KR20190030286A - power management integrated circuit, OLED display device using the PMIC and operation method thereof - Google Patents

Abstract

The present invention relates to a power control integrated circuit, an organic light emitting display using the same, and a driving method thereof in which the power control integrated circuit operates in a FCCM mode only during a period in which current is applied to a display pixel and operates in a DCM (or PSM) mode in a period in which no current is applied to the pixel. The power control integrated circuit includes an integrated circuit driving power input stage for receiving driving power; an operation signal input stage for receiving a drive start enable signal; a driving voltage output stage for outputting a voltage required for operation of an organic light emitting diode provided in the panel of a display panel unit; a control signal input stage for receiving a control signal provided from a timing controller; and a switch circuit which operates in an FCCM mode only during a period in which a pixel of the display panel is should be turned on and operates in a DCM mode during a period in which the pixel is not turned on, depending upon a control signal inputted through the control signal input stage.

Description

TECHNICAL FIELD [0001] The present invention relates to a power control integrated circuit, an OLED display device using the same, and a power management integrated circuit (OLED)

The present invention relates to a power control integrated circuit and an OLED display using the same and a driving method thereof. More particularly, the present invention relates to a power control integrated circuit (Or PSM) method, thereby maintaining image quality and power consumption, and an OLED display using the same and a driving method thereof.

A power management integrated circuit (PMIC) for a general display device operates differently depending on the output current. That is, as shown in Figure 1, the power control integrated circuit threshold (i _th) based on the output current (i) with the threshold (i _th) size is smaller than a discontinuous current mode (Discontinuous Current Mode of: DCM (Pulse-Skipping Mode) or Pulse-Skipping Mode (PSM). When the threshold value _(th i) based on the output current (i) is greater than the size of the threshold value (i _th) PMIC the CCM: operates in (Continuous Current Mode CCM) method.

FIG. 2 is an exemplary diagram showing a ripple state of an output voltage of a PMIC that varies in operation mode according to the magnitude of an output load. 2A shows the ripple state of the output voltage of the PMIC operating in the CCM system when the output load is large. 2B shows the ripple state of the output voltage of the PMIC operating in the DCM system when the output load is small. As the load current demand decreases, the inductor current is controlled to be "0" during a portion of each cycle to prevent the ripple from being large enough to cause an inversion in the inductor current.

On the other hand, the quality of the image quality is sensitively changed according to the magnitude of the output voltage ripple in the PMIC that supplies power to the OLED display. That is, the larger the ripple, the worse the image quality. Particularly, when the display device operates at a low light load, the characteristics of such a picture quality are well recognized. The PMIC operates in the DCM (or PSM) mode when driving low gradations. However, DCM (or PSM) operation increases the ripple of the output voltage. That is, the picture quality of the display device is lowered.

Therefore, a PMIC used in a portable terminal equipped with an organic light emitting display device, which considers quality of image quality, operates as CCM regardless of the gray scale level. As shown in Fig. 3, even when the operating load is small, the PMIC is forced to operate in the CCM scheme. That is, the increase of the ripple of the output voltage is prevented and the quality of the image quality is prevented from being lowered.

The PMIC used at this time is configured as shown in FIG. 4A. A driving power input terminal (VIN) for receiving driving power from the battery of the portable terminal, a driving signal input terminal (EN) for receiving an operation enable signal, and an output voltage output terminal. According to such a configuration, as shown in FIG. 4B, the PMIC according to the related art always operates in the CCM method regardless of the gray scale by the operation enable signal, and exhibits a constant output voltage. That is, the PMIC according to the related art drives the display device of the portable terminal by applying the Forced Continuous Current Mode (FCCM).

Therefore, although the image quality can always be maintained at high quality, the CCM system always operates, and the power consumption consumed by the power source unit is increased.

An object of the present invention is to provide a power control integrated circuit capable of reducing power consumption while maintaining the quality of image quality, and an organic light emitting display using the same and a method of driving the same.

It is another object of the present invention to provide a power control integrated circuit which is driven by the FCCM method only during a period in which a current is supplied to pixels of a display device, an organic light emitting display using the same, and a driving method thereof.

