Touch / display driving circuit and apparatus including the same

Abstract

To provide a touch / display driving circuit capable of performing stable display operation and touch operation regardless of input power types, and an apparatus including the same.SOLUTION: A power circuit according to the present embodiment, which is coupled with a first power line and a second power line, can include a multiplexor which selects and outputs either one of a first voltage supplied over the first power line or a second voltage supplied over the second power line. Furthermore, the power circuit generates a first driving voltage and a second driving voltage using the voltage supplied from the multiplexor, recognizes presence / absence of the first voltage supplied over the first power line, and can include a first power circuit which does not output the first driving voltage if the first voltage is unrecognized.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] This embodiment relates to a drive circuit for touch and display and a device including the same.

Background Art

[0002] Display devices capable of touch input on a display screen (for example, touch / display devices) are applied to various electronic devices.

[0003] A touch / display device can embody touch and display in various forms by attaching a touch panel to a display panel and using an on-cell method, or by incorporating touch electrodes into the display panel and using an in-cell method.

[0004] By using a part of a common electrode in a touch / display device as a touch electrode, touch and display can be simultaneously embodied in one device. By time-division multiplexing one time interval, it can be divided into a display drive period for transmitting video data to the common electrode and a touch drive period for transmitting a touch drive signal to the touch electrode, and the operation cycles of touch and display can be adjusted.

[0005] In order to reduce the power consumption of a display device, it is necessary to supply power separately in the time intervals when the display device displays and when it performs touch driving. When the display device performs a display operation, power for touch sensing is also consumed together, and when the display device performs a touch sensing operation, power for display is also consumed together. Therefore, if the supplied power is not adjusted regardless of the type of operation of the display device, the power consumption of the panel will increase.

[0006] Even when power for display driving and power for touch driving are supplied separately in a display device, if the circuit for touch driving is not distinguished from the circuit for display driving, and only power for touch sensing is supplied, the circuit for display driving may not function correctly. A touch sensing circuit designed to drive both touch and display needs to be powered stably in either time-division interval (i.e., display interval and touch interval). [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Korean Published Patent Publication No. 10-2019-0045481 [Patent Document 2] Korean Published Patent Publication No. 10-2018-0020787 [Patent Document 3] U.S. Patent Application Publication No. 2009 / 0085655 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Against this backdrop, the object of the present invention is to provide a touch / display driving circuit and an apparatus including the same that can stably perform display operation and touch operation regardless of the type of input power supply. [Means for solving the problem]

[0009] To achieve the aforementioned objectives, in one aspect, this embodiment can provide a power supply circuit including a multiplexer connected to a first power line and a second power line, which selects and outputs either a first voltage supplied via the first power line or a second voltage supplied via the second power line; and a first power supply circuit that generates a first drive voltage and a second drive voltage using the voltage supplied from the multiplexer, recognizes the presence or absence of the first voltage supplied via the first power line, and does not output the first drive voltage if the first voltage is not recognized.

[0010] To achieve the aforementioned objectives, in other respects, this embodiment can provide a touch sensing circuit comprising: a multiplexer connected to a first line to receive a main voltage and connected to a second line to receive a sub-voltage; a power management circuit that receives a voltage which the multiplexer selects to output, either the main voltage or the sub-voltage; and a touch modulation circuit connected to the power management circuit that modulates a signal transmitted to a touch electrode, wherein the multiplexer changes the type of voltage selected depending on the driving mode of the panel.

[0011] To achieve the aforementioned objectives, in other respects, this embodiment can provide a touch sensing circuit that includes one or more buck converters that convert an output voltage to a level lower than the input voltage; one or more power management circuits that generate a voltage and transmit it to a source readout circuit or a touch modulation circuit; and one or more multiplexers that select one of a plurality of input power supplies and output it to the power management circuit, wherein the power management circuit includes a power sensing line connected to one of the plurality of input power supplies transmitted to the multiplexer, and determines the type of input power supply based on a signal received via the power sensing line. [Effects of the Invention]

[0012] As explained above, according to this embodiment, in a touch sensing circuit that receives two types of power inputs, even when the main power supply is not input, the touch operation can be maintained to function normally using the sub-power supply.

[0013] Furthermore, according to this embodiment, touch functionality and display functionality can be provided with a simpler circuit configuration, and the power consumed by the panel and touch sensing circuit can be reduced. [Brief explanation of the drawing]

[0014] [Figure 1] This figure shows the configuration of a touch sensing circuit according to one embodiment of the present invention. [Figure 2] This figure shows a touch sensing circuit configuration according to one embodiment of the present invention, from the perspective of the power supply circuit. [Figure 3] This is a first illustrative block diagram showing the signal flow of a touch sensing circuit according to one embodiment of the present invention. [Figure 4] This is a second illustrative block diagram showing the signal flow of a touch sensing circuit according to one embodiment of the present invention. [Figure 5] This is a timing diagram showing the input power supply change of a power management circuit according to one embodiment of the present invention. [Figure 6] This figure illustrates a method for determining the operating mode of a panel according to one embodiment of the present invention. [Figure 7] This figure illustrates a method for determining the operation of a power management circuit according to one embodiment of the present invention. [Figure 8] This figure illustrates a method for classifying the operating modes of a panel according to one embodiment of the present invention. [Modes for carrying out the invention]

[0015] Figure 1 shows the configuration of a touch sensing circuit according to one embodiment of the present invention.

[0016] Referring to FIG. 1, the display device 100 can include a panel 110, a source readout circuit (SRIC), a touch modulation circuit (TMIC) 121, a microcontroller (MCU) 122, a power management circuit (PMIC) 123, a gate driving circuit (GDIC) 130, a timing controller (TCON) 150, a host 160, and the like.

