Control circuit and display device

Abstract

The present application provides a control circuit and a display device. The control circuit includes a first input / output pin, a second input / output pin, a sensing circuit and a display controller. The first and second input / output pins are coupled to a display device and a capacitive touch device. The sensing circuit determines whether the capacitive touch device is touched according to voltages of the first and second input / output pins. During a first display period, the display controller provides a first driving signal to the display device through the first input / output pin and provides a second driving signal to the display device through the second input / output pin. From an end time point of the first display period to a start time point of a second display period, the sensing circuit detects the voltage of the first input / output pin and stops detecting the voltage of the second input / output pin.

Description

Technical Field

[0001] The present invention relates to a control circuit and a display device, and more particularly to a control circuit coupled to a display device and a touch device, and a display device including the control circuit. Background Art

[0002] With the advancement of technology, the types and functions of electronic devices are increasing. Most electronic devices have an input device and an output device. A control device within the electronic device controls the operation of the electronic device based on 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, because touch devices and display devices each have a large number of pins, the number of pins of the control device must be greater than the total number of pins of the touch device and display device in order to couple the touch device and display device. As a result, the available space inside the electronic device is reduced. Summary of the Invention

[0003] The present invention provides a control circuit, comprising a first input / output pin, a second input / output pin, a sensing circuit, and a display controller. The first input / output pin is used to couple a first input pin of a display device and a first sensing pin of a capacitive touch device. The second input / output pin is used to couple 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 based on the voltages of the first input / output pin and the second input / output pin. During a first display period and a second display period, the display controller provides a first drive signal to the display device via the first input / output pin, and provides a second drive signal to the display device via the second input / output pin. After an end time point of the first display period, the display controller stops providing the first drive signal and the second drive signal. After a start time point of the second display period, the display controller provides the first drive signal and the second drive signal. From the end time point of the first display period to the start time point of the second display period, the sensing circuit detects the voltage of the first input / output pin and stops detecting the voltage of the second input / output pin.

[0004] The present invention further provides a display device comprising 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 comprises a first input / output pin, a second input / output pin, a sensing circuit, and a display controller. The first input / output pin is coupled to the first input pin and the first sensing pin. The second input / output pin is coupled to the second input pin and the second sensing pin. The sensing circuit determines whether the capacitive touch device is touched based on the voltages at the first input / output pin and the second input / output pin. During a first display period and a second display period, the display controller provides a first drive signal to the display device via the first input / output pin, and provides a second drive signal to the display device via the second input / output pin. During the first display period and the second display period, the display device presents an image based on the first drive signal and the second drive signal. After an end point in the first display period, the display controller stops providing the first drive signal and the second drive signal. After the start of the second display period, the display controller provides the first and second drive signals. From the end of the first display period until the start of the second display period, the sensing circuit detects the voltage of the first input / output pin and stops detecting the voltage of the second input / output pin. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0006] Figure 1 Schematic diagram of the operating system of the present invention.

[0007] Figure 2 FIG. 4 is a possible schematic diagram of a transmission circuit of the present invention.

[0008] Figure 3 FIG. 4 is a possible schematic diagram of the sensing circuit of the present invention.

[0009] Figure 4 FIG. 1 is a possible schematic diagram of a display device of the present invention.

[0010] Figures 5A to 5C FIG. 1 is a schematic diagram of voltage level changes of input and output pins of the present invention.

[0011] Figure 6A FIG. 4 is another schematic diagram of the operating system of the present invention.

[0012] Figure 6B FIG. 4 is another schematic diagram of the operating system of the present invention.

[0013] Figures 7A to 7C FIG. 4 is a schematic diagram of voltage level changes of the first pin group and the second pin group of the present invention.

[0014] Figure 8 2 is a flow chart of the sensing operation of the control circuit of the present invention.

[0015] Figure 9A FIG. 4 is a possible schematic diagram of the display area of ​​the present invention.

[0016] Figure 9B FIG. 4 is another possible schematic diagram of the display area of ​​the present invention.

[0017] Figure 10 FIG. 2 is another possible schematic diagram of the control circuit of the present invention.

[0018] Figure Number:

[0019] 100, 600: operating system

[0020] 110, 610: Display device

[0021] 111, 611: Display area

[0022] 120, 620: Capacitive touch device

[0023] 121-124, 621-628, 900A, 900B: Area

[0024] 125-128: Sensing element

[0025] 130, 630, 1000: Control circuit

[0026] 131: Image Driver

[0027] 132: Microcontroller Circuit

[0028] 133, 1020: Sensing circuit

[0029] 134, 1030: Transmission circuit

[0030] 135-138, IOA0-IOA3, IOB0-IOB3: Input / output pins PN1-PN8, SEG0-SEG3, COM0-COM3, AN0-AN3, BN0-BN3: Pins SD1-SD4: Drive signals

[0031] V PN5 ~V PN8 、V 135 ~V138 、V IOB0 、V IOA0 ~V IOA2 、V AN3 、V BN3 : Voltage SEL: Switching signal

[0032] SW1, SW2, 1031, 1032: switching circuit PA1~PA8: path

[0033] 310-340: Sensing unit

[0034] Cmp, Cmn: capacitance

[0035] 313: Comparator

[0036] 314: Controller

[0037] DK: reference voltage

[0038] 311, 312: Node

[0039] SCM: Comparison signal

[0040] Sap, San: Adjust the signal

[0041] P 11 ~P 44 :pixel

[0042] ST1~ST4: Open signal

[0043] 511-518, 531-542, 561-572, 711-716, 731-742, 761-772: Display period

[0044] 521-524, 551-556, 581-586, 721-723, 751-756, 781-786: Sensing period

[0045] L0~L2、LH、LM:Level

[0046] TP1~TP62: Time points

[0047] P1~P8: Period

[0048] R1~R8:resistance

[0049] S811~S816:Steps DETAILED DESCRIPTION

[0050] To make the objectives, features, and advantages of the present invention more readily apparent, the following examples are presented and described in detail with reference to the accompanying drawings. This specification provides various examples to illustrate the technical features of various embodiments of the present invention. The configurations of the various components in the examples are for illustrative purposes only and are not intended to limit the present invention. Furthermore, some duplication of figure numerals in the examples is for simplification and does not imply a correlation between the different examples.

[0051] Figure 1 Schematic diagram of the operating system of the present invention. Figure 1 As shown, 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 PN1 to PN4 and a display area 111. The display area 111 displays images according to the voltage levels of pins PN1 to PN4. The present invention does not limit the number of pins of the display device 110. In other embodiments, the display device 110 may have more or fewer pins. In addition, the present invention does not limit the type of display device 110. In one possible embodiment, the display device 110 is a super twisted liquid crystal display panel (STN LCD panel).

[0052] The capacitive touch device 120 includes regions 121-124, sensing elements 125-128, and pins PN5-PN8, but this is 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 is not limited to the type of capacitive touch device 120. In one embodiment, the capacitive touch device 120 is a touch keyboard or a touch pad.

[0053] In this embodiment, the sensing element 125 is arranged in the area 121 to sense whether the area 121 is touched, the sensing element 126 is arranged in the area 122 to sense whether the area 122 is touched, the sensing element 127 is arranged in the area 123 to sense whether the area 123 is touched, and the sensing element 128 is arranged in the area 124 to sense whether the area 124 is touched. In one possible embodiment, the sensing elements 125 to 128 are capacitive sensing elements. Pin PN5 outputs the sensing result of the sensing element 125. Pin PN6 outputs the sensing result of the sensing element 126. Pin PN7 outputs the sensing result of the sensing element 127. Pin PN8 outputs the sensing result of the sensing element 128. Taking the sensing element 125 as an example, when the area 121 is not touched, the capacitance of the sensing element 125 remains unchanged. Therefore, the voltage V of the pin PN5 PN5 However, when the area 121 is touched, the capacitance of the sensing element 125 will change (may become larger), so the voltage V PN5 Less than the reference voltage.

[0054] The control circuit 130 includes an image driver 131, a microcontroller circuit 132, a sensing circuit 133, a transmission circuit 134, and input-output pins 135 to 138. The image driver 131 is used to drive the display device 110. In this embodiment, the image driver 131 generates drive signals SD1 to SD4, but this is not intended to limit the present invention. In other embodiments, the image driver 131 may generate more or fewer drive signals. The present invention does not limit the circuit architecture of the image driver 131. In one possible embodiment, the image driver 131 is a liquid crystal driver. In another possible embodiment, the image driver 131 is a COM / SEG driver for generating COM / SEG waveforms.

[0055] 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 one possible embodiment, the sensing circuit 133 first provides a reference voltage DK to the pins PN5 to PN8 of the capacitive touch device 120, and then detects whether the voltage levels of the pins PN5 to PN8 change. When the voltage levels of the pins PN5 to PN8 change, it indicates that the corresponding area is touched. For example, when the voltage V PN5 When the voltage V of the pin PN5 is not equal to the reference voltage DK, it indicates that the area 121 corresponding to the pin PN5 is touched.PN5 When the voltage is equal to the reference voltage DK, it indicates that the region 121 corresponding to the pin PN5 is not touched. In some embodiments, the reference voltage DK is less than 1 volt.

