Display apparatus, electronic apparatus including the same, and method of operating the display apparatus

Abstract

A display device, an electronic device including the same, and a method of operating the display device are provided. The display device can include a display panel; and a voltage generator to supply a panel power voltage to the display panel based on an input voltage. The voltage generator can control an output level of the panel power voltage by switching an operation mode thereof between a low power mode and a normal mode based on a size of a load current relative to a threshold current. The voltage generator controls a voltage level of the panel power voltage. The threshold current increases as an absolute value of the panel power voltage decreases. When the absolute value of the panel power voltage becomes lower than an absolute value of a reference power voltage, the threshold current is instantaneously decreased to reduce a threshold current difference between the low power mode and the normal mode, thereby suppressing occurrence of flicker on the display panel.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2025-0057256, filed on April 30, 2025, with the Korean Intellectual Property Office (KIPO), the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] Embodiments of the present invention relate to a display device, an electronic device including the display device, and a method of operating the display device. More specifically, embodiments of the present invention relate to a display device operating in a low-power mode or a normal mode, an electronic device including the display device, and a method of operating the display device. Background Technology

[0004] The display device may include a display panel and a display panel driver. The display panel includes multiple gate lines, multiple data lines, multiple transmit lines, and multiple pixels. The display panel driver includes a gate driver that provides gate signals to the gate lines, a data driver that provides data voltages to the data lines, a transmit driver that provides transmit signals to the transmit lines, and a drive controller that controls the gate driver, data driver, and transmit driver.

[0005] The display device may further include a voltage generator. The voltage generator can use an input voltage to generate a panel power voltage and apply the panel power voltage to the display panel. The display panel can use the panel power voltage to display an image.

[0006] The voltage generator can operate in either a low-power mode or a normal mode based on the load current (i.e., the panel current), where the operating mode is determined by whether the load current exceeds a threshold current. For example, the voltage generator can operate in low-power mode when the load current is less than the threshold current, and in normal mode when the load current is greater than the threshold current. The low-power mode can be pulse skip mode (PSM). When the voltage generator operates in pulse skip mode, the switching of the switching elements included in the voltage generator can be skipped, thereby reducing the overall switching frequency and decreasing the power consumption due to the switching of the switching elements.

[0007] By setting a larger threshold current, the switching skip frequency can be increased, and the power consumption of the voltage generator can be further reduced. However, as the switching skip frequency of the switching elements increases, the ripple of the panel power voltage may also increase, causing fluctuations in the image brightness of the display panel, and these fluctuations may be perceived as flicker. Therefore, flicker in the displayed image can degrade the display quality of the display device.

[0008] Accordingly, it may be important to control the threshold current in order to suppress flickering in the image while minimizing the power consumption of the voltage generator. Summary of the Invention

[0009] An embodiment of the present invention provides a display device for controlling a threshold current to suppress flicker and reduce power consumption in a low-power mode.

[0010] An embodiment of the present invention provides an electronic device including the display device and a method for operating the display device.

[0011] According to an embodiment, the display device may include: a display panel including pixel circuitry; and a voltage generator configured to generate a panel power voltage based on an input voltage and supply the panel power voltage to the display panel. The voltage generator is configured to control the output level of the panel power voltage by switching an operating mode of the voltage generator based on the magnitude of the load current relative to a threshold current. When the absolute value of the panel power voltage is greater than the absolute value of a reference power voltage, as the absolute value of the panel power voltage decreases from a first absolute value to a second absolute value, the threshold current correspondingly increases from a first threshold current to a second threshold current. When the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, as the absolute value of the panel power voltage decreases from a third absolute value to a fourth absolute value, the threshold current increases from a third threshold current to a fourth threshold current. The voltage generator is configured to control the third threshold current at the third absolute value of the panel power voltage to be less than the second threshold current at the second absolute value of the panel power voltage.

[0012] In one embodiment, the voltage generator is configured to operate in a low-power mode when the load current is less than a threshold current and in a normal mode when the load current is greater than the threshold current.

[0013] In an embodiment, the switching frequency of the switching element included in the voltage generator in low-power mode is lower than the switching frequency of the switching element in normal mode.

[0014] In this embodiment, when the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, the threshold current increases as the absolute value of the panel power voltage decreases, and when the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, the threshold current increases as the absolute value of the panel power voltage decreases.

[0015] In one embodiment, the voltage generator includes: a first controller configured to control the output of a control power voltage based on a pulse skip control signal; an amplifier configured to output a pulse skip control signal based on a pulse skip reference voltage; and a second controller configured to control the pulse skip reference voltage based on a threshold current.

[0016] In an embodiment, the second controller may include: a multiplexer configured to output set threshold current data or reference threshold current data based on a selection signal; and a reference voltage generator configured to output a pulse skip reference voltage based on one of the set threshold current data and the reference threshold current data.

[0017] In one embodiment, the second controller further includes a logic gate that outputs a selection signal based on reference power voltage data and the power voltage data.

[0018] In this embodiment, when the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, the power voltage data has a logic high level, and the selection signal has a logic high level, causing the multiplexer to output the reference threshold current data as a pulse to skip the reference voltage.

[0019] In this embodiment, when the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, the power voltage data has a logic low level, and the selection signal has a logic low level, causing the multiplexer to output the set threshold current data as a pulse to skip the reference voltage.

[0020] In an embodiment, the multiplexer may include a first terminal for receiving set threshold current data, a second terminal for receiving reference threshold current data, a third terminal for receiving a selection signal, and an output terminal for outputting one of the set threshold current data and the reference threshold current data, wherein the logic gate includes a first terminal for receiving reference power voltage data, a second terminal for receiving power voltage data, and an output terminal for outputting the selection signal.

[0021] In this embodiment, the logic gate is an AND gate configured to perform a logical AND operation between the reference power voltage data and the power voltage data.

[0022] According to an embodiment, the electronic device may include: a display panel including pixel circuitry; a display panel driver configured to control the display panel based on an input control signal; and a processor configured to output the input control signal. The display panel driver includes a voltage generator configured to apply a panel power voltage to the display panel based on an input voltage. The voltage generator is configured to control the output level of the panel power voltage by switching an operating mode of the voltage generator based on the magnitude of the load current relative to a threshold current. When the absolute value of the panel power voltage is greater than the absolute value of a reference power voltage, as the absolute value of the panel power voltage decreases from a first absolute value to a second absolute value, the threshold current correspondingly increases from a first threshold current to a second threshold current. When the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, as the absolute value of the panel power voltage decreases from a third absolute value to a fourth absolute value, the threshold current increases from a third threshold current to a fourth threshold current. The voltage generator is configured to control the third threshold current at the third absolute value of the panel power voltage to be less than the second threshold current at the second absolute value of the panel power voltage.

[0023] In an embodiment, the voltage generator is configured to operate in a low-power mode when the load current is less than a threshold current and in a normal mode when the load current is greater than the threshold current, and the switching frequency of the switching element included in the voltage generator in the low-power mode is less than the switching frequency of the switching element in the normal mode.

[0024] In this embodiment, when the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, the threshold current increases as the absolute value of the panel power voltage decreases; when the absolute value of the panel power voltage becomes lower than the reference power voltage, the threshold current decreases instantaneously; and when the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, the threshold current increases as the absolute value of the panel power voltage decreases.

[0025] In an embodiment, the voltage generator may include: a first controller configured to control the output of the control power voltage based on a pulse skip control signal; an amplifier configured to output a pulse skip control signal based on a pulse skip reference voltage; and a second controller configured to control the pulse skip reference voltage based on a threshold current.

[0026] In one embodiment, the second controller includes: a multiplexer configured to output one of set threshold current data and reference threshold current data based on a selection signal; and a reference voltage generator configured to generate a pulse skip reference voltage based on the output of the multiplexer.

[0027] In an embodiment, the second controller may further include a logic gate that outputs a selection signal based on reference power voltage data and the power voltage data.

[0028] In one embodiment, when the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, the power voltage data has a logic high level, and the selection signal has a logic high level, causing the multiplexer to output the reference threshold current data as a pulse to skip the reference voltage. When the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, the power voltage data has a logic low level, and the selection signal has a logic low level, causing the multiplexer to output the set threshold current data as a pulse to skip the reference voltage.

[0029] A method for operating a display device includes: supplying a panel power voltage to a display panel of the display device via a voltage generator; controlling the level of the panel power voltage by switching the operating mode of the voltage generator between a low-power mode and a normal mode based on the magnitude of the load current relative to a threshold current, wherein the voltage generator operates in a low-power mode when the load current is less than the threshold current and in a normal mode when the load current is greater than the threshold current; and reducing the threshold current when the absolute value of the panel power voltage becomes lower than the absolute value of a reference power voltage by selecting a pulse skip reference voltage for the reference threshold current data.

[0030] In this method, a voltage generator is controlled to reduce the switching frequency of the switching element included in the voltage generator in low-power mode to a level lower than the switching frequency of the switching element in normal mode.

[0031] As described above, the voltage generator of the display device can operate in either a low-power mode or a normal mode based on the magnitude of the load current relative to the threshold current. In low-power mode, the voltage generator can control the output pulses of a second power voltage. Accordingly, the power consumption of the display device can be reduced.