[0017] A plurality of data lines DL and a plurality of gate lines GL may be arranged on the panel 110, and a plurality of pixels (P) may be arranged. The pixel may be composed of a plurality of sub-pixels (SP).

[0018] The panel 110 can include both a common electrode and a touch electrode so as to implement a touch function and a display function, and one electrode may be divided to arrange the common electrode and the touch electrode. In the touch electrode, the touch or proximity of an object can be sensed using either a mutual capacitance method or a self-capacitance method.

[0019] <​​​​Furthermore, the source readout circuit 120 may include an internal readout circuit (ROIC: readout IC). The readout circuit may be integrated into the source readout circuit 120 together with the source driver circuit. The readout circuit can transmit a touch drive signal to the touch electrode around the subpixel (SP) via the touch line (TL) and receive touch sensing data, which is the amount of signal change at the touch electrode.

[0021] The touch modulation circuit 121 receives the output voltage of the power management circuit 123 and can synchronize and modulate the voltage transmitted to the source readout circuit 120 and the voltage transmitted to the level shifter (not shown) connected to the gate drive circuit 130 during the touch drive period.

[0022] The touch modulation circuit 121 can generate a zero-load driving signal (ZLD) to reduce the influence of parasitic electrostatics on the touch sensor on the sensing results, and transmit it to the panel and gate driving circuits 130. The zero-load driving signal (ZLD) can have the same phase as the driving signal that drives the touch sensor. When the zero-load driving signal (ZLD) is applied to both poles of the parasitic capacitor along with the driving signal, the amount of charge filling the parasitic capacitor becomes zero, and the parasitic electrostatics can be eliminated.

[0023] The microcontroller 122 is connected to the source readout circuit 120 and can send and receive data. The microcontroller 122 can send control data to the source readout circuit 120 to control the source readout circuit 120. The source readout circuit 120 can sense the touch or proximity of an external object from the touch sensor, generate touch sensing data, and send the touch sensing data to the microcontroller 122. The microcontroller 120 may be defined as a touch microcontroller (TMCU) or a touch control circuit.

[0024] The microcontroller 122 and the source readout circuit 120 can communicate based on either the SPI (serial peripheral interface) method or the I2C (inter-integrated circuit) method. In the SPI or I2C method, the communication entities can operate as master and slave, with the microcontroller 122 operating as the master and the source readout circuit 120 operating as the slave.

[0025] The power management circuit 123 can supply power to the panel 110, source readout circuit 120, touch modulation circuit 121, microcontroller 122, gate drive circuit 130, and timing controller 150. The power management circuit 123 can supply power by transmitting a drive voltage to each circuit via a power line, and the voltage applied to each circuit may be set individually according to the characteristics of the circuit. The power management circuit 123 can act as a power source for the internal circuits of the display device 100.

[0026] The power management circuit 123 can individually change and supply the voltage applied to each circuit depending on the type of power input from the host 160. The power management circuit 123 may include one or more booster circuits to increase the output voltage and one or more buck circuits to decrease the output voltage.

[0027] The gate drive circuit 130 can supply a gate drive signal of either turn-on voltage or turn-off voltage to the gate line GL. When a gate drive signal of turn-on voltage is supplied to a sub-pixel (SP), the sub-pixel (SP) is connected to the data line DL. When a gate drive signal of turn-off voltage is supplied to the sub-pixel (SP), the connection between the sub-pixel (SP) and the data line DL is released.

[0028] The timing controller 150 can receive video data, timing signals, etc., from the host 160 and can supply control signals to the gate drive circuit 130 and the touch control circuit 122. For example, the timing controller 150 can send a gate control signal to the gate drive circuit 130 to start scanning. The timing controller 150 can also output RGB video data to the microcontroller 122. Furthermore, the timing controller 150 can send a Data Control Signal (DCS) to the microcontroller 122 to control the source readout circuit 120 to supply data voltage to each subpixel (SP). In addition, the timing controller 150 can send a Touch Control Signal (TCS) to the microcontroller 122 to control the source readout circuit 120 to drive the touch electrodes of each subpixel (SP) to sense touch input.

[0029] The timing controller 150 receives a touch sync signal from the microcontroller 122 and can operate the source readout circuit 120 by dividing the time interval within a single frame into a display driving period and a touch driving period. The display driving period may be the period during which data voltage is transmitted to the subpixels of the panel 110, and the touch driving period may be the period during which touch driving voltage is transmitted to the subpixels of the panel 110.

[0030] The host 160 can supply one or more power sources to the power management circuit 123. The power management circuit 123 can generate drive voltages from the power sources received from the host 160 and supply these drive voltages to internal circuits of the display device 100, such as the panel 110, source readout circuit 120, microcontroller 122, touch modulation circuit 121, gate drive circuit 130, and timing controller 150. Therefore, the power sources that the host 160 supplies to the power management circuit 123 may be the sources of power supplied by the power management circuit 123.

[0031] When the host 160 supplies power to the power management circuit 123, the host 160 can supply power in two forms: a main power supply and a sub-power supply. The main power supply is for the circuits involved in the display of the display device 100, and the sub-power supply may be for the circuits involved in the touch sensing of the display device 10. The host 160 provides each power in the form of voltage and current, and the main power supply may have a main voltage V_D of approximately 5V and a display current of 2-3A. The sub-power supply may have a sub-voltage V_T of approximately 5V and a touch current of 0.5A or less. Because the power consumption of the display operation of the display device 100 is much higher than the power consumption of the touch operation, the display current may be higher than the touch current even if the voltage is the same.

