CN203311812U - Touch display drive circuit and display device - Google Patents

Abstract

The utility model provides a touch display drive circuit and a display device. The touch display drive circuit includes: a drive transistor for driving a pixel display device for pixel display, for driving the drive transistor for pixel display, and for driving the pixel display device. A compensating driving unit that adjusts the gate-source voltage of the driving transistor so that the compensation amount of the gate-source voltage offsets the threshold voltage when driving the transistor for pixel display, and is used for receiving the touch control signal and according to the received touch control signal Controlling the compensation driving unit to drive the driving transistor to implement a touch sensing unit for pixel display; the driving transistor, the compensation driving unit and the touch sensing unit are connected in sequence. The technical solution of the utility model can realize the integration of touch and drive display, and reduce the thickness of the display screen.

Description

A touch display drive circuit and display device

technical field

The utility model relates to the field of display technology, in particular to a touch display driving circuit and a display device.

Background technique

Touch screens are gaining more and more attention in the consumer electronics market. At present, the touch screen has been widely used as a human-computer interaction interface in portable electronic devices, such as mobile phone screens, notebook computers, digital cameras, and the like. Touch screens can be divided into two types according to technology: external touch screens and in-cell touch screens. The external touch screen is a touch device installed on the display panel. The external touch screen has been widely used in mobile applications such as mobile phones. However, the external touch screen has a high cost and a large thickness. When the touch screen needs to be made larger and larger, the above-mentioned two disadvantages of the external touch screen become more apparent. Currently, consumer electronic products such as mobile phones and tablet computers are required to be smaller in size, thinner in thickness and lighter in weight, and the built-in touch screen can well solve the above two shortcomings because it is integrated in the display panel.

The application of Active Matrix Organic Light Emitting Diode (AMOLED for short) is becoming more and more important. The pixel display device of AMOLED is an organic light-emitting diode (Organic Light-Emitting Diode, hereinafter referred to as OLED). AMOLED can emit light by driving a thin film transistor to generate a driving current in a saturated state, and the driving current drives OLED to emit light. At present, the AMOLED driving circuit generally adopts a traditional 2T1C circuit, and the 2T1C circuit includes two thin film transistors and a storage capacitor.

The inventors found that there are at least the following problems in the prior art: the traditional 2T1C circuit can only perform OLED-driven display without the function of built-in touch, and cannot realize the integration of built-in touch and OLED-driven display, which increases the thickness of the display screen .

Utility model content

The utility model provides a touch display drive circuit and a display device, which can realize the integration of touch and OLED drive display, and reduce the thickness of the display screen.

In order to achieve the above object, the utility model provides a touch display drive circuit, which includes: a drive transistor for driving a pixel display device for pixel display, for driving the drive transistor for pixel display and driving The driving transistor adjusts the gate-source voltage of the driving transistor so that the compensation amount of the gate-source voltage offsets the threshold voltage when the driving transistor performs pixel display, and is used for receiving the touch control signal and according to the received touch The control signal controls the compensation drive unit to drive the drive transistor to perform a touch sensing unit for pixel display;

The driving transistor, the compensation driving unit and the touch sensing unit are connected in sequence.

Optionally, the compensation drive unit includes: a first switch tube and a voltage regulation module;

The gate of the first switch tube is connected to the first control line, the first pole of the first switch tube is connected to the data line, and the second pole of the first switch tube is connected to the voltage regulation module;

The gate of the drive transistor is connected to the voltage regulation module, the first pole of the drive transistor is connected to the voltage regulation module, and the second pole of the drive transistor is connected to the voltage regulation module;

The voltage regulating module is connected to the first power supply and the first control line, the voltage regulating module is connected to the touch sensing unit, and the touch sensing unit is connected to a third power supply.

Optionally, the pixel display device is connected to the first pole of the driving transistor, and the pixel display device is connected to the second power supply. Optionally, the touch sensing unit includes: a photodiode, a sixth switch transistor, a ninth switch transistor, and an eighth switch transistor;

One end of the photodiode is connected to the third power supply, and the other end of the photodiode is connected to the first pole of the ninth switch tube;

The gate of the sixth switch transistor is connected to the third control line, the first pole of the sixth switch transistor is connected to the second pole of the ninth switch transistor and the voltage regulation module, and the sixth switch The second pole of the tube is connected to the pressure regulating module;

The gate of the ninth switch tube is connected to the fourth control line, and the second pole of the ninth switch tube is connected to the voltage regulation module;

The gate of the eighth switch tube is connected to the fourth control line, the first pole of the eighth switch tube is connected to the voltage regulation module and the second pole of the driving transistor, and the eighth switch tube The second pole is connected with the read line.

Optionally, the voltage regulation module includes: a storage capacitor, a second switch tube, a third switch tube, and a fourth switch tube;

The gate of the second switching transistor is connected to the first control line, the first pole of the second switching transistor is connected to the second pole of the ninth switching transistor and the first pole of the sixth switching transistor connected, the second pole of the second switch tube is connected to the storage capacitor and the second pole of the first switch tube;

The gate of the third switching tube is connected to the first control line, the first pole of the third switching tube is connected to the storage capacitor, and the first pole of the third switching tube is connected to the fourth The first pole of the switch tube is connected, and the second pole of the third switch tube is connected to the first power supply;

The gate of the fourth switch tube is connected to the fifth control line, the first pole of the fourth switch tube is connected to the storage capacitor, and the second pole of the fourth switch tube is connected to the eighth switch tube The first pole of the drive transistor is connected to the second pole of the driving transistor.