[0032] Furthermore, the threshold current can be altered when the absolute value of the second power voltage is lower than the absolute value of the reference power voltage. For example, the threshold current can be reduced when the absolute value of the second power voltage is lower than the absolute value of the reference power voltage. This reduction in the threshold current allows the voltage generator to operate in normal mode when the load current is low. Correspondingly, when the absolute value of the second power voltage decreases in low-power mode, the voltage generator can operate in normal mode, and the ripple of the second power voltage can be reduced. Consequently, flickering on the display panel can be reduced. Consequently, the display quality of the display panel can be improved. Attached Figure Description

[0033] The illustrative, non-limiting embodiments will be more clearly understood through the following detailed description in conjunction with the accompanying drawings.

[0034] Figure 1 This is a block diagram illustrating a display device according to an embodiment of the present invention.

[0035] Figure 2 It is shown in the figure. Figure 1 A circuit diagram of an example pixel circuit.

[0036] Figure 3 It is shown in the diagram Figure 1 A conceptual diagram of the load current flowing in the display panel.

[0037] Figure 4 This is a conceptual diagram illustrating the operation in low-power mode.

[0038] Figure 5 It is shown in the figure. Figure 1 The voltage generator depends on Figure 3 A conceptual diagram showing the magnitude of the load current and the operation in low-power mode or normal mode.

[0039] Figure 6 It is shown in the figure. Figure 5 Conceptual diagrams of pulse skipping mode in low-power mode and discontinuous conduction mode and continuous conduction mode in normal mode.

[0040] Figure 7 It is shown in the figure. Figure 1 A block diagram of the voltage generator converter included in the display device.

[0041] Figure 8 It is shown in the figure. Figure 7 A block diagram of the second controller included in the converter.

[0042] Figure 9 The diagram shows the application to Figure 8 The second controller's set threshold current data and set threshold current table.

[0043] Figure 10 The diagram shows the... Figure 1 A graph showing the relationship between the second electrical voltage output by the voltage generator included in the display device and the threshold current.

[0044] Figure 11 The diagram shows the... Figure 1 A table showing an example of the relationship between the second electrical voltage output by the voltage generator and the threshold current.

[0045] Figure 12 The diagram shows the... Figure 1 A table showing an example of the relationship between the second electrical voltage output by the voltage generator and the threshold current.

[0046] Figure 13 The diagram shows the... Figure 1 A table showing an example of the relationship between the second electrical voltage output by the voltage generator and the threshold current.

[0047] Figure 14 The diagram shows the... Figure 1 A table showing an example of the relationship between the second electrical voltage output by the voltage generator and the threshold current.

[0048] Figure 15 The diagram shows the... Figure 1 A table showing an example of the relationship between the second power voltage output by the voltage generator, the set threshold current, and the threshold current.

[0049] Figure 16 This is a graph showing the second electrical voltage in the comparative example.

[0050] Figure 17 This is a graph illustrating the second power voltage in this embodiment.

[0051] Figure 18 It is shown in the figure. Figure 1 A circuit diagram of an example of pixel circuitry included in a display device.

[0052] Figure 19 It is shown in the figure. Figure 1 A circuit diagram of an example of pixel circuitry included in a display device.

[0053] Figure 20 This is a block diagram illustrating an electronic device according to an embodiment of the present invention.

[0054] Figure 21 , Figure 22 as well as Figure 23 This is a schematic diagram illustrating an electronic device according to an embodiment. Detailed Implementation

[0055] The inventive concept will be explained in detail below with reference to the accompanying drawings.

[0056] It should be understood that although the terms "first," "second," "third," etc., may be used herein to describe various elements or voltage or current levels, these elements or voltage or current levels should not be limited by these terms. Unless the context otherwise indicates, these terms are used only to distinguish one element or voltage or current level from another element or voltage or current level. Therefore, a first element or first level discussed in one part of this specification may be referred to as a second element or second level in another part of this specification or in the claims without departing from the teachings of the invention. Furthermore, in some cases, even if a term such as "first," "second," etc., is not used to describe a term in this specification, it may still be referred to as "first" or "second" in the claims in order to distinguish the different elements or different levels claimed from each other.

[0057] The display device may include a display panel and a voltage generator that supplies panel power voltage to the display panel based on an input voltage. The voltage generator can control the output level of the panel power voltage by switching its operating mode between a low-power mode and a normal mode based on the magnitude of the load current relative to a threshold current. In an embodiment, when the absolute value of the panel power voltage is greater than the absolute value of a reference power voltage, the threshold current increases accordingly from the first threshold current to the second threshold current as the absolute value of the panel power voltage decreases from a first absolute value to a second absolute value. When the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, the threshold current increases from the third threshold current to the fourth threshold current as the absolute value of the panel power voltage decreases from a third absolute value to a fourth absolute value. The voltage generator is configured to control the third threshold current at the third absolute value of the panel power voltage to be less than the second threshold current at the second absolute value of the panel power voltage. In an embodiment, the threshold current increases as the absolute value of the panel power voltage decreases. When the absolute value of the panel power voltage becomes lower than the absolute value of the reference power voltage, the threshold current decreases instantaneously to reduce the threshold current difference between the low-power mode and the normal mode, thereby suppressing flickering on the display panel. Accordingly, the display quality of the display panel can be improved. In an embodiment, the method for operating the display device includes: supplying a panel power voltage to the display panel of the display device via a voltage generator; controlling the level of the panel power voltage by switching the operating mode of the voltage generator between a low-power mode and a normal mode based on the magnitude of the load current relative to a threshold current, wherein the voltage generator operates in a low-power mode when the load current is less than the threshold current and in a normal mode when the load current is greater than the threshold current; and reducing the threshold current by selecting a pulse skipping reference voltage data in response to the absolute value of the panel power voltage becoming lower than a reference power voltage. Accordingly, the ripple of the panel power voltage can be reduced, and the occurrence of flicker on the display panel can be reduced. As a result, the display quality of the display panel can be improved.

[0058] Figure 1 This is a block diagram illustrating a display device 1 according to an embodiment of the present invention.

[0059] refer to Figure 1 An embodiment of the display device 1 may include a display panel 100 and a display panel driver. The display panel driver may include a drive controller 200, a gate driver 300, a gamma reference voltage generator 400, a data driver 500, a transmit driver 600, and a voltage generator 700.

[0060] The display panel 100 may include a display area on which an image is displayed and a peripheral area adjacent to the display area.

[0061] The display panel 100 may include multiple gate lines GL, multiple emission lines EL, multiple data lines DL, and multiple pixels or pixel circuits PX electrically connected to the gate lines GL, emission lines EL, and data lines DL. The gate lines GL may extend in a first direction D1, the emission lines EL may extend in the first direction D1, and the data lines DL may extend in a second direction D2 that intersects the first direction D1.

[0062] The drive controller 200 can receive input image data IMG and input control signal CONT from an external device. In an embodiment, for example, the input image data IMG may include red image data, green image data, and blue image data. The input image data IMG may include white image data. The input image data IMG may include magenta image data, cyan image data, and yellow image data. The input control signal CONT may include a master clock signal and a data enable signal. The input control signal CONT may further include a vertical synchronization signal and a horizontal synchronization signal.

[0063] The drive controller 200 can generate a first control signal CONT1, a second control signal CONT2, a third control signal CONT3, a fourth control signal CONT4, a fifth control signal CONT5, and a data signal DATA based on the input image data IMG and the input control signal CONT.

[0064] The drive controller 200 can generate a first control signal CONT1 for controlling the operation of the gate driver 300 based on the input control signal CONT, and output the first control signal CONT1 to the gate driver 300. The first control signal CONT1 may include a vertical start signal and a gate clock signal.

[0065] The drive controller 200 can generate a second control signal CONT2 for controlling the operation of the data driver 500 based on the input control signal CONT, and output the second control signal CONT2 to the data driver 500. The second control signal CONT2 may include a horizontal start signal and a load signal.

[0066] The drive controller 200 can generate a data signal DATA based on the input image data IMG. The drive controller 200 can output the data signal DATA to the data driver 500.

[0067] The drive controller 200 can generate a third control signal CONT3 for controlling the operation of the gamma reference voltage generator 400 based on the input control signal CONT, and output the third control signal CONT3 to the gamma reference voltage generator 400.

[0068] The drive controller 200 can generate a fourth control signal CONT4 for controlling the operation of the transmitter driver 600 based on the input control signal CONT, and output the fourth control signal CONT4 to the transmitter driver 600.

[0069] The drive controller 200 can generate a fifth control signal CONT5 for controlling the operation of the voltage generator 700 based on the input control signal CONT, and output the fifth control signal CONT5 to the voltage generator 700.

[0070] The gate driver 300 can generate a gate signal for driving the gate line GL in response to a first control signal CONT1 received from the drive controller 200. The gate driver 300 can output the gate signal to the pixels of the display panel 100 through the gate line GL.

[0071] In one embodiment, the gate driver 300 may be implemented separately and disposed in the peripheral region. Alternatively, the gate driver 300 may be integrated into a component disposed in the peripheral region.

[0072] The gamma reference voltage generator 400 can generate a gamma reference voltage VGREF in response to a third control signal CONT3 received from the drive controller 200. The gamma reference voltage generator 400 can provide the gamma reference voltage VGREF to the data driver 500. The gamma reference voltage VGREF can have a value corresponding to the level of the data signal DATA.

[0073] In an embodiment, the gamma reference voltage generator 400 may be integrated into the drive controller 200 or the data driver 500.

[0074] The data driver 500 can receive a second control signal CONT2 and a data signal DATA from the drive controller 200, and a gamma reference voltage VGREF from the gamma reference voltage generator 400. The data driver 500 can use the gamma reference voltage VGREF to convert the data signal DATA into an analog data voltage VDATA. The data driver 500 can output the data voltage VDATA to the pixels of the display panel 100 via the data line DL.