[0056] The transmission circuit 134 includes a switching circuit SW1 and a switching circuit SW2. The switching circuit SW1 is coupled between the image driver 131 and the input / 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 / output pins 135-138. In this state, the input / output pins 135-138 function as output pins, outputting the driving signals SD1-SD4 to the display device 110.

[0057] The switching circuit SW2 is coupled between the sensing circuit 133 and the input / 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 / output pins 135-138 and then transmit the voltage V PN5 ~V PN8 to the sensing circuit 133 .

[0058] In this embodiment, the input and output pins 135-138 are used to transmit analog signals. In other words, the driving signals SD1-SD4 and the voltage V PN5 ~V PN8 All are analog signals. Furthermore, in this embodiment, the display device 110 and the capacitive touch device 120 share input and output pins 135-138, thereby reducing the number of input and output pins of the control circuit 130. In other embodiments, the display device 110 and the capacitive touch device 120 may share more or fewer input and output pins.

[0059] Since the characteristics of I / O pins 135-138 are the same, the following description uses I / O pin 135 as an example. As shown, I / O pin 135 is coupled to pin PN1 of display device 110 and pin PN5 of capacitive touch device 120. When switching circuit SW1 is on, I / O pin 135 transmits drive signal SD1. When switching circuit SW2 is on, I / O pin 135 transmits reference voltage DK and voltage V on pin PN5 of capacitive touch device 120. PN5 .

[0060] In one embodiment, the voltages V at the pins PN5 to PN8 are PN5 ~V PN8Therefore, even if the pins PN5 to PN8 are coupled to the pins PN1 to PN4, the voltage V PN5 ~V PN8 It also does not affect the image displayed by the display device 110 .

[0061] For example, assume that the maximum voltage of the driving signals SD1-SD4 is 4V. In this example, the voltage V PN5 ~V PN8 The maximum voltage of is about 1.3V (ie, one-third of the voltage of the driving signals SD1-SD4) or 1V (ie, one-quarter of the voltage of the driving signal SD1). PN5 ~V PN8 is very small, so the voltage V PN5 ~V PN8 It will not affect the image displayed by the display device 110. In other embodiments, the voltage V PN5 ~V PN8 Less than 1V.

[0062] The micro-control circuit 132 generates a switching signal SEL to control the switching circuits SW1 and SW2. In this embodiment, the switching circuits SW1 and SW2 are not simultaneously turned on. For example, when the micro-control circuit 132 turns on the switching circuit SW1, the micro-control circuit 132 turns off 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.

[0063] The present invention is not limited to the circuit architecture of the microcontroller 132. In one embodiment, the microcontroller 132 is a microcontroller (MCU). In this embodiment, the microcontroller 132 uses a single switching signal (e.g., SEL) to control the switching circuits SW1 and SW2, but this is not intended to limit the present invention. In other embodiments, the microcontroller 132 uses two switching signals to control the switching circuits SW1 and SW2, respectively.

[0064] In other embodiments, the microcontroller 132 further triggers the graphics driver 131 and the sensing circuit 133. When the graphics driver 131 is triggered, it generates driving signals SD1-SD4. At this point, the microcontroller 132 activates the switching circuit SW1 and deactivates the switching circuit SW2 via the switching signal SEL. Consequently, the input / output pins 135-138 output the driving signals SD1-SD4 to the display device 110. The display device 110 displays images based on the driving signals SD1-SD4.

[0065] When the microcontroller 132 triggers the sensing circuit 133, the sensing circuit 133 generates a reference voltage DK. At this time, the microcontroller 132 turns on the switching circuit SW2 and turns off 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 voltage V PN5 ~V PN8 To the sensing circuit 133. In this example, the sensing circuit 133 is based on the voltage V PN5 ~V PN8 , determine whether areas 121 to 124 are touched.

[0066] In other embodiments, when the micro-control circuit 132 triggers the sensing circuit 133, the micro-control circuit 132 may instruct the graphics driver 131 to suspend generating the driving signals SD1-SD4. In some embodiments, the graphics driver 131 may continue to generate the driving signals SD1-SD4, but because the micro-control circuit 132 does not turn on the switching circuit SW1, the switching circuit SW1 does not transmit the driving signals SD1-SD4 to the input / output pins 135-138. In this example, because the display device 110 includes a charge storage element, the display device 110 can maintain the image even without receiving the driving signals SD1-SD4.

[0067] In this embodiment, the switching circuit SW2 is turned on for a shorter time than the switching circuit SW1. For example, the switching circuit SW2 may be turned on for only one tenth of the switching circuit SW1. Therefore, even if the switching circuit SW1 temporarily stops transmitting the driving signals SD1-SD4, the image displayed by the display device 110 will not be affected by the voltage V PN5 ~V PN8 In one embodiment, the switching circuit SW1 is turned on for approximately 250 μs, and the switching circuit SW2 is turned on for approximately 250 ns.

[0068] In addition, due to the voltage V PN5 ~V PN8 is very small, so even if the display device 110 receives the voltage V PN5 ~V PN8 The image displayed by the display device 110 will not be affected by the voltage V PN5 ~V PN8 In one embodiment, the voltage V PN5 ~V PN8It may be less than one third of the driving signals SD1-SD4. In another embodiment, the voltage V PN5 ~V PN8 It may be less than one quarter of the driving signals SD1-SD4. In other embodiments, the voltage V PN5 ~V PN8 Less than 1V.

[0069] The present invention does not limit when the micro-control circuit 132 turns on the switching circuit SW2. Assuming that the display device 110 displays multiple frames within one second, in one embodiment, the micro-control circuit 132 turns on the switching circuit SW2 between two frames displayed by the display device 110. In another embodiment, the micro-control circuit 132 turns on the switching circuit SW2 at least once during the time it takes for the display device 110 to display a frame. In other words, the micro-control circuit 132 turns on the switching circuit SW2 at least once during a frame.

[0070] Figure 2 FIG. 1 is a possible schematic diagram of the transmission circuit 134 of the present invention. Figure 2 As shown, the switching circuit SW1 is coupled between the image driver 131 and the input / 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 / output pins 135-138 according to the switching signal SEL.

[0071] For example, when the switching signal SEL turns on paths PA1-PA4, paths PA1-PA4 transmit drive signals SD1-SD4 to input / output pins 135-138. When the switching signal SEL turns off paths PA1-PA4, paths PA1-PA4 stop transmitting drive signals SD1-SD4 to input / output pins 135-138. The present invention is not limited to the architecture of the switching circuit SW1. In one embodiment, the switching circuit SW1 includes multiple switches to form paths PA1-PA4. In this embodiment, paths PA1-PA4 are either simultaneously conductive or simultaneously non-conductive. In other embodiments, when one of paths PA1-PA4 is conductive, another of paths PA1-PA4 is non-conductive.

[0072] The switching circuit SW2 has paths PA5 to PA8. The path PA5 is coupled between the sensing circuit 133 and the input / output pin 135 and transmits the reference voltage DK and the voltage V of the pin PN5 according to the switching signal SEL. PN5 The path PA6 is coupled between the sensing circuit 133 and the input / output pin 136, and transmits the reference voltage DK and the voltage V of the pin PN6 according to the switching signal SEL. PN6The 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 of the pin PN7 according to the switching signal SEL. PN7 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 of the pin PN8 according to the switching signal SEL. PN8 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 / output pins 135-138, and then transmit the voltage V 135 ~V 138 To the sensing 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 voltage V 135 ~V 138 In this embodiment, the paths PA5-PA8 are either conductive or non-conductive at the same time. In other embodiments, when one of the paths PA5-PA8 is conductive, the other one of the paths PA5-PA8 is non-conductive.

[0073] In one embodiment, paths coupled to the same I / O pin are not simultaneously conductive. Taking I / O pin 135 as an example, I / O pin 135 is coupled to path PA1 and path PA5. In this example, when path PA1 is conductive, path PA5 is non-conductive. When path PA5 is conductive, path PA1 is non-conductive. The present invention is not limited to the architecture of switching circuit SW2. In one embodiment, switching circuit SW2 includes multiple switches to provide paths PA5-PA8.

[0074] Figure 3 This is a possible schematic diagram of the sensing circuit 133 of the present invention. The sensing circuit 133 includes sensing units 310-340. Sensing unit 310 determines whether area 121 of the capacitive touch device 120 is touched. Sensing unit 320 determines whether area 122 of the capacitive touch device 120 is touched. Sensing unit 330 determines whether area 123 of the capacitive touch device 120 is touched. Sensing unit 340 determines whether area 124 of the capacitive touch device 120 is touched. Since the structures of sensing units 310-340 are the same, only the structure and operation of sensing unit 310 will be described below.

[0075] Sensing unit 310 includes capacitors Cmp and Cmn, a comparator 313, and a controller 314. Capacitor Cmp is coupled between node 311 and the non-inverting input of comparator 313 to provide a reference voltage DK. Capacitor Cmn is coupled between the inverting input of comparator 313 and node 312. In other embodiments, capacitor Cmn may be coupled between the inverting input of comparator 313 and node 311. In this embodiment, capacitors Cmp and Cmn are both variable capacitors.

[0076] 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 In this embodiment, the comparator 313 compares the reference voltage DK with the voltage V PN8 , for generating a comparison signal SCM.

