TWI618047B - Drive circuit of AMOLED display panel - Google Patents

Abstract

A driving circuit for an AMOLED display panel, including an image memory, which has a bit corresponding to a picture element of the display panel; an access control module, which receives an original picture element data and places one of the predetermined bit positions The bit value is stored in the corresponding bit in the image memory, and the value of each bit is sequentially read from the image memory, and the read bit value is output to at least one of the three encoders according to the settings. The encoder that receives the bit value generates one level data according to the bit value, and the two encoders that have not received the bit value generate another two level data, and output to a digital / analog converter, so that The three gradation data are correspondingly converted into three analog signals and output to the display panel, so that the three red, green and blue OLEDs of the picture element are driven according to the three analog signals.

Description

Drive circuit of AMOLED display panel

The invention relates to a driving circuit of a display panel, in particular to a driving circuit of an AMOLED display panel.

An existing AMOLED (Active-matrix Organic Light-Emitting Diode) display panel (hereinafter referred to as a panel) uses a combination of red, green, and blue primary colors to generate colors to be displayed. The main principle is to drive the red, green, and blue OLED (Organic Light-Emitting Diode) that constitutes each picture element on the current panel to emit light, and make the OLED display correspond by controlling the size of the current. The color scale. And the general panel is designed with 256-color grayscale, so each OLED needs to use 8 bits to record 256-color (256 kinds) grayscale data, so for each pixel, as shown in Figure 1, the image source For example, the central processor 11 of the mobile phone 1 needs to generate a primitive data containing 3 grayscale data (a total of 24 bits) and provide it to a driver circuit 12 (generally called DDI (Display Driver IC, display driver IC) ) Wafer). A transmission interface 13 of the driving circuit 12 receives the primitive data and transmits it to the access controller 14, and the access controller 14 stores the primitive data in a primitive data for storing each primitive of the panel 10 In the image memory 15, as shown in FIG. 2, each picture element requires 24 bits of storage space. Therefore, if the resolution of the panel 10 is 1920x1080 pixels, the image memory 15 needs to have 1920x1080x3 bytes of storage space.

After the image memory 15 stores the image data of a display screen, a timing controller 16 of the driving circuit 12 controls the access controller 14 to sequentially read each image data from the image memory 15 and send it to A digital-to-analog converter 17 converts the three grayscale data in each pixel data into three voltage signals and outputs them to the panel 10, so that the three voltage signals are converted into corresponding current signals and Drive the three OLEDs in the corresponding primitive to emit light.

However, in addition to the above-mentioned driving circuit 12, the image memory 15 with 1920x1080x3 bytes is required to correspond to the resolution of the panel 10, so that the size of the driving circuit (chip) 12 cannot be reduced. The controller 14 will continuously write and read a large amount of picture element data to the image memory 15 and consume a lot of power.

Therefore, the object of the present invention is to provide a driving circuit for an AMOLED display panel that can reduce the size of the driving circuit and save power.

Therefore, the driving circuit of the AMOLED display panel of the present invention has MxN picture elements (pixels), each picture element is composed of three OLEDs of red, green, and blue, and the driving circuit sequentially receives MxN (M, N, (N is a positive integer greater than 1) the original primitive data corresponding to the MxN primitives. Each original primitive data includes three original color scale data representing red, green, and blue. Each original color scale data has P (P ≧ 6 and a positive integer) bits; the drive circuit includes: an image memory having MxN bits corresponding to the MxN picture elements; an access control module including the image memory A writing unit and a reading unit electrically coupled, and three encoders respectively corresponding to the three primary colors of red, green, and blue; the writing unit sequentially receives each original picture element data and converts each original picture The bit value of a predetermined bit in the metadata is stored in the bit corresponding to the pixel in the image memory; the reading unit sequentially reads the bit value of each bit from the image memory And output the read bit value to at least one of the three encoders according to the setting The encoder that receives the bit value generates one-level data with P bits according to the bit value, and the other two encoders that do not receive the bit value generate two other levels with P bits Data to compose and output a primitive data including three color scale data; and a digital / analog converter, which sequentially receives the primitive data from the access control module and converts each primitive data The three gradation data in is correspondingly converted into three analog signals and output to the AMOLED display panel, so that the three red, green and blue OLEDs of the picture element are driven according to the three analog signals.

In some embodiments of the present invention, the access control module further includes a transmission interface, which is electrically coupled to the writing unit, and receives the original primitive data and sequentially transmits the data to the writing unit.

In some embodiments of the invention, the access control module further includes a timing controller electrically coupled between the encoders and the digital / analog converter, which outputs the encoders synchronously The three gradation data form a primitive data and output to the digital / analog converter.