[0075] In one embodiment, the data driver 500 may be implemented separately and located in the peripheral area. Alternatively, the data driver 500 may be integrated into a component located in the peripheral area.

[0076] The transmitter driver 600 can generate a transmission signal in response to a fourth control signal CONT4 received from the drive controller 200. The transmitter driver 600 can output the transmission signal to the pixels of the display panel 100 via the transmission line EL.

[0077] In one embodiment, the transmit driver 600 may be implemented separately and disposed in the peripheral area. Alternatively, the transmit driver 600 may be integrated into a component disposed in the peripheral area.

[0078] Although for the sake of ease of description, Figure 1 The figure illustrates an embodiment in which a gate driver 300 is disposed on a first side of a peripheral region of the display panel 100 adjacent to the display area, and a transmitter driver 600 is disposed on a second side of a peripheral region of the display panel 100 adjacent to the display area; however, the invention is not limited thereto. In another embodiment, the gate driver 300 and the transmitter driver 600 may be disposed on the same side of the peripheral region of the display panel 100. Specifically, the gate driver 300 and the transmitter driver 600 may be disposed on opposite sides of the peripheral region of the display panel 100, or they may be disposed on the same side of the peripheral region of the display panel 100. In embodiments, for example, the gate driver 300 and the transmitter driver 600 may be integrally formed as a single chip.

[0079] Voltage generator 700 can receive a fifth control signal CONT5 from drive controller 200. Voltage generator 700 can receive an input voltage from an external device in response to the fifth control signal CONT5. Voltage generator 700 can generate panel power voltages ELVDD and ELVSS based on this input voltage. Voltage generator 700 can apply the panel power voltages ELVDD and ELVSS to display panel 100. The input voltage can be in the range of 2.9V to 5V. For example, the input voltage can be approximately 5V. For example, the input voltage can be approximately 4.0V. For example, the input voltage can be approximately 2.9V.

[0080] Voltage generator 700 can switch the switching elements included in voltage generator 700 to generate inductor current, and can generate panel power voltages ELVDD and ELVSS based on the inductor current. Panel power voltages ELVDD and ELVSS can include a high power voltage or a first power voltage ELVDD and a low power voltage or a second power voltage ELVSS. The first power voltage ELVDD can be higher than the second power voltage ELVSS. The first power voltage ELVDD can have a positive voltage value (e.g., 5V), and the second power voltage ELVSS can have a negative voltage value (e.g., -5V). Voltage generator 700 can adjust the voltage level of the second power voltage ELVSS to maintain a stable brightness of display panel 100. For example, when the brightness of display panel 100 decreases, voltage generator 700 can increase the absolute value of the second power voltage ELVSS to increase the luminous density of the pixels of display panel 100. Conversely, when the brightness of the display panel 100 becomes high, the voltage generator 700 can reduce the absolute value of the second power voltage ELVSS to reduce the luminous density of the pixels of the display panel 100.

[0081] In one embodiment, the voltage generator 700 may include a first converter and a second converter. The first converter may generate a first electrical voltage ELVDD based on the input voltage. The second converter may generate a second electrical voltage ELVSS based on the input voltage.

[0082] In this embodiment, the first converter may be a boost converter. When the first converter is a boost converter, it can boost the input voltage to generate a first power voltage ELVDD.

[0083] In an embodiment, the second converter can be an inverting buck-boost converter. The inverting buck-boost converter, as the second converter, can generate a second power voltage ELVSS based on the input voltage by switching the switching elements included in the inverting buck-boost converter. When the switching elements are turned on, energy can be accumulated in the inductor; subsequently, when the switching elements are turned off, the stored energy is transferred to the output node (e.g., the second power voltage ELVSS), thereby generating a regulated negative output voltage.

[0084] Figure 2 It is shown in the figure. Figure 1 A circuit diagram of an example pixel circuit PX. Figure 3 It is shown in the diagram Figure 1 A conceptual diagram of the load current IPL flowing in the display panel 100.

[0085] refer to Figures 1 to 3The pixel circuit PX may include a first transistor T1, a second transistor T2, a storage capacitor CST, and a light-emitting element EE.

[0086] The first transistor T1 may include a control electrode connected to a first node N1, a first electrode connected to a second node N2 to receive a first power voltage ELVDD, and a second electrode connected to the first electrode of the light-emitting element EE. The first transistor T1 may generate a drive current IEE based on the difference between the voltage of the control electrode and the voltage of the first electrode.

[0087] The second transistor T2 may include a control electrode connected to the gate line GL to receive the gate signal GS, a first electrode connected to the data line DL to receive the data voltage VDATA, and a second electrode connected to the first node N1. The second transistor T2 can transmit the data voltage VDATA to the first node N1 in response to the gate signal GS.

[0088] The storage capacitor CST may include a first electrode that receives a first electrical voltage ELVDD and a second electrode connected to a first node N1. The storage capacitor CST may store a data voltage VDATA.

[0089] The light-emitting element EE may include a first electrode connected to the second electrode of the first transistor T1 and a second electrode receiving a second electrical voltage ELVSS. The light-emitting element EE may emit light based on a drive current IEE. The brightness of the image may be determined based on the magnitude of the drive current IEE.

[0090] like Figure 2 As shown, the first transistor T1 and the second transistor T2 can be implemented as positive (P-type) transistors, but the inventive concept is not limited thereto. The first transistor T1 and the second transistor T2 can alternatively be implemented as negative (N-type) transistors. Although Figure 2 The figure shows a pixel circuit PX comprising two transistors T1 and T2 and a capacitor CST, but the invention is not limited thereto. The pixel circuit PX may include three or more transistors and / or two or more capacitors.

[0091] like Figure 2 As shown, the pixel circuit PX can generate a drive current IEE flowing between the first power voltage ELVDD and the second power voltage ELVSS. Figure 3 As shown, the display panel 100 may include pixel circuitry PX and can generate a panel current flowing between a first power voltage ELVDD and a second power voltage ELVSS. This panel current may be referred to as the load current. In this respect, the drive current IEE may correspond to a per-pixel value, while the load current IPL may correspond to a per-panel value.

[0092] The load current IPL corresponding to the same gray level can vary depending on the size of the display panel 100. For example, at gray level 10, the drive current IEE can be uniform across the pixel circuits PX. However, since the number of pixel circuits PX varies with the size of the display panel 100, the overall load current IPL can also vary accordingly.

[0093] Figure 4 This is a conceptual diagram illustrating the operation in low-power mode.

[0094] refer to Figures 1 to 4 The display device 1 can operate in an always-on display (AOD) mode, in which the display panel 100 displays a time image or date image even during standby or sleep mode.

[0095] Since the display device 1 operates with low grayscale and / or low brightness in the Always-On Display (AOD) mode, the display device 1 may require low power in the Always-On Display (AOD) mode. Therefore, the voltage generator 700 can operate in either a normal mode or a low-power mode. The voltage generator 700 can reduce power consumption by operating in a low-power mode. In the following text, the normal mode may be designated as the first mode, and the low-power mode may be designated as the second mode.

[0096] although Figure 4 The illustration only shows an example of an always-on display AOD mode in which the voltage generator 700 operates in low-power mode, but the inventive concept is not limited thereto. The low-power mode of the voltage generator 700 can be applied to various embodiments where the display device 1 needs to reduce power consumption. However, for ease of explanation, the always-on display AOD mode is described as an example of the need to reduce power consumption of the display device 1. Furthermore, the voltage generator 700 according to embodiments of the inventive concept can be applied to both the first converter and the second converter, but for ease of explanation, the second converter with the voltage generator 700 operating in low-power mode will be described.

[0097] Figure 5 It is shown in the figure. Figure 1 The voltage generator 700 depends on Figure 3 The concept diagram shows the magnitude of the load current IPL and the operation in low power mode LP_MODE or normal mode N_MODE. Low power mode LP_MODE can include pulse skip mode PSM, and normal mode N_MODE can include discontinuous conduction mode DCM and continuous conduction mode CCM. Figure 6 It is shown in the diagram Figure 5Conceptual diagrams of the inductor current IL waveform in the Pulse Skip Mode (PSM) of the low power mode (LP_MODE) and the inductor current IL waveforms in the discontinuous conduction mode (DCM) and continuous conduction mode (CCM) of the normal mode (N_MODE).

[0098] refer to Figures 1 to 6 The voltage generator 700 can use the input voltage to generate a second power voltage ELVSS, and the display panel 100 can use the second power voltage ELVSS to generate a load current IPL.

[0099] When the display device 1 operates in Always On Display (AOD) mode, it can operate with low grayscale and / or low brightness, resulting in a decrease in the load current IPL. In this case, the operating mode of the voltage generator 700 can be determined based on the magnitude of the load current IPL relative to the threshold current ITH, where the threshold current ITH can serve as a reference for this determination.

[0100] For example, the operating mode of voltage generator 700 can be switched between normal mode N_MODE and low-power mode LP_MODE based on the magnitude of the load current IPL relative to the threshold current ITH. When the load current IPL is less than the threshold current ITH, voltage generator 700 can operate in low-power mode LP_MODE. When the load current IPL is greater than or equal to the threshold current ITH, voltage generator 700 can operate in normal mode N_MODE.

[0101] In an embodiment, the low-power mode may be a pulse skip mode (PSM), and the normal mode may be a discontinuous conduction mode (DCM) or a continuous conduction mode (CCM).

