TWI508052B - Gamma voltage driving circuit and related display apparatus - Google Patents

Description

Gamma voltage driving circuit and related display device

The present invention relates to a gamma voltage driving circuit and related display device, and more particularly to a gamma voltage driving circuit including a gamma curve correction function and related display devices.

The gray-scale changes in the color of the human eye are not distributed in a linear manner. For example, the human eye is more sensitive to the grayscale change of the low grayscale picture than the grayscale change of the high grayscale picture. Therefore, the display device usually has a gamma curve correction function to cause the human eye to change the color gray scale change into a linear relationship. Generally, the display device performs gamma curve correction on the input picture data by using a gamma voltage and a reference voltage. Due to the relationship between red light gray scale data and brightness (ie red gamma curve), green light gray scale data and brightness (ie green gamma curve) and blue gray scale data and brightness (ie blue) The gamma curve is slightly different. If only a single gamma voltage and a reference voltage are used to correct the image data, there is still a problem that the human eye does not have a linear relationship with the color gray scale change. For better gamma correction, for grayscale data such as red, green, and blue, you need to use different gamma voltages and reference voltages to correct them.

Please refer to FIG. 1 , which is a schematic diagram of a conventional display device 10 . The display device 10 includes a display panel 11, a source driver 12, a gate driver 13, a timing controller 14, and gamma voltage driving circuits 15R, 15G, and 15B. The display panel 11 includes a plurality of pixel units Px, a plurality of data lines DL, and a plurality of gate lines GL. In the display panel 11, all of the pixel units Px form a matrix of a plurality of rows and columns. Each pixel unit Px includes a switching unit TFT which is driven by a data line DL and a gate line GL to be turned on in a specific time interval so that the pixel unit Px can display a corresponding gray scale. The source driver 12 drives the respective data lines DL to transfer the gray scale data to the pixel units Px of each row. The gate driver 13 drives the gate lines GL to control the switching state of the switching unit TFTs in the pixel unit Px of each column. In a certain time interval, the switching state of the switching unit TFT is turned on, so that the pixel unit Px is displayed. Corresponding to gray scale. Using the principle of visual persistence, the human eye can see the complete display. The timing controller 14 is configured to control the gate driver 13 to sequentially drive the gate lines GL of the display panel 11, and control the source driver 12 to sequentially send the corresponding image data when the gate lines GL are sequentially driven. Each data line DL of the display panel 11 is displayed. The gamma voltage driving circuit 15R generates red gamma voltages V _γ1 (1) to V _γ1 (M1) and a red light reference voltage V _R1 for correcting red light gray scale data. The gamma voltage driving circuit 15G generates green gamma voltages V _γ2 (1) to V _γ2 (M2) and a green light reference voltage V _R2 for correcting the green light gray scale data. The gamma voltage driving circuit 15B generates blue gamma voltages V _γ3 (1) to V _γ3 (M3) and a blue reference voltage V _R3 for correcting blue gradation data.

As described above, the display device 10 uses three gamma voltage driving circuits 15R, 15G, 15B to respectively generate red gamma voltages V _γ1 (1) to V _γ1 (M1) and red light reference voltages V _R1 , green The optical gamma voltages V _γ2 (1) to V _γ2 (M2) and the green light reference voltage V _R2 , the blue gamma voltages V _γ3 (1) to V _γ3 (M3), and the blue reference voltage V _R3 . However, since the conventional display device requires the use of three gamma voltage driving circuits, the production cost of the conventional display device is thus increased.

Accordingly, it is an object of the present invention to provide a gamma voltage driving circuit including a gamma curve correction function and an associated display device for generating red light for correcting red, green, and blue gradation data, Green light, blue gamma voltage and red, green, and blue reference voltages, and can reduce the production cost of the display device.