[0032] Since the main power supply and the sub-power supply are provided in the form of voltage and current, the supply of the main power supply may, but is not limited to, the supply of the main voltage or the supply of the display current, and the supply of the sub-power supply may, but is not limited to, the supply of the sub-voltage or the supply of the touch current.

[0033] The power management circuit 123 processes the power received from the host 160 into voltages and currents suitable for each circuit, and can supply the processed power to each circuit. The main power supply may be processed to supply circuits involved in the display, such as the timing controller 150 and the gamma circuit, and the sub-power supply may be processed to supply circuits involved in touch sensing, such as the touch modulation circuit 121 and the microcontroller 122, but is not limited to this.

[0034] In the power management circuit 123, the signal levels of the drive voltage generated for display driving and the signal levels of the drive voltage generated for touch driving may be adjusted to be different, and the target to which the drive voltage generated by the power management circuit 123 is transmitted may also be changed depending on the driving mode. For example, the operation of the power management circuit 123 may be controlled by an internal control device (not shown) or by a control signal transmitted from the microcontroller 122. The power management circuit 123 can select whether or not to perform operation control based on a reference setting value stored in its internal memory.

[0035] In the display device 100, all or part of the circuit configuration for performing touch operations and display operations can be defined as a touch sensing circuit, and the circuit configuration for receiving power and supplying power to the inside of the display device 100 can be defined as a touch power supply circuit.

[0036] The internal circuit configuration of the display device 100 may be defined as a combination of all or part of conceptually separated circuit configurations. For example, the power supply circuit (not shown) may be defined as including all or part of the power management circuit 123 and including another circuit configuration.

[0037] Figure 2 shows a touch sensing circuit configuration according to one embodiment of the present invention, from the perspective of the power supply circuit.

[0038] Referring to Figure 2, the power management circuit 123 may include a first power supply circuit 123-1, a second power supply circuit 123-2, a third power supply circuit 123-3, a fourth power supply circuit 123-4, and so on.

[0039] The power management circuit 123 can be subdivided according to function, and can contain multiple power supply circuits 123-1 to 123-4 internally. The multiple power supply circuits 123-1 to 123-4 can receive the main power supply or sub-power supply, generate power, and supply that power to the internal circuits of the display device 100. The voltages generated to supply power by the multiple power supply circuits 123-1 to 123-4 can be classified and defined as a first drive voltage, second drive voltage, third drive voltage, fourth drive voltage, etc.

[0040] Some of the multiple power supply circuits 123-1 to 123-4 can drive a combined circuit formed by integrating both a display circuit and a touch circuit. Here, the display circuit can include circuits involved in the display operation of the display device 100 that outputs video data via pixels, and the touch circuit can include circuits involved in the touch operation of the display device 100 that senses the touch or proximity of an external object via touch electrodes.

[0041] For example, the display circuit may include a gamma circuit 170 that generates a gamma voltage corresponding to the grayscale value in order to generate data voltages corresponding to the RGB video data, a source driver circuit within a source readout circuit 120 that outputs the data voltage, and a timing controller 150 that controls the source driver to supply the RGB video data. The touch circuit may include a touch modulation circuit 121 that generates a touch drive voltage VCOM_M for driving the touch electrodes, and a microcontroller 122 that controls the readout circuit included in the source readout circuit 120, receives touch data, and calculates touch coordinates.

[0042] While display circuits and touch circuits are involved in either display operation or touch sensing operation, a coupling circuit can be involved in both display operation and touch sensing operation. A coupling circuit can have a configuration in which both the display circuit and the touch circuit are integrated. For example, a coupling circuit may include a Source Readout Integrated Circuit (SRIC) 120 in which both the source driver circuit and the readout circuit are integrated.

[0043] The first power supply circuit 123-1 can generate a display analog voltage AVDD_D to drive the source readout circuit 120. The first power supply circuit 123-1 supplies power by generating an analog voltage (AVDD), and in particular, it can generate an analog voltage from the main voltage V_D. The display analog voltage AVDD_D can mean the analog voltage generated based on the main voltage V_D. If necessary, the analog voltage (AVDD) generated by the first power supply circuit 123-1 may be defined as the first voltage.

[0044] The first power supply circuit 123-1 can generate a common voltage VCOM to drive the touch modulation circuit 121. The touch modulation circuit 121 can generate a touch drive voltage VCOM_M for driving the touch electrodes from the common voltage VCOM. The touch modulation circuit 121 can transmit the touch drive voltage VCOM_M to the source readout circuit 120.

[0045] The second power supply circuit 123-2 can convert the power received from the host 160 and supply power to the microcontroller 122. The second power supply circuit 123-2 may include a step-down converter or buck converter that converts the output voltage to a lower voltage than the input voltage. For example, the second power supply circuit 123-2 can receive a signal with a sub-power voltage of 5V and convert it to a signal with another voltage such as 1.8V or 3.3V. The second power supply circuit 123-2 can transmit the converted voltage to the microcontroller unit (MCU) 122.

[0046] The third power supply circuit 123-3 can convert the power received from the host 160 and supply power to the gamma circuit 170. The third power supply circuit 123-3 may include a buck converter (BUCK). The third power supply circuit 123-3 can convert the main voltage V_D from the host 160 and drive the gamma circuit 170 with the converted voltage.

[0047] The fourth power supply circuit 123-4 can convert the power received from the host 160 and supply power to the timing controller 150. The fourth power supply circuit 123-4 may include a buck converter BUCK. The fourth power supply circuit 123-4 can convert the main voltage V_D from the host 160 and drive the timing controller 150 with the converted voltage.