[0102] While operating in Pulse Skip Mode (PSM), the voltage generator 700 can intermittently skip the switching of the switching elements included in the voltage generator 700. Accordingly, during certain periods of PSM, the inductor current IL may not be generated, and therefore, during these periods, a pulsed waveform may not be included. As a result, in PSM, the waveform of the inductor current IL can intermittently omit the pulsed waveform, thereby reducing the number of pulses in the pulsed waveform. Conversely, in Discontinuous Conductive Mode (DCM) or Continuous Conductive Mode (CCM), the waveform of the inductor current IL can continuously include a pulsed waveform.

[0103] In discontinuous conduction mode (DCM), although the switching of the switching elements included in the voltage generator 700 is not skipped, the inductor current IL may increase and decrease discontinuously.

[0104] In continuous conduction mode (CCM), the switching of the switching elements included in the voltage generator 700 is not skipped, and therefore the inductor current IL can be continuously increased and decreased.

[0105] The power consumption of voltage generator 700 in pulse skip mode (PSM) is less than that in discontinuous conduction mode (DCM). The power consumption of voltage generator 700 in discontinuous conduction mode (DCM) is also less than that in continuous conduction mode (CCM).

[0106] Figure 7 It is shown in the figure. Figure 1 A block diagram of an example of a voltage generator 700 converter 710 included in the display device 1. Figure 8 It is shown in the figure. Figure 7 A block diagram of an example of the second controller 712 included in the converter 710. Figure 9 The diagram shows the application to Figure 8 The second controller 712 has a table of set threshold current data ID and set threshold current SITH. Figure 10 The diagram shows the... Figure 1 A graph showing the relationship between the second power voltage ELVSS generated by the voltage generator 700 of the display device 1 and the threshold current ITH.

[0107] refer to Figures 1 to 10 The converter 710 can receive an input voltage VIN. The converter 710 can use the input voltage VIN to generate a second power voltage ELVSS. The converter 710 can selectively operate in either a low-power mode LP_MODE or a normal mode N_MODE, depending on the magnitude of the load current IPL relative to the threshold current ITH, where the threshold current ITH can serve as a reference for that selection.

[0108] The converter 710 may include a first controller 711, a second controller 712, a first amplifier A1, a second amplifier A2, a third amplifier A3, a first switching element VT1, a second switching element VT2, an inductor L, a capacitor C, a first resistor R1, and a second resistor R2.

[0109] The first controller 711 can switch the first switching element VT1 and the second switching element VT2 in response to the pulse skip control signal PSM_EN and the skip signal PSK, thereby controlling the output level of the second power voltage ELVSS. The voltage generator 700 can operate in a low-power mode in response to the activation level of the pulse skip control signal PSM_EN, and can operate in a normal mode in response to the deactivation level of the pulse skip control signal PSM_EN. The first controller 711 can turn the first switching element VT1 on or off, thereby controlling the on-time of the first switching element VT1. The first controller 711 can turn the second switching element VT2 on or off, thereby controlling the on-time of the second switching element VT2. The first controller 711 can alternately turn the first switching element VT1 and the second switching element VT2 on.

[0110] The first switching element VT1 may include a control electrode connected to the first controller 711, a first electrode receiving the input voltage VIN, and a second electrode connected to the first node VN1. The second switching element VT2 may include a control electrode connected to the first controller 711, a first electrode connected to the first node VN1, and a second electrode connected to the second node VN2, which is the output node for the second power voltage ELVSS. The inductor L may include a first terminal connected to the first node VN1 and a second terminal connected to ground. The capacitor C may include a first terminal connected to the second node VN2 and a second terminal connected to ground.

[0111] like Figure 7 As illustrated, the first switching element VT1 and the second switching element VT2 can be implemented as N-type transistors, but the invention is not limited thereto. The first switching element VT1 and the second switching element VT2 can also be implemented as P-type transistors.

[0112] When the first switching element VT1 is turned on and the second switching element VT2 is turned off, an inductor current IL can flow through the inductor L. As a result, an electromotive force (EMF) may be induced around the inductor L due to the inductor current IL. Subsequently, when the first switching element VT1 is turned off and the second switching element VT2 is turned on, the EMF energy stored in the inductor L is transferred to the second node VN2 (i.e., the output node of the second power voltage ELVSS) with opposite voltage polarity, thereby converting the input voltage VIN into the second power voltage ELVSS.

[0113] The first resistor R1 may include a first terminal connected to the second node VN2 and a second terminal connected to the third node VN3. The second resistor R2 may include a first terminal connected to the third node VN3 and a second terminal connected to ground voltage. In an embodiment, a feedback voltage VFB may be output from the second terminal of the first resistor R1. The feedback voltage VFB may have a value between the ground voltage and the second power voltage ELVSS.

[0114] The first amplifier A1 may include a first input terminal for receiving a feedback voltage VFB, a second input terminal for receiving a reference voltage VREF, and an output terminal for outputting a control voltage VCTRL. The first amplifier A1 generates the control voltage VCTRL by amplifying the voltage difference between the feedback voltage VFB and the reference voltage VREF. Since the control voltage VCTRL is generated based on a second power voltage ELVSS, it can reflect changes in the second power voltage ELVSS.

[0115] The second amplifier A2 may include a first input terminal for receiving a pulse skip reference voltage PSM_REF, a second input terminal for receiving a control voltage VCTRL, and an output terminal for outputting a pulse skip control signal PSM_EN. The second amplifier A2 can compare the pulse skip reference voltage PSM_REF with the control voltage VCTRL and amplify the difference between them, thereby outputting the pulse skip control signal PSM_EN. In this respect, the second amplifier A2 can be considered a comparator.

[0116] The third amplifier A3 may include a first input terminal for receiving a summed voltage VSLP, a second input terminal for receiving a control voltage VCTRL, and an output terminal for outputting a skip signal PSK. The third amplifier A3 can compare the summed voltage VSLP with the control voltage VCTRL to generate the skip signal PSK. The summed voltage VSLP can be generated based on the inductor current IL and therefore reflects changes in the inductor current IL.

[0117] The second controller 712 can output a pulse to skip the reference voltage PSM_REF.

[0118] refer to Figure 8 The second controller 712 may include a multiplexer MUX, a logic gate AND1, and a reference voltage generator 712-1.

[0119] A multiplexer MUX may include a first input terminal INL for receiving set threshold current data ID, a second input terminal INH for receiving reference threshold current data RD, a third input terminal for receiving a selection signal SEL, and an output terminal OUT for outputting one of the set threshold current data ID and the reference threshold current data RD. The multiplexer MUX can output one of the set threshold current data ID and the reference threshold current data RD based on the selection signal SEL. For example, when the selection signal SEL is logic high, the multiplexer MUX can output the reference threshold current data RD, and when the selection signal SEL is logic low, the multiplexer MUX can output the set threshold current data ID.

[0120] refer to Figure 9The threshold current data ID can be data representing the set threshold current SITH. The set threshold current SITH can be used as a reference value for the threshold current ITH at various levels of the second power voltage ELVSS. For example, the set threshold current SITH can be set to 5mA. When the second power voltage ELVSS is approximately -4V, the set threshold current SITH can be used as a reference to determine the threshold current ITH. When the threshold current ITH is below 5mA, the voltage generator can operate in low-power mode. Subsequently, when the second power voltage ELVSS becomes approximately -3V, the threshold current ITH increases and becomes greater than 5mA. Accordingly, the operating mode of the voltage generator can be changed to normal mode. In another case, the set threshold current SITH can be set to 20mA. When the threshold current ITH is below 20mA at a second power voltage ELVSS of -3V, the voltage generator can operate in low-power mode at a second power voltage ELVSS of -3V. Subsequently, when the second power voltage ELVSS becomes approximately -1V, the threshold current ITH can increase to approximately 100mA (which is greater than the set threshold current SITH of 20mA), and the voltage generator can change its operating mode to normal mode. Therefore, the threshold current ITH can decrease to below 20mA at a second power voltage ELVSS of -1V. Due to the large difference between the threshold current ITH in low-power mode and the threshold current ITH in normal mode at a second power voltage ELVSS of -1V, flickering may occur in the displayed image on the display panel 100. In another case, the set threshold current SITH is approximately 5mA. When the second power voltage ELVSS is approximately -4V, the set threshold current SITH can be used as a reference to determine the threshold current ITH. When the threshold current ITH is greater than 5mA, the voltage generator can operate in normal mode. Subsequently, when the second power voltage ELVSS becomes approximately -5V, the threshold current ITH can decrease and become less than approximately 5mA (which is less than the set threshold current SITH), and the voltage generator can change its operating mode to low-power mode at the second power voltage ELVSS of -5V. Since the threshold current ITH can vary based on the absolute value of the second power voltage ELVSS, the set threshold current SITH can be set differently based on the set threshold current data ID. For example, when the set threshold current data ID is 00, the set threshold current SITH can be set to approximately 5mA. When the set threshold current data ID is 01, the set threshold current SITH can be set to approximately 10mA. When the set threshold current data ID is 10, the set threshold current SITH can be set to approximately 15mA. When the set threshold current data ID is 11, the set threshold current SITH can be set to approximately 20mA.Considering that the threshold current ITH decreases when the absolute value of the second power voltage ELVSS increases, and the threshold current ITH increases when the absolute value of the second power voltage ELVSS decreases, the threshold current SITH can be set as a balance between reducing power consumption and minimizing flickering.

[0121] The reference threshold current data RD can be user-defined data. The reference threshold current data RD can be one of the set threshold current data IDs. For example, a user can set the reference threshold current data RD to 5mA by selecting one of the set threshold current data IDs corresponding to 5mA from different values ​​of the set threshold current SITH.