According to an aspect of the present invention, there is provided a power control integrated circuit including an integrated circuit driving power input terminal receiving driving power; An operation signal input terminal for receiving a drive start enable signal; A driving voltage output terminal for outputting a voltage required for operation of the organic light emitting diode provided in the panel of the display panel unit; A control signal input terminal receiving a control signal provided from a timing controller; And a switch circuit operating in an FCCM mode only in a period in which pixels of the display panel are to be turned on in accordance with a control signal inputted through the control signal input terminal and switching operation to operate in a DCM mode in a period in which pixels are not lit And the like.

A power control integrated circuit according to a preferred embodiment of the present invention includes a pair of driving voltage switches (SWD1, SWD2) connected to a VDD voltage input terminal of a display panel; And a pair of discharge voltage switches SWS1 and SWS2 connected to a VSS voltage input terminal of the display panel.

The first drive voltage switch SWD1 and the first discharge voltage switch SWS1 of the switch circuit of the power control integrated circuit according to the preferred embodiment of the present invention are connected to the first switch logic signal provided from the timing controller and the second switch voltage And is turned on by a logic signal to perform a switching operation so that the operating voltage is applied to the pixels of the display.

An OLED display according to an exemplary embodiment of the present invention includes a display panel unit including a display panel, a gate driver, and a data driver; A timing controller for analyzing a video signal input from the set unit to extract a section provided with a current for lighting pixels of the display panel and outputting a power control signal; And a power control integrated circuit that operates in an FCCM mode only in a period in which pixels of the display panel are to be turned on in accordance with a control signal of the timing controller and operates in a DCM mode in a period in which pixels are not lit do.

The timing controller and the power control integrated circuit may be configured in the set portion or in the display module portion.

A method of driving an organic light emitting display according to the present invention includes: receiving a video signal from a set unit; Analyzing the received video signal; Extracting an interval in which a current is supplied to a pixel of the display panel according to the analyzed result; And outputting a control signal for controlling the power control integrated circuit to operate in the FCCM mode only during a period in which the pixels of the display panel are to be turned on and controlling the power control integrated circuit to operate in the DCM mode .

The power control integrated circuit according to the present invention, the organic light emitting display using the same, and the driving method thereof are as follows.

First, it can reduce the power consumption while maintaining the quality of the display image quality.

Second, the output voltage ripple can be prevented from increasing even when the display is driven in a light load state.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing the operation modes of a general power control integrated circuit. FIG.
2 is an exemplary view showing an operation state of the CCM method and the DCM method of the PMIC according to the related art.
3 is an exemplary view showing an operation state of the forced CCM method of the PMIC according to the related art.
4A is an exemplary view schematically showing a configuration of a PMIC according to the related art.
4B is an exemplary view showing an operation state of the PMIC according to the related art.
5 is a diagram schematically showing a configuration of a PMIC according to the present invention.
FIG. 6A is a diagram illustrating an exemplary structure of an OLED display according to an exemplary embodiment of the present invention. Referring to FIG.
FIG. 6B is a view illustrating a schematic configuration of an OLED display according to another embodiment of the present invention. Referring to FIG.
7 is a diagram illustrating a connection state of a switch according to a control signal input to the PMIC in the organic light emitting diode display according to the present invention.
8 is a circuit diagram showing the configuration of a PMIC in the organic light emitting display according to the present invention in detail.
9 is an exemplary view showing a switch state when the GD and GS signals inputted to the PMIC are in a low state.
10 is an exemplary view showing a switch state when the GD signal input to the PMIC is low and the GS signal is high.
11 is an exemplary view showing a switch state when the GD and GS signals input to the PMIC are all in a high state.
12 is an exemplary view showing an operation state of the PMIC according to the present invention.
13 is a flowchart illustrating a method of driving an organic light emitting display according to an exemplary embodiment of the present invention.

For specific embodiments of the invention disclosed herein, specific structural and functional descriptions are set forth for the purpose of describing an embodiment of the invention only, and it is to be understood that the embodiments of the invention may be embodied in various forms, And should not be construed as limited to the embodiments described.

The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms first, second, etc. may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between. Other expressions that describe the relationship between components, such as "between" and "between" or "neighboring to" and "directly adjacent to" should be interpreted as well.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises ", or" having ", and the like, are intended to specify the presence of stated features, integers, But do not preclude the presence or addition of steps, operations, elements, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be construed to indicate meaning consistent with the meaning of the context in the relevant art and are to be construed as either ideal or overly formal in meaning unless expressly defined in the present application Do not.