In accordance with the above objects of the present invention, a gamma voltage driving circuit for providing a plurality of gamma voltages and a plurality of reference voltages is proposed. The gamma voltage driving circuit includes a voltage adjusting unit, a control unit, and a gamma voltage output circuit. The voltage regulation unit is used to provide an input voltage. The control unit is used to generate reference signals and adjustment signals. A gamma voltage output circuit is used to output the gamma voltages and the reference voltages. The gamma voltage output circuit includes a first resistor string and a plurality of gamma voltage generating units. The first resistor string is coupled to the voltage regulating unit. The first series of resistors includes a plurality of resistors in series for providing a plurality of first output voltages based on the input voltage. The gamma voltage generating units are coupled to the resistor string and the control unit. The gamma voltage generating units respectively receive the first output voltage and the reference signal to generate a gamma voltage and a reference voltage.

According to an embodiment of the present invention, the gamma voltage generating singles described above Each of the gamma voltage generating units of the element includes a digital-to-analog converting unit, a second resistor string, a gamma voltage selecting unit, and a reference voltage generating unit. The digital analog conversion unit is configured to receive the first output voltages to generate a first adjustment voltage and a second adjustment voltage. The second resistor string includes a plurality of resistors connected in series for providing a plurality of second output voltages according to the first trim voltage and the second trim voltage. The gamma voltage selection unit is configured to receive the second output voltages to generate a plurality of corresponding gamma voltages of the gamma voltages.

According to still another embodiment of the present invention, the digital analog conversion unit includes a first digital analog converter and a second digital analog converter, and the first digital analog converter is configured to receive a portion of the first output voltages to generate a first adjustment. And a second digital analog converter is operative to receive another portion of the first output voltages to produce a second regulated voltage.

According to still another embodiment of the present invention, each of the gamma voltage generating units further includes a first operational amplifier and a second operational amplifier for boosting the first digital analog converter and the second digital analog converter, respectively. Drive capability.

According to still another embodiment of the present invention, the number of the corresponding gamma voltages is less than or equal to the number of the second output voltages.

According to still another embodiment of the present invention, each of the gamma voltage generating units of the gamma voltage generating units further includes a reference voltage generating unit configured to generate a plurality of corresponding reference voltages of the reference voltages according to the reference signals.

According to still another embodiment of the present invention, the gamma voltage is more A red gamma voltage, a plurality of green gamma voltages, and a plurality of blue gamma voltages, and the reference voltages are red reference voltage green reference voltage and blue reference voltage.

According to still another embodiment of the present invention, the gamma voltage driving circuit further includes a storage unit for storing the reference signal and the adjustment signal.

According to the above object of the present invention, a display device includes a display panel, a timing controller, a gate driver, a source driver, and a gamma voltage driving circuit. . The display panel is used to display a picture according to multiple gate driving signals and multiple gray level data signals. The timing controller is used to generate timing control signals and image data signals. The gate driver is configured to receive timing control signals to generate the gate drive signals. The source driver is configured to receive the image data signal, the plurality of gamma voltages, and the plurality of reference voltages, and the image data signals are adjusted by the gamma voltages and the reference voltages to generate the grayscale data signals. The gamma voltage driving circuit is used to provide a plurality of gamma voltages and a plurality of reference voltages. The gamma voltage driving circuit includes a voltage adjusting unit, a control unit, and a gamma voltage output circuit. The voltage regulation unit is used to provide an input voltage. The control unit is used to generate reference signals and adjustment signals. A gamma voltage output circuit is used to output the gamma voltages and the reference voltages. The gamma voltage output circuit includes a first resistor string and a plurality of gamma voltage generating units. The first resistor string is coupled to the voltage regulating unit. The first series of resistors includes a plurality of resistors in series for providing a plurality of first output voltages based on the input voltage. The gamma voltage generating units are coupled to the resistor string and the control unit. The gamma voltage generating units respectively receive the first output powers Voltage and reference signals to generate gamma voltage and reference voltage.

According to an embodiment of the invention, the display panel is an active matrix organic light-emitting diode (AMOLED) panel.