[0122] refer to Figure 8 The logic gate AND1 may include a first input terminal for receiving reference voltage data RC, a second input terminal for receiving voltage data SC, and an output terminal for outputting a selection signal SEL. The logic gate AND1 can output the selection signal SEL based on the reference voltage data RC and the voltage data SC. In an embodiment, the logic gate AND1 can be an AND gate. When the logic gate AND1 is an AND gate, it can perform a logical AND operation on the reference voltage data RC and the voltage data SC.

[0123] The reference power voltage data RC may include information related to the reference power voltage RVSS. In an embodiment, the reference power voltage data RC may be set to a logic high level to enable the second controller 712 to generate a pulse to skip the reference voltage PSM_REF.

[0124] The power voltage data SC can include information related to the second power voltage ELVSS. For example, when the absolute value of the second power voltage ELVSS is lower than the absolute value of the reference power voltage RVSS, the power voltage data SC can have a logic high level. Accordingly, when the absolute value of the second power voltage ELVSS is lower than the absolute value of the reference power voltage RVSS, the logic gate AND1 can output a selection signal SEL with a logic high level. For example, when the absolute value of the second power voltage ELVSS is equal to or higher than the absolute value of the reference power voltage RVSS, the power voltage data SC can have a logic low level. Accordingly, when the absolute value of the second power voltage ELVSS is equal to or higher than the absolute value of the reference power voltage RVSS, the logic gate AND1 can output a selection signal SEL with a logic low level.

[0125] The reference voltage generator 712-1 can output a pulse-skip reference voltage PSM_REF corresponding to one of the set threshold current data ID and reference threshold current data RD selected by the multiplexer MUX. For example, the pulse-skip reference voltage PSM_REF may include a data code corresponding to the voltage level used to determine the threshold current ITH.

[0126] refer to Figure 10 According to the comparative example, the threshold current ITH can increase as the absolute value of the second power voltage ELVSS decreases. Conversely, according to this embodiment, when the absolute value of the second power voltage ELVSS is greater than the absolute value of the reference power voltage RVSS, the threshold current ITH can increase as the absolute value of the second power voltage ELVSS decreases. However, when the absolute value of the second power voltage ELVSS drops to the absolute value of the reference power voltage RVSS, the threshold current ITH can decrease instantaneously at the reference power voltage RVSS, and then increase again as the absolute value of the second power voltage ELVSS further decreases.

[0127] In this embodiment, the voltage generator 700 can operate in a low-power mode or a normal mode based on the magnitude of the load current IPL relative to the threshold current ITH. In low-power mode, the voltage generator 700 can extend the pulse skipping period while generating the second power voltage ELVSS by setting the threshold current SITH to a relatively high value (e.g., 20mV), thereby reducing the overall switching frequency of the switching elements. Accordingly, the power consumption of the display device 1 can be reduced.

[0128] When the absolute value of the second power voltage ELVSS drops to the absolute value of the reference power voltage RVSS, the threshold current ITH can change in the opposite direction. For example, when the absolute value of the second power voltage ELVSS becomes lower than the absolute value of the reference power voltage RVSS, the threshold current ITH can decrease instantaneously. Since the threshold current ITH can decrease instantaneously when the absolute value of the second power voltage ELVSS drops to the absolute value of the reference power voltage RVSS, the voltage generator 700 can change its operating mode from low-power mode to normal mode. When the absolute value of the second power voltage ELVSS is lower than the absolute value of the reference power voltage RVSS, since the voltage generator 700 can change its operating mode from low-power mode to normal mode at a lower threshold current ITH in a certain region, the ripple of the second power voltage ELVSS can be reduced. Accordingly, the occurrence of flicker on the display panel 100 can be reduced, thereby improving the display quality of the display panel 100.

[0129] Figure 11 The diagram shows the... Figure 1A table showing an example of the relationship between the second power voltage ELVSS output by the voltage generator 700 and the threshold current ITH.

[0130] refer to Figures 1 to 11 Each value of the threshold current ITH can represent the load current when the operating mode of the voltage generator 700 changes between a low-power mode and a normal mode under the corresponding second power voltage ELVSS. For example, when the set threshold current SITH is set to a first set threshold current (e.g., 5mA), the threshold current ITH can have a first threshold current I1A at a first voltage level VSS1. The first voltage level VSS1 can be approximately -7V. The threshold current ITH can have a second threshold current I2A at a second voltage level VSS2 of the second power voltage ELVSS. The second voltage level VSS2 can be approximately -6V. The second threshold current I2A can be greater than the first threshold current I1A. The threshold current ITH can have a third threshold current I3A at a third voltage level VSS3 of the second power voltage ELVSS. The third voltage level VSS3 can be approximately -5V. The third threshold current I3A can be greater than the second threshold current I2A. The threshold current ITH can have a fourth threshold current I4A at a fourth voltage level VSS4 of the second power voltage ELVSS. The fourth voltage level VSS4 can be approximately -4V. The fourth threshold current I4A can be greater than the third threshold current I3A. The threshold current ITH can have a fifth threshold current I5A at the fifth voltage level VSS5 of the second power voltage ELVSS. The fifth voltage level VSS5 can be approximately -3V. The fifth threshold current I5A can be greater than the fourth threshold current I4A. The threshold current ITH can have a sixth threshold current I6A at the sixth voltage level VSS6 of the second power voltage ELVSS. The sixth voltage level VSS6 can be approximately -2V. The sixth threshold current I6A can be greater than the fifth threshold current I5A. The threshold current ITH can have a seventh threshold current I7A at the seventh voltage level VSS7 of the second power voltage ELVSS. The seventh voltage level VSS7 can be approximately -1V. The seventh threshold current I7A can be greater than the sixth threshold current I6A.

[0131] Figure 12 The diagram shows the... Figure 1 A table showing an example of the relationship between the second power voltage ELVSS output by the voltage generator 700 and the threshold current ITH.

[0132] refer to Figures 1 to 12When the set threshold current SITH is set to a second set threshold current (e.g., 10mA), the threshold current ITH can have a first threshold current I1B at a first voltage level VSS1 of the second power voltage ELVSS. The threshold current ITH can have a second threshold current I2B at a second voltage level VSS2 of the second power voltage ELVSS. The second threshold current I2B can be greater than the first threshold current I1B. The threshold current ITH can have a third threshold current I3B at a third voltage level VSS3 of the second power voltage ELVSS. The third threshold current I3B can be greater than the second threshold current I2B. The threshold current ITH can have a fourth threshold current I4B at a fourth voltage level VSS4 of the second power voltage ELVSS. The fourth threshold current I4B can be greater than the third threshold current I3B. The threshold current ITH can have a fifth threshold current I5B at a fifth voltage level VSS5 of the second power voltage ELVSS. The fifth threshold current I5B can be greater than the fourth threshold current I4B. The threshold current ITH can have a sixth threshold current I6A corresponding to the first set threshold current at the sixth voltage level VSS6 of the second power voltage ELVSS. The sixth voltage level VSS6 of the second power voltage ELVSS can be the reference power voltage RVSS. Therefore, the sixth threshold current I6A can be obtained from the reference threshold current data RD (instead of from...). Figure 8 The threshold current SITH is selected from one of the set threshold current data IDs. When the reference threshold current data RD is set to 5mA corresponding to the first set threshold current, the threshold current ITH can have a sixth threshold current I6A corresponding to the first set threshold current. The sixth threshold current I6A can be less than the fifth threshold current I5B. The threshold current ITH can have a seventh threshold current I7A corresponding to the first set threshold current at the seventh voltage level VSS7 of the second power voltage ELVSS. The seventh threshold current I7A can be greater than the sixth threshold current I6A.

[0133] In this embodiment, when the absolute value of the second power voltage ELVSS is lower than the absolute value of the reference power voltage RVSS, the threshold current ITH can be changed accordingly. For example, when the absolute value of the second power voltage ELVSS becomes lower than the absolute value of the reference power voltage RVSS, the threshold current ITH can decrease instantaneously. This instantaneous decrease in the threshold current ITH allows the voltage generator 700 to operate in normal mode even when the load current IPL is low. Correspondingly, when the absolute value of the second power voltage ELVSS decreases in low-power mode, the voltage generator 700 can operate in normal mode, and the ripple of the second power voltage ELVSS can be reduced. Consequently, the occurrence of flicker on the display panel 100 can be reduced, thereby improving the display quality of the display panel 100.

[0134] Figure 13 The diagram shows the... Figure 1 A table showing an example of the relationship between the second power voltage ELVSS output by the voltage generator 700 and the threshold current ITH.

[0135] refer to Figures 1 to 11 as well as Figure 13 When the set threshold current SITH is set to a third set threshold current (e.g., 15mA), the threshold current ITH can have a first threshold current I1C at the first voltage level VSS1 of the second power voltage ELVSS. The threshold current ITH can have a second threshold current I2C at the second voltage level VSS2 of the second power voltage ELVSS. The second threshold current I2C can be greater than the first threshold current I1C. The threshold current ITH can have a third threshold current I3C at the third voltage level VSS3 of the second power voltage ELVSS. The third threshold current I3C can be greater than the second threshold current I2C. The threshold current ITH can have a fourth threshold current I4C at the fourth voltage level VSS4 of the second power voltage ELVSS. The fourth threshold current I4C can be greater than the third threshold current I3C. The threshold current ITH can have a fifth threshold current I5C at the fifth voltage level VSS5 of the second power voltage ELVSS. The fifth threshold current I5C can be greater than the fourth threshold current I4C. The sixth voltage level VSS6 can be the reference power voltage RVSS. The threshold current ITH can have a sixth threshold current I6A corresponding to the first set threshold current at the sixth voltage level VSS6 of the second power voltage ELVSS. The sixth voltage level VSS6 of the second power voltage ELVSS can be the reference power voltage RVSS. Therefore, the sixth threshold current I6A can be obtained from the reference threshold current data RD (instead of from...). Figure 8The threshold current SITH is selected from one of the set threshold current data IDs. When the reference threshold current data RD is set to 5mA corresponding to the first set threshold current, the threshold current ITH can have a sixth threshold current I6A corresponding to the first set threshold current. The sixth threshold current I6A can be less than the fifth threshold current I5C. The threshold current ITH can have a seventh threshold current I7A corresponding to the first set threshold current at the seventh voltage level VSS7 of the second power voltage ELVSS. The seventh threshold current I7A can be greater than the sixth threshold current I6A.