In some embodiments of the present invention, the encoder with the received bit value of 1 generates the highest bit of the gradation data according to the bit value as 1, and the received bit value as 0 The encoder generates a bit value of 0 for the highest bit of the gradation data according to the bit value.

In some embodiments of the present invention, the bit value of the highest bit of the gradation data generated by the encoder that has not received the bit value is 0.

In some embodiments of the present invention, the access control module further includes a selector having three input terminals electrically connected to the readout unit and three output terminals correspondingly electrically connected to the encoders , Each of the input terminals accepts the bit value read by the reading unit from each bit of the image memory, and the access control module orders at least one of the three input terminals and the three according to the setting At least one of the output terminals corresponds to the electrical connection, so that the bit value read by the reading unit is output to the corresponding encoder via the output terminal electrically connected to the input terminal, and the other is not electrically connected to the corresponding input terminal The connected output terminal will be grounded so that the highest bit of the gradation data generated by the encoder with a bit value of 1 receives a bit value of 1, and the encoder with a received bit value of 0 generates the color The bit value of all bits of the gradation data is 0, and the bit value of all bits of the gradation data generated by other encoders that have not received the bit value is 0.

The effect of the present invention lies in that the image memory uses only one bit to store the picture element data of each picture element, which can effectively reduce the storage space of the image memory and reduce the volume of the driving circuit, and by using the image memory The read bit value is output to the pre-selected encoder used to generate the gradation data, which determines the pattern color displayed on the panel, and at least only one of the three OLEDs of each pixel of the panel is driven. The panel can effectively reduce power consumption in the case of displaying a single color picture, and achieve the purpose of cost invention.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same number.

Referring to FIGS. 3 and 4, it is an embodiment of the driving circuit of the AMOLED display panel of the present invention, which is applied to a mobile device 2 having an AMOLED display panel 20 (hereinafter referred to as panel 20), such as a mobile phone or a wearable device However, it is not limited to this, that is, the present invention can also be applied to other portable devices, such as notebook computers or tablet computers, or desktop personal computers and other electronic devices with AMOLED display panels.

In this embodiment, the panel 20 has MxN picture elements (M and N are positive integers greater than 1). For example, taking 1920x1080 picture elements as an example, each picture element is composed of three OLEDs of red, green and blue. Moreover, the central processing unit 21 of the mobile device 2 provides 1920x1080 original pixel data of the pixels to be displayed on the panel 20 to the driving circuit 22 of this embodiment, wherein each of the original pixel data includes red and green The three original color scale data of blue and blue, and each original color scale data has P (P ≧ 6 and a positive integer) bits, for example, if red, green, and blue, each color should be divided into 256 from light to deep Color scale (gray scale), the original color scale data of each color needs 8 bits (P = 8) to represent the 0th color scale to the 255th color scale, so the CPU 21 provides the driving circuit 22 with Each original primitive data will have 24 bits.

3 and 4, the driving circuit 22 of this embodiment mainly includes an image memory 23, an access control module 24 and a digital / analog converter 25. The image memory 23 has 1920x1080 bits corresponding to the pixels of the panel 20, that is, the image memory 23 has a storage space of 1920x1080x1 bits. The access control module 24 includes a writing unit 241 and a reading unit 242 electrically coupled to the image memory 23, and three encoders 243, 244, and 245 corresponding to the three primary colors of red, green, and blue, respectively .

Generally, in the normal display mode of the mobile device 2, the access control module 24 will sequentially receive the original primitive data from the central processor 21, and sequentially output to the digital / analog converter 25, so that each The three original color scale data in the original pixel data are converted into corresponding three analog signals (voltage) and output to the panel 20, so that the panel drives the corresponding red, green and blue of the corresponding pixel according to the three analog signals Each OLED emits light to display a picture corresponding to the original image data.

When the mobile device 2 only needs to display a screen composed of a single color, the mobile device 2 can be set or automatically enter a power saving mode. After the mobile device 2 performs the power saving mode, as shown in FIG. 4, the access control The module 24 will instead receive each original primitive data (24 bits) from the central processor 21 in sequence by the writing unit 241, and convert the bit value of a predetermined bit in each original primitive data The bit corresponding to the pixel in the image memory 23 is stored, that is, the first bit of the image memory 23 corresponds to the first pixel of the panel 20, and the second bit of the image memory 23 corresponds to The second primitive of panel 20, and so on. In addition, as shown in FIG. 5, the access control module 24 of this embodiment further includes a transmission interface 246 that is electrically coupled between the central processor 21 and the writing unit 241 for receiving data from the central processor The original primitive data of 21 is transmitted to the writing unit 241 in sequence.