10,200‧‧‧ display device

11, 210‧‧‧ display panel

12, 240‧‧‧ source driver

13, 230‧‧ ‧ gate driver

14, 220‧‧‧ timing controller

15R, 15G, 15B, 250‧‧‧ gamma voltage drive circuit

251‧‧‧Voltage adjustment unit

252‧‧‧Control unit

253‧‧‧Gamma voltage output circuit

254‧‧‧ storage unit

300, 420‧‧‧resistance series

300A, 300B, 420A, 420B‧‧‧ endpoints

310R, 310G, 310B, 400‧‧‧ gamma voltage generating unit

410‧‧‧Digital Analog Conversion Unit

430‧‧‧Gamma Voltage Selection Unit

440‧‧‧reference voltage generating unit

450‧‧‧ storage unit

510A, 510B‧‧‧Digital Analog Converter

CODE‧‧‧ adjustment signal

DL‧‧‧ data line

GL‧‧‧ gate line

NA, NB‧‧‧ nodes

Px‧‧‧ pixel unit

REF‧‧‧ reference signal

V _γ (1)~V _γ (M), V _γ' (1)~V _γ' (L)‧‧‧ gamma voltage

V _γ1 (1)~V _γ1 (M1)‧‧‧Red gamma voltage

V _γ2 (1)~V _γ2 (M2)‧‧‧Green gamma voltage

V _γ3 (1)~V _γ3 (M3)‧‧‧Blue gamma voltage

V _ADJ1, V _ADJ2 ‧‧‧ voltage adjustment

V _DATA ‧‧‧ image data signal

V _G (1)~V _G (Y)‧‧‧ gate drive signal

V _IN ‧‧‧ input voltage

V _OUT1 (1)~V _OUT1 (J), V _OUT2 (1)~V _OUT2 (Z)‧‧‧ Output voltage

V _P (1)~V _P (X)‧‧‧ Grayscale data signal

V _R (1)~V _R (N), V _REF ‧‧‧reference voltage

V _R1 ‧‧‧red light reference voltage

V _R2 ‧‧‧Green light reference voltage

V _R3 ‧‧‧Blue Reference Voltage

T _CON ‧‧‧ Timing Control Signal

TFT‧‧‧Switch unit

The above and other objects, features, advantages and embodiments of the present invention will become more apparent and understood.

2 is a schematic view showing a display device according to an embodiment of the present invention.

Fig. 3 is a schematic view showing the gamma voltage driving circuit in Fig. 2.

Figure 4 is a schematic diagram showing a gamma voltage generating unit in accordance with an embodiment of the present invention.

Figure 5 is a schematic diagram showing the digital analog conversion unit in Figure 4.

Fig. 6A is a schematic diagram showing an embodiment of a gamma voltage selection unit in Fig. 4.

FIG. 6B is a schematic diagram showing still another embodiment of the gamma voltage selection unit in FIG. 4.

Embodiments of the invention are discussed in detail below. However, it will be appreciated that the embodiments provide many applicable inventive concepts that can be implemented in a wide variety of specific content. The specific embodiments discussed are illustrative only and are not intended to limit the scope of the invention.

Please refer to FIG. 2 , which is a schematic diagram of a display device 200 according to an embodiment of the present invention. The display device 200 includes a display panel 210, a timing controller 220, a gate driver 230, a source driver 240, and a gamma voltage driving circuit 250. The display panel 210 can be any type of liquid crystal display panel, such as a twisted nematic (TN) liquid crystal display panel or a vertical alignment (VA) liquid crystal display panel, or an organic light emitting diode (organic light) Array), but is not limited to this. The display panel 210 displays a picture according to the gate drive signals V _G (1) to V _G (Y) and the gray scale data signals V _P (1) to V _P (X). The display panel 210 includes a plurality of pixel units Px, a plurality of data lines DL, and a plurality of gate lines GL. In the display panel 210, all of the pixel units Px form a matrix of a plurality of rows and columns. The display panel 210 of the present embodiment is exemplified by a pixel unit having X rows and Y columns. Each pixel unit Px includes a switching unit TFT driven by a data line DL and a gate line GL to be turned on in a specific time interval, so that the pixel unit Px can display the gray level data signal V _P ( 1) A pixel image of one of the grayscale data signals in ~V _P (X).