Optionally, the touch display driving circuit is a multi-stage cascaded circuit, the first control line, the second control line and the third control line receive signals input by the voltage source of the touch display driving circuit at the current stage, and the fourth The control line and the fifth control line are used to receive the voltage output signal of the upper stage.

Optionally, the voltage regulation module further includes: a seventh switch tube;

The gate of the seventh switch tube is connected to the second control line, the first pole of the seventh switch tube is connected to the pixel display device and the second power supply, and the second pole of the seventh switch tube It is connected with the second pole of the sixth switching transistor, the first pole of the driving transistor and the pixel display device.

Optionally, the voltage provided by the first power supply is a reference voltage;

The voltage provided by the third power supply is a reference voltage;

The first pole of the driving transistor is connected to the negative pole of the pixel display device, and the positive pole of the pixel display device is connected to the second power supply.

Optionally, the first switch transistor, the fourth switch transistor, the eighth switch transistor and the ninth switch transistor are P-type thin film transistors;

The second switching transistor, the third switching transistor, the sixth switching transistor, the seventh switching transistor and the driving transistor are N-type thin film transistors.

Optionally, the voltage provided by the second power supply is a reference voltage;

The voltage provided by the third power supply is a reference voltage;

The first electrode of the driving transistor is connected to the positive electrode of the pixel display device, and the negative electrode of the pixel display device is connected to the first power supply.

Optionally, the first switch transistor, the fourth switch transistor, the eighth switch transistor and the ninth switch transistor are N-type thin film transistors;

The second switch transistor, the third switch transistor, the sixth switch transistor, the seventh switch transistor and the drive transistor are P-type thin film transistors.

To achieve the above object, the utility model provides a display device, the display device includes: for driving the first control line, the second control line, the third control line, the fourth control line and the control unit for the fifth control line, the data line driving unit for driving the data line, and the reading unit for reading a signal on the reading line;

The first control line, the second control line, the third control line, the fourth control line, and the fifth control line are connected to the control unit;

The data line driving unit is connected to the data line;

The reading unit is connected to the reading line;

The touch display driving circuit is connected to the data line, the control line, and the reading line;

The touch display driving circuit adopts the touch display driving circuit mentioned above.

The touch display driving circuit and display device provided by the utility model, the touch display driving circuit includes: a driving transistor for driving a pixel display device for pixel display, driving the driving transistor for pixel display, and driving the driving transistor for pixel display. When the transistor is used for pixel display, the gate-source voltage of the drive transistor is adjusted so that the compensation amount of the gate-source voltage offsets the threshold voltage, and the compensation drive unit is used to receive the touch control signal and control the The compensation driving unit drives the driving transistor to perform a touch sensing unit for pixel display; the driving transistor, the compensation driving unit and the touch sensing unit are connected in sequence. The technical scheme of the utility model can realize the integration of touch and OLED drive display, and reduce the thickness of the display screen.

Description of drawings

Fig. 1 is a schematic structural diagram of a touch display driving circuit provided by Embodiment 1 of the present invention;

Fig. 2 is a schematic structural diagram of the touch display driving circuit provided by the second embodiment of the utility model;

3 is a schematic diagram of the input voltage of the touch display driving circuit in the second embodiment;

FIG. 4 is an equivalent circuit diagram of the initialization stage of the touch display driving circuit in Embodiment 2;

5 is an equivalent circuit diagram of the touch and read stages of the touch display drive circuit in Embodiment 2;

6 is an equivalent circuit diagram of the buffer stage of the touch display driving circuit in Embodiment 2;

7 is an equivalent circuit diagram of the charging stage of the touch display driving circuit in Embodiment 2;

8 is an equivalent circuit diagram of the discharge stage of the touch display driving circuit in Embodiment 2;

FIG. 9 is a schematic structural diagram of a touch display driving circuit provided by Embodiment 3 of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the technical solution of the utility model, a touch display driving circuit and a display device provided by the utility model are further described in detail below in conjunction with the accompanying drawings.

Fig. 1 is a schematic structural diagram of a touch display driving circuit provided by Embodiment 1 of the present invention. As shown in Fig. 1, the touch display driving circuit includes: a driving transistor, a touch sensing unit, and a compensation driving unit; wherein, the driving transistor It is used to drive the pixel display device to perform pixel display; the touch sensing unit is used to receive the touch control signal, and control the compensation drive unit to drive the drive transistor to perform pixel display according to the received touch control signal; the compensation drive unit is used to drive the drive transistor to perform pixel display. pixel display; and, when driving the driving transistor for pixel display, adjusting the gate-source voltage of the driving transistor so that the compensation amount of the gate-source voltage cancels the threshold voltage.