At this time, the above bit value of the predetermined bit is used to represent the corresponding pixel data to be displayed, and the predetermined bit is usually pre-coordinated by the central processor 21 and the access control module 24, and Any bit in the original pixel data can be selected as the predetermined bit. For example, the first bit stores the red pixel data, and the eighth bit stores the green pixel data. Sixteen bits store the blue primitive data. Therefore, if red pixel data is to be output, the writing unit 241 will read the bit value of the first bit (predetermined bit) in each original pixel data and store it in the image memory 23 For the bit corresponding to the pixel, if the green pixel data is to be output, the writing unit 241 will read the bit value of the eighth bit (predetermined bit) in each original pixel data and coexist Into the image memory 23 corresponding to the bit of the picture element; similarly, to output blue picture element data, the writing unit 241 will read the sixteenth bit in each original picture element data The bit value of the cell (predetermined bit) is stored in the bit corresponding to the pixel in the image memory 23. Of course, it is also possible to select only one bit in the original pixel data as the predetermined bit, and use the bit value stored in the predetermined bit to represent the red, green, and blue pixel data.

Therefore, when all or some of the bits of the image memory 23 have been filled with bit values (the rest of the bits will be filled with bit values one after another), as shown in FIG. 4, the access control module 24 orders The reading unit 242 sequentially reads the bit value of each bit from the image memory 23, and outputs the read bit value to at least one of the three encoders 243, 244, 245 according to the setting One, the encoder that received the bit value generates a tone data with 8 bits according to the bit value, for example, if the received bit value is 1, the highest bit of the generated tone data The bit value will be 1, and the bit values of the remaining seven bits may be 1 or 0; the other two encoders that have not received the bit value generate two other color-level data with 8 bits, For example, the bit value of the highest bit of the two gradation data is 0, and the bit values of the remaining seven bits can be 0 or 1; by this, one pixel data containing three gradation data is composed and Output to the digital / analog converter 25.

Specifically, in this embodiment, as shown in FIG. 6, the access control module 24 further includes a selector 247 having three input terminals I1, I1, I3 and three input terminals electrically connected to the readout unit 242 and Three output terminals O1, O2, O3 electrically connected to the three encoders 243, 244, 245, each of the input terminals I1, I1, I3 accepts the bit value output from the reading unit 242, and access control The module 24 causes at least one of the three input terminals I1, I1, I3 to be electrically connected to at least one of the three output terminals O1, O2, O3 according to the setting, so as to pass the received bit value The connected output end is output to the corresponding encoder, and other output ends that are not electrically connected to the corresponding input end will be grounded. In this way, for the encoder that receives the bit value, if the bit value is 1, the bit value of the highest bit of the gradation data generated by it is 1, and the bit values of the remaining seven bits It can be 1 or 0; for other encoders that have not received a bit value, the bit values of all the bits of the gradation data generated by them are all 0.

Therefore, if the mobile device 2 wants the pattern displayed on the panel 20 to be red (single color), the writing unit 241 will read each original pixel from the 1920x1080 original pixel data sequentially output by the central processor 21 The bit value of the first bit (predetermined bit) of the data is stored in the corresponding bit of the image memory 23; and as shown in FIG. 7, the access control module 24 will enable the input terminal of the selector 247 I1 is electrically connected to the output terminal O1, and grounds the output terminals O2 and O3.

In this way, when the reading unit 242 sequentially reads the bit value of each bit of the image memory 23, the read bit value will only be output to the encoder 243 through the selector 247, so if the bit If the value is 1, the encoder 243 will output at least the highest bit value of 1, for example, 8-bit color scale data (representing red) where all bit values are 1, and if the bit value is 0, the encoder 243 Output 8-bit gradation data with all bit values being 0 (representing black), and the other two encoders 244 and 245 respectively output 8-bit gradation data with all bit values being 0 (representing black) . And the access control module 24 composes the above three tone scale data into a picture element data and outputs to the digital / analog converter 25.

In addition, it is worth mentioning that, as shown in FIG. 8, the access control module 24 further includes a timing controller electrically coupled between the three encoders 243, 244, 245 and the digital / analog converter 25 248, which is used to compose the three gradation data synchronously output by the three encoders 243, 244, 245 into a picture element data and then output to the digital / analog converter 25.