The timing controller 220 generates a timing control signal T _CON and an image data signal V _DATA corresponding to the gray scale data signals V _P (1) to V _P (X). The timing controller 220 controls the gate driver 230 to sequentially drive the respective gate lines GL, and controls the source driver 240 to sequentially drive the corresponding gray line data signals V _P (1) when the gate lines GL are sequentially driven. ~V _P (X) to each data line DL of the display panel 210.

The gate driver 230 receives the timing control signal T _CON and generates gate driving signals V _G (1) V V _G (Y) according to the timing control signal T _CON to drive the gate lines GL to control the pixel units of each column. Switching state of the switching unit TFT in Px. The pixel unit Px displays a pixel corresponding to one of the grayscale data signals V _P (1) to V _P (X) in a specific time interval when the switching state of the switching unit TFT is changed to ON. image.

The source driver 240 receives the image data signal V _DATA , the gamma voltage V _γ (1) to V _γ (M), and the reference voltages V _R (1) to V _R (N), and the gamma voltage V _γ (1)~V _γ (M) and the reference voltage V _R (1)~V _R (N) adjust the image data signal V _DATA to generate corresponding gray scale data signals V _P (1)~V _P (X) . The source driver 240 drives the data lines DL to transfer the gray scale data signals V _P (1) V V _P (X) to the pixel units Px of each row. By the operation of each unit described above, the human eye can view the complete display screen on the display panel 210.

The gamma voltage driving circuit 250 generates the gamma voltages V _γ (1) to V _γ (M) and the reference voltages V _R (1) to V _R (N) for the source driver 240 to correct the image data signal V _DATA . The gamma voltage driving circuit 250 includes a voltage adjusting unit 251, a control unit 252, a gamma voltage output circuit 253, and a storage unit 254. The voltage adjustment unit 251 generates an input voltage V _IN and feeds the input voltage V _IN to the gamma voltage output circuit 253. The control unit 252 generates the reference signal REF and provides an adjustment signal CODE for generating the gamma voltages V _γ (1) V V _γ (M) and the reference voltages V _R (1) V V _R (N), respectively. The gamma voltage output circuit 253 receives the input voltage V _IN , the reference signal REF, and the adjustment signal CODE, and generates a gamma voltage V _γ (1)~V _γ (M) according to the input voltage V _IN , the reference signal REF, and the adjustment signal CODE. Reference voltage V _R (1) ~ V _R (N).

The storage unit 254 can store the reference signal REF and the adjustment signal CODE. The storage unit 254 is preferably a non-volatile memory (non-volatile memory) Memory), when the gamma voltage driving circuit 250 stops operating, the stored reference signal REF and the adjustment signal CODE are not lost for the gamma voltage driving circuit 250 to be used in the next operation. On the other hand, the storage unit 254 can store a plurality of candidate reference signals and a plurality of candidate adjustment signals. When the gamma voltage driving circuit 250 is operated, a reference signal and an adjustment signal can be selected from the plurality of candidate reference signals and the plurality of candidate adjustment signals stored in the storage unit 254.

Please refer to FIG. 3, which is a schematic diagram of the gamma voltage driving circuit 250 in FIG. In FIG. 3, the gamma voltage output circuit 250 includes a resistor string 300 and gamma voltage generating units 310R, 310G, 310B. The terminal 300A of the resistor string 300 is coupled to the voltage regulating unit 251, and the other terminal 300B is coupled to the reference voltage terminal REF. The resistor string 300 includes a plurality of resistors R1 connected in series. In the resistor string 300, there is a node NA between every two adjacent resistors R1, and the voltage value is between the input voltage V _IN and the reference voltage V _REF . Therefore, the resistor string 300 can be used to provide multiple partial voltages. The terminals 300A, 300B of the resistor string 300 and all of the nodes NA are used to provide output voltages V _OUT1 (1) ~ V _OUT1 (J), where the number J of output voltages can be represented by 2 ^K and K is a positive integer. According to different needs, the number of resistors R1 of the resistor string 300 can be adjusted accordingly.