[0136] In this embodiment, when the absolute value of the second power voltage ELVSS is lower than the absolute value of the reference power voltage RVSS, the threshold current ITH can be changed accordingly. For example, when the absolute value of the second power voltage ELVSS becomes lower than the absolute value of the reference power voltage RVSS, the threshold current ITH can decrease instantaneously. This instantaneous decrease in the threshold current ITH allows the voltage generator 700 to operate in normal mode even when the load current IPL is low. Correspondingly, when the absolute value of the second power voltage ELVSS decreases in low-power mode, the voltage generator 700 can operate in normal mode, and the ripple of the second power voltage ELVSS can be reduced. Consequently, the occurrence of flicker on the display panel 100 can be reduced, thereby improving the display quality of the display panel 100.

[0137] Figure 14 The diagram shows the... Figure 1 A table showing an example of the relationship between the second power voltage ELVSS output by the voltage generator 700 and the threshold current ITH.

[0138] refer to Figures 1 to 11 as well as Figure 14When the set threshold current SITH is set to the fourth set threshold current (e.g., 20mA), the threshold current ITH can have a first threshold current I1D at the first voltage level VSS1 of the second power voltage ELVSS. The threshold current ITH can have a second threshold current I2D at the second voltage level VSS2 of the second power voltage ELVSS. The second threshold current I2D can be greater than the first threshold current I1D. The threshold current ITH can have a third threshold current I3D at the third voltage level VSS3 of the second power voltage ELVSS. The third threshold current I3D can be greater than the second threshold current I2D. The threshold current ITH can have a fourth threshold current I4D at the fourth voltage level VSS4 of the second power voltage ELVSS. The fourth threshold current I4D can be greater than the third threshold current I3D. The threshold current ITH can have a fifth threshold current I5D at the fifth voltage level VSS5 of the second power voltage ELVSS. The fifth threshold current I5D can be greater than the fourth threshold current I4D. The sixth voltage level VSS6 can be the reference power voltage RVSS. The threshold current ITH can have a sixth threshold current I6A corresponding to the first set threshold current at the sixth voltage level VSS6 of the second power voltage ELVSS. The sixth voltage level VSS6 of the second power voltage ELVSS can be the reference power voltage RVSS. Therefore, the sixth threshold current I6A can be obtained from the reference threshold current data RD (instead of from...). Figure 8 The threshold current SITH is selected from one of the set threshold current data IDs. When the reference threshold current data RD is set to 5mA corresponding to the first set threshold current, the threshold current ITH can have a sixth threshold current I6A corresponding to the first set threshold current. The sixth threshold current I6A can be less than the fifth threshold current I5D. The threshold current ITH can have a seventh threshold current I7A corresponding to the first set threshold current at the seventh voltage level VSS7 of the second power voltage ELVSS. The seventh threshold current I7A can be greater than the sixth threshold current I6A.

[0139] In this embodiment, the threshold current ITH can be changed accordingly when the absolute value of the second power voltage ELVSS is lower than the absolute value of the reference power voltage RVSS. For example, when the absolute value of the second power voltage ELVSS becomes lower than the absolute value of the reference power voltage RVSS, the threshold current ITH can decrease instantaneously. This instantaneous decrease in the threshold current ITH allows the voltage generator 700 to operate in normal mode even when the load current IPL is low. For example, when the threshold current SITH is set to 20mA, the threshold current ITH can reach as high as 100mA while operating in low-power mode at the reference power voltage RVSS (e.g., -2V). As the operating mode is changed to normal mode, the threshold current ITH can be changed to below 20mA. Due to the sudden change in the threshold current ITH at or below the reference power voltage RVSS, the brightness of the display panel may change abruptly, resulting in a perceived flicker while an image is displayed on the display panel. By selecting the reference threshold current data RD instead of setting one of the threshold current data IDs when the reference power voltage RVSS is at or below it, the threshold current difference between the low-power mode and the normal mode can be reduced. Accordingly, when the absolute value of the second power voltage ELVSS decreases in the low-power mode, the voltage generator 700 can change its operating mode to the normal mode at a lower level of the threshold current ITH, and the ripple of the second power voltage ELVSS can be reduced. Consequently, the occurrence of flicker on the display panel 100 can be reduced, thereby improving the display quality of the display panel 100.

[0140] Figure 15 The diagram shows the... Figure 1 A table showing an example of the relationship between the second power voltage ELVSS output by the voltage generator 700 and the set threshold current SITH and ITH.

[0141] refer to Figures 1 to 15 When the set threshold current SITH is set to a first set threshold current (e.g., 5mA) and the reference power voltage RVSS is set to -2V, the threshold current ITH can be approximately 6mA at a second power voltage ELVSS of -4V. At a second power voltage ELVSS of -2V, the threshold current ITH can be approximately 15mA. At a second power voltage ELVSS of -1.95V, the threshold current ITH can be approximately 16mA. At a second power voltage ELVSS of -1V, the threshold current ITH can be approximately 39mA.

[0142] When the set threshold current SITH is set to a second set threshold current (e.g., 10mA) and the reference power voltage RVSS is set to -2V, the threshold current ITH can be approximately 10mA at a second power voltage ELVSS of -4V. At a second power voltage ELVSS of -2V, the threshold current ITH can be approximately 27mA. At a second power voltage ELVSS of -1.95V, the threshold current ITH can be approximately 16mA. At a second power voltage ELVSS of -1V, the threshold current ITH can be approximately 38mA. By selecting the reference threshold current data RD instead of the set threshold current data ID at or below the reference power voltage RVSS, the threshold current ITH at a second power voltage ELVSS at or below the reference power voltage RVSS (e.g., -1.95V and -1V) can correspond to the threshold current ITH at a set threshold current of the first set threshold current (e.g., 5mA).

[0143] When the set threshold current SITH is set to a third set threshold current (e.g., 15mA) and the reference power voltage RVSS is set to -2V, the threshold current ITH can be approximately 16mA at a second power voltage ELVSS of -4V. At a second power voltage ELVSS of -2V, the threshold current ITH can be approximately 40mA. At a second power voltage ELVSS of -1.95V, the threshold current ITH can be approximately 16mA. At a second power voltage ELVSS of -1V, the threshold current ITH can be approximately 39mA. By selecting the reference threshold current data RD instead of one of the set threshold current data IDs at or below the reference power voltage RVSS, the threshold current ITH at a second power voltage ELVSS at or below the reference power voltage RVSS (e.g., -1.95V and -1V) can correspond to the threshold current ITH at a set threshold current of the first set threshold current (e.g., 5mA).

[0144] When the set threshold current SITH is set to the fourth set threshold current (e.g., 20mA) and the reference power voltage RVSS is set to -2V, the threshold current ITH can be approximately 21mA at a second power voltage ELVSS of -4V. At a second power voltage ELVSS of -2V, the threshold current ITH can be approximately 49mA. At a second power voltage ELVSS of -1.95V, the threshold current ITH can be approximately 16mA. At a second power voltage ELVSS of -1V, the threshold current ITH can be approximately 38mA. By selecting the reference threshold current data RD instead of one of the set threshold current data IDs at or below the reference power voltage RVSS, the threshold current ITH at a second power voltage ELVSS at or below the reference power voltage RVSS (e.g., -1.95V and -1V) can correspond to the threshold current ITH at the first set threshold current (e.g., 5mA).

[0145] In this embodiment, when the absolute value of the second power voltage ELVSS becomes lower than the absolute value of the reference power voltage RVSS, the threshold current ITH can be changed by selecting one of the reference threshold current data RD instead of the set threshold current data ID. For example, when the absolute value of the second power voltage ELVSS becomes lower than the absolute value of the reference power voltage RVSS, the threshold current ITH can decrease because the reference threshold current data RD can be less than the set threshold current data ID. Since the threshold current ITH can decrease when the absolute value of the second power voltage ELVSS is lower than the absolute value of the reference power voltage RVSS, the voltage generator 700 can change its operating mode from low-power mode to normal mode even when the load current IPL is low. Accordingly, when the absolute value of the second power voltage ELVSS decreases in low-power mode, the voltage generator 700 can operate in normal mode, and the ripple of the second power voltage ELVSS can be reduced. Consequently, the occurrence of flicker on the display panel 100 can be reduced, thereby improving the display quality of the display panel 100.

[0146] Figure 16 The figure shows the waveform of the fluctuation of the second power voltage ELVSS in the comparative example. Figure 17 The figure shows the waveform of the fluctuation of the second power voltage ELVSS in this embodiment.

[0147] refer to Figures 1 to 17 In the comparative example, the threshold current SITH can be set to 20mA. When the second power voltage ELVSS is approximately -1V, the ripple of the second power voltage ELVSS can correspond to the first voltage variation range V1.

[0148] Conversely, in this embodiment, the set threshold current SITH can be set to 5mA by selecting a reference threshold current data RD (e.g., 5mA) instead of selecting one of the set threshold current data IDs (e.g., 20mA) at or below the reference power voltage RVSS (e.g., -2V). When the second power voltage ELVSS is approximately -1V and the set threshold current SITH is approximately 5mA, the ripple of the second power voltage ELVSS can correspond to a second voltage variation range V2, which is smaller than the first voltage variation range V1.

[0149] Accordingly, in this embodiment, the ripple of the second power voltage ELVSS can be reduced, and the occurrence of flicker on the display panel 100 can be reduced. As a result, the display quality of the display panel 100 can be improved.

[0150] Figure 18 It is shown in the figure. Figure 1 A circuit diagram of an example of the pixel circuit PX included in the display device 1.

[0151] refer to Figure 1 and Figure 18 The pixel circuit PXA may include a first transistor T1A, a second transistor T2A, a third transistor T3A, a fourth transistor T4A, a fifth transistor T5A, a sixth transistor T6A, a seventh transistor T7A, a first capacitor or storage capacitor C1A, and a light-emitting element EE.

[0152] The first transistor T1A may include a control electrode connected to a first node N1A, a first electrode connected to a second node N2A, and a second electrode connected to a third node N3A. The first transistor T1A can generate a drive current based on the voltage of the first node N1A. The first transistor T1A may be referred to as a drive transistor. In this embodiment, the first transistor T1A may be a P-type transistor.

[0153] The second transistor T2A may include a control electrode for receiving the write gate signal GW, a first electrode for receiving the data voltage VDATA, and a second electrode connected to the second node N2A. The second transistor T2A can transmit the data voltage VDATA to the second node N2A in response to the write gate signal GW. The second transistor T2A may be referred to as a write transistor.

[0154] The third transistor T3A may include a control electrode that receives the compensation gate signal GC, a first electrode connected to the third node N3A, and a second electrode connected to the first node N1A. The third transistor T3A can connect the first node N1A and the third node N3A in response to the compensation gate signal GC. When the third transistor T3A is turned on in response to the compensation gate signal GC, the first transistor T1A is connected in diode form. The third transistor T3A may be referred to as the compensation transistor.

[0155] The fourth transistor T4A may include a control electrode that receives the initialization gate signal GI, a first electrode that receives the initialization voltage VINT, and a second electrode connected to the first node N1A. The fourth transistor T4A can transmit the initialization voltage VINT to the first node N1A in response to the initialization gate signal GI. The fourth transistor T4A may be referred to as the initialization transistor.

[0156] The fifth transistor T5A may include a control electrode for receiving the transmit signal EM, a first electrode for receiving the high power voltage ELVDD, and a second electrode connected to the second node N2A. The fifth transistor T5A may supply the high power voltage ELVDD to the second node N2A in response to the transmit signal EM. The fifth transistor T5A may be referred to as the first emitter transistor.

[0157] The sixth transistor T6A may include a control electrode for receiving the transmit signal EM, a first electrode connected to the third node N3A, and a second electrode connected to the fourth node N4A. The sixth transistor T6A may connect the third node N3A and the fourth node N4A in response to the transmit signal EM. The sixth transistor T6A may be referred to as the second emitter transistor.

[0158] The seventh transistor T7A may include a control electrode that receives the initialization gate signal GB, a first electrode that receives the initialization voltage VAINT of the light-emitting element, and a second electrode connected to the fourth node N4A. The seventh transistor T7A may transmit the initialization voltage VAINT of the light-emitting element to the fourth node N4A in response to the initialization gate signal GB.

[0159] The storage capacitor C1A may include a first electrode that receives a high power voltage ELVDD and a second electrode connected to a first node N1A. The storage capacitor C1A can store the voltage of the first node N1A. The first capacitor C1A may be referred to as a storage capacitor.

[0160] The light-emitting element EE may include a first electrode connected to the fourth node N4A and a second electrode receiving a low power voltage ELVSS. The light-emitting element EE can emit light based on a drive current.

[0161] Figure 19It is shown in the figure. Figure 1 A circuit diagram of an example of the pixel circuit PX included in the display device 1.

[0162] refer to Figure 1 and Figure 19 The pixel circuit PXB may include a first transistor T1B, a second transistor T2B, a third transistor T3B, a fourth transistor T4B, a fifth transistor T5B, a sixth transistor T6B, a first capacitor C1B, and a light-emitting element EE. In an embodiment, the pixel circuit PXB may further include a second capacitor C2B.

[0163] The first transistor T1B may include a control electrode connected to a first node N1B, a first electrode connected to a second node N2B, and a second electrode connected to a third node N3B. The first transistor T1B can generate a drive current based on the voltage of the first node N1B. In an embodiment, the first transistor T1B may further include a back gate control electrode connected to the third node N3B. The first transistor T1B may be referred to as a drive transistor. In this embodiment, the first transistor T1B may be an N-type transistor.

[0164] The second transistor T2B may include a control electrode for receiving a write gate signal GW, a first electrode for receiving a data voltage VDATA, and a second electrode connected to the first node N1B. The second transistor T2B can transmit the data voltage VDATA to the first node N1B in response to the write gate signal GW. The second transistor T2B may be referred to as a write transistor.

[0165] The third transistor T3B may include a control electrode that receives a reset gate signal GR, a first electrode that receives a pixel reference voltage VREF, and a second electrode connected to the first node N1B. The third transistor T3B can transmit the pixel reference voltage VREF to the first node N1B in response to the reset gate signal GR. The third transistor T3B may be referred to as an initialization transistor.

[0166] The fourth transistor T4B may include a control electrode for receiving the transmit signal EM, a first electrode for receiving the first power voltage ELVDD, and a second electrode connected to the second node N2B. The fourth transistor T4B may supply the first power voltage ELVDD to the second node N2B in response to the transmit signal EM. The fourth transistor T4B may be referred to as the first emitter transistor.

[0167] The fifth transistor T5B may include a control electrode for receiving the second transmit signal EMB, a first electrode connected to the third node N3B, and a second electrode connected to the fourth node N4B. The fifth transistor T5B may connect the third node N3B and the fourth node N4B in response to the second transmit signal EMB. The fifth transistor T5B may be referred to as the second emitter transistor.

[0168] The sixth transistor T6B may include a control electrode that receives the initialization gate signal GI, a first electrode that receives the light-emitting element initialization voltage VAINT, and a second electrode connected to the fourth node N4B. The sixth transistor T6B can transmit the light-emitting element initialization voltage VAINT to the fourth node N4B in response to the initialization gate signal GI. The sixth transistor T6C may be referred to as the light-emitting element initialization transistor.

[0169] The first capacitor C1B may include a first electrode connected to a first node N1B and a second electrode connected to a third node N3B. The second capacitor C2B may include a first electrode receiving a first electrical voltage ELVDD and a second electrode connected to a third node N3B.

[0170] The light-emitting element EE may include a first electrode connected to the fourth node N4B and a second electrode receiving a second power voltage ELVSS. The light-emitting element EE may emit light based on a drive current.

[0171] Figure 20 This is a block diagram illustrating an electronic device 10 according to an embodiment of the present invention.

[0172] refer to Figure 20 The electronic device 10 according to the embodiment may include a display module 11, a processor 12, a memory 13, and a power module 14.

[0173] Processor 12 may include at least one of a central processing unit (CPU), an application processor (AP), a graphics processing unit (GPU), a communication processor (CP), an image signal processor (ISP), and a controller. Processor 12 may output... Figure 1 The input control signal CONT.

[0174] The memory 13 can store the data information required for the operation of the processor 12 or the display module 11. When the processor 12 executes the application program stored in the memory 13, image data signals and / or input control signals are transmitted to the display module 11, and the display module 11 can process the received signals and output image information through the display screen.

[0175] The power module 14 may include a power supply module such as a power adapter or battery device, and a power conversion module that converts the power supplied by the power supply module to generate the power required for the operation of the electronic device 10. In an embodiment, the power module 14 may be... Figure 1 The voltage generator 700.

[0176] The electronic device 10 may further include an input module 15, an output module or non-image output module 16 and / or a communication module 17.

[0177] Input module 15 can provide input information to processor 12 and / or display module 11. Input module 15 may include various sensor modules as well as physical buttons, keyboard, and microphone. Examples of sensor modules may include touch sensors, pressure sensors, proximity sensors, position sensors, digitizers, motion recognition sensors, camera sensors, light receiving sensors, photoelectric conversion sensors, temperature sensors, and biosensors such as blood pressure sensors, blood glucose sensors, electrocardiogram sensors, and heart rate sensors.

[0178] The non-image output module 16 can receive information other than images from the processor 12 and provide that information to the user. Examples of the non-image output module 16 may include an audio module, a haptic module, a light-emitting module, etc., and may include other functional modules unique to the electronic device (e.g., a refrigeration module of a refrigerator).

[0179] The communication module 17 may be a module responsible for transmitting and receiving information between the electronic device 10 and an external device, and may include a receiving unit and a transmitting unit. The communication module 17 may include various wireless communication modules such as mobile communication modules, Wi-Fi modules, Bluetooth modules, or various wired communication modules.

[0180] At least one of the components of the electronic device 10 described above may be included in the display device according to the embodiments described above. Furthermore, some functional sub-modules of the module may be included in the display device, and other functional sub-modules may be provided as independent components outside the display device. For example, the display device may include a display module 11, and the processor 12, memory 13, and power module 14 may be provided within the electronic device 10 as other devices besides the display device.

[0181] Figures 21 to 23 This is a schematic diagram illustrating an electronic device according to an embodiment.

[0182] refer to Figure 21Smartphone 10_1a, tablet PC 10_1b, laptop computer 10_1c, television 10_1d, and desktop monitor 10_1e are examples of electronic devices.

[0183] In addition to the display module 11, the smartphone 10_1a may also include an input module (such as a touch sensor) and a communication module. The smartphone 10_1a can process information received through the communication module or other input modules and display that information through the display module of the display device.

[0184] In the case of tablet PC 10_1b, laptop computer 10_1c, television 10_1d, and desktop monitor 10_1e, a display module similar to that of smartphone 10_1a and an input module may be included, and in some cases, a communication module may be further included.

[0185] refer to Figure 22 Electronic devices, including display modules, can be used in wearable electronic devices. Wearable electronic devices can include smart glasses 10_2a, head-mounted displays 10_2b, smartwatches 10_2c, etc.

[0186] The smart glasses 10_2a and the head-mounted display 10_2b may include a display module that emits a display image and a reflector that reflects the emitted display image and provides it to the user's eyes, thereby providing the user with virtual reality or augmented reality images.

[0187] The smartwatch 10_2c may include a biosensor as an input device, and the biometric information identified by the biosensor can be provided to the user through a display module.

[0188] refer to Figure 23 Electronic devices, including display modules, can be applied to vehicles. For example, electronic device 10_3 can be applied to the vehicle's dashboard, center console, etc., or can be applied to a central information display (CID) placed on the vehicle's dashboard or an interior rearview mirror display that replaces the side rearview mirrors.

[0189] Although not illustrated, electronic devices to which the display device according to the embodiments is applied can include not only devices that primarily display images (such as billboards, electronic boards, and game consoles), but also various household appliances (such as refrigerators, washing machines, dryers, air conditioners, and robot vacuum cleaners) that display information via the display module. Furthermore, when the display module has the function of transmitting light, it can be applied to electronic devices such as smart windows or transparent display devices that display a background along with the displayed image. The types of electronic devices according to the embodiments are not limited to the examples described herein, and can also be applied to various other electronic devices not specifically illustrated.

[0190] The display device according to the embodiments can be applied to display devices included in computers, laptops, mobile phones, smartphones, smart tablets, PMPs, PDAs, or MP3 players.

[0191] The foregoing examples are for illustrative purposes only and should not be construed as limiting the inventive concept. Although several embodiments of the inventive concept have been described, those skilled in the art will readily appreciate that many modifications can be made to the embodiments without substantially departing from the novel teachings and advantages of the inventive concept. Accordingly, all such modifications are intended to be included within the scope of the inventive concept as defined in the claims. In the claims, the device plus function clause is intended to cover structures described herein as performing the illustrated functions, and not only structural equivalents but also equivalent structures. Therefore, it should be understood that the foregoing is illustrative of the inventive concept and should not be construed as limiting to the specific embodiments disclosed, and modifications to the disclosed embodiments and other embodiments are intended to be included within the scope of the appended claims. The inventive concept is defined by the claims, wherein equivalents of the claims should be included.

Claims

1. A display device, comprising: Display panel, including pixel circuitry; as well as A voltage generator is configured to generate a panel power voltage based on an input voltage and supply the panel power voltage to the display panel. The voltage generator is configured to control the output level of the panel power voltage by switching the operating mode of the voltage generator based on the magnitude of the load current relative to a threshold current. When the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, as the absolute value of the panel power voltage decreases from a first absolute value to a second absolute value, the threshold current correspondingly increases from the first threshold current to the second threshold current. Wherein, when the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, as the absolute value of the panel power voltage decreases from a third absolute value to a fourth absolute value, the threshold current increases from a third threshold current to a fourth threshold current, and The voltage generator is configured to control the third threshold current at the third absolute value of the panel power voltage to be less than the second threshold current at the second absolute value of the panel power voltage.

2. The display device according to claim 1, wherein, The voltage generator is configured to operate in a low-power mode when the load current is less than the threshold current, and in a normal mode when the load current is greater than the threshold current.

3. The display device according to claim 2, wherein, The switching frequency of the switching elements included in the voltage generator in the low-power mode is lower than the switching frequency of the switching elements in the normal mode.

4. The display device according to claim 1, wherein, When the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, the threshold current increases as the absolute value of the panel power voltage decreases; and when the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, the threshold current increases as the absolute value of the panel power voltage decreases.

5. The display device according to any one of claims 1 to 4, wherein, The voltage generator includes: The first controller is configured to control the output of the panel power voltage based on a pulse skip control signal; An amplifier is configured to output the pulse skip control signal based on a pulse skip reference voltage; and The second controller is configured to control the pulse skip reference voltage based on the threshold current.

6. The display device according to claim 5, wherein, The second controller includes: The multiplexer is configured to output one of a set threshold current data and a reference threshold current data based on a selection signal; and A reference voltage generator is configured to generate the pulse skip reference voltage based on the output of the multiplexer.

7. The display device according to claim 6, wherein, The second controller further includes logic gates that output the selection signal based on reference power voltage data and the power voltage data.

8. The display device according to claim 7, wherein, When the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, the power voltage data has a logic high level, and the selection signal has a logic high level, causing the multiplexer to output the reference threshold current data as the pulse skip reference voltage.

9. The display device according to claim 7, wherein, When the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, the power voltage data has a logic low level, and the selection signal has a logic low level, causing the multiplexer to output the set threshold current data as the pulse skip reference voltage.

10. The display device according to claim 7, wherein, The multiplexer includes a first terminal for receiving the set threshold current data, a second terminal for receiving the reference threshold current data, a third terminal for receiving the selection signal, and an output terminal for outputting one of the set threshold current data and the reference threshold current data. The logic gate includes a first terminal for receiving the reference power voltage data, a second terminal for receiving the power voltage data, and an output terminal for outputting the selection signal.

11. The display device according to claim 7, wherein, The logic gate is an AND gate configured to perform a logical AND operation between the reference power voltage data and the power voltage data.

12. An electronic device comprising: Display panel, including pixel circuitry; The display panel driver is configured to control the display panel based on input control signals; as well as The processor is configured to output the input control signal. The display panel driver includes a voltage generator configured to apply a panel power voltage to the display panel based on an input voltage. The voltage generator is configured to control the output level of the panel power voltage by switching the operating mode of the voltage generator based on the magnitude of the load current relative to a threshold current. When the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, as the absolute value of the panel power voltage decreases from a first absolute value to a second absolute value, the threshold current correspondingly increases from the first threshold current to the second threshold current. Wherein, when the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, as the absolute value of the panel power voltage decreases from a third absolute value to a fourth absolute value, the threshold current increases from a third threshold current to a fourth threshold current, and The voltage generator is configured to control the third threshold current at the third absolute value of the panel power voltage to be less than the second threshold current at the second absolute value of the panel power voltage.

13. The electronic device according to claim 12, wherein, The voltage generator is configured to operate in a low-power mode when the load current is less than the threshold current and in a normal mode when the load current is greater than the threshold current, and the switching frequency of the switching elements included in the voltage generator in the low-power mode is less than the switching frequency of the switching elements in the normal mode.

14. The electronic device according to claim 12, wherein, When the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, the threshold current increases as the absolute value of the panel power voltage decreases; when the absolute value of the panel power voltage becomes lower than the absolute value of the reference power voltage, the threshold current decreases; and when the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, the threshold current increases as the absolute value of the panel power voltage decreases.

15. The electronic device according to any one of claims 12 to 14, wherein, The voltage generator includes: The first controller is configured to control the output of the panel power voltage based on a pulse skip control signal; An amplifier is configured to output the pulse skip control signal based on a pulse skip reference voltage; and The second controller is configured to control the pulse skip reference voltage based on the threshold current.

16. The electronic device according to claim 15, wherein, The second controller includes: The multiplexer is configured to output one of a set threshold current data and a reference threshold current data based on a selection signal; and A reference voltage generator is configured to generate the pulse skip reference voltage based on the output of the multiplexer.

17. The electronic device according to claim 16, wherein, The second controller further includes logic gates that output the selection signal based on reference power voltage data and the power voltage data.

18. The electronic device according to claim 17, wherein, When the absolute value of the panel power voltage is lower than the absolute value of the reference power voltage, the power voltage data has a logic high level, and the selection signal has a logic high level, causing the multiplexer to output the reference threshold current data as the pulse skip reference voltage. Conversely, when the absolute value of the panel power voltage is greater than the absolute value of the reference power voltage, the power voltage data has a logic low level, and the selection signal has a logic low level, causing the multiplexer to output the set threshold current data as the pulse skip reference voltage.

19. A method for operating a display device, comprising: A voltage generator supplies panel power voltage to the display panel of the display device. The level of the panel power voltage is controlled by switching the operating mode of the voltage generator between a low-power mode and a normal mode based on the magnitude of the load current relative to the threshold current, wherein the voltage generator operates in the low-power mode when the load current is less than the threshold current and in the normal mode when the load current is greater than the threshold current. as well as In response to the absolute value of the panel power voltage becoming lower than the absolute value of the reference power voltage, the threshold current is reduced by selecting the reference threshold current data as a pulse skip reference voltage.

20. The method of claim 19, further comprising: The voltage generator is controlled to reduce the switching frequency of the switching elements included in the voltage generator in the low-power mode to a level lower than the switching frequency of the switching elements in the normal mode.

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