[0077] The controller 314 determines whether a specific area (e.g., area 124) of the capacitive touch device 120 is touched based on the comparison signal SCM. In one embodiment, the controller 314 first generates a reference voltage DK and then provides the reference voltage DK to the non-inverting input of the comparator 313. The controller 314 then determines whether the specific area of ​​the capacitive touch device 120 is touched based on the voltage at the inverting input of the comparator 313. In this embodiment, the controller 314 determines the touch force based on the voltage at the inverting input of the comparator 313.

[0078] For example, during an initial period, the controller 314 first provides a preset voltage to nodes 311 and 312. Consequently, capacitors Cmp and Cmn begin to store charge to generate a reference voltage DK. At this point, the voltages at the inverting and non-inverting inputs of the comparator 313 are approximately equal to the reference voltage DK. If the switching circuit SW2 is turned on, it transmits the reference voltage DK to pins PN5-PN8 of the capacitive touch device 120.

[0079] In this example, when the region 124 of the capacitive touch device 120 is touched, the capacitance of the sensing element 128 in the region 124 changes, causing the voltage V PN8 changes and is no longer equal to the reference voltage DK. Since the voltage at the inverting input of the comparator 313 (i.e., V PN8 ) is not equal to the voltage of the non-inverting input terminal (ie, DK), so the controller 314 knows that the area 124 is touched.

[0080] In one embodiment, the controller 314 generates adjustment signals Sap and San to adjust the capacitance of capacitors Cmp and Cmn so that the voltage at the inverting input of the comparator 313 is equal to the voltage at the non-inverting input (i.e., DK). After the voltage at the inverting input of the comparator 313 is equal to the voltage at the non-inverting input, the controller 314 determines the strength of the touch based on the adjustment amplitude of the capacitance of capacitors Cmp and Cmn. In one embodiment, the controller 314 generates a notification signal to notify the microcontroller 132 of the touch event.

[0081] Figure 4 FIG. 1 is a possible schematic diagram of the display device 110 of the present invention. Figure 4 As shown, the display device 110 has pixels P 11 ~P 44 , but is 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 pixel P 11 ~P 44 According to the start signals ST1-ST4, the data signals DA1-DA4 are received and stored. 11 For example, pixel P 11 According to the start signal ST1, the data signal SD1 is received and stored. In one embodiment, the pixel P 11 ~P 44 Each of them has a storage capacitor (not shown) for storing data signals DA1-DA4.

[0082] In one embodiment, the start-up signals ST1-ST4 are drive signals SD1-SD4. In this example, the data signals DA1-DA4 may also be generated by the graphics driver 131. The graphics driver 131 may provide the data signals DA1-DA4 to the display device 110 via other input / output pins. These input / output pins (i.e., the input / output pins that transmit the data signals DA1-DA4) may or may not be coupled to the capacitive touch device 120.

[0083] In another embodiment, the data signals DA1-DA4 are driving signals SD1-SD4. In this example, the graphics driver 131 may provide the start signals ST1-ST4 to the display device 110 via other input / output pins. These input / output pins (i.e., the input / output pins that transmit the start signals ST1-ST4) may or may not be coupled to the capacitive touch device 120.

[0084] In other embodiments, the driving signals SD1-SD4 are COM / SEG signals. 11 ~P 44 According to the start signals ST1 - ST4 and the COM / SEG signal, the data signals DA1 - DA4 are received and stored.

[0085] In some embodiments, the display device 110 is a passive matrix (PM) display. In this example, the drive signals SD1-SD4 may be referred to as common signals, and the data signals DA1-DA4 may be referred to as segment signals. The potentials of the drive signals SD1-SD4 and the data signals DA1-DA4 are used to change the pixel P. 11 ~P 44 In one embodiment, the pixel P 11 ~P 44 Therefore, when the driving signals SD1-SD4 and the data signals DA1-DA4 disappear, the pixel P 11 ~P 44 The liquid crystal molecules will return to their original positions.

[0086] In other embodiments, the display device 110 further includes a driving circuit (not shown). In this example, the driving circuit may generate the start signals ST1-ST4 or the data signals DA1-DA4 based on the driving signals SD1-SD4. In some embodiments, the driving circuit of the display device 110 generates the start signals ST1-ST4 and the data signals DA1-DA4 based on the driving signals SD1-SD4.

[0087] In this embodiment, since the display device 110 and the capacitive touch device 120 share input and output pins (such as 135-138), the number of input and output pins of the amplitude control circuit 130 can be reduced. PN5 ~V PN8 is much smaller than the voltage of the pins PN1 to PN4 of the display device 110. Therefore, the display device 110 is not affected by the voltage V PN5 ~V PN8 Furthermore, the capacitive touch device 120 outputs a voltage V PN5 ~V PN8 The time is too short to affect the display device 110 .

[0088] Figure 5A Schematic diagram of the voltage level change of the input and output pins 135-138 of the present invention. Symbol V 135~V 138 Respectively represent the voltage levels of the input and output pins 135 to 138. During the display period 511 to 518, the voltage level V 135 ~V 138 Each of the voltage levels V 135 ~V 138 , and the corresponding screen is displayed.

[0089] With voltage level V 135 For example, during display periods 511 and 512, the image driver 131 may set the voltage level V 135 = L1. In other embodiments, the voltage level V 135 The level of the display period 511 may be different from the voltage level V 135 During display periods 513 and 514, the image driver 131 may set the voltage level V 135 is equal to level L2. Level L2 is greater than level L1. In other embodiments, the voltage level V 135 The level of the display period 513 or 514 may be different from the voltage level V 135 The levels of periods 511 and 512 are displayed.

[0090] During the display periods 515 and 516, the image driver 131 may again set the voltage level V 135 = L1. In other embodiments, the voltage level V 135 During the display period 515 and 516, the voltage levels may be different from the voltage level V 135 During display periods 511 or 512, the image driver 131 may set the voltage level V 135 = L2. In other embodiments, the voltage level V 135 The level of the display period 517 or 518 may be different from the voltage level V 135 The present invention does not limit the voltage level V 135 ~V 138 As long as the display device 110 can be driven, the voltage level V 135 ~V 138 Can be any level.

[0091] During the sensing period 521, the sensing circuit 133 performs a sensing operation on the input / output pin 135. When performing the sensing operation, the sensing circuit 133 may provide the reference voltage DK to the input / output pin 135 multiple times. Each time the sensing circuit 133 provides the reference voltage DK to the input / output pin 135, the sensing circuit 133 detects the voltage level V 135The sensing circuit 133 calculates the voltage level V 135 In this example, when the voltage level V 135 When the number of times that the voltage level V is not equal to the reference voltage DK is greater than a preset value, it indicates that a sensing area corresponding to the input / output pin 135 is touched. 135 When the number of times that the voltage is not equal to the reference voltage DK is not greater than the preset value, it indicates that a sensing area corresponding to the input / output pin 135 is not touched.

[0092] During the sensing period 521, the sensing circuit 133 does not perform sensing operations on the input and output pins 136-138. In this example, the voltage level V 136 ~V 138 Each of may be set to level L0, but this is not intended to limit the present invention. In some embodiments, during the sensing period 521, the image driver 131 or the sensing circuit 133 sets the voltage level V 136 ~V 138 Each of is a high level (such as level L2) or a floating level. In one embodiment, the image driver 131 and the sensing circuit 133 may not provide any voltage to the input and output pins 136-138. In this example, the voltage level V 136 ~V 138 Each of is a floating level.

[0093] During the sensing period 522, the sensing circuit 133 performs a sensing operation on the input / output pin 136. The sensing circuit 133 does not perform a sensing operation on the input / output pins 135, 137, and 138. 135 , voltage level V 137 and voltage level V 138 Each of is set to level L0. In other embodiments, the voltage level V 135 , voltage level V 137 and voltage level V 138 Each of may be set to a high level or a floating level. When the sensing circuit 133 performs a sensing operation on the input / output pin 136, the sensing circuit 133 may provide the reference voltage DK to the input / output pin 136 multiple times. Each time the sensing circuit 133 provides the reference voltage DK to the input / output pin 136, the sensing circuit 133 detects the voltage level V 136 In one embodiment, the sensing circuit 133 calculates the voltage level V 136 In this example, when the voltage level V 136 When the number of times that the voltage level V is not equal to the reference voltage DK is greater than a preset value, it indicates that a sensing area corresponding to the input / output pin 136 is touched. 136When the number of times that the voltage is not equal to the reference voltage DK is not greater than the preset value, it indicates that a sensing area corresponding to the input / output pin 136 is not touched.

[0094] During sensing period 523, sensing circuit 133 performs a sensing operation on I / O pin 137. During this period, sensing circuit 133 does not perform a sensing operation on I / O pins 135, 136, and 138. Since the manner in which sensing circuit 133 performs a sensing operation on I / O pin 137 is the same as the manner in which sensing circuit 133 performs a sensing operation on I / O pin 135, further description thereof will be omitted.

[0095] During sensing period 524, sensing circuit 133 performs a sensing operation on I / O pin 138. During this period, sensing circuit 133 does not perform a sensing operation on I / O pins 135-137. Since the sensing circuit 133 performs a sensing operation on I / O pin 138 in the same manner as the sensing circuit 133 performs a sensing operation on I / O pin 135, further description thereof will be omitted.