The gamma voltage generating units 310R, 310G, 310B are coupled to the terminals 300A, 300B of the resistor string 300 and all of the nodes NA. In this embodiment, three sets of gamma voltage generating units are taken as an example for different ways. In this embodiment, the gamma voltage generating unit 310R is configured to generate a red gamma voltage V _γ1 (1)~V _γ1 (M1) and a red light reference voltage V of the red light gray scale data in the corrected image data signal V _DATA . _R1 , the gamma voltage generating unit 310G is configured to generate a green gamma voltage V _γ2 (1)~V _γ2 (M2) and a green light reference voltage V _R2 of the green gray scale data in the corrected image data signal V _DATA , and the gamma The mA voltage generating unit 310B is configured to generate a blue gamma voltage V _γ3 (1) ～ V _γ3 (M3) and a blue reference voltage V _{R3 for} correcting the blue gradation data in the image data signal V _DATA . It should be noted that the number of the red gamma voltage, the green gamma voltage, and the blue gamma voltage may be different. Similarly, the number of red gamma voltage, green gamma voltage, and blue gamma voltage can be adjusted accordingly according to different requirements.

Please refer to FIG. 4, which is a schematic diagram of a gamma voltage generating unit 400 according to an embodiment of the present invention. The gamma voltage generating unit 400 may be any one of the gamma voltage generating units 310R, 310G, 310B in FIG. The gamma voltage generating unit 400 includes a digital analog converting unit 410, a resistor string 420, a gamma voltage selecting unit 430, and a reference voltage generating unit 440. The digital analog conversion unit 410 receives the plurality of partial voltages outputted by the resistor string 300, and generates the adjustment voltages V _ADJ1 , V _ADJ2 according to the plurality of voltage divisions output from the resistor string 300 and the adjustment signal CODE provided by the control unit.

The digital analog conversion unit 410 may be a 2 ^K -to-2 (converting 2 ^K inputs to 2 outputs) digital analog converters, or a digital analog converter composed of two multiple input and single outputs. Please refer to FIG. 5 , which is a schematic diagram of the digital analog conversion unit 410 in FIG. 4 . As shown in FIG. 5, the digital analog conversion unit 410 includes digital analog converters 510A, 510B. The digital analog converter 510A is coupled to the terminals 300A, 300B of the resistor string 300 and portions of all the nodes NA, and the digital analog converter 510B is coupled to the terminals 300A, 3001B of the resistor string 300 and all nodes NA. A portion that is not coupled to the digital analog converter 510B. In the present embodiment, the output voltages V _OUT1 (1) to V _OUT1 (J/2) supplied from the resistor string 300 are input to the digital analog converter 510A, and the output voltage V _OUT1 [(J/2)+1] ~V _OUT1 (J) is input to the digital analog converter 510B. The digital analog converter 510A selects an output voltage from the output voltages V _OUT1 (1) to V _OUT1 (J/2) as the adjustment voltage V _ADJ1 according to the adjustment signal CODE. The digital analog converter 510B selects an output voltage from the output voltage V _OUT1 [(J/2)+1]~V _OUT1 (J) as the adjustment voltage V _ADJ2 according to the adjustment signal CODE.

Please return to Figure 4. The resistor string 420 includes a plurality of resistors R2 connected in series. The terminals 420A, 420B of the resistor string 420 are respectively coupled to the output terminals of the output adjustment voltages V _ADJ1 , V _ADJ2 in the digital analog conversion unit 410. In the resistor string 420, there is a node NB between every two adjacent resistors R2, and the voltage value thereof is between the adjustment voltages V _ADJ1 and V _ADJ2 . Likewise, resistor string 420 can be used to provide multiple partial voltages. After the digital analog conversion unit 410 generates the adjustment voltages V _ADJ1 , V _ADJ2 , the resistor string 420 provides a plurality of output voltages V _OUT2 (1) at its terminals 420A, 420B and all the nodes NB according to the adjustment voltages V _ADJ1 , V _ADJ2 . ~V _OUT2 (Z). According to different requirements, the resistance value and the number of resistors of each resistor R2 in the resistor string 420 can be adjusted accordingly.

The gamma voltage selection unit 430 is coupled to the resistor string 420 for receiving the output voltages V _OUT2 (1) to V _OUT2 (Z) from the resistor string 420, and at the output voltages V _OUT2 (1) to V _OUT2 In (Z), the gamma voltage V _γ' (1) to V _γ' (L) for correcting the image data V _DATA is selected. The selected gamma voltage V _γ' (1) to V _γ' (L) is a portion of the gamma voltage V _γ (1) to V _γ (M).

In one embodiment, the number L of gamma voltages V _γ' (1) to V _γ' (L) is equal to the number Z of output voltages V _OUT2 (1) to V _OUT2 (Z). Please refer to FIG. 6A, which is a schematic diagram showing an embodiment of the gamma voltage selection unit 430 in FIG. 4. As can be seen from FIG. 6A, each input terminal of the gamma voltage selection unit 430 is connected to each output one-to-one, so the output gamma voltage V _γ' (1)~V _γ' (L) is substantially V. _OUT2 (1)~V _OUT2 (Z).

Further, the number L of gamma voltages V _γ' (1) to V _γ' (L) is smaller than the number Z of output voltages V _OUT2 (1) to V _OUT2 (Z). Please refer to FIG. 6B , which is a schematic diagram showing still another embodiment of the gamma voltage selection unit 430 in FIG. 4 . As can be seen from Fig. 6A, in the gamma voltage selecting unit 430, only a part of the input terminals are connected one-to-one to the partial output terminals. Therefore, the output gamma voltages V _γ' (1) to V _γ' (L) are substantially a part of the gamma voltages V _OUT2 (1) to V _OUT2 (Z).

Please return to Figure 4. The reference voltage generating unit 440 receives the reference signal REF and generates a reference voltage V _{R '} according to the reference signal REF. The reference voltage V _{R '} is a reference voltage among the reference voltages V _R (1) to V _R (N). The reference voltage V _R and the gamma voltage V _γ' (1) to V _γ' (L) are used to correct the image data V _DATA .

In addition, the gamma voltage generating unit 400 may further include two operational amplifiers (not shown), one of which is coupled between an output terminal of the digital analog converting unit 410 and the terminal 420A, and the other is coupled to The other end of the digital analog conversion unit 410 is between the terminal 420B. The function of the two operational amplifiers (not shown) is to improve the driving capability of the digital analog conversion unit 410. In the embodiment corresponding to FIG. 5, the two operational amplifiers (not shown) They are used to boost the driving capabilities of the digital analog converters 510A and 510B, respectively.

In summary, the embodiment of the present invention generates a red, green, and blue gamma voltage and a red, green, and blue light reference for correcting red, green, and blue gray scale data by a single gamma voltage driving circuit. The voltage, and the gamma voltage selection unit instead selects a plurality of gamma voltages directly from the plurality of partial voltages to replace the plurality of digital analog converters to convert the plurality of partial voltages into a plurality of gamma voltages instead of the conventional technique. Therefore, the present invention can effectively reduce the production cost of the display device as compared with the prior art. In addition, according to different requirements, the number of red, green, and blue gamma voltages generated by the embodiments of the present invention can also be adjusted correspondingly, which increases the flexibility of the gamma voltage driving circuit.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

200‧‧‧ display device

210‧‧‧ display panel

220‧‧‧ timing controller

230‧‧ ‧ gate driver

240‧‧‧Source Driver

250‧‧‧Gamma voltage drive circuit

251‧‧‧Voltage adjustment unit

252‧‧‧Control unit

253‧‧‧Gamma voltage output circuit

254‧‧‧ storage unit

CODE‧‧‧ adjustment signal

DL‧‧‧ data line

GL‧‧‧ gate line

Px‧‧‧ pixel unit

REF‧‧‧ reference signal

V _γ (1)~V _γ (M)‧‧‧ gamma voltage

V _DATA ‧‧‧ image data signal

V _G (1)~V _G (Y)‧‧‧ gate drive signal

V _IN ‧‧‧ input voltage

V _P (1)~V _P (X)‧‧‧ Grayscale data signal

V _R (1)~V _R (N), V _R' ‧‧‧ reference voltage

T _CON ‧‧‧ Timing Control Signal

TFT‧‧‧Switch unit

Claims (9)

A gamma voltage driving circuit for providing a plurality of gamma voltages and a plurality of reference voltages, the gamma voltage driving circuit comprising: a voltage regulating unit for providing an input voltage; and a control unit for And generating a reference signal and an adjustment signal; and a gamma voltage output circuit for outputting the gamma voltage and the reference voltage, the gamma voltage output circuit comprising: a first resistor string coupled to The voltage regulation unit, the first resistor string includes a plurality of series resistors for providing a plurality of first output voltages according to the input voltage; and a plurality of gamma voltage generating units coupled to the first resistor string And the control unit, the gamma voltage generating units respectively receiving the first output voltage and the reference signal to generate the gamma voltage and the reference voltage, and each of the gamma voltage generating units The method includes: a digital-to-analog converting unit, configured to receive the first output voltages, and according to the first output voltages and the adjustment signals Health a first and a second regulated voltage adjustment voltage; a second series resistor, the series comprising a plurality of resistors for supplying a plurality of second output voltage according to the first and the second adjusting voltage adjustment voltage; and a gamma voltage selection unit is configured to receive the second output voltages to select a plurality of corresponding gamma voltages of the gamma voltages from the second output voltages. The gamma voltage driving circuit of claim 1, wherein the digital analog converting unit comprises a first digital analog converter and a second digital analog converter, wherein the first digital analog converter is configured to receive the first outputs. One portion of the voltage to generate the first regulated voltage, and the second digital analog converter is configured to receive another portion of the first output voltages to generate the second adjusted voltage. The gamma voltage driving circuit of claim 2, wherein each of the gamma voltage generating units further comprises a first operational amplifier and a second operational amplifier for respectively boosting the first digital analog converter And the driving capability of the second digital analog converter. The gamma voltage driving circuit of claim 1, wherein the number of the corresponding gamma voltages is less than or equal to the number of the second output voltages. The gamma voltage driving circuit of claim 1, further comprising a reference voltage generating unit configured to generate a plurality of corresponding reference voltages of the reference voltages according to the reference signal. The gamma voltage driving circuit according to claim 1, wherein the gamma The voltage is a plurality of red gamma voltages, a plurality of green gamma voltages, and a plurality of blue gamma voltages, and the reference voltages are a red light reference voltage, a green light reference voltage, and a blue light reference voltage. The gamma voltage driving circuit of claim 1 further includes a storage unit for storing the reference signal and the adjustment signal. A display device includes: a display panel for displaying a picture according to a plurality of gate driving signals and a plurality of gray level data signals; and a timing controller for generating a timing control signal and an image data a gate driver for receiving the timing control signal to generate the gate driving signals; a source driver for receiving the image data signal and the plurality of gamma voltages ( Gamma voltage and a plurality of reference voltages, wherein the image data signals are adjusted by the gamma voltages and the reference voltages to generate the grayscale data signals; and a gamma voltage driving circuit for providing the gamma a voltage and the reference voltage, the gamma voltage driving circuit comprises: a voltage regulating unit for providing an input voltage; a control unit for generating a reference signal and an adjustment signal; and a gamma voltage output circuit, Used to output the gamma voltages and The gamma voltage output circuit includes: a first resistor string coupled to the voltage regulator unit, the first resistor string comprising a plurality of series resistors for providing a plurality of resistors according to the input voltage An output voltage; and a plurality of gamma voltage generating units coupled to the first resistor string and the control unit, the gamma voltage generating units respectively receiving the output voltages to generate the gamma voltages and the a reference voltage, and each of the gamma voltage generating units includes: a digital-to-analog converting unit for receiving the first output voltages, and according to the first output voltages The adjustment signal generates a first adjustment voltage and a second adjustment voltage; a second resistor string comprising a plurality of series resistors for providing a plurality of second outputs according to the first adjustment voltage and the second adjustment voltage And a gamma voltage selecting unit configured to receive the second output voltages to select a plurality of corresponding gamma of the gamma voltages from the second output voltages Voltage. The display device of claim 8, wherein the display panel is an active matrix organic light-emitting diode (AMOLED) panel.