[0048] The source readout circuit 120 can operate with the drive voltage transmitted from the first power supply circuit 123-1. The source readout circuit 120 can receive the display analog voltage AVDD_D and activate its internal circuitry. The source driver circuit and readout circuit integrated together with the source readout circuit 120 can operate using the display analog voltage AVDD_D as power.

[0049] The touch modulation circuit 121 can provide a drive voltage to the source readout circuit 120. The touch modulation circuit 121 can receive a common voltage VCOM from the first power supply circuit 123-1 and generate a touch drive voltage VCOM_M to drive the touch electrode. The touch modulation circuit 121 can also receive a gate low voltage (VGL) and a gate high voltage (VGH) from a power supply circuit (not shown) and generate a modulation gate low voltage (VGL_M) to be applied to the touch electrode.

[0050] The timing controller 150 can operate by receiving power from the fourth power supply circuit 123-4. The timing controller 150 can control the source readout circuit 120 by transmitting control signal DCS and video data RGB.

[0051] The gamma circuit 170 can generate a gamma voltage by receiving power from the third power supply circuit 123-3. The gamma circuit 170 can also receive the display analog voltage AVDD_D from the first power supply circuit 123-1. The amplifier of the gamma circuit 170 may receive a voltage from the third power supply circuit 123-3 via its input terminal and the display analog voltage AVDD_D via its bias terminal. The amplifier can generate a gamma voltage from the voltage of the third power supply circuit 123-3 and the display analog voltage AVDD_D.

[0052] The host 160 can supply main or sub-power to the power management circuit 123 via power lines, and each power supply may be transmitted to multiple power supply circuits 123-1 to 123-4 inside the power management circuit 123. The host 160 is not limited in type as long as it can be powered via an interface.

[0053] For example, the main voltage V_D may be supplied to the first power supply circuit 123-1, the third power supply circuit 123-3, and the fourth power supply circuit 123-4 via the first power supply line, and the sub-voltage V_T may be supplied to the second power supply circuit 123-2 via the second power supply line. The first power supply circuit 123-1, the third power supply circuit 123-3, and the fourth power supply circuit 123-4 can then convert the input main power supply to generate various forms of power signals. The second power supply circuit 123-2 can then convert the input sub-power supply to generate various forms of power signals.

[0054] The display device 100 can operate in normal mode, display mode, or sleep mode.

[0055] Normal mode is defined as the state in which the display device 100 performs both display driving and touch driving, display mode is defined as the state in which only display driving is performed and touch driving is not performed, and sleep mode is defined as the state in which only touch sensing is performed and display driving is not performed. Of the operating modes of the display device, in normal mode both the display circuit and the touch circuit are operating, in display mode only the display circuit is operating and the touch circuit is not operating, and in sleep mode only the touch circuit is operating and the display circuit is not operating.

[0056] Each driving mode of the display device can be implemented by interrupting the power supply to the display circuit and touch circuit. For example, in normal mode, the host 160 can provide both the main voltage V_D and the sub-voltage V_T; in display mode, the host 160 can provide only the main voltage V_D; and in sleep mode, the host 160 can provide only the sub-voltage V_T.

[0057] If the main voltage V_D and sub-voltage V_T are supplied separately depending on the drive mode of the display device, it will be impossible to supply adequate power to the coupling circuit, which includes both the display circuit and the touch circuit. In particular, if the coupling circuit receives only one input voltage as its source, and this source voltage is interrupted depending on the mode, the operation of some circuits in the coupling circuit will be restricted.

[0058] For example, the source readout circuit 120, which includes a source driver circuit and a readout circuit, can receive power only from the first power supply circuit 123-1, specifically the display analog voltage AVDD_D based on the main voltage V_D. If the display device 100 operates in sleep mode, the main voltage V_D is cut off, and circuits driven by the main voltage V_D may be turned off. The circuits that are turned off may include display circuits such as the timing controller 150 and the gamma circuit 170, as well as circuits that supply power to the display circuits, such as the first power supply circuit 123-1. However, coupling circuits including the display circuit and the touch circuit may also be turned off. In this case, the readout circuit must perform touch driving even in sleep mode, but since it is not supplied with power, touch sensing may not function correctly in sleep mode.

[0059] The power supply circuit 123 according to one embodiment may have its internal circuit configuration modified or may include a different circuit configuration in order to maintain that touch sensing can be performed regardless of the driving mode of the display device and to reduce power consumption.

[0060] Figure 3 is a first illustrative block diagram showing the signal flow of a touch sensing circuit according to one embodiment of the present invention.

[0061] Referring to Figure 3, the display device 200 may include a source readout circuit 220, a touch modulation circuit 221, a microcontroller 222, a first power supply circuit 223, a second power supply circuit 224, a multiplexer 225, a gate drive circuit 230, a level shifter 231, a timing controller 250, and the like.

[0062] The source readout circuit 220, touch modulation circuit 221, microcontroller 222, first power supply circuit 223, second power supply circuit 224, multiplexer 225, gate drive circuit 230, level shifter 231, and timing controller 250 may include the circuit configurations and functions of Figures 1 and 2 described above, and may include embodiments that can be modified by an ordinary technician.

[0063] The multiplexer 225 can receive a first voltage (e.g., main voltage V_D) transmitted via a first power line and a second voltage (e.g., sub voltage V_T) transmitted via a second power line. The first and second voltages may be of the same magnitude, but voltages of different magnitudes may be transmitted to the multiplexer 225 as needed.

[0064] The multiplexer 225 can select and output one of several input analog signals, and may be controlled whether or not it operates, the timing of its operation, and the type of signal to be selected and output, according to a control signal from the timing controller 250 or the microprocessor 222.

[0065] Furthermore, if necessary, the multiplexer 225 may, by means of an internal arithmetic unit (not shown), determine which signal to output based on the type and number of input signals, without receiving any other control signals from an external source. For example, the internal arithmetic unit (not shown) can set a criterion to select and output the first voltage when both the first and second voltages are transmitted to the multiplexer 225, and can perform further calculations to determine the type of input signal, taking into account the input signal strength, timing, input port location, etc., when only one of the first or second voltages is transmitted.

[0066] Furthermore, the multiplexer 225 can also determine the output signal based on predefined criteria (for example, the presence or absence of a main power supply or sub-power supply input) without performing any additional calculations.

[0067] The multiplexer 225 can independently change the type of voltage selected according to the panel's driving mode. The panel's driving modes may be divided into normal mode, display mode, and sleep mode. In normal mode, both the main power and sub-power are supplied to the multiplexer 225. In display mode, the main power is supplied to the multiplexer 225, but the sub-power is not. In sleep mode, the sub-power is supplied to the multiplexer 225, but the main power may not be supplied.

[0068] For example, if both the main power supply and the sub-power supply are input to the multiplexer 225, the multiplexer 225 or the switch circuit inside the multiplexer 225 can select one of the power supplies. The multiplexer 225 can prioritize the main power supply for a more stable power supply and transmit it to the connected first power supply circuit 223. In this case, the display can be driven via the first power supply circuit 223, and the touch can be driven via the second power supply circuit 224. The second power supply circuit 224 is connected via a second power supply line connected to the input terminal of the multiplexer 225, enabling a stable power supply that is not affected by whether or not the display is driven.

[0069] As another example, if only the main power is input to the multiplexer 225, the multiplexer 225 or the switch circuit inside the multiplexer 225 can transmit the main power to the first power supply circuit 223. In this case, the main power is transmitted to the first power supply circuit 223 and only the display operation is performed, the sub-power is not transmitted to the second power supply circuit 224, and the line transmitting the sub-power is separated from the line transmitting the main power, so the display device does not need to perform touch operation.

[0070] As another example, if only the sub-power supply is input to the multiplexer 225, the multiplexer 225 or the switch circuit inside the multiplexer 225 can transmit the sub-power supply to the first power supply circuit 223. In this case, the sub-power supply is transmitted to the first power supply circuit 223 to supply power to the touch modulation circuit 221 and the source readout circuit 220, and the sub-power supply is transmitted to the second power supply circuit 224 to perform touch operation. The display circuit and the touch circuit may be kept connected rather than separated so that the sub-power supply can be transmitted to the first power supply circuit 223.

[0071] When the main power supply and sub-power supply are transmitted to the first power supply circuit 223 via the multiplexer 225, the continuity of the power supply can be maintained, improving the problems of power supply instability that occurred in conventional touch sensing circuits due to the separation of power supplies to the touch circuit and the display circuit, as well as the problem of power oversupply that occurred because the power supplies were not separated.

[0072] Furthermore, since the multiplexer 225 alone can easily output multiple input power supplies, the power consumed for calculations by the microprocessor 222 and the timing controller 250 can be reduced.

[0073] The first power supply circuit 223 can distinguish and recognize the main voltage V_D and the sub-voltage V_T, and can sense and determine whether the main voltage V_D supplied to the first power supply line is ON or OFF. For example, if voltages of the same magnitude are supplied as the main voltage V_D and the sub-voltage V_T, the first power supply circuit 223 can form a separate sensing line between the first power supply circuit 223 and the first power supply line in order to determine which voltage is the main voltage V_D.

[0074] The first power supply circuit 223 may include an internally operable circuit configuration to determine the state of the main voltage V_D (e.g., the magnitude of the main voltage V_D, the presence or absence of an input, the input timing, the signal waveform, etc.).

[0075] When the main power supply is ON, the first power supply circuit 223 can transmit drive voltages to the gate drive circuit 230, level shifter 231, timing controller 250, source readout circuit 220, and touch modulation circuit 221. Depending on the target of the voltage transmitted to each circuit configuration, it can selectively control the operation by dividing it into a first drive voltage or a second drive voltage. For example, the first drive voltage may be a drive voltage transmitted to one or more of the gate drive circuit 230, level shifter 231, and timing controller 250, and the second drive voltage may be a drive voltage transmitted to one or more of the source readout circuit 220 and touch modulation circuit 221. When the main power supply is OFF, the first power supply circuit 223 can reduce power consumption by turning off the power supply (e.g., the first drive voltage) transmitted to the gate drive circuit 230, level shifter 231, and timing controller 250. In this case, the first power supply circuit 223 can reduce power consumption by supplying power (e.g., a second drive voltage) only to the source readout circuit 220 and the touch modulation circuit 221. The first power supply circuit 223 can sense the on / off state of the main power supply and change its operation to output drive signals with different signal levels, thereby more effectively reducing the power consumption used for touch driving.

[0076] When the main power supply of the first power supply circuit 223 is ON, the display screen can be reliably output regardless of whether or not the sub-power supply is input, and the display screen does not need to be output only when the main power supply is OFF.

[0077] The first drive voltage and the second drive voltage refer to the drive voltages transmitted from the first power supply circuit 223. The type of drive voltage may be defined by the object to which the voltage is transmitted, or it may be defined by the timing at which the voltage is transmitted.

[0078] The drive voltage of the first power supply circuit 223 may be controlled by an internal arithmetic unit (not shown), or it may be controlled by a microprocessor 222. Furthermore, the state of the drive voltage generated by the first power supply circuit 223 may be individually defined by conditions stored in an internal memory (not shown). For example, the criteria stored in the memory (not shown) may be the magnitude of the drive voltage, a criterion for changing the waveform, or a criterion for determining the on / off state of the drive voltage.

[0079] All or part of the first and second drive voltages may be transmitted from the first power supply circuit 223 simultaneously or at different times, and the order or method of supplying the drive voltages may be defined in a manner different from that described above by the operation based on the calculation results of the first power supply circuit 223. The second power supply circuit 224 can supply power to the microprocessor 222 to maintain the touch operation. To reduce the power consumption of the microprocessor 222, the second power supply circuit 224 may include one or more buck converters. The buck converters can change the input sub-voltage to a lower voltage and maintain it at a voltage suitable for driving the microprocessor 222.

[0080] Since the second power supply circuit 224 can directly receive the sub-voltage via a second power supply line connected to the input terminal rather than the output terminal of the multiplexer, it is possible to prevent power loss that occurs when the power is supplied indirectly through the multiplexer 225 and the first power supply circuit 223, and the power supplied to the display circuit by the first power supply circuit 223 and the power supplied to the touch circuit by the second power supply circuit 224 can be managed and controlled independently.

[0081] In an in-cell system that implements touch operation and display operation on a single panel, the touch operation and display operation are not electrically separated and share the same circuit configuration. Therefore, in one embodiment, the power supply circuit electrically separates the first power supply circuit and the second power supply circuit, enabling stable implementation of touch operation and display operation.

[0082] The microprocessor 222 or timing controller 250 can generate a control signal to the multiplexer 225 that selects and outputs the main voltage when both the main voltage and the sub-voltage are input to the multiplexer 225, and transmit this signal to the multiplexer 225.

[0083] The microphone processor 222 can generate a control signal to adjust the output voltage of the first power supply circuit 223 and transmit it to the first power supply circuit 223.

[0084] The touch modulation circuit 221 receives the output voltage of the first power supply circuit and, during the touch drive period, synchronizes and modulates the voltage transmitted to the source readout circuit 220 and the voltage transmitted to the level shifter 231 connected to the gate drive circuit 230. In this case, the operation of the source readout circuit 220 and the gate drive circuit 230 can be operated simultaneously or in conjunction with each other to have a fixed temporal coupling relationship.

[0085] Figure 4 is a second illustrative block diagram showing the signal flow of a touch sensing circuit according to one embodiment of the present invention.

[0086] Referring to Figure 4, the first power supply circuit 223 and the second power supply circuit 224 described above can be integrated into a single power management circuit 226.

[0087] The touch operation control that was implemented in the second power supply circuit 224 in Figure 3 can be implemented in the logic circuit inside the power management circuit 226.

[0088] The power management circuit 226, through its internal arithmetic processing circuit, can sense the presence or absence of input for the main voltage V_D and sub-voltage V_T, separately from the control signals of the microprocessor 222. If only the main voltage V_D is input, it can drive the source readout circuit 220, touch modulation circuit 221, gate drive circuit 230, level shifter 231, and timing controller 250 to perform display operation. Furthermore, the integrated power management circuit 226 can transmit the voltage to drive the microcontroller 222, enabling touch operation as well.

[0089] The multiplexer 225 can prioritize supplying the main voltage V_D to the power management circuit 226 when both the main voltage V_D and the sub-voltage V_T are input. The timing controller 250 can transmit information about the panel's drive mode to the multiplexer 225 on a time interval basis and change its output in conjunction with the operation of the power management circuit 226.

[0090] If only the sub-voltage V_T is input to the multiplexer 225, it can output the sub-voltage V_T and supply it to the power management circuit 226. The power management circuit 226 senses that the main power supply V_D has been turned off and can change or maintain the power supply of the gate drive circuit 230, level shifter 231, and timing controller 250 to off. In this case, the power management circuit 226 can change or maintain the power supply of the source readout circuit 220, touch modulation circuit 221, and microprocessor 222 to on. The overall power consumption of the display device 200 can be reduced by keeping the display-related circuits in the off state.

[0091] Figure 5 is a timing diagram showing the input power supply change of a power management circuit according to one embodiment of the present invention.

[0092] Referring to Figure 5, the type of power supply transmitted to the power management circuit may be changed depending on the time interval.

[0093] A multiplexer (not shown) may be connected to the front of a power management circuit (not shown) to select one of several input power supplies transmitted from an external system, and the main voltage V_D may be transmitted in the first time interval t1.

[0094] A power management circuit (not shown) or a touch control circuit (not shown) can monitor the type of input power supply for each time interval, and if the input power supply does not change, it can maintain the state of the previous time interval. If the state of the input power supply being monitored (e.g., the main power supply) changes, the multiplexer (not shown) can change the input power supply transmitted to the power management circuit.

[0095] In the second time interval t2, the sub-voltage V_T may be selected as the output voltage of a multiplexer (not shown) and transmitted to the power management circuit. Input power monitoring can be performed in the second time interval t2 as in the first time interval t1.

[0096] In the third time interval t3, the main voltage V_D may be selected as the output voltage of a multiplexer (not shown) and transmitted to the power management circuit.

[0097] In the first time interval t1 to the third time interval t3, the multiplexer may operate as shown in Figures 1 to 4 above.

[0098] Figure 6 illustrates a method for determining the operating mode of a panel according to one embodiment of the present invention.

[0099] Referring to Figure 6, the method 1000 for determining the operating mode of the panel may include steps such as determining the type of power input (S1001), determining whether or not to drive the display (S1003), determining whether or not to drive the touch (S1005), and determining the driving mode of the panel (S1007), and the order of each step may be changed.

[0100] The step of determining the type of power input (S1001) can determine the type and state of the power supply (e.g., voltage and current intensity) transmitted to a power management circuit (not shown) or a multiplexer (not shown). For example, the power management circuit (not shown) can determine whether or not there is an input of a first voltage transmitted through a first power line.

[0101] In the step of determining whether or not to drive the display (S1003), the decision can be made based on the type and state of the power supply (e.g., voltage and current intensity) transmitted to the power management circuit (not shown) or multiplexer (not shown). The power management circuit (not shown) can separately set whether or not to drive the display depending on whether only the main power supply is input, whether only the sub-power supply is input, or whether both the main power supply and sub-power supply are input simultaneously. For example, the display can be driven when the main power supply is transmitted to the power management circuit (not shown) or multiplexer (not shown).

[0102] The step of determining whether or not to perform touch operation (S1005) involves determining whether or not a sub-power supply is input, and then deciding whether or not to perform touch operation. The power management circuit (not shown) can perform touch operation when a sub-power supply is input.

[0103] In the step of determining the operating mode of the panel (S1007), the panel's drive mode (e.g., normal mode, display mode, sleep mode) can be set by the type and state of the power supply transmitted to the power management circuit (not shown) or multiplexer (not shown). The panel's drive mode may be defined by the type of input power supply, but the order may be changed, and the type of input power supply may be adjusted to differ depending on the panel's drive mode.

[0104] Figure 7 illustrates a method for determining the operation of a power management circuit according to one embodiment of the present invention.

[0105] Referring to Figure 7, the method 1100 for determining the operation of the power management circuit may include steps such as determining the type of power input (S1101), generating a multiplexer control signal (S1103), selecting the input power supply for the power management circuit (S1105), and driving the power management circuit (S1107).

[0106] The step of determining the type of power supply input (S1101) may be the step of determining the type of power supply (e.g., main power supply and sub-power supply) that is input to the multiplexer (not shown).

[0107] The step of generating a multiplexer control signal (S1103) may be a step of generating a signal to control the operation of the multiplexer by a microprocessor (not shown) or a timing controller (not shown).

[0108] The step of selecting the input power supply for the power management circuit (S1105) may be the step of controlling the output voltage of the multiplexer in accordance with the multiplexer operation control signal from the microprocessor (not shown) or timing controller (not shown) described above, and transmitting said output voltage to the power management circuit.

[0109] The step of driving the power management circuit (S1107) may be a step in which the power supplied to the connected source readout circuit, touch modulation circuit, level shifter, timing controller, microprocessor, etc. is turned on (ON), turned off (OFF), or driven by changing the voltage phase or timing, depending on the type and state of the power supply being input.

[0110] Figure 8 illustrates a method for classifying the operating modes of a panel according to one embodiment of the present invention.

[0111] Referring to Figure 8, the method 1200 for classifying the panel drive mode may include steps such as receiving input power (S1201), determining whether or not there is input from the main power supply (S1202), and determining whether or not there is input from the sub-power supply (S1203), and may be calculations performed by a touch power supply circuit (not shown) or a microprocessor (not shown).

[0112] The step of receiving input power (S1201) may be a step of receiving multiple input power supplies via multiple power lines. One or more buck circuits, one or more power management circuits, and one or more multiplexers can be connected sequentially or in parallel to receive input power.

[0113] The step of determining whether or not there is a main power input (S1202) may be a step in which the presence or absence of a main power signal transmitted to a power management circuit (not shown) or a multiplexer (not shown) is determined, and if no main power is input, the panel's drive mode is set to sleep mode.

[0114] The step of determining whether or not a sub-power supply is being input (S1203) involves determining whether or not a sub-power supply is being transmitted to a power management circuit (not shown) or a multiplexer (not shown). If no sub-power supply is being input, the step may be to set the panel's drive mode to display mode. If a sub-power supply is being input, it can be determined that the system is in normal mode.

[0115] The step of determining whether or not the sub-power supply is being input (S1203) can only be performed if the main power supply is being input, but the order in which the main power supply input is determined and the sub-power supply input is determined is not limited to this.

[0116] The display mode (S1204) may be configured so that only display operations occur on the panel, and touch operations are not performed.

[0117] The normal mode (S1205) may be one in which the panel operates in a way that allows for both display operation and touch operation.

[0118] Sleep mode (S1206) may be a mode in which the panel only allows touch input and no display operation occurs.

[0119] Information regarding the display mode (S1204), normal mode (S1205), and sleep mode (S1206) may be stored in a microprocessor (not shown) or a timing controller (not shown) and used to control the operation of each circuit or the operation of the power input. [Explanation of Symbols]

[0120] 100, 200…Display device, 110…Panel, 120, 220…Source readout circuit, 121…Touch modulation circuit, 122, 222…Microcontroller, 123…Power management circuit, 130, 230…Gate drive circuit, 150, 250…Timing controller, 160…Host, 223…First power supply circuit, 224…Second power supply circuit, 225…Multiplexer, 231…Level shifter.

Claims

1. A multiplexer connected to a first power line and a second power line, which selects and outputs either a first voltage supplied via the first power line or a second voltage supplied via the second power line, A first power supply circuit generates a first drive voltage and a second drive voltage using the voltage supplied from the multiplexer, recognizes the presence or absence of the first voltage supplied via the first power supply line, and if the first voltage is not recognized, does not output the first drive voltage. The circuit includes a second power supply circuit connected to the second power supply line and which modifies the voltage transmitted to the microcontroller (MCU), The panel's operating modes include normal mode, display mode, and sleep mode. In the normal mode, the first voltage is input to the multiplexer via the first power line, and the second voltage is input to the multiplexer and the second power circuit via the second power line. In the display mode, the first voltage is input to the multiplexer via the first power line, but the second voltage is not input to the multiplexer and the second power circuit via the second power line. In the sleep mode, the second voltage is input to the multiplexer and the second power supply circuit via the second power supply line, but the first voltage is not input to the multiplexer via the first power supply line in the power supply circuit.

2. The second power line connected to the second power circuit is connected to the input terminal of the multiplexer. The power supply circuit according to claim 1, wherein the second power supply circuit includes a buck converter that changes the output voltage to a level lower than the voltage of the input signal.

3. The power supply circuit according to claim 1, wherein the first power supply circuit transmits a display drive voltage to a source readout circuit when the first voltage is input.

4. The power supply circuit according to claim 1, wherein the first power supply circuit transmits a touch drive voltage of a different magnitude from the display drive voltage to the source readout circuit when the second voltage is input.

5. The power supply circuit according to claim 1, further comprising a touch modulation circuit that receives the output voltage of the first power supply circuit and synchronizes and modulates the voltage transmitted to the source readout circuit and the voltage transmitted to the level shifter connected to the gate drive circuit during the touch drive period.

6. The system further includes a touch control circuit that generates signals to control the multiplexer, The power supply circuit according to claim 1, wherein the touch control circuit generates a multiplexer control signal that selects the first voltage and outputs it to the first power supply circuit when both the first voltage and the second voltage are input to the multiplexer.

7. The power supply circuit according to claim 1, further comprising an internal arithmetic unit that generates a control signal for selecting either the first voltage or the second voltage based on a pre-set criterion.

8. A multiplexer connected to the first line to receive the main voltage and connected to the second line to receive the sub-voltage, A power management circuit receives a voltage output by the multiplexer, which selects either the main voltage or the sub-voltage, and determines whether or not the main voltage is input. A touch modulation circuit connected to the power management circuit on the panel modulates the signal transmitted to the touch electrode, The system includes a buck converter connected to the second line to reduce the level of the sub-voltage and transmit the reduced sub-voltage to a microcontroller, The multiplexer changes the type of voltage selected depending on the driving mode of the panel. The driving modes of the panel include normal mode, display mode and sleep mode. In the normal mode, the main voltage is input to the multiplexer via the first line, and the sub-voltage is input to the multiplexer and the buck converter via the second line. In the display mode, the main voltage is input to the multiplexer via the first line, but the sub-voltage is not input to the multiplexer and the buck converter via the second line. In the sleep mode, the sub-voltage is input to the multiplexer and the buck converter via the second line, but the main voltage is not input to the multiplexer via the first line, in a touch sensing circuit.

9. The touch sensing circuit according to claim 8, further comprising a level shifter that receives a voltage from the touch modulation circuit or the power management circuit and adjusts the voltage level transmitted to the gate drive circuit.

10. The touch sensing circuit according to claim 8, further comprising a touch control circuit connected to the power management circuit and controlling the operation of the power management circuit or the multiplexer.

11. The aforementioned power management circuit is Determine whether or not the main voltage or sub-voltage is input. The touch sensing circuit according to claim 8, wherein when the main voltage is input, a common voltage for generating display operation is transmitted to the source readout circuit, and when the sub voltage is input, a touch drive voltage for generating touch operation is transmitted to the source readout circuit.

12. One or more buck converters connected to a second power line to receive a sub-power supply and converting the output voltage to a level lower than the input voltage, One or more power management circuits that generate voltage and transmit it to a source readout circuit or touch modulation circuit, It includes one or more multiplexers connected to a first power line to receive the main power supply, and which select one of the main power supply and the sub-power supply and output it to the power management circuit, The power management circuit includes a power sensing line connected to one of a plurality of input power supplies transmitted to the multiplexer, and determines the type of input power supply based on the signal received via the power sensing line. The panel's operating modes include normal mode, display mode, and sleep mode. In the normal mode, the main power supply is input to the multiplexer via the first power line, and the sub-power supply is input to the multiplexer and the buck converter via the second power line. In the display mode, the main power supply is input to the multiplexer via the first power line, but the sub-power supply is not input to the multiplexer and the buck converter via the second power line. In the sleep mode, the sub-power supply is input to the multiplexer and the buck converter via the second power supply line, but the main power supply is not input to the multiplexer via the first power supply line, in a touch sensing circuit.

13. The touch sensing circuit according to claim 12, wherein one or more buck converters receive one of the plurality of input power supplies and generate and transmit a drive voltage for the touch control circuit.

14. The touch sensing circuit according to claim 12, further comprising a timing controller connected to the power management circuit and transmitting information regarding the panel's drive mode to the power management circuit for each time interval.

15. The touch sensing circuit according to claim 12, wherein the power management circuit supplies power to the source readout circuit and the touch modulation circuit according to the state of the main power supply.

16. The touch sensing circuit according to claim 12, wherein the power management circuit outputs a voltage for driving the display when the main power is input, and outputs a voltage for driving the touch when the sub power is input.

17. The touch sensing circuit according to claim 12, wherein the input power received via the power sensing line includes the main power supply, and the operation of the multiplexer is linked to the operation of the power management circuit.

Images