Then, the digital-to-analog converter 25 will sequentially receive the primitive data from the access control module 24, and convert the three gradation data in each primitive data into three corresponding analog signals ( Voltage) and output to the panel 20, so that the three red, green, and blue OLEDs of the picture element are driven according to the three analog signals. Therefore, as shown in FIG. 7, when all the bit values of the gradation data output by the encoder 243 are 1, a highest driving voltage will be generated to cause the panel 20 to drive the red OLED in the corresponding picture element to emit light, and the encoding The gradation data output from the devices 244 and 245 will have a minimum or zero volt drive voltage because all the bit values are 0, which is not enough to cause the panel 20 to drive the green and blue OLEDs to emit light; and if the encoder 243 outputs All the bit values of the color scale data are 0, so that the red, green, and blue OLEDs in the corresponding picture element do not emit light but appear black. Therefore, in the screen displayed on the panel 20, the portion with the pattern will be displayed in red, and the area outside the pattern will be displayed in black.

Similarly, if the mobile device 2 wants the panel 20 to display a green pattern (single color), the writing unit 241 will obtain the bit from the eighth bit (predetermined bit) of each original primitive data output by the central processing unit 21 The element value is stored in the corresponding bit of the image memory 23; and as shown in FIG. 9, the access control module 24 electrically connects the input terminal I2 of the selector 247 to the output terminal O2, and causes the output terminals O1, O3 Ground, so that the bit value of each bit sequentially read by the reading unit 242 from the image memory 23 is output to the encoder 244 only through the selector 247, so if the bit value is 1, the encoder 244 will 8-bit gradation data with output bit values of 1 (representing green), if the bit value is 0, the encoder 244 outputs 8-bit gradation data with bit values of 0 (representing black), and The other two encoders 243 and 245 respectively output 8-bit gradation data (representing black) whose bit values are all 0. Then, the access control module 24 outputs each pixel data composed of the above three gradation data to the digital / analog converter 25, so that the digital / analog converter 25 converts the three gradation data in each pixel data It is converted into three corresponding analog signals (voltages) and output to the panel 20, so that the three red, green, and blue OLEDs of the picture element are driven according to the three analog signals. Therefore, in the screen displayed by the panel 20, there are The part of the pattern will show green, and the area outside the pattern will show black.

Similarly, if the mobile device wants the panel 20 to display a blue pattern (single color), the writing unit 241 will obtain from the sixteenth bit (predetermined bit) of each original primitive data output by the central processing unit 21 The bit value is stored in the corresponding bit of the image memory 23; and as shown in FIG. 10, the access control module 24 electrically connects the input terminal I3 of the selector 247 to the output terminal O3, and causes the output terminal O1 O2 is grounded, so that the bit value of each bit sequentially read by the reading unit 242 from the image memory 23 is output to the encoder 245 through the selector 247 only. Therefore, if the bit value is 1, the encoder 245 will output 8-bit gradation data (representing blue) with a bit value of 1, and if the bit value is 0, the encoder 245 will output the bit values. The 8-bit gradation data (representing black) is 0, and the other two encoders 243, 244 respectively output the 8-bit gradation data (representing black) with bit values of 0. The access control module 24 then outputs each pixel data composed of the above-mentioned three gradation data to the digital / analog converter 25, so that the digital / analog converter 25 converts the three gradations in each pixel data The data is converted into three corresponding analog signals (voltages) and output to the panel 20, so that the three red, green, and blue OLEDs of the picture element are driven according to the three analog signals. Therefore, in the screen displayed by the panel 20, The part with the pattern will show blue, and the area outside the pattern will show black.

In addition, if the mobile device 2 wants the panel 20 to display a white pattern, the writing unit 241 obtains another predetermined bit of each original pixel data output from the central processor 21, for example, the twenty-third bit The value is stored in the corresponding bit of the image memory 23; and as shown in FIG. 11, the access control module 24 makes the input terminals I1, I2, I3 of the selector 247 and the output terminals O1, O2, O3 correspondingly electrically connected , So that the bit value of each bit sequentially read by the reading unit 242 from the image memory 23 is output to the encoders 243, 244, and 245 through the selector 247, so if the bit value is 1, the encoder 243, 244, and 245 will simultaneously output 8-bit gradation data with bit values of 1 (three colors are mixed into white), and if the bit value is 0, the encoders 243, 244, and 245 will simultaneously output bits 8-bit gradation data (representing black) whose values are all 0. Then, the access control module 24 outputs each pixel data composed of the above-mentioned three gradation data to the digital / analog converter 25, so that the digital / analog converter 25 converts the three gradation data in each pixel data It is converted into three corresponding analog signals (voltage) and output to the panel 20, so that the three red, green, and blue OLEDs of the picture element are driven according to the three analog signals to emit light. Therefore, in the screen displayed by the panel 20, The part with the pattern will display white, and the area outside the pattern will display black.

In addition, if the pattern displayed on the panel 20 is to be a mixture of two colors of red, green, and blue, as shown in FIG. 12, the access control module 24 may enable two input terminals of the selector 247, for example I1, I2 are electrically connected correspondingly to the output terminals O1, O2, and the output terminal O3 is grounded, so that the bit value of each bit sequentially read by the reading unit 242 from the image memory 23 is output to the encoder through the selector 247 243, 244, so if the bit value is 1, the encoders 243, 244 will output 8-bit gradation data (red and green mixed color) with bit values of 1, and if the bit value is 0, Then, the encoders 243 and 244 output 8-bit gradation data (representing black) with bit values of 0, and the other encoder 245 outputs 8-bit gradation data (representing black) with bit values of 0. . Then, the access control module 24 outputs each pixel data composed of the above three gradation data to the digital / analog converter 25, so that the digital / analog converter 25 converts the three gradation data in each pixel data It is converted into three corresponding analog signals (voltages) and output to the panel 20, so that the three red, green, and blue OLEDs of the picture element are driven according to the three analog signals, by which the image displayed on the panel 20 , The part with the pattern will display the color mixed with red and green, and the area outside the pattern will show black.

In summary, it can be seen that the image memory 23 of this embodiment only uses one bit to store the image data of one image element. Compared with the conventional image memory, it needs to use eight bits to store the image data of one image element. The image memory 23 is reduced to only 1/24 of the storage space of the image memory, which can effectively reduce the size and cost of the drive circuit 22 (DDI chip). In this embodiment, by controlling the bit value read by the reading unit 242 to output to one of the three encoders 243, 244, and 245, the pattern color to be displayed on the panel 20 is determined, and each of the panel 20 is made At least only a single OLED emits light in the picture element. Compared with the conventional panel, the three (three-color) OLEDs in the picture element emit light at the same time to save power. In addition to maintaining the picture quality and achieving the effect of power saving.

In addition, this embodiment can also produce different power saving effects according to the luminous efficiency of OLEDs of different colors. For example, under normal circumstances, the luminous efficiency of a red OLED is 25%, the luminous efficiency of a green OLED is 10%, and the luminous efficiency of a blue OLED The efficiency is 45%. Therefore, if you want to further save power, you can choose to make the blue OLED in the picture element of the panel 20 emit light, and the red and green OLED do not emit light, to further improve the power saving efficiency.

In summary, the present invention uses the image memory 23 to store only one bit of image data for each picture element, which can effectively reduce the storage space of the image memory 23 and reduce the volume of the drive circuit 22, and by reducing The bit values read from the image memory 23 are output to a pre-selected encoder for generating gradation data, which determines the color of the pattern displayed on the panel 20, and enables three OLEDs for each pixel of the panel 20 Only at least one of them is driven, so that the panel 20 can effectively reduce power consumption in the case of displaying a single color picture, so it does achieve the purpose of reducing the size of the driving circuit and saving power.

However, the above are only examples of the present invention, and the scope of implementation of the present invention cannot be limited by this, any simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the patent specification are still classified as Within the scope of the invention patent.

1‧‧‧Mobile
10‧‧‧AMOLED display panel
11‧‧‧ CPU
12‧‧‧Drive circuit (DDI chip)
13‧‧‧Transmission interface
14‧‧‧Access controller
15‧‧‧Image memory
16‧‧‧sequence controller
17‧‧‧Digital / Analog Converter
2‧‧‧Mobile device
20‧‧‧AMOLED display panel
21‧‧‧ CPU
22‧‧‧Drive circuit (DDI chip)
23‧‧‧ Image memory
24‧‧‧Access control module
25‧‧‧Digital to analog converter
241‧‧‧ Writing unit
242‧‧‧Reading unit
243, 244, 245
246‧‧‧Transmission interface
247‧‧‧selector
248‧‧‧sequence controller
I1, I2, I3 ‧‧‧ input
O1, O2, O3 ‧‧‧ output

Other features and functions of the present invention will be clearly presented in the embodiments with reference to the drawings, in which: FIG. 1 is a circuit block diagram illustrating a conventional driving circuit applied to a mobile phone; FIG. 2 is a schematic diagram , Showing the storage space required for a primitive data; FIG. 3 is a circuit block diagram illustrating an embodiment of the driving circuit of the present invention applied to a mobile device; FIG. 4 is a circuit block diagram illustrating the memory included in this embodiment Take the components included in the control module; FIG. 5 is a circuit block diagram illustrating the transmission interface of this embodiment is electrically coupled between the central processing unit and the writing unit; FIG. 6 is a circuit block diagram illustrating this embodiment Is electrically coