB0 to the level L4.

During the display period 617, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level L2, and sets the voltage level of the input/output pin IOB0 to the level L4. During the sensing period 618, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the floating level. At this time, the control circuit 530 scans the voltage levels of the input and output pins IOB0 ˜ IOB3 . During the display period 619, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level L2, and sets the voltage level of the input/output pin IOB0 to the level L4.

In FIG. 6B, during the display period 621, the control circuit 530 sets the voltage level of the input/output pin IOB0 to level L5, and sets the voltage level of the input/output pin IOA0 to level L7. Therefore, the display device 510 presents a corresponding screen according to the voltage levels of the input and output pins IOA0 and IOB0. During the sensing period 622, the control circuit 530 sets the voltage level of the input/output pin IOB0 to a floating level, and sequentially scans the voltage levels of the input/output pins IOA0-IOA3. During the display period 623, the control circuit 530 again sets the voltage level of the input/output pin IOB0 to the level L5, and sets the voltage level of the input/output pin IOA0 to the level L7. Therefore, the display device 510 presents a corresponding screen according to the voltage levels of the input and output pins IOA0 and IOB0.

During the display period 624, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level L6, and sets the voltage level of the input/output pin IOA0 to the level L8. During the sensing period 625, the control circuit 530 sets the voltage level of the input and output pins IOB0 to the floating level, and scans the voltage levels of the input and output pins IOA0-IOA3. During the display period 626, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level L6, and sets the voltage level of the input/output pin IOA0 to the level L8.

During the display period 627, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level L6, and sets the voltage level of the input/output pin IOA0 to the level L7. During the sensing period 628, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the floating level. At this time, the control circuit 530 scans the levels of the input and output pins IOA0-IOA3. During the display period 629, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level L6, and sets the voltage level of the input/output pin IOA0 to the level L7.

In FIG. 6C, during the display period 631, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level VDD, and sets the voltage level of the input/output pin IOB0 to the level GND. Therefore, the display device 510 presents a corresponding screen according to the voltages of the input and output pins IOA0 and IOB0. During the sensing period 632, the control circuit 530 sets the voltage level of the input and output pins IOA0 to be the level GND (or a first predetermined level), and scans the voltage levels of the input and output pins IOB0-IOB3. During the display period 633, the control circuit 530 again sets the voltage level of the input/output pin IOA0 to the level VDD, and sets the voltage level of the input/output pin IOB0 to the level GND. Therefore, the display device 510 presents a corresponding screen according to the voltages of the input and output pins IOA0 and IOB0.

During the display period 634, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level GND, and sets the voltage level of the input/output pin IOB0 to the level VDD. During the sensing period 635, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level GND. At this time, the control circuit 530 scans the voltage levels of the input and output pins IOB0 ˜ IOB3 . During the display period 636, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level GND, and sets the voltage level of the input/output pin IOB0 to the level VDD.

During the display period 637, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level GND, and sets the voltage level of the input/output pin IOB0 to the level VDD. During the sensing period 638, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level GND. At this time, the control circuit 530 scans the voltage levels of the input and output pins IOB0 ˜ IOB3 . During the display period 639, the control circuit 530 sets the voltage level of the input/output pin IOA0 to the level GND, and sets the voltage level of the input/output pin IOB0 to the level VDD.

In FIG. 6D, during the display period 641, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level GND, and sets the voltage level of the input/output pin IOA0 to the level VDD. Therefore, the display device 510 presents a corresponding screen according to the voltages of the input and output pins IOA0 and IOB0. During the sensing period 642, the control circuit 530 sets the voltage level of the input and output pins IOB0 to the level VDD (or a second predetermined level), and scans the voltage levels of the input and output pins IOA0-IOA3. During the display period 643, the control circuit 530 again sets the voltage level of the input/output pin IOB0 to the level GND, and sets the voltage level of the input/output pin IOA0 to the level VDD.

During the display period 644, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level VDD, and sets the voltage level of the input/output pin IOA0 to the level GND. During the sensing period 645, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level VDD. At this time, the control circuit 530 scans the voltage levels of the input and output pins IOA0-IOA3. During the display period 646, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level VDD, and sets the voltage level of the input/output pin IOA0 to the level GND.

During the display period 647, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level VDD, and sets the voltage level of the input/output pin IOA0 to the level GND. During the sensing period 648, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level VDD. At this time, the control circuit 530 scans the voltage levels of the input and output pins IOA0-IOA3. During the display period 649, the control circuit 530 sets the voltage level of the input/output pin IOB0 to the level VDD, and sets the voltage level of the input/output pin IOA0 to the level GND.

FIG. 7 is a schematic diagram of a sensing operation performed by the control circuit 530 of the present invention. First, each pin of the first pin group is set equal to a first preset level (step S711 ). Then, the voltage level of each pin of the second pin group is scanned (step S712). Next, it is determined whether all the pins of the second pin group have been scanned (step S713). If the scan has not been completed, go back to step S712. If all pins of the second pin group are scanned, step S714 is executed. Step S714 sets each pin of the second pin group equal to a second preset level. Then, the voltage level of each pin of the first pin group is scanned (step S715). Next, it is determined whether the voltage levels of all the pins of the first pin group have been scanned (step S716 ). If the scan has not been completed, go back to step S715. If the voltage levels of all the pins of the first pin group are scanned, the sensing operation ends.

In a possible embodiment, the second preset level in step S714 is relative to the first preset level in step S711. For example, when the first predetermined level is a high level, the second predetermined level is a low level. When the first preset level is a low level, the second preset level is a high level. In some embodiments, the first preset level in step S711 and the second preset level in step S714 are both equal to a floating level. For example, step S711 may not provide any voltage to the first pin group, and step S714 may not provide any voltage to the second pin group.

In other embodiments, steps S714 to S716 are performed earlier than step S711. In this example, the control circuit 530 first sets the voltage level of each pin of the second pin group equal to the second predetermined level, and then scans the voltage level of the pins of the first pin group, After scanning the voltage levels of all the pins of the first pin group, set the voltage level of each pin of the first pin group to be equal to the first preset level, and scan the second pin The voltage level of each pin of the group.

FIG. 8A is a possible schematic diagram of the display area of the present invention. In this embodiment, the display area 800A includes a plurality of light emitting diodes (LEDs). Each light-emitting diode is coupled to one of the input pins SEG0 ˜ SEG3 and one of the input pins COM0 ˜ COM3 . Taking the light emitting diode 810 as an example, the anode of the light emitting diode 810 is coupled to the input pin SEG0, and the cathode of the light emitting diode 810 is coupled to the input pin COM0. In this example, when the voltage difference between the input pins SEG0 and COM0 is greater than the turn-on voltage of the light-emitting diode 810, the light-emitting diode 810 is turned on. When the voltage difference between the input pins SEG0 and COM0 is not greater than the turn-on voltage of the light-emitting diode 810 , the light-emitting diode 810 is not lit.

During the sensing period, since the input pins COM0~COM3 may be equal to a high level (or called the second preset level), even if the input pins SEG0~SEG3 receive a small voltage, the light-emitting diode 810 will not be turned on . In addition, since the input pins SEG0 ˜ SEG3 may be equal to a low level (or referred to as the first preset level), even if the input pins COM0 ˜ COM3 receive a small voltage, the light emitting diode 810 will not be turned on. Therefore, during the sensing period, when the control circuit 530 performs a sensing operation on the capacitive touch device 520, the display device 510 will not be disturbed by the sensing operation.

FIG. 8B is another possible schematic diagram of the display area of the present invention. In this embodiment, the display area 800B includes a plurality of liquid crystal capacitors. Each liquid crystal capacitor is coupled to one of the input pins SEG0 ˜ SEG3 and one of the input pins COM0 ˜ COM3 . Taking the liquid crystal capacitor 820 as an example, the liquid crystal capacitor 820 is coupled between the input pins SEG0 and COM0.

During the sensing period, since the voltage levels of the input pins COM0 ˜ COM3 may be equal to the floating level, even if the input pins SEG0 ˜ SEG3 receive a small voltage, the capacitor 820 will not be charged. In addition, since the voltage level of the input pins SEG0 ˜ SEG3 may be equal to a floating level, even if the input pins COM0 ˜ COM3 receive a small voltage, the capacitor 820 will not be charged. Therefore, during the sensing period, when the control capacitor 530 performs a sensing operation on the capacitive touch device 520 , the sensing operation does not interfere with the display device 510 .

FIG. 9 is a possible schematic diagram of the control circuit of the present invention. As shown in the figure, the control circuit 900 includes a display controller 910 , a sensing circuit 920 and a transmission circuit 930 . The display controller 910 is used for providing driving signals SSG0, SCM0 and a switching signal SEL. In a possible embodiment, the driving signal SSG0 is a segment signal, and the driving signal SCM0 is a common signal. In other embodiments, the display controller 910 integrates the image driver 131 and the microcontroller circuit 132 of FIG. 1 . In this example, the driving signal SSG0 is used as one of the driving signals SD1 ˜ SD4 , and the driving signal SCM0 is used as the other one of the driving signals SD1 ˜ SD4 .

The sensing circuit 920 provides the reference voltage DK and receives the sensing voltages V _AN3 and V _BN0 . In a possible embodiment, the sensing voltage V _AN3 is the voltage of the sensing pin AN3 of the capacitive touch device 520 , and the sensing voltage V _BN0 is the voltage of the sensing pin BN0 of the capacitive touch device 520 . . In other embodiments, the sensing circuit 920 receives less or more sensing voltages, such as the voltages of the sensing pins AN0 ˜ AN2 and BN1 ˜ BN3 of the capacitive touch device 520 . Since the characteristics of the sensing circuit 920 are similar to the characteristics of the sensing circuit 133 in FIG. 1 , details are not described herein again.

The transmission circuit 930 selects the display controller 910 or the sensing circuit 920 according to the switching signal SEL, so as to provide the output of the display controller 910 or the sensing circuit 920 to the input and output pins IOA0 and IOB0. During a display period, the transmission circuit 930 provides the driving signals SSG0 and SCM0 to the input and output pins IOA0 and IOB0 according to the switching signal SEL. During a sensing period, the transmission circuit 930 provides the reference voltage DK to one of the input and output pins IOA0 and IOB0 according to the switching signal SEL, and sets the level of the other of the input and output pins IOA0 and IOB0.

It is assumed that the input/output pin IOA0 belongs to the first pin group, and the input/output pin IOB0 belongs to the second pin group. During a first sensing period, the display controller 910 requests the transmission circuit 930 to provide the reference voltage DK to the input/output pin IOA0, and to provide the driving signal SCM0 to the input/output pin IOB0. At this time, the driving signal SCM0 is equal to a first predetermined level. In other embodiments, the display controller 910 may request the transmission circuit 930 to stop transmitting any signal to the input/output pin IOB0. In this example, the voltage level of the input/output pin IOB0 is a floating level. In some embodiments, when the transmission circuit 930 provides the reference voltage DK to the input/output pin IOA0, the sensing circuit 920 provides a first predetermined level (eg, a low level or a high level). In this example, the transmission circuit 930 may transmit the first preset bit provided by the sensing circuit 920 to the input/output pin IOB0.

During the second sensing period, the display controller 910 requests the transmission circuit 930 to provide the reference voltage DK to the input/output pin IOB0, and to provide the driving signal SSG0 to the input/output pin IOA0. At this time, the driving signal SSG0 is equal to a second predetermined level. In other embodiments, the display controller 910 may request the transmission circuit 930 to stop transmitting any signal to the input/output pin IOA0. In this example, the voltage level of the input/output pin IOA0 is a floating level. In some embodiments, when the transmission circuit 930 provides the reference voltage DK to the input/output pin IOB0, the sensing circuit 920 provides a second predetermined level (eg, a high level or a low level). In this example, the transmission circuit 930 may transmit the second preset bit grant provided by the sensing circuit 920 to the input/output pin IOA0.

After the transmission circuit 930 provides the reference voltage DK to the I/O pin IOA0, the sensing circuit 920 detects the voltage V _AN3 of the I/O pin IOA0. In this example, when the voltage V _AN3 of the input/output pin IOA0 is not equal to the reference voltage DK, it means that the sensing area corresponding to the sensing pin AN3 of the capacitive touch device 520 is touched. Therefore, the sensing circuit 920 informs the display controller 910 so that the display controller 910 performs a corresponding action.

Similarly, after the transmission circuit 930 provides the reference voltage DK to the input and output pin IOB0, the sensing circuit 920 detects the voltage V _BN0 of the input and output pin IOB0. In this example, when the voltage V _BN0 of the input/output pin IOB0 is not equal to the reference voltage DK, it means that the sensing area corresponding to the sensing pin BN0 of the capacitive touch device 520 is touched. Therefore, the sensing circuit 920 informs the display controller 910, so that the display controller 910 performs another corresponding action.

Before detecting the voltage of the input and output pins IOA0 or IOB0, the sensing circuit 920 first provides the reference voltage DK to the input and output pins IOA0 or IOB0. Therefore, the sensing operation performed by the sensing circuit 920 is not easily disturbed by noise.

For the convenience of description, FIG. 9 only shows the input and output pins IOA0 and IOB0, but is not intended to limit the present invention. In other embodiments, the transmission circuit 930 is coupled to more input and output pins (eg, IOA1 ˜IOA3 , IOB1 ˜IOB3 ). The present invention does not limit the structure of the transmission circuit 930 . In a possible embodiment, the transmission circuit 930 includes switching circuits 931 and 932 . The switching circuits 931 and 932 transmit corresponding signals according to the switching signal SEL. In other embodiments, the display controller 910 provides two switching signals for controlling the switching circuits 931 and 932 .

In other embodiments, before the sensing circuit 920 performs a sensing operation to determine whether the capacitive touch device 520 is touched, the sensing circuit 920 may send a request signal (not shown) to the display controller 910 . The display controller 910 responds to the sensing circuit 920 and sends out an approval signal. During a specific period, the sensing circuit 920 can control the voltage levels of the input and output pins IOA0 and IOB0. After a certain period, the display controller 910 controls the voltage levels of the input and output pins IOA0 and IOB0.

During the sensing period, the control circuit 900 scans a part of the input and output pins, and sets another part of the input and output pins to a preset level (eg, a low level or a high level) or a floating level. Therefore, the display device 510 is not affected by the sensing operation of the control circuit 900 during the sensing period.

Furthermore, when the display device 510 may be a passive matrix display, since the response rate of the passive matrix display is relatively slow, even if the potential of the input and output pins changes, the passive matrix display does not respond immediately. Therefore, even if the input and output pins are set equal to a reference voltage, the display device 510 will not be disturbed by the reference voltage. In other embodiments, even if the display device 510 is an active matrix display, since the reference voltage is lower than the level of the driving signal, the display device 510 will not be affected by the reference voltage. In some embodiments, the sensing period is shorter than the display period, so that the display device 510 is not affected by the sensing operation.

Unless otherwise defined, all terms (including technical and scientific terms) herein are commonly understood by those of ordinary skill in the art to which this invention belongs. Furthermore, unless expressly stated otherwise, the definitions of words in general dictionaries should be construed as consistent with their meanings in articles in the related technical field, and should not be construed as ideal states or overly formal voices.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. . For example, the system, apparatus or method according to the embodiments of the present invention may be implemented in a physical embodiment of hardware, software, or a combination of hardware and software. Therefore, the protection scope of the present invention should be determined by the scope of the appended patent application.

100, 500: Operating system

110, 510: Display device

111, 511, 800A, 800B: Display area

120, 520: Capacitive touch device

121~124, 521~528: Area

125~128: Sensing element

130, 530, 900: Control circuit

131: Video driver

132: Microcontroller circuit

133, 920: Sensing circuit

134, 930: Transmission circuit

135~138, IOA0~IOA3, IOB0~IOB3: Input and output pins

PN ₁ ~PN ₈ , SEG0~SEG3, COM0~COM3, AN0~AN3, BN0~BN3: Pin

SD1~SD4, SSG0, SCM0: drive signal

V _PN5 ~V _PN8 , V _AN3 , V _BN0 : Voltage

SEL: switch signal

SW1, SW2, 931, 932: switching circuit

PA1~PA8: Path

310~340: Sensing unit

Cmp, Cmn, 820: Capacitor

313: Comparator

314: Controller

DK: reference voltage

311, 312: Node

SCM: Compare Signal

Sap, SAn: adjust the signal

P ₁₁ ~P ₄₄ : Pixels

ST ₁ ~ST ₄ : On signal

R1~R8: Resistor

611, 613, 614, 616, 617, 619, 621, 623, 624, 626, 627, 629, 631, 633, 634, 636, 637, 639, 641, 643, 644, 646, 647, 649: Display period

612, 615, 618, 622, 625, 628, 632, 635, 638, 642, 645, 648: Sensing period

L1~L8, VDD, GND: level

S711~S716: Steps

810: Light Emitting Diode

910: Display Controller

FIG. 1 is a schematic diagram of the operating system of the present invention. FIG. 2 is a possible schematic diagram of the transmission circuit of the present invention. FIG. 3 is a possible schematic diagram of the sensing circuit of the present invention. FIG. 4 is a possible schematic diagram of the display device of the present invention. FIG. 5A is another schematic diagram of the operating system of the present invention. FIG. 5B is another schematic diagram of the operating system of the present invention. 6A to 6D are schematic diagrams of voltage changes of the first and second pin groups of the present invention. FIG. 7 is a schematic flowchart of a sensing operation performed by the control circuit of the present invention. FIG. 8A is a schematic diagram of the display area of the present invention. FIG. 8B is another schematic diagram of the display area of the present invention. FIG. 9 is another schematic diagram of the control circuit of the present invention.

500: Operating System

510: Display device

520: Capacitive Touch Device

530: Control circuit

511: Display area

SEG0~SEG3, COM0~COM3: Input pins

521~528: Sensing area

AN0~AN3, BN0~BN3: Sensing pins

IOA0~IOA3, IOB0~IOB3: Input and output pins

Claims (9)

A control circuit includes: a first input and output pin for coupling to a first input pin of a display device and a first sensing pin of a capacitive touch device; a second input and output pin pin for coupling to a second input pin of the display device and a second sensing pin of the capacitive touch device; a sensing circuit based on the first input and output pin and the second input The voltage of the output pin is used to determine whether the capacitive touch device is touched; and a display controller provides a first driving signal to the display device through the first input and output pin during a display period, and A second driving signal is provided to the display device through the second input/output pin; wherein: in a first sensing period, the first input/output pin is equal to a first preset level, and the sensing The circuit detects the voltage of the second input and output pins. During the first sensing period, the sensing circuit sets the first input and output pins to be equal to the first preset level. The control circuit of claim 1, wherein in a second sensing period, the sensing circuit sets the second input/output pin to be equal to a second preset level, and detects the voltage of the first input/output pin . The control circuit of claim 2, wherein the first predetermined level is relative to the second predetermined level. The control circuit of claim 2, wherein the first preset level and the second preset level are both equal to a floating level. The control circuit of claim 1, wherein the sensing circuit comprises: A comparator has a non-inverting input terminal, an inverting input terminal and an output terminal, wherein the inverting input terminal is coupled to the first input and output pin; a first capacitor is coupled to a specific node and between the non-inverting input terminal; a second capacitor coupled between the specific node and the inverting input terminal; and a controller for controlling the voltage of the specific node, and according to the non-inverting input terminal and the inverting input terminal The voltage of the phase input terminal adjusts the capacitance of the second capacitor. A display device, comprising: a display device having a first input pin and a second input pin; a capacitive touch device having a first sensing pin and a second sensing pin; and A control circuit includes: a first input/output pin coupled to the first input pin and the first sensing pin; a second input/output pin coupled to the second input pin and the first sensing pin Two sensing pins; a sensing circuit, according to the voltages of the first and second input and output pins, to determine whether the capacitive touch device is touched; and a display controller, for a display period, through the The first input and output pins provide a first driving signal to the display device, and through the second input and output pins, provide a second driving signal to the display device; wherein: during a first sensing period, the The sensing circuit sets the first input/output pin to be equal to a first preset level, and detects the voltage of the second input/output pin. The display device of claim 6, wherein the display device is a passive matrix display. The display device of claim 6, wherein during the first sensing period, the sensing The detection circuit first provides a reference voltage to the second input/output pin, and then detects the voltage of the second input/output pin, and the reference voltage is one third or one fourth of the first driving signal. A control circuit includes: a first input and output pin for coupling to a first input pin of a display device and a first sensing pin of a capacitive touch device; a second input and output pin pin for coupling to a second input pin of the display device and a second sensing pin of the capacitive touch device; a sensing circuit based on the first input and output pin and the second input The voltage of the output pin is used to determine whether the capacitive touch device is touched; and a display controller provides a first driving signal to the display device through the first input and output pin during a display period, and A second driving signal is provided to the display device through the second input/output pin; wherein: in a first sensing period, the first input/output pin is equal to a first preset level, and the sensing The circuit detects the voltage of the second input and output pins. During the first sensing period, the display controller sets the first input and output pins to be equal to the first preset level.

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