Specifically, the gate of the first switching transistor T1 is connected to the first control line CR1, the first pole of the first switching transistor T1 is connected to the data line, and the second pole of the first switching transistor T1 is connected to the voltage regulating module; eighth The gate of the switching tube T8 is connected to the fourth control line CR1_N-1, the first pole of the eighth switching tube T8 is connected to the voltage regulating module and the second pole of the driving transistor T5, and the second pole of the eighth switching tube T8 is connected to the read Take the line connection; the gate of the driving transistor T5 is connected to the voltage regulating module, the first pole of the driving transistor T5 is connected to the voltage regulating module, and the second pole of the driving transistor T5 is connected to the voltage regulating module; the voltage regulating module is connected to the first power supply and the voltage regulating module. The first control line CR1 is connected, the voltage regulating module is connected with the touch sensing unit, and the touch sensing unit is connected with the third power supply. The pixel display device D1 is connected to the first pole of the driving transistor T5, and the pixel display device D1 is connected to the second power supply.

In this embodiment, the pixel display device may be an OLED. The first switching tube T1 and the eighth switching tube T8 are P-type thin film transistors, the driving transistor T5 is an N-type thin film transistor, the voltage provided by the first power supply is the reference voltage VSS, the voltage provided by the second power supply is VDD, and the voltage provided by the third power supply is VDD. The voltage is the reference voltage VSS. Optionally, the first switching transistor T1 and the eighth switching transistor T8 in this embodiment may also be N-type thin film transistors, the driving transistor T5 is a P-type thin film transistor, the voltage provided by the second power supply is the reference voltage VSS, and the first The voltage provided by the power supply is VDD, and the voltage provided by the third power supply is the reference voltage VSS.

In the present invention, if the voltage provided by the first power supply is the reference voltage, then correspondingly, the voltage provided by the second power supply is higher than the reference voltage; if the voltage provided by the second power supply is the reference voltage, then correspondingly, the first The voltage supplied by the power supply is higher than the reference voltage. Wherein, VDD may be at a high level, and correspondingly, VSS as a reference voltage may be at a low level.

In this embodiment, a touch sensing unit and a compensation driving unit are provided in the touch display driving circuit. The touch sensing unit can use light to generate a change in a current signal to cause a change in a voltage signal, and the drive transistor T5 and the eighth switch tube T8 Send the changed voltage signal to the external control circuit, so that the external control circuit can judge the occurrence of the touch. After the occurrence of the touch is judged, the compensation drive unit can adjust the gate-source voltage V _gs of the drive transistor T5, so that the touch display can be driven The driving current of the driving transistor T5 in the circuit in a saturated state has nothing to do with its threshold voltage V _th . Specifically, the voltage regulation module can adjust the size of V _th so that V _th is included in the components of V _gs , so that V _th is offset in the driving current I=K(V _gs -V _th ) ² , and finally the driving current independent of the threshold voltage V _th . Wherein, the driving transistor T5 refers to the transistor that provides the driving current for the pixel display device D1, the threshold voltage refers to the threshold voltage of the driving transistor T5, and the gate-source voltage refers to the gate-source voltage and the source voltage V of the driving transistor T5. The difference between _s .

The touch display driving circuit provided in this embodiment includes: a driving transistor, a touch sensing unit, and a compensation driving unit; wherein, the driving transistor is used to drive a pixel display device to perform pixel display; the touch sensing unit is used to receive a touch control signal, controlling the compensation drive unit to drive the drive transistor to perform pixel display according to the received touch control signal; the compensation drive unit is used to: drive the drive transistor to perform pixel display; and, when driving the When driving the transistor for pixel display, adjust the gate-source voltage of the drive transistor so that the compensation amount of the gate-source voltage is offset with the threshold voltage, which can realize the integration of touch and pixel display device drive and display, and reduce the cost of the display screen. thickness, improve the brightness and uniformity of the display screen, and reduce costs.

Fig. 2 is a schematic structural diagram of a touch display driving circuit provided by Embodiment 2 of the present invention. As shown in Fig. 2 , this embodiment is based on the above Embodiment 1, and the touch sensing unit includes: a photodiode, a sixth The switching tube T6, the ninth switching tube T9 and the eighth switching tube T8.

Photodiodes can also be replaced with touch capacitors. In this embodiment, the photodiode is a photodiode (English: photoelectric diode, PD for short). The case where the photodiode is replaced by a touch capacitor is not shown in FIG. 2 . Wherein, one end of the photodiode is connected to the third power supply VSS, and the other end of the photodiode is connected to the first pole of the ninth switching tube T1; the gate of the sixth switching tube T6 is connected to the third control line CR3, and the sixth switching tube The first pole of T6 is connected to the second pole of the ninth switching tube T9 and the voltage regulating module, and the second pole of the sixth switching tube T6 is connected to the voltage regulating module; the gate of the ninth switching tube T9 is connected to the fourth control line CR1_N -1 connection, the second pole of the ninth switching tube T9 is connected to the voltage regulating module.