On the other hand, if an embodiment is otherwise feasible, the functions or operations specified in a particular block may occur differently than the order specified in the flowchart. For example, two consecutive blocks may actually be performed at substantially the same time, and depending on the associated function or operation, the blocks may be performed backwards.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

5 is a diagram schematically showing a configuration of a PMIC according to the present invention. As shown in the figure, the display panel includes an integrated circuit driving power input terminal (VIN) for receiving driving power, an operation signal input terminal (EN) for receiving a driving start enable signal, and an organic light emitting diode A driving voltage output terminal (VDDEL, VSSEL) for outputting a voltage required for operation; And a control signal input terminal FCCMEN for receiving a control signal provided from the timing controller. The structure of the internal circuit and the operation thereof will be described below.

FIG. 6A is a diagram illustrating an exemplary structure of an OLED display according to an exemplary embodiment of the present invention. Referring to FIG. A timing controller 300 for providing an operation decision signal of the PMIC 100 and a display controller 300 for controlling the display panel 200 to display the operation panel of the display module 210, (1).

The display panel unit 200 includes a display panel 210, a gate driver 210, and a data driver 230.

The timing controller 300 analyzes a video signal input from the set unit and extracts a section in which a current for lighting the pixels of the display panel is provided to output a power control signal (topology determination signal).

The PMIC 100 operates in the FCCM mode only in a period in which the pixels of the display panel 210 are to be turned on according to a control signal of the timing controller 300 and operates in the DCM mode in a period in which pixels are not lit.

FIG. 6B is a view illustrating a schematic configuration of an OLED display according to another embodiment of the present invention. Referring to FIG. Unlike in FIG. 6A, the embodiment of FIG. 6B shows an example in which the timing controller 300 and the PMIC 100 are configured in the set section 2. FIG. The configuration is arranged in the set portion 2, but the operation is the same as that in the display module portion 1.

7 is a diagram illustrating a connection state of a switch according to a control signal input to the PMIC in the organic light emitting diode display according to the present invention. As shown in the figure, the logic signals input to the PMIC are represented by GD and GS and appear in the form of a high signal H and a low signal L, respectively. When both the GD and GS signals are low signals (L), SWD2 and SWS2 are turned on and the PMIC operates as FCCM and is not output. When the GD and GS signals are both high (H), SWD1 and SWS1 are turned on and the PMIC operates as FCCM. When the GD signal is a low signal (L) and the GS signal is a high signal (H), SWD2 and SWS1 are turned on and the PMIC operates as an FCCM and is not output.

8 is a circuit diagram showing the configuration of a PMIC in the organic light emitting display according to the present invention in detail. The PMIC 100 includes a power supply input terminal 110 connected to a terminal VDD for delivering an operating voltage and a V-OFF terminal V-OFF and a ground power source GND, and a control signal GD, GS And a voltage output terminal 130 for transmitting an operation voltage to the display panel 210 according to the connection state of the switch circuit 120. [ The operation of the switch circuit 120 according to the control signals GD and GS may be realized by a device such as a MUX.

The switch circuit 120 includes a pair of driving voltage switches SWD1 and SWD2 connected to a VDD voltage input terminal of the display panel 210; And a pair of discharge voltage switches SWS1 and SWS2 connected to a VSS voltage input terminal of the display panel 210. [

9 is an exemplary view showing a switch state when the GD and GS signals inputted to the PMIC are in a low state. As shown in the table of FIG. 7, when the GD signal and the GS signal are both the low signal L, SWD2 and SWS2 are turned on. V-OFF power is transmitted to the VDDEL terminal and the VSSEL terminal of the display panel 210. [ At this time, the V-OFF power source is not a driving voltage for the organic light emitting diode of the display panel 210 to operate. Therefore, the pixels of the display panel 210 are not turned on, and the PMIC does not operate as an FCCM.

10 is an exemplary view showing a switch state when the GD signal input to the PMIC is low and the GS signal is high. As shown in the table of FIG. 7, when the GD signal is the low signal L and the GS signal is the high signal H, SWD2 and SWS1 are turned on. V-OFF power is supplied to the VDDEL terminal of the display panel 210, and ground power is transmitted to the VSSEL terminal. Therefore, the pixels of the display panel 210 are not turned on, and the PMIC does not operate as an FCCM.

11 is an exemplary view showing a switch state when the GD and GS signals input to the PMIC are all in a high state. As shown in the table of FIG. 7, when the GD signal and the GS signal are both the high signal H, SWD1 and SWS1 are turned on. That is, the first drive voltage switch SWD1 and the first discharge voltage switch SWS1 of the switch circuit 120 are connected to the first switch logic signal GD and the second switch logic signal GD2 provided from the timing controller 300, (ON) state by the switching element GS so that the operating voltage is applied to the pixels of the display. Therefore, the VDD power is supplied to the VDDEL terminal of the display panel 210, and the ground power is transmitted to the VSSEL terminal. Accordingly, the operation current I _OLED is transmitted to the organic light emitting diode of the display panel 210 to emit light. At this time, the PMIC operates as an FCCM.

12 is an exemplary view showing an operation state of the PMIC according to the present invention. As shown in the figure, the PMIC according to the present invention operates in the FCCM mode during the time t _ON when the pixels of the display panel are to be turned on and the PSM (or DCM) during the time t _OFF when the pixels of the display panel are not lit. Quot; drive " Therefore, although the output voltage is constantly provided and there is no change in the image quality, the operation of the FCCM method with a relatively high power consumption rate is performed only while the pixels of the display panel are lit, thereby reducing power consumption.

13 is a flowchart illustrating a method of driving an organic light emitting display according to an exemplary embodiment of the present invention. In the method of driving an OLED display according to the present invention, since the PMIC operates as an FCCM or a DCM (or PSM) according to a control signal of a timing controller, the following process will be described with the timing controller as an operation main body. The video signal is received from the set unit (S1301) and the grayscale of the video signal, particularly the video signal, is analyzed (S1302). Subsequently, a section in which a current is supplied to the pixel of the display panel is extracted according to the analyzed result (S1303). According to the extracted information, the power control integrated circuit is controlled to operate in the FCCM mode only in a section in which pixels of the display panel are to be turned on. In a section in which the pixels are not lit, control signals for controlling the power control integrated circuit to operate in the DCM system (S1304).

As described above, in the power control integrated circuit according to the present invention, the period during which the current is applied to the pixels of the display panel operates in the FCCM mode, and the period during which the pixels of the display panel are not lit is performed by the DCM (or PSM) The power consumption by the power supply circuit can be reduced while maintaining the image quality of the portable display device.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims It can be understood that

1: Display module part 2: Set part
100: PMIC 110: Power input terminal
120: Switch circuit 130: Power output stage
200: display panel unit 210: display panel
220: gate driver 230: data driver
300: timing controller

Claims (7)

An integrated circuit driving power input terminal for receiving driving power;
An operation signal input terminal for receiving a drive start enable signal;
A driving voltage output terminal for outputting a voltage required for operation of the organic light emitting diode provided in the panel of the display panel unit;
A control signal input terminal receiving a control signal provided from a timing controller; And
And a switch circuit which operates in accordance with a control signal inputted through the control signal input terminal in an FCCM mode only during a period in which pixels of the display panel are to be turned on and operates in a DCM mode A power management integrated circuit (PMIC). The semiconductor memory device according to claim 1,
A pair of driving voltage switches (SWD1, SWD2) connected to the VDD voltage input terminal of the display panel;
And a pair of discharge voltage switches (SWS1, SWS2) connected to a VSS voltage input terminal of the display panel. The plasma display apparatus according to claim 2, wherein the first drive voltage switch (SWD1) and the first discharge voltage switch (SWS1) of the switch circuit are turned on by a first switch logic signal and a second switch logic signal provided from the timing controller ) State so that the operating voltage is applied to the pixels of the display. A display panel unit including a display panel, a gate driver, and a data driver;
A timing controller for analyzing a video signal input from the set unit to extract a section provided with a current for lighting pixels of the display panel and outputting a power control signal;
And a power control integrated circuit that operates in an FCCM mode only in a period in which pixels of the display panel are to be turned on according to a control signal of the timing controller and operates in a DCM mode in a period in which pixels are not lit. 5. The method of claim 4,
Wherein the timing controller and the power control integrated circuit are formed in the set portion. 5. The method of claim 4,
Wherein the timing controller and the power control integrated circuit are formed in a display module unit. Receiving a video signal from the set unit;
Analyzing the received video signal;
Extracting an interval in which a current is supplied to a pixel of the display panel according to the analyzed result;
A step of outputting a control signal for controlling the power control integrated circuit to operate in the FCCM mode only during a period in which the pixels of the display panel are to be turned on and controlling the power control integrated circuit to operate in the DCM mode And a power control circuit for controlling the power of the organic light emitting display device.

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