[0096] In this embodiment, sensing period 521 starts at time TP1, the end of display period 511, and ends at time TP2, the start of display period 512. Sensing period 522 starts at time TP3, the end of display period 513, and ends at time TP4, the start of display period 514. Sensing period 523 starts at time TP5, the end of display period 515, and ends at time TP6, the start of display period 516. Sensing period 524 starts at time TP7, the end of display period 517, and ends at time TP8, the start of display period 518. During each sensing period, sensing circuit 133 detects the voltage level of only one input / output pin.

[0097] Taking the sensing period 521 as an example, from the end time point TP1 to the start time point TP2, the sensing circuit 133 performs sensing operations on the input / output pin 135 multiple times. From the end time point TP1 to the start time point TP2, the sensing circuit 133 does not perform sensing operations on the input / output pins 136 to 138. In addition, during the display period 511, the image driver 131 provides drive signals SD1 to SD4 to the input / output pins 135 to 138. Therefore, the display device 110 presents an image. From the end time point TP1 to the start time point TP2, the image driver 131 stops providing drive signals SD1 to SD4. Therefore, the display device 110 stops presenting an image. Because the interval between the end time point TP1 and the start time point TP2 is very small, it is not easy for the user to notice that the display device 110 has stopped presenting an image.

[0098] Figure 5BSchematic diagram of the change of voltage level of input and output pins 135 and 136 of the present invention. Figure 5B In the display period 531 to 542, the image driver 131 may set the voltage level V 135 and voltage level V 136 Each of is equal to a corresponding level. Therefore, during the display period 531-542, the display device 110 is based on the voltage level V 135 and voltage level V 136 In other embodiments, as long as the voltage level V 135 and voltage level V 136 The display device 110 can be driven so that the display device 110 displays images during the display periods 531 to 542. The voltage level V 135 and voltage level V 136 Each of can be any level.

[0099] During sensing periods 551-553, the sensing circuit 133 performs a sensing operation on the input / output pin 135. During sensing periods 551-553, the sensing circuit 133 does not perform a sensing operation on the input / output pin 136. During sensing periods 554-556, the sensing circuit 133 performs a sensing operation on the input / output pin 136. During sensing periods 554-556, the sensing circuit 133 does not perform a sensing operation on the input / output pin 135. In this embodiment, during each sensing period, the sensing circuit 133 performs a sensing operation on a single input / output pin.

[0100] In one embodiment, sensing period 551 starts at time TP9 at the end of display period 531 and ends at time TP10 at the start of display period 532. Sensing period 552 starts at time TP11 at the end of display period 533 and ends at time TP12 at the start of display period 534. Sensing period 553 starts at time TP13 at the end of display period 535 and ends at time TP14 at the start of display period 536. Sensing period 554 starts at time TP15 at the end of display period 537 and ends at time TP16 at the start of display period 538. Sensing period 555 starts at time TP17 at the end of display period 539 and ends at time TP18 at the start of display period 540. Sensing period 556 starts at time TP19 at the end of display period 541 and ends at time TP20 at the start of display period 542. During each sensing period, sensing circuit 133 detects the voltage level of only one input / output pin.

[0101] Figure 5CSchematic diagram of the voltage level change of the input and output pins 135-137 of the present invention. Figure 5C Only the voltage level V is displayed 135 ~V 137 During the display period 561 to 572, the voltage level V 135 ~V 137 Each of may be equal to a corresponding level. In other embodiments, as long as the voltage level V 135 ~V 137 The display device 110 can be driven so that the display device 110 presents a picture during the display period 561 to 572. The voltage level V 135 ~V 137 Each of may be set to any level. In this example, during the same display period, the voltage level V 135 ~V 137 One of the voltage levels may be different from V 135 ~V 137 The other one.

[0102] During the sensing period 581, the sensing period 582, and the sensing period P1 of the sensing period 583, the sensing circuit 133 performs a sensing operation on the input / output pin 135. During the sensing period 581, the sensing period 582, and the sensing period P1 of the sensing period 583, the sensing circuit 133 does not perform a sensing operation on the input / output pin 136 and the input / output pin 137. When the sensing circuit 133 performs a sensing operation on the input / output pin 135, the voltage level V 136 and voltage level V 137 Each of may be set to level L0, but this is not intended to limit the present invention. In one embodiment, the voltage level V 136 and voltage level V 137 At least one of may be set to a high level or a floating level.

[0103] During period P2 of the sensing period 583, the sensing circuit 133 performs a sensing operation on the input / output pin 136. During the sensing period 584 and the sensing period 585, the sensing circuit 133 performs a sensing operation on the input / output pin 136. During period P3 of the sensing period 586, the sensing circuit 133 performs a sensing operation on the input / output pin 136. During period P2, the sensing period 584, the sensing period 585, and the period P3, the sensing circuit 133 does not perform a sensing operation on the input / output pins 135 and 137. In one embodiment, during period P2, the sensing period 584, the sensing period 585, and the period P3, the voltage level V 135 and voltage level V 137 In other embodiments, during period P2, sensing period 584, sensing period 585 and period P3, the voltage level V135 and voltage level V 137 At least one of may be set to a high level or a floating level.

[0104] During the period P4 of the sensing period 586, the sensing circuit 133 performs a sensing operation on the input / output pin 137. During this period, the sensing circuit 133 does not perform a sensing operation on the input / output pins 135 and 136. In this example, the voltage level V 135 and voltage level V 136 Each of is set to level L0, but it is not intended to limit the present invention. In one embodiment, the voltage level V 135 and voltage level V 136 At least one of may be set to a high level or a floating level.

[0105] In this example, the sum of the sensing period 581, the sensing period 582, and the period P1 is equal to the sum of the period P2, the sensing period 584, the sensing period 585, and the period P3. In other words, the sum of the sensing operations performed by the sensing circuit 133 on one input / output pin is equal to the sum of the sensing operations performed by the sensing circuit 133 on another input / output pin.

[0106] Figure 6A FIG. 1 is another schematic diagram of the operating system of the present invention. Figure 6A As shown, the operating system 600 includes a display device 610, a capacitive touch device 620, and a control circuit 630. In one embodiment, the operating system 600 is a display system. In this example, the display device 610, the capacitive touch device 620, and the control circuit 630 are integrated into a display device.

[0107] The display device 610 has a display area 611, input pins SEG0-SEG3, and COM0-COM3. In one 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 611 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. Each pixel is activated based on the voltage difference between one of the input pins SEG0-SEG3 and one of the pins COM0-COM3.

[0108] The present invention is not limited to the type of display device 610. In one embodiment, the display device 610 is an active matrix display. In this case, each pixel may include a driving transistor (not shown) and a storage capacitor (not shown). The driving transistor charges the storage capacitor, causing the pixel to display a corresponding brightness.

[0109] In another embodiment, the display device 610 is a passive matrix display, such as a twisted nematic liquid crystal display panel (TN LCD panel) or a super twisted nematic liquid crystal display panel (STN LCD panel). In this example, each pixel of the passive matrix display may have a liquid crystal capacitor, without a driver transistor or storage capacitor. One end of the liquid crystal capacitor is directly connected to one of the input pins SEG0-SEG3, and the other end of the liquid crystal capacitor is directly connected to one of the input pins COM0-COM3.

[0110] In other embodiments, display device 610 is a passive matrix organic light-emitting diode (OLED) display. In this example, each pixel of display device 610 comprises only a light-emitting diode (LED), without a driver transistor or storage capacitor. One end (e.g., the anode) of the LED is directly connected to one of input pins SEG0-SEG3, and the other end (e.g., the cathode) of the LED is directly connected to one of input pins COM0-COM3.

[0111] The capacitive touch device 620 includes sensing areas 621-628, sensing pins AN0-AN3 and BN0-BN3. In one embodiment, each sensing area has at least one sensing element, such as a touch sensor. The sensing element is used to determine whether the corresponding area is touched. Since the characteristics of the sensing elements in the sensing areas 621-628 are similar to Figure 1 The characteristics of the sensing elements 125-128 are not described in detail.

[0112] Sensing pins AN0-AN3 and BN0-BN3 output sensing signals generated by the sensing elements. In one possible embodiment, each sensing region 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 elements in sensing regions 621-624 are electrically connected to sensing pins BN0-BN3, respectively. The sensing elements in sensing regions 625-628 are electrically connected to sensing pins AN0-AN3, respectively. In this embodiment, sensing pins AN0-AN3 are electrically connected to input pins SEG3-SEG0, respectively, and sensing pins BN0-BN3 are electrically connected to input pins COM0-COM3, respectively.

[0113] In other embodiments, the capacitive touch device 620 may have more or fewer sensing areas and sensing pins. The present invention is not limited to the type of capacitive touch device 620. In one embodiment, the capacitive touch device 620 is a touch keyboard or a touch pad. In other embodiments, the capacitive touch device 620 may cover the display device 610.

[0114] The control circuit 630 has input / output pins IOA0-IOA3 and IOB0-IOB3. The input / output pins IOA0-IOA3 are electrically connected to the input pins SEG0-SEG3 and the sensing pins AN3-AN0. The input / 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 610 and the capacitive touch device 620 share the input / output pins IOA0-IOA3 and IOB0-IOB3, the number of input / output pins of the control circuit 630 can be reduced.

[0115] During a display period, the control circuit 630 provides segment signals to input pins SEG0-SEG3 via input / output pins IOA0-IOA3, and provides common signals to input pins COM0-COM3 via input / output pins IOB0-IOB3. At this time, the display device 610 displays images based on the potentials of input pins SEG0-SEG3 and COM0-COM3.

[0116] In one embodiment, when the control circuit 630 performs a sensing operation on each of the input / output pins IOA0-IOA3, the control circuit 630 may set the voltage level of each of the input / output pins IOB0-IOB3 to a first predetermined level. When the control circuit 630 performs a sensing operation on each of the input / output pins IOB0-IOB3, the control circuit 630 may set the voltage level of each of the input / output pins IOA0-IOA3 to a second predetermined level.

[0117] In one possible embodiment, the second preset level is relative to the first preset level. For example, when the first preset level is a high level, the second preset level is a low level. When the first preset level is a low level, the second preset level is a high level. In other embodiments, both the first preset level and the second preset level are floating levels. Taking I / O pin 10A0 as an example, the control circuit 630 may not provide any voltage to I / O pin 10A0. Therefore, the voltage level of I / O pin 10A0 is a floating level. In some embodiments, the control circuit 630 sets the impedance of I / O pin 10A0 to a high impedance.

[0118] In one embodiment, the I / O pins IOA0-IOA3 transmit the same type of signals, so the control circuit 630 groups the I / O pins IOA0-IOA3 into a first pin group. Furthermore, since the I / O pins IOB0-IOB3 transmit the same type of signals, the control circuit 530 groups the I / O pins IOB0-IOB3 into a second pin group.

[0119] Figure 6B FIG. 4 is another schematic diagram of the operating system of the present invention. Figure 6B and Figure 6A Similar, but different in that, Figure 6B Resistors R1 through R8 are added. Resistors R1 through R4 are coupled between input / output pins IOA0 through IOA3 and input pins SEG0 through SEG3, respectively. Resistors R5 through R8 are coupled between input / output pins IOB0 through IOB3 and input pins COM0 through COM3, respectively. Taking resistors R1 and R5 as an example, resistor R1 is coupled between input / output pin IOA0 and input pin SEG0, and resistor R5 is coupled between input / output pin IOB0 and input pin COM0. In one embodiment, the impedance of resistors R1 through R8 is approximately between 1 kΩ and 10 kΩ.

[0120] In some embodiments, the display device 610 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 630 performs a sensing operation to detect the touched area of ​​the capacitive touch device 620.

[0121] Figures 7A to 7C Schematic diagram of the voltage level change of the first pin group and the second pin group of the present invention. Since the voltage level changes of the input and output pins IOB0 to IOB3 are similar, Figures 7A to 7C Only the voltage level V of the I / O pin IOB0 is displayed. IOB0 In addition, since the voltage levels of the input and output pins IOA0 to IOA3 change similarly, Figures 7A to 7C Only the voltage level V of I / O pins IOA0~IOA2 is displayed IOA0 ~V IOA2 changes.

[0122] exist Figure 7A In the display period 711 and the display period 712, the control circuit 630 sets the voltage level V IOB0 Equal to level LH, and set the voltage level V IOA0 ~V IOA2 =L1. In other embodiments, during the display period 711, the control circuit 630 sets the voltage level V IOB0 and voltage level V IOA0 ~VIOA2 Different from the voltage level V in the display period 712 IOB0 and voltage level V IOA0 ~V IOA2 The display device 610 is configured according to the voltage level V IOB0 and voltage level V IOA0 ~V IOA2 The corresponding screen is displayed.

[0123] During the sensing period 721, the control circuit 630 sets the voltage level V of the input / output pin IOB0 (the first pin group) IOB0 = is a floating level. In one embodiment, the control circuit 630 does not provide any voltage to the input / output pin 10A0. In this example, the impedance of the input / output pin 10B0 is a high impedance. Therefore, the voltage level V IOB0 is a floating level. During the sensing period 721, the control circuit 630 first performs a sensing operation on the input / output pin 10A0. The control circuit 630 does not perform a sensing operation on the input / output pins 10A1 and 10A2. In one embodiment, the control circuit 630 sets the voltage level V IOA1 and voltage level V IOA2 It is level L0.

[0124] During the display period 713 and the display period 714, the control circuit 630 sets the voltage level V IOB0 Equal to level LM, and set the voltage level V IOA0 ~V IOA2 =L2. In other embodiments, during the display period 713, the control circuit 630 sets the voltage level V IOB0 and voltage level V IOA0 ~V IOA2 Different from the voltage level V in the display period 714 IOB0 and voltage level V IOA0 ~V IOA2 During the display period 713 and the display period 714, the display device 610 is configured to generate a voltage level V IOB0 and voltage level V IOA0 ~V IOA2 , and the corresponding screen is displayed.

[0125] During the sensing period 722, the control circuit 630 sets the voltage level V IOB0 = is a floating level. At this time, the control circuit 630 performs a sensing operation on the input / output pin 10A1. The control circuit 630 does not perform a sensing operation on the input / output pins 10A0 and 10A2. In one embodiment, the control circuit 630 sets the voltage level V IOA0 and voltage level V IOA2 It is level L0.

[0126] During the display period 715 and the display period 716, the control circuit 630 sets the voltage level V IOB0 Equal to level LM, and set the voltage level V IOA0 ~V IOA2 =L1. In other embodiments, during the display period 715, the control circuit 630 sets the voltage level V IOB0 and voltage level V IOA0 ~V IOA2 Different from the voltage level V in the display period 716 IOB0 and voltage level V IOA0 ~V IOA2 During the display period 715 and the display period 716, the display device 610 is operated according to the voltage level V IOB0 and voltage level V IOA0 ~V IOA2 , presenting the corresponding screen. In other embodiments, the control circuit 630 may set the voltage level V IOB0 In this example, the display device 610 may be a passive light emitting diode (PM LED) display device.

[0127] During the sensing period 723, the control circuit 630 sets the voltage level V IOB0 = is a floating level. At this time, the control circuit 630 performs a sensing operation on the input / output pin 10A2. The control circuit 630 does not perform a sensing operation on the input / output pins 10A0 and 10A1. In one embodiment, the control circuit 630 sets the voltage level V IOA0 and voltage level V IOA1 It is level L0.

[0128] In one embodiment, sensing period 721 begins at the end time TP33 of display period 711 and ends at the start time TP34 of display period 712. Sensing period 722 begins at the end time TP35 of display period 713 and ends at the start time TP36 of display period 714. Sensing period 723 begins at the end time TP37 of display period 715 and ends at the start time TP38 of display period 716. During each of sensing periods 721-723, control circuit 630 senses only a single pin in the first pin group and sets the voltage level of each pin in the second pin group to a first predetermined level. After sensing all pins in the first pin group, control circuit 630 switches to sensing each pin in the second pin group and sets the voltage level of each pin in the first pin group to a second predetermined level.

[0129] Please refer to Figure 7B During the display period 731 and the display period 732, the control circuit 630 sets the voltage level V IOB0 Equal to level LH, and set the voltage level V IOA0 and voltage level V IOA1 = L1. Therefore, the display device 610 is configured according to the voltage level V IOB0 , voltage level V IOA0 and voltage level V IOA1 In one embodiment, at the end time point TP39 of the display period 731, the control circuit 630 stops setting the voltage level V IOB0 =LH. Starting from the start time point TP40 of the display period 732, the control circuit 630 sets the voltage level V IOB0 =LH. The sensing period 751 starts from the end time point TP39 and ends at the start time point TP40. From the end time point TP39 to the start time point TP40, the control circuit 630 sets the voltage level V IOB0 = is a floating level. From the end time point TP39 to the start time point TP40, the control circuit 630 performs a sensing operation on the input / output pin 10A0, but does not perform a sensing operation on the input / output pin 10A1. The control circuit 630 may set the voltage level V IOA1 It is level L0.

[0130] During the display period 733 and the display period 734, the control circuit 630 sets the voltage level V IOB0 is level LM, and set the voltage level V IOA0 and voltage level V IOA1 In some embodiments, the control circuit 630 may set the voltage level V IOB0 , voltage level V IOA0 and voltage level V IOA1 In one embodiment, at the end time point TP41 of the display period 733, the control circuit 630 stops setting the voltage level V IOB0 At the start time point TP42 of the display period 734, the control circuit 630 starts to set the voltage level V IOB0 The sensing period 752 is between the end time point TP41 and the start time point TP42. From the end time point TP41 to the start time point TP42, the control circuit 630 sets the voltage level V IOB0= is a floating level. From the end time point TP41 to the start time point TP42, the control circuit 630 performs a sensing operation on the input / output pin 10A0, but does not perform a sensing operation on the input / output pin 10A1. The control circuit 630 may set the voltage level V IOA1 It is level L0.

[0131] During the display period 735 and the display period 736, the control circuit 630 sets the voltage level V IOB0 Equal to level LM, and set the voltage level V IOA0 and voltage level V IOA1 = L1. In other embodiments, the control circuit 630 may set the voltage level V IOB0 , voltage level V IOA0 and voltage level V IOA1 In one embodiment, at the end time point TP43 of the display period 735, the control circuit 630 stops setting the voltage level V IOB0 =Equal to level LM. Starting from the start time point TP44 of the display period 736, the control circuit 630 sets the voltage level V IOB0 = LM. The sensing period 753 starts from the end time point TP43 and ends at the start time point TP44. From the end time point TP43 to the start time point TP44, the control circuit 630 sets the voltage level V IOB0 = is a floating level. From the end time point TP43 until the start time point TP44, the control circuit 630 performs a sensing operation on the input / output pin 10A0, but does not perform a sensing operation on the input / output pin 10A1. The control circuit 630 may set the voltage level V IOA1 It is level L0.

[0132] During the display period 737 and the display period 738, the control circuit 630 sets the voltage level V IOB0 Equal to level LM, and set the voltage level V IOA0 and voltage level V IOA1 = L2. In other embodiments, the control circuit 630 may set the voltage level V IOB0 , voltage level V IOA0 and voltage level V IOA1 In one embodiment, at the end time point TP45 of the display period 737, the control circuit 630 stops setting the voltage level V IOB0 =Equal to level LM. Starting from the start time point TP46 of the display period 738, the control circuit 630 sets the voltage level V IOB0= LM. The sensing period 754 starts from the end time point TP45 and ends at the start time point TP46. From the end time point TP45 to the start time point TP46, the control circuit 630 sets the voltage level V IOB0 = is a floating level. From the end time point TP45 to the start time point TP46, the control circuit 630 performs a sensing operation on the input / output pin 10A1, but does not perform a sensing operation on the input / output pin 10A0. The control circuit 630 may set the voltage level V IOA0 It is level L0.

[0133] During the display period 739 and the display period 740, the control circuit 630 sets the voltage level V IOB0 Equal to level LM, and set the voltage level V IOA0 and voltage level V IOA1 = L1. In other embodiments, the control circuit 630 may set the voltage level V IOB0 , voltage level V IOA0 and voltage level V IOA1 In one embodiment, at the end time point TP47 of the display period 739, the control circuit 630 stops setting the voltage level V IOB0 From the start time point TP48 of the display period 740, the control circuit 630 sets the voltage level V IOB0 = LM. The sensing period 755 starts from the end time point TP47 and ends at the start time point TP48. From the end time point TP47 to the start time point TP48, the control circuit 630 sets the voltage level V IOB0 = is a floating level. From the end time point TP47 until the start time point TP48, the control circuit 630 performs a sensing operation on the input / output pin 10A1, but does not perform a sensing operation on the input / output pin 10A0. The control circuit 630 may set the voltage level V IOA0 It is level L0.

[0134] During the display period 741 and the display period 742, the control circuit 630 sets the voltage level V IOB0 Equal to level LM, and set the voltage level V IOA0 and voltage level V IOA1 = L2. In other embodiments, the control circuit 630 may set the voltage level V IOB0 , voltage level V IOA0 and voltage level V IOA1 In one embodiment, at the end time point TP49 of the display period 741, the control circuit 630 stops setting the voltage level V IOB0=Equal to level LM. Starting from the start time point TP50 of the display period 742, the control circuit 630 sets the voltage level V IOB0 = LM. The sensing period 756 starts from the end time point TP49 and ends at the start time point TP50. From the end time point TP49 to the start time point TP50, the control circuit 630 sets the voltage level V IOB0 = is a floating level. In this embodiment, from the end time point TP49 to the start time point TP50, the control circuit 630 performs a sensing operation on the input / output pin 10A1, but does not perform a sensing operation on the input / output pin 10A0. The control circuit 630 may set the voltage level V IOA0 In other embodiments, during the sensing periods 751 to 756, the control circuit 630 may set the voltage level V IOB0 A high level or a low level.

[0135] Please refer to Figure 7C During the display period 761 and the display period 762, the control circuit 630 sets the voltage level V IOB0 is level LH, and sets the voltage level V IOA0 ~V IOA2 Therefore, the display device 610 is configured according to the voltage level V IOB0 , voltage level V IOA0 ~V IOA2 , presenting a corresponding image. During the sensing period 781, the control circuit 630 performs a sensing operation on the input / output pin 10A0. The control circuit 630 does not perform a sensing operation on the input / output pins 10A1 and 10A2. In this example, the control circuit 630 sets the voltage level V IOA1 and voltage level V IOA2 The sensing period 781 starts from the end time point TP51 ​​of the display period 761 and ends at the start time point TP52 of the display period 762. The control circuit 630 stops setting the voltage level V IOB0 In one embodiment, the control circuit 630 sets the voltage level V IOB0 = is a floating level. From the end time point TP51 ​​to the start time point TP52, the control circuit 630 performs a sensing operation on the input / output pin 10A0 and does not perform a sensing operation on the input / output pins 10A1 and 10A2. The control circuit 630 may set the voltage level V IOA1 and V IOA2 It is level L0.

[0136] During the display period 763 and the display period 764, the control circuit 630 sets the voltage level V IOB0 is level LM, and set the voltage level V IOA0~V IOA2 In other embodiments, the control circuit 630 may set the voltage level V IOB0 and voltage level V IOA0 ~V IOA2 In one embodiment, at the end time point TP53 of the display period 763, the control circuit 630 stops setting the voltage level V IOB0 At the start time point TP54 of the display period 764, the control circuit 630 starts to set the voltage level V IOB0 The sensing period 782 starts from the end time point TP53 and ends at the start time point TP54. From the end time point TP53 to the start time point TP54, the control circuit 630 sets the voltage level V IOB0 = is a floating level. In this embodiment, from the end time point TP53 to the start time point TP54, the control circuit 630 performs a sensing operation on the input / output pin 10A0, but does not perform a sensing operation on the input / output pins 10A1 and 10A2. The control circuit 630 may set the voltage level V IOA1 and voltage level V IOA2 In other embodiments, during the sensing period 782, the control circuit 630 may set the voltage level V IOB0 A high level or a low level.

[0137] During display periods 765 and 766, the control circuit 630 sets the voltage level V IOB0 is level LM, and set the voltage level V IOA0 ~V IOA2 In other embodiments, the control circuit 630 may set the voltage level V IOB0 and voltage level V IOA0 ~V IOA2 In one embodiment, at the end time point TP55 of the display period 765, the control circuit 630 stops setting the voltage level V IOB0 At the start time point TP56 of the display period 766, the control circuit 630 starts to set the voltage level V IOB0 The sensing period 783 starts from the end time point TP55 and ends at the start time point TP56. From the end time point TP55 to the start time point TP56, the control circuit 630 sets the voltage level V IOB0= is a floating level. In this embodiment, from the end time point TP55 to the start time point TP56, the control circuit 630 performs a sensing operation on the input / output pin 10A0 or the input / output pin 10A1, but does not perform a sensing operation on the input / output pin 10A2. In this embodiment, the sensing period 783 includes a period P5 and a period P6. During the period P5, the control circuit 630 performs a sensing operation on the input / output pin 10A0, but does not perform a sensing operation on the input / output pins 10A1 and 10A2. The control circuit 630 may set the voltage level V IOA1 and voltage level V IOA2 =L0. During period P6, the control circuit 630 performs a sensing operation on the input / output pin 10A1, but does not perform a sensing operation on the input / output pin 10A0 and the input / output pin 10A2. The control circuit 630 may set the voltage level V IOA0 and voltage level V IOA2 It is level L0.

[0138] During the display period 767 and the display period 768, the control circuit 630 sets the voltage level V IOB0 is level LM, and set the voltage level V IOA0 ~V IOA2 In other embodiments, the control circuit 630 may set the voltage level V IOB0 and voltage level V IOA0 ~V IOA2 In one embodiment, at the end time point TP57 of the display period 767, the control circuit 630 stops setting the voltage level V IOB0 At the start time point TP58 of the display period 768, the control circuit 630 starts to set the voltage level V IOB0 The sensing period 784 starts from the end time point TP57 and ends at the start time point TP58. From the end time point TP57 to the start time point TP58, the control circuit 630 sets the voltage level V IOB0 = is a floating level. In this embodiment, from the end time point TP57 to the start time point TP58, the control circuit 630 performs a sensing operation on the input / output pin 10A1, but does not perform a sensing operation on the input / output pin 10A0 and the input / output pin 10A2. The control circuit 630 may set the voltage level V IOA0 and voltage level V IOA2 In other embodiments, during the sensing period 784, the control circuit 630 may set the voltage level V IOB0 A high level or a low level.

[0139] During the display period 769 and the display period 770, the control circuit 630 sets the voltage level VIOB0 is level LM, and set the voltage level V IOA0 ~V IOA2 In other embodiments, the control circuit 630 may set the voltage level V IOB0 and voltage level V IOA0 ~V IOA2 In one embodiment, at the end time point TP59 of the display period 769, the control circuit 630 stops setting the voltage level V IOB0 At the start time point TP60 of the display period 770, the control circuit 630 starts to set the voltage level V IOB0 The sensing period 785 starts from the end time point TP59 and ends at the start time point TP60. From the end time point TP59 to the start time point TP60, the control circuit 630 sets the voltage level V IOB0 = is a floating level. In this embodiment, from the end time point TP59 to the start time point TP60, the control circuit 630 performs a sensing operation on the input / output pin 10A1, but does not perform a sensing operation on the input / output pins 10A0 and 10A2. The control circuit 630 may set the voltage level V IOA0 and voltage level V IOA2 In other embodiments, during the sensing period 785, the control circuit 630 may set the voltage level V IOB0 A high level or a low level.

[0140] During the display period 771 and the display period 772, the control circuit 630 sets the voltage level V IOB0 is level LM, and set the voltage level V IOA0 ~V IOA2 In other embodiments, the control circuit 630 may set the voltage level V IOB0 and voltage level V IOA0 ~V IOA2 In one embodiment, at the end time point TP61 of the display period 771, the control circuit 630 stops setting the voltage level V IOB0 At the start time point TP62 of the display period 772, the control circuit 630 starts to set the voltage level V IOB0 The sensing period 786 starts from the end time point TP61 and ends at the start time point TP62. From the end time point TP61 to the start time point TP62, the control circuit 630 sets the voltage level V IOB0 is a floating level. In other embodiments, during the sensing period 786, the control circuit 630 may set the voltage level V IOB0=A high level or a low level. From the end time point TP61 to the start time point TP62, the control circuit 630 performs a sensing operation on the input / output pin 10A1 or 10A2, but does not perform a sensing operation on the input / output pin 10A0. In this embodiment, the sensing period 786 includes periods P7 and P8. During period P7, the control circuit 630 performs a sensing operation on the input / output pin 10A1. At this time, the control circuit 630 does not perform a sensing operation on the input / output pins 10A0 and 10A2. The control circuit 630 may set the voltage level V IOA0 and voltage level V IOA2 =L0. During period P8, the control circuit 630 performs a sensing operation on the input / output pin 10A2, but does not perform a sensing operation on the input / output pin 10A0 and the input / output pin 10A1. The control circuit 630 may set the voltage level V IOA0 and voltage level V IOA1 It is level L0.

[0141] After the control circuit 630 performs a sensing operation on each of the input / output pins IOA0-IOA3, the control circuit 630 then performs a sensing operation on each of the input / output pins IOB0-IOB3. In this example, when the control circuit 630 performs the sensing operation on the input / output pins IOB0-IOB3, the control circuit 630 sets the voltage level of each of the input / output pins IOA0-IOA3 to a floating level, a high level, or a low level.

[0142] Figure 8 This is a schematic diagram illustrating the control circuit 630 of the present invention performing a sensing operation. First, each pin in the first pin group is set to a first predetermined voltage level (step S811). Next, the voltage level of each pin in the second pin group is scanned (step S812). In one embodiment, the control circuit 630 performs a sensing operation on the second pin group. Between display periods, the control circuit 630 performs a sensing operation on a single pin in the second pin group, while omitting the sensing operation on the other pins in the second pin group.

[0143] Next, it is determined whether the control circuit 630 has performed a sensing operation on all pins in the second pin group (step S813). If the control circuit 630 has not performed a sensing operation on all pins in the second pin group, the process returns to step S812. If the control circuit 630 has performed a sensing operation on all pins in the second pin group, step S814 is executed. Step S814 sets each pin of the second pin group to a second preset level. Then, the voltage level of each pin of the first pin group is scanned (step S815). In one possible embodiment, the control circuit 630 scans each pin of the first pin group to perform a sensing operation on the first pin group. Between two display periods, the control circuit 630 performs a sensing operation on a single pin in the first pin group, but does not perform a sensing operation on other pins in the first pin group.

[0144] Next, the control circuit 630 determines whether it has performed a sensing operation on all pins in the first pin group (step S816). If the control circuit 630 has not performed a sensing operation on all pins in the first pin group, the process returns to step S815. If the control circuit 630 has performed a sensing operation on all pins in the second pin group, the sensing operation ends.

[0145] In one embodiment, the second predetermined level in step S814 is relative to the first predetermined level in step S811. For example, when the first predetermined level is high, the second predetermined level is low. When the first predetermined level is low, the second predetermined level is high. In some embodiments, the first predetermined level in step S811 and the second predetermined level in step S814 are both equal to a floating level. In this example, step S811 may not apply any voltage to the first pin group, and step S814 may not apply any voltage to the second pin group.

[0146] In other embodiments, steps S814-S816 are executed earlier than step S811. In this example, the control circuit 630 first sets the voltage level of each pin of the second pin group to the second predetermined level, and then performs a sensing operation on the first pin group. After performing the sensing operation on all pins of the first pin group, the control circuit 630 sets the voltage level of each pin of the first pin group to the first predetermined level, and then performs a sensing operation on the second pin group.

[0147] Figure 9AThis is a possible schematic diagram of a display area according to the present invention. In this embodiment, display area 900A includes a plurality of light-emitting diodes (LEDs). Each LED is coupled to one of input pins SEG0-SEG3 and one of input pins COM0-COM3. Taking LED 910 as an example, the anode of LED 910 is coupled to input pin SEG0, and the cathode of LED 910 is coupled to input pin COM0. In this example, when the voltage difference between input pins SEG0 and COM0 is greater than the turn-on voltage of LED 910, LED 910 is illuminated. When the voltage difference between input pins SEG0 and COM0 is less than the turn-on voltage of LED 910, LED 910 is not illuminated.

[0148] During the sensing period, since the input pins COM0-COM3 may be equal to a high level (or the second predetermined level), even if the input pins SEG0-SEG3 receive a small voltage, the light-emitting diode 910 will not be turned on. Furthermore, since the input pins SEG0-SEG3 may be equal to a low level (or the first predetermined level), even if the input pins COM0-COM3 receive a small voltage, the light-emitting diode 910 will not be turned on. Therefore, during the sensing period, when the control circuit 630 performs a sensing operation on the capacitive touch device 620, the display device 610 will not be disturbed by the sensing operation.

[0149] Figure 9B This is another possible schematic diagram of the display area of ​​the present invention. In this embodiment, display area 900B includes multiple liquid crystal capacitors. Each liquid crystal capacitor is coupled to one of input pins SEG0-SEG3 and one of input pins COM0-COM3. Taking liquid crystal capacitor 920 as an example, liquid crystal capacitor 920 is coupled between input pins SEG0 and COM0.

[0150] During the sensing period, since the voltage level of the input pins COM0-COM3 may be a floating level, even if the input pins SEG0-SEG3 receive a small voltage, the liquid crystal capacitor 920 will not be charged. Furthermore, 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 liquid crystal capacitor 920 will not be charged. Therefore, during the sensing period, when the control circuit 630 performs a sensing operation on the capacitive touch device 620, the sensing operation does not interfere with the display device 610.

[0151] Figure 10 FIG. 1 is another possible schematic diagram of the control circuit of the present invention. Figure 10As shown, the control circuit 1000 includes a display controller 1010, a sensing circuit 1020, and a transmission circuit 1030. The display controller 1010 is used to provide driving signals SSG0, SCM0, and a switching signal SEL. In one embodiment, the driving signal SSG0 is a segment signal, and the driving signal SCM0 is a common signal. In other embodiments, the display controller 1010 integrates Figure 1 The image driver 131 and the micro control circuit 132 are connected. In this example, the driving signal SSG0 serves as one of the driving signals SD1-SD4, and the driving signal SCM0 serves as the other of the driving signals SD1-SD4.

[0152] The sensing circuit 1020 performs a sensing operation. When performing the sensing operation, the sensing circuit 1020 provides a reference voltage DK and receives a sensing voltage V AN3 and sensing voltage V BN0 In one embodiment, the sensing voltage V AN3 is the voltage of the sensing pin AN3 of the capacitive touch device 520, the sensing voltage V BN0 is the voltage of the sensing pin BN0 of the capacitive touch device 620. In other embodiments, the sensing circuit 1020 receives fewer or more sensing voltages, such as the voltages of the sensing pins AN0-AN2 and the sensing pins BN1-BN3. Figure 1 The characteristics of the sensing circuit 133 are similar, so they are not described again.

[0153] Transmission circuit 1030 selects display controller 1010 or sensing circuit 1020 based on switching signal SEL, thereby providing the output of display controller 1010 or sensing circuit 1020 to input / output pins 10A0 and 10B0. During a display period, transmission circuit 1030 provides drive signal SSG0 and drive signal SCM0 to input / output pins 10A0 and 10B0 based on switching signal SEL. During a sensing period, transmission circuit 1030 provides reference voltage DK to one of input / output pins 10A0 and 10B0 based on switching signal SEL, and sets the voltage level of the other of input / output pins 10A0 and 10B0.

[0154] Assume that input / output pin 10A0 belongs to the first pin group, and input / output pin 10B0 belongs to the second pin group. During a first sensing period, display controller 1010 requests transmission circuit 1030 to provide reference voltage DK to input / output pin 10A0 and drive signal SCM0 to input / output pin 10B0. At this time, drive signal SCM0 is equal to a first predetermined level. In other embodiments, display controller 1010 may request transmission circuit 1030 to stop transmitting any signal to input / output pin 10B0. In this example, the voltage level of input / output pin 10B0 is a floating level. In some embodiments, when transmission circuit 1030 provides reference voltage DK to input / output pin 10A0, sensing circuit 1020 may provide a first predetermined level (e.g., a low level or a high level). In this example, transmission circuit 1030 may transmit the first predetermined level provided by sensing circuit 1020 to input / output pin 10B0.

[0155] During the second sensing period, the display controller 1010 requests the transmission circuit 1030 to provide a reference voltage DK to the input / output pin 10B0 and to provide a drive signal SSG0 to the input / output pin 10A0. At this time, the drive signal SSG0 is equal to a second predetermined level. In other embodiments, the display controller 1010 may request the transmission circuit 1030 to stop transmitting any signals to the input / output pin 10A0. In this example, the voltage level of the input / output pin 10A0 is a floating level. In some embodiments, when the transmission circuit 1030 provides the reference voltage DK to the input / output pin 10B0, the sensing circuit 1020 may provide a second predetermined level (e.g., a high level or a low level). In this example, the transmission circuit 1030 may transmit the second predetermined level provided by the sensing circuit 1020 to the input / output pin 10A0.

[0156] After the transmission circuit 1030 provides the reference voltage DK to the input / output pin 10A0, the sensing circuit 1020 detects the voltage V AN3 In this example, when the voltage V AN3 When the voltage is not equal to the reference voltage DK, it indicates that the sensing area corresponding to the sensing pin AN3 of the capacitive touch device 620 is touched. Therefore, the sensing circuit 1020 notifies the display controller 1010, so that the display controller 1010 performs a corresponding action.

[0157] Similarly, after the transmission circuit 1030 provides the reference voltage DK to the input / output pin IOB0, the sensing circuit 1020 detects the voltage V BN0 In this example, when the voltage V BN0When it is not equal to the reference voltage DK, it indicates that the sensing area corresponding to the sensing pin BN0 of the capacitive touch device 620 is touched. Therefore, the sensing circuit 1020 notifies the display controller 1010, so that the display controller 1010 performs another corresponding action.

[0158] Before detecting the voltage of the input / output pin 1000 or 1000, the sensing circuit 1020 first provides a reference voltage DK to the input / output pin 1000 or 1000. Therefore, the sensing operation performed by the sensing circuit 1020 is less susceptible to interference from noise.

[0159] For ease of explanation, Figure 10 Only input / output pins IOA0 and IOB0 are shown, but this is not intended to limit the present invention. In other embodiments, transmission circuit 1030 couples to more input / output pins (e.g., IOA1-IOA3, IOB1-IOB3). The present invention is not limited to the architecture of transmission circuit 1030. In one embodiment, transmission circuit 1030 includes switching circuit 1031 and switching circuit 1032. Switching circuit 1031 and switching circuit 1032 transmit corresponding signals based on switching signal SEL. In other embodiments, display controller 1010 provides two switching signals to control switching circuit 1031 and switching circuit 1032.

[0160] In other embodiments, before the sensing circuit 1020 performs a sensing operation to determine whether the capacitive touch device 620 is touched, the sensing circuit 1020 may send a request signal (not shown) to the display controller 1010. The display controller 1010 responds to the sensing circuit 1020 and sends an approval signal to the sensing circuit 1020. During a specific period, the sensing circuit 1020 may control the voltage levels of the input / output pins 10A0 and 10B0. After the specific period, the display controller 1010 controls the voltage levels of the input / output pins 10A0 and 10B0.

[0161] During a sensing period, the control circuit 1000 scans a portion of the input / output pins and sets another portion of the output pins to a predetermined level (e.g., a low level or a high level) or a floating level. During a sensing period between two display periods, the control circuit 1000 performs a sensing operation. During the same sensing period, the control circuit 1000 may perform a sensing operation on a single input / output pin. Therefore, the display device 610 is not affected by the sensing operation performed by the control circuit 1000 during the sensing period.

[0162] Furthermore, if the display device 610 is a passive matrix display, due to its slow response rate, even if the potential of the input / output pin changes, the passive matrix display does not immediately react. Therefore, even if the input / output pin is set to a reference voltage, the display device 610 is not affected by the reference voltage. In other embodiments, even if the display device 610 is an active matrix display, because the reference voltage is lower than the level of the drive signal, the display device 610 is not affected by the reference voltage. In some embodiments, the sensing period is shorter than the display period, so the display device 610 is not affected by the sensing operation.

[0163] Unless otherwise defined, all terms (including technical and scientific terms) used herein are generally understood by one of ordinary skill in the art to which this invention belongs. Furthermore, unless otherwise expressly stated, dictionary definitions of terms should be interpreted as consistent with their meanings in the relevant technical context and should not be interpreted as idealized or overly formal.

[0164] While the present invention has been disclosed above with reference to preferred embodiments, these are not intended to limit the present invention. Any person skilled in the art may make modifications and variations without departing from the spirit and scope of the present invention. For example, the systems, devices, or methods of the present invention may be implemented in hardware, software, or a combination of hardware and software. Therefore, the scope of protection of the present invention shall be determined by the scope of the claims.

Claims

1. A control circuit, characterized in that: include: a first input-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-output pin, configured to couple a second input pin of the display device and a second sensing pin of the capacitive touch device; a sensing circuit for determining whether the capacitive touch device is touched based on the voltages of the first input / output pin and the second input / output pin; as well as a display controller, during a first display period and a second display period, providing a first driving signal to the display device through the first input / output pin, and providing a second driving signal to the display device through the second input / output pin, in: After an end time point of the first display period, the display controller stops providing the first driving signal and the second driving signal. After the start time point of the second display period, the display controller provides the first driving signal and the second driving signal; From the end time point of the first display period to the start time point of the second display period, the sensing circuit detects the voltage of the first input / output pin and stops detecting the voltage of the second input / output pin. The sensing circuit provides a reference voltage to the first input / output pin and detects the voltage of the first input / output pin. The sensing circuit determines whether a sensing area corresponding to the first sensing pin is touched according to the number of times the voltage of the first input / output pin is not equal to the reference voltage. When the number of times that the voltage of the first input / output pin is not equal to the reference voltage is greater than a preset value, the sensing circuit determines that the sensing area corresponding to the first sensing pin is touched. When the number of times that the voltage of the first input / output pin is not equal to the reference voltage is not greater than the preset value, the sensing circuit determines that the sensing area corresponding to the first sensing pin is not touched.

2. The control circuit according to claim 1, wherein: During a third display period, the display controller provides the first driving signal to the display device through the first input / output pin, and provides the second driving signal to the display device through the second input / output pin. After an end time point of the second display period, the display controller stops providing the first driving signal and the second driving signal. After a start time point of the third display period, the display controller provides the first driving signal and the second driving signal.

3. The control circuit according to claim 2, characterized in that: From the end time point of the second display period to the start time point of the third display period, the sensing circuit detects the voltage of the second input / output pin and stops detecting the voltage of the first input / output pin.

4. The control circuit according to claim 3, characterized in that: From the end time point of the first display period to the start time point of the second display period, the voltage of the second input / output pin is equal to a floating level.

5. The control circuit according to claim 4, characterized in that: From the end time point of the second display period to the start time point of the third display period, the voltage of the first input / output pin is equal to the floating level.

6. The control circuit according to claim 3, characterized in that: From the end time point of the first display period to the start time point of the second display period, the voltage of the second input / output pin is equal to a first preset level. From the end time point of the second display period to the start time point of the third display period, the voltage of the first input / output pin is equal to a second preset level. The second preset level is relative to the first preset level.

7. The control circuit according to claim 2, wherein: From the end time point of the second display period to an intermediate time point, the sensing circuit detects the voltage of the first input / output pin and does not detect the voltage of the second input / output pin. Starting from the intermediate time point until the start time point of the third display period, the sensing circuit detects the voltage of the second input / output pin and does not detect the voltage of the first input / output pin. The intermediate time point is located between the end time point of the second display period and the start time point of the third display period.

8. A display device, characterized in that: include: 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; as well as A control circuit comprising: 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 second sensing pin; a sensing circuit for determining whether the capacitive touch device is touched according to the voltages of the first input / output pin and the second input / output pin; and a display controller, during a first display period and a second display period, providing a first driving signal to the display device through the first input / output pin, and providing a second driving signal to the display device through the second input / output pin, in: During the first display period and the second display period, the display device presents an image according to the first driving signal and the second driving signal. After an end time point of the first display period, the display controller stops providing the first driving signal and the second driving signal. After the start time point of the second display period, the display controller provides the first driving signal and the second driving signal; From the end time point of the first display period to the start time point of the second display period, the sensing circuit detects the voltage of the first input / output pin and stops detecting the voltage of the second input / output pin. The sensing circuit provides a reference voltage to the first input / output pin and detects the voltage of the first input / output pin. The sensing circuit determines whether a sensing area corresponding to the first sensing pin is touched according to the number of times the voltage of the first input / output pin is not equal to the reference voltage. When the number of times that the voltage of the first input / output pin is not equal to the reference voltage is greater than a preset value, the sensing circuit determines that the sensing area corresponding to the first sensing pin is touched. When the number of times that the voltage of the first input / output pin is not equal to the reference voltage is not greater than the preset value, the sensing circuit determines that the sensing area corresponding to the first sensing pin is not touched.

9. The display device according to claim 8, wherein The display device is a passive matrix organic light emitting diode display having a display area for displaying images. The display area has a plurality of light emitting diodes, and one of the plurality of light emitting diodes is directly connected between the first input pin and the second input pin.

Images