In this embodiment, the voltage regulating module includes: a storage capacitor Cs, a second switching tube T2, a third switching tube T3, and a fourth switching tube T4; the gate of the second switching tube T2 is connected to the first control line CR1, and the second switching tube T2 The first pole of the switching tube T2 is connected to the second pole of the ninth switching tube T9 and the first pole of the sixth switching tube T6, and the second pole of the second switching tube T2 is connected to the storage capacitor Cs and the first switching tube T1 The second pole of the third switching tube T3 is connected to the first control line CR1, the first pole of the third switching tube T3 is connected to the storage capacitor Cs, and the first pole of the third switching tube T3 is connected to the fourth switch The first pole of the transistor T4 is connected, and the second pole of the third switch transistor T3 is connected with the first power supply.

Optionally, in this embodiment, the voltage regulation module may further include: a seventh switch tube. The gate of the seventh switching tube T7 is connected to the second control line CR2, the first pole of the seventh switching tube T7 is connected to the pixel display device and the second power supply, the second pole of the seventh switching tube T7 is connected to the sixth switching tube T6 The second pole of the drive transistor T5 is connected to the pixel display device D1. The first pole and the second pole of the seventh switching transistor T7 are connected to both ends of the pixel display device D1, and the seventh switching transistor T7 can be used to short-circuit the pixel display device D1 when the driving transistor T5 generates an incorrect driving current, so as to avoid The pixel display device D1 emits light under the action of an incorrect driving current, thereby generating incorrect luminous intensity to cause display errors; and when the driving transistor T5 generates a correct driving current, the pixel display device D1 is connected to the driving transistor T5, so that the pixel The display device D1 emits light under the action of the correct driving current to ensure normal display.

The voltage provided by the first power supply in this embodiment is the reference voltage VSS; the voltage provided by the third power supply is the reference voltage VSS; the first pole of the driving transistor T5 is connected to the negative pole of the pixel display device D1, and the positive pole of the pixel display device D1 is connected to the negative pole of the pixel display device D1. The second power supply VDD is connected.

Among them, the first switching tube T1, the fourth switching tube T4, the eighth switching tube T8 and the ninth switching tube T9 are P-type thin film transistors; the second switching tube T2, the third switching tube T3, the sixth switching tube T6, the The seven switching transistors T7 and the driving transistor T5 are N-type thin film transistors.

The working process of the touch display driving circuit in this embodiment will be described in detail below with reference to FIG. 3 to FIG. 8 . 3 is a schematic diagram of the input voltage of the touch display driving circuit in the second embodiment, wherein: a is the initialization phase, b is the touch reading phase, c is the buffering phase, d is the charging phase, and e is the light emitting phase. FIG. 4 is a schematic diagram of an equivalent circuit in the initialization stage of the touch display driving circuit in Embodiment 2. As shown in FIGS. The voltage provided is high level, the voltage provided by the third control line CR3 is high level, the fourth control line CR1_N-1 is high level, and the fifth control line CR2_N-1 is high level. At this time, the second The switching tube T2, the third switching tube T3, the sixth switching tube T6 and the seventh switching tube T7 are turned on, and the first switching tube T1, the fourth switching tube T4, the eighth switching tube T8 and the ninth switching tube T9 are turned off. Therefore, the equivalent circuit schematic diagram of the touch display driving circuit initialization stage in Figure 2 is shown in Figure 4. At this time, VDD is written into point A, VA=VB=VDD, VC=VSS, and the voltage across the storage capacitor Cs is VCs=VA -VC=VDD-VSS. Wherein, VSS is a reference voltage provided by the first power supply, VDD is a voltage provided by the second power supply, and the voltage VDD provided by the second power supply is higher than the reference voltage VSS provided by the first power supply.

Fig. 5 is a schematic diagram of an equivalent circuit in the touch and read stages of the touch display drive circuit in Embodiment 2. As shown in Fig. 3 and Fig. 5, when the touch sensing unit is touched and the external drive circuit is read, the first control The voltage provided by the line CR1 is high level, the voltage provided by the second control line CR2 is high level, the voltage provided by the third control line CR3 is low level, the fourth control line CR1_N-1 is low level, and the fifth control line CR1_N-1 is low level. The control line CR2_N-1 is at a high level. At this time, the second switching tube T2, the third switching tube T3, the seventh switching tube T7, the eighth switching tube T8 and the ninth switching tube T9 are turned on, and the first switching tube T1, The fourth switching tube T4 and the sixth switching tube T6 are turned off. Therefore, the schematic diagram of the equivalent circuit in the initialization stage of the touch display driving circuit in FIG. 2 is shown in FIG. 5 , and point A is connected to the photodiode through the ninth switching transistor T9 at this time. The leakage current of the photodiode is different when it is not touched and when it is touched. Specifically, when no touch occurs, the photodiode will generate a leakage current when it is irradiated by light, and the leakage current is large at this time; when a touch occurs, the light irradiated on the photodiode is blocked, and at this time, a The leakage current is small, and the change of the leakage current when no touch occurs or when there is a touch causes the voltage signal of point A to change. The line is connected to the external control circuit, and the external control circuit analyzes the changing voltage signal. The leakage current generated by the photodiode under the irradiation of light is larger than that generated by the photodiode when there is no light irradiation, so it can be judged that there is Touch happens.

Fig. 6 is a schematic diagram of an equivalent circuit in the buffer stage of the touch display driving circuit in the second embodiment. As shown in Fig. 3 and Fig. 6, the voltage provided by the first control line CR1 is high level, and the voltage provided by the second control line CR2 is High level, the voltage provided by the third control line CR3 is low level, the fourth control line CR1_N-1 is high level, and the fifth control line CR2_N-1 is low level, at this time the second switch tube T2, the first The third switching tube T3, the fourth switching tube T4 and the seventh switching tube T7 are turned on, and the first switching tube T1, the sixth switching tube T6, the eighth switching tube T8 and the ninth switching tube T9 are turned off. Therefore, the equivalent circuit schematic diagram of the initialization stage of the touch display driving circuit in Figure 2 is shown in Figure 6. At this time, point A is discharged to the voltage VSS provided by the first power supply through the storage capacitor Cs, and the level of point A becomes low, falling to VSS+ V _th , wherein, V _th is the threshold voltage of the driving transistor T5, so as to eliminate the influence of the touch in the previous stage.

Fig. 7 is a schematic diagram of an equivalent circuit in the charging stage of the touch display driving circuit in the second embodiment. As shown in Fig. 3 and Fig. 7, the voltage provided by the first control line CR1 is low level, and the voltage provided by the second control line CR2 is High level, the voltage provided by the third control line CR3 is high level, the fourth control line CR1_N-1 is high level, and the fifth control line CR2_N-1 is low level. Therefore, the equivalent circuit schematic diagram of the initialization stage of the touch display driving circuit in FIG. 2 is shown in FIG. The switching tube T2, the third switching tube T3, the eighth switching tube T8 and the ninth switching tube T9 are turned off. The data voltage V _data provided by the data line is input, and the storage capacitor Cs is charged. At this time, the voltage at point A is VDD, the voltage at point B is V _data , the voltage at point C is VDD-V _th , and the voltage at both ends of the storage capacitor Cs is VCs= VB-VC=V _data -VDD+V _th . Wherein, V _th is the threshold voltage of the driving transistor T5.

Fig. 8 is a schematic diagram of an equivalent circuit in the discharge stage of the touch display driving circuit in Embodiment 2. As shown in Fig. 3 and Fig. 8, the voltage provided by the first control line CR1 is high level, and the voltage provided by the second control line CR2 is low level, the voltage provided by the third control line CR3 is low level, the fourth control line CR1_N-1 is high level, and the fifth control line CR2_N-1 is low level, at this time the second switch tube T2, the first The third switching tube T3 and the fourth switching tube T4 are turned on, and the first switching tube T1 , the sixth switching tube T6 , the seventh switching tube T7 , the eighth switching tube T8 and the ninth switching tube T9 are turned off. Therefore, the equivalent circuit schematic diagram of the initialization stage of the touch display driving circuit in FIG. 2 is shown in FIG. 8. At this time, the voltage across the storage capacitor Cs is used to drive the driving transistor T5 of the pixel display device D1, and the pixel display device D1 starts to emit light. The gate A point of the drive transistor T5 is directly connected to the B terminal of the storage capacitor Cs, VA=VB, the voltage of point C is VSS, the gate-source voltage V _gs of the drive transistor T5 =VAC=VBC=VCs=V _data -VDD+V _th , the data voltage provided by the data line is higher than the voltage VDD provided by the second power supply. At this time, the current flowing through the pixel display device D1 is: I=K(V _gs −V _th ) ² =K(V _data −VDD+V _th −V _th ) ² =K(V _data −VDD) ² . Wherein, K=μ _eff ×C _OX ×(W/L)/2, wherein, μ _eff is the effective mobility of the carrier of the drive transistor T5, C _OX is the channel width of the drive transistor T5, and L is the drive transistor T5 channel length.

In this embodiment, the touch sensing unit of the touch display drive circuit transmits the changed voltage signal to the external control circuit under the control of the drive transistor and the eighth switch tube, so as to determine the occurrence of touch. Afterwards, the storage capacitor Cs is charged, so that the voltage V _data provided by the data line and the threshold voltage V _th of the driving tube are written into the storage capacitor, that is, the voltage at both ends of the storage capacitor VCs=V _data -VDD+V _th during the charging phase, Then, the storage capacitor provides the gate-source voltage to the driving transistor to compensate the threshold voltage of the driving transistor. The driving transistor drives the pixel display device under the control of the voltage regulation module, and the driving current flowing through the driving transistor has nothing to do with the threshold voltage V _th of the driving transistor, which avoids the unevenness and drift of the driving current flowing through the pixel display device due to the threshold voltage V _th At the same time, the drive current flowing through the drive transistor has nothing to do with the pixel display device's own turn-on voltage V _th-oled , avoiding the drive current from being affected by the increase of its own turn-on voltage V _th-oled caused by the degradation of the pixel display device, Therefore, the uniformity of the driving current flowing through the pixel display device is improved.

Fig. 9 is a schematic structural diagram of the touch display drive circuit provided by the third embodiment of the present invention. As shown in Fig. 9, on the basis of the first embodiment above, the touch sensing unit of this embodiment includes: a photodiode, a sixth switch tube T6 , the ninth switching tube T9 and the eighth switching tube T8.

In this embodiment, the photodiode (English: photoelectric diode, PD for short) may be replaced with a touch capacitor. The case where the photodiode is replaced by a touch capacitor is not shown in FIG. 2 . Wherein, one end of the photodiode is connected to the voltage VDD provided by the third power supply, and the other end of the photodiode is connected to the first pole of the ninth switching transistor T1; the gate of the sixth switching transistor T6 is connected to the third control line CR3, and the second The first pole of the sixth switching tube T6 is connected to the second pole of the ninth switching tube T9 and the voltage regulating module, and the second pole of the sixth switching tube T6 is connected to the voltage regulating module; the gate of the ninth switching tube T9 is connected to the fourth The control line CR1_N-1 is connected, and the second pole of the ninth switching tube T9 is connected to the voltage regulating module.

In this embodiment, the voltage regulating module includes: a storage capacitor Cs, a second switching tube T2, a third switching tube T3, and a fourth switching tube T4; the gate of the second switching tube T2 is connected to the first control line CR1, and the second switching tube T2 The first pole of the switching tube T2 is connected to the second pole of the ninth switching tube T9 and the first pole of the sixth switching tube T6, and the second pole of the second switching tube T2 is connected to the storage capacitor Cs and the first switching tube T1 The second pole of the third switching tube T3 is connected to the first control line CR1, the first pole of the third switching tube T3 is connected to the storage capacitor Cs, and the first pole of the third switching tube T3 is connected to the fourth switch The first pole of the transistor T4 is connected, and the second pole of the third switch transistor T3 is connected with the first power supply.

Optionally, in this embodiment, the voltage regulation module may further include: a seventh switch tube. The gate of the seventh switching tube T7 is connected to the second control line CR2, the first pole of the seventh switching tube T7 is connected to the pixel display device and the second power supply, the second pole of the seventh switching tube T7 is connected to the sixth switching tube T6 The second pole of the drive transistor T5 is connected to the pixel display device D1. The first pole and the second pole of the seventh switching transistor T7 are connected to both ends of the pixel display device D1, and the seventh switching transistor T7 can be used to short-circuit the pixel display device D1 when the driving transistor T5 generates an incorrect driving current, so as to avoid The pixel display device D1 emits light under the action of an incorrect driving current, thereby generating incorrect luminous intensity to cause display errors; and when the driving transistor T5 generates a correct driving current, the pixel display device D1 is connected to the driving transistor T5, so that the pixel The display device D1 emits light under the action of the correct driving current to ensure normal display.

The voltage provided by the first power supply in this embodiment is the reference voltage VSS; the voltage provided by the third power supply is VDD; the first pole of the driving transistor T5 is connected to the positive pole of the pixel display device D1, and the negative pole of the pixel display device D1 is connected to the first pole of the pixel display device D1. Power supply provides the reference voltage VSS connection.

Among them, the first switching tube T1, the fourth switching tube T4, the eighth switching tube T8 and the ninth switching tube T9 are N-type thin film transistors; the second switching tube T2, the third switching tube T3, the sixth switching tube T6, the The seven switching transistors T7 and the driving transistor T5 are P-type thin film transistors.

For the working principle of the touch display driving circuit in this embodiment, please refer to the second embodiment above, and will not be described in detail here.

The difference between the touch display driving circuit of Embodiment 2 and Embodiment 3 is that in Embodiment 3, one end of the photodiode is connected to the voltage VDD provided by the third power supply, and the other end of the photodiode is connected to the first pole of the ninth switching tube T1. connection; the first switching tube T1, the fourth switching tube T4, the eighth switching tube T8 and the ninth switching tube T9 are N-type thin film transistors; the second switching tube T2, the third switching tube T3, the sixth switching tube T6, the The seven switching transistors T7 and the driving transistor T5 are P-type thin film transistors. Moreover, the voltage provided by the first power supply is the reference voltage VSS, the voltage provided by the second power supply is VDD, and the voltage provided by the third power supply is VDD; the first pole of the driving transistor T5 is connected to the positive pole of the pixel display device D1, and the pixel display device D1 The negative pole of is connected to the reference voltage VSS provided by the first power supply. The voltage provided by the second power supply may be higher than the reference voltage. Wherein, VDD may be at a high level, and correspondingly, VSS as a reference voltage may be at a low level.

In the touch display drive circuit provided in this embodiment, the touch sensing unit transmits the changed voltage signal to the external control circuit under the control of the drive transistor and the eighth switch tube, so as to determine the occurrence of touch. After the occurrence, the storage capacitor Cs is charged, so that the voltage V _data provided by the data line and the threshold voltage V _th of the drive tube are written into the storage capacitor, that is, the voltage at both ends of the storage capacitor VCs=V _data -VDD+V _th during the charging phase , and then the storage capacitor provides the gate-source voltage to the driving transistor to compensate the threshold voltage of the driving transistor. The driving transistor drives the pixel display device under the control of the voltage regulation module, and the driving current flowing through the driving transistor has nothing to do with the threshold voltage V _th of the driving transistor, which avoids the unevenness and drift of the driving current flowing through the pixel display device due to the threshold voltage V _th At the same time, the drive current flowing through the drive transistor has nothing to do with the pixel display device's own turn-on voltage V _th-oled , avoiding the drive current from being affected by the increase of its own turn-on voltage V _th-oled caused by the degradation of the pixel display device, Therefore, the uniformity of the driving current flowing through the pixel display device is improved.

The touch display driving circuits provided in the second and third embodiments above are applicable not only to polysilicon thin film transistors but also to other transistors in practical applications.

It should be noted that, in the present utility model, in the first switching tube T1, the second switching tube T2, the third switching tube T3, the fourth switching tube T4, the drive transistor T5, the sixth switching tube T6, the seventh switching tube, In each transistor of the eighth switch tube and the ninth switch tube, the first pole and the second pole serve as source and drain. In the transistor, the structures of the first pole and the second pole are the same. Among the first pole and the second pole, one pole that transmits carriers serves as a source, and one pole that receives carriers serves as a drain. In actual application, for a transistor, according to the position and function of the transistor in the circuit, the first pole can be used as the source, and accordingly, the second pole can be used as the drain; or, the first pole can be used as the drain, then the corresponding ground, and the second pole as source.

Embodiment 4 of the present invention provides a display device, which includes: a control unit, a first control line, a second control line, a third control line, a fourth control line, a fifth control line, a data line drive unit, Data line, reading unit, reading line and touch display drive circuit, the control unit is used to drive the first control line, the second control line, the third control line, the fourth control line and the fifth control line, the data line drive unit It is used to drive the data line, the reading unit is used to read the signal on the reading line, the touch display driving circuit is connected with the first control line, the second control line, the third control line, the fourth control line, the fifth control line, Data line and read line connection.

The display device provided in Embodiment 4 adopts the touch display driving circuit in Embodiment 2 or Embodiment 3 above. For its specific implementation, please refer to Embodiment 2 or Embodiment 3 above, and no specific description is given here.

The display device provided in Embodiment 4 includes: a control unit for driving the first control line, the second control line, the third control line, the fourth control line and the fifth control line, and a data line for driving the data line A drive unit, a reading unit for reading signals on the reading line; the first control line, the second control line, the third control line, the fourth control line, and the fifth control line are connected to the control unit; the data line drive The unit is connected to the data line; the reading unit is connected to the reading line; the touch display driving circuit is connected to the data line, the control line, and the reading line; the touch display driving circuit adopts the above touch display driving circuit. It can realize the integration of touch and OLED drive display, and reduce the thickness of the display screen.

Embodiment 5 of the present invention provides a touch display driving method. The touch display driving method is based on a touch display driving circuit. The touch display driving circuit includes: a pixel display device, a first switching tube, a voltage regulation module, a driving transistor, a touch sensing unit, which includes:

Step 101, the first switch tube is turned off under the control of the first control line, so that the data line provides voltage to the storage capacitor through the first switch tube;

Step 102, the eighth switch tube is turned off under the control of the fourth control line, so that the reading line reads the current flowing through the driving transistor, and determines whether there is a touch;

Step 103 , the voltage regulating module is controlled by the first control line, the second control line, the third control line, the fourth control line and the fifth control line, so that the driving tube drives the pixel display device to emit light.

The touch display driving method of the fifth embodiment can be realized based on the touch display driving circuit in the second or third embodiment above. For the specific implementation, please refer to the second or third embodiment above, and will not be described in detail here.

The touch display driving method provided in this embodiment is based on a touch display driving circuit, a driving transistor, a touch sensing unit, and a compensation driving unit; wherein, the driving transistor is used to drive a pixel display device to perform pixel display; The touch sensing unit is configured to receive a touch control signal, and control the compensation drive unit to drive the drive transistor to perform pixel display according to the received touch control signal; the compensation drive unit is used to: drive the drive transistor to performing pixel display; and, when driving the drive transistor to perform pixel display, adjusting the gate-source voltage of the drive transistor so that the compensation amount of the gate-source voltage is offset from the threshold voltage, which can realize touch and pixel display The device drives the integration of the display and reduces the thickness of the display screen.

In the present invention, the touch display drive circuit may be a multi-stage cascaded circuit, and in each stage, the first control line, the second control line and the third control line receive the voltage of the touch display drive circuit of the current stage. source input signal, the fourth control line and the fifth control line receive the voltage output signal of the upper stage; of course, the input signal access method in this embodiment is not limited to this, for example, the first The single-signal input terminals of the four control lines and the fifth control line are externally connected with power supply voltage signals instead of receiving the voltage output signal of the upper stage.

It can be understood that, the above embodiments are only exemplary embodiments adopted to illustrate the principles of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present utility model, and these variations and improvements are also regarded as the protection scope of the present utility model.

Claims (12)

1. A touch display drive circuit, characterized in that it comprises: a drive transistor for driving a pixel display device for pixel display, for driving the drive transistor for pixel display, and for driving the drive transistor for pixel display A compensation driving unit that adjusts the gate-source voltage of the driving transistor so that the compensation amount of the gate-source voltage cancels the threshold voltage, and is used for receiving a touch control signal and controlling the compensation driving unit according to the received touch control signal A touch sensing unit that drives the drive transistor to perform pixel display; The driving transistor, the compensation driving unit and the touch sensing unit are connected in sequence. 2. The touch display drive circuit according to claim 1, characterized in that The compensation drive unit includes: a first switch tube and a voltage regulating module; The gate of the first switch tube is connected to the first control line, the first pole of the first switch tube is connected to the data line, and the second pole of the first switch tube is connected to the voltage regulation module; The gate of the drive transistor is connected to the voltage regulation module, the first pole of the drive transistor is connected to the voltage regulation module, and the second pole of the drive transistor is connected to the voltage regulation module; The voltage regulating module is connected to the first power supply and the first control line, the voltage regulating module is connected to the touch sensing unit, the touch sensing unit is connected to the third power supply connect. 3. The touch display driving circuit according to claim 2, wherein the pixel display device is connected to the first pole of the driving transistor, and the pixel display device is connected to the second power supply. 4. The touch display driving circuit according to claim 1, wherein the touch sensing unit comprises: a photodiode, a sixth switch tube, a ninth switch tube, and an eighth switch tube; One end of the photodiode is connected to the third power supply, and the other end of the photodiode is connected to the first pole of the ninth switch tube; The gate of the sixth switch transistor is connected to the third control line, the first pole of the sixth switch transistor is connected to the second pole of the ninth switch transistor and the voltage regulation module, and the sixth switch The second pole of the tube is connected to the pressure regulating module; The gate of the ninth switch tube is connected to the fourth control line, and the second pole of the ninth switch tube is connected to the voltage regulating module; The gate of the eighth switch tube is connected to the fourth control line, the first pole of the eighth switch tube is connected to the voltage regulation module and the second pole of the driving transistor, and the eighth switch tube The second pole is connected with the read line. 5. The touch display driving circuit according to claim 2, wherein the voltage regulation module comprises: a storage capacitor, a second switch tube, a third switch tube, and a fourth switch tube; The gate of the second switching transistor is connected to the first control line, the first pole of the second switching transistor is connected to the second pole of the ninth switching transistor and the first pole of the sixth switching transistor connected, the second pole of the second switch tube is connected to the storage capacitor and the second pole of the first switch tube; The gate of the third switching tube is connected to the first control line, the first pole of the third switching tube is connected to the storage capacitor, and the first pole of the third switching tube is connected to the fourth The first pole of the switch tube is connected, and the second pole of the third switch tube is connected to the first power supply; The gate of the fourth switch tube is connected to the fifth control line, the first pole of the fourth switch tube is connected to the storage capacitor, and the second pole of the fourth switch tube is connected to the eighth switch tube The first pole of the drive transistor is connected to the second pole of the driving transistor. 6. The touch display driving circuit according to claim 5, wherein the touch display driving circuit is a multi-stage cascaded circuit, and the first control line, the second control line and the third control line receive The signal input by the voltage source of the touch display driving circuit, the fourth control line and the fifth control line receive the voltage output signal of the upper stage. 7. The touch display driving circuit according to claim 5, wherein the voltage regulation module further comprises: a seventh switch tube; The gate of the seventh switch tube is connected to the second control line, the first pole of the seventh switch tube is connected to the pixel display device and the second power supply, and the second pole of the seventh switch tube It is connected with the second pole of the sixth switching transistor, the first pole of the driving transistor and the pixel display device. 8. The touch display driving circuit according to claim 5, wherein the voltage provided by the first power supply is a reference voltage; The voltage provided by the third power supply is a reference voltage; The first pole of the driving transistor is connected to the negative pole of the pixel display device, and the positive pole of the pixel display device is connected to the second power supply. 9. The touch display driving circuit according to claim 8, wherein the first switch tube, the fourth switch tube, the eighth switch tube and the ninth switch tube are P-type thin film transistors ; The second switching transistor, the third switching transistor, the sixth switching transistor, the seventh switching transistor and the driving transistor are N-type thin film transistors. 10. The touch display driving circuit according to claim 5, wherein the voltage provided by the second power supply is a reference voltage; The voltage provided by the third power supply is a reference voltage; The first pole of the driving transistor is connected to the positive pole of the pixel display device, and the negative pole of the pixel display pixel display device is connected to the first power supply. 11. The touch display driving circuit according to claim 10, wherein the first switch tube, the fourth switch tube, the eighth switch tube and the ninth switch tube are N-type thin film transistors ; The second switch transistor, the third switch transistor, the sixth switch transistor, the seventh switch transistor and the drive transistor are P-type thin film transistors. 12. A display device, characterized in that it comprises: for driving the first control line, the second control line, the third control line, the fourth control line and the fifth control line The control unit, the data line driving unit for driving the data line, and the reading unit for reading the signal on the reading line; The first control line, the second control line, the third control line, the fourth control line, and the fifth control line are connected to the control unit; The data line driving unit is connected to the data line; The reading unit is connected to the reading line; The touch display driving circuit is connected to the data line, the control line, and the reading line; The touch display driving circuit adopts the touch display driving circuit described in any one of claims 1-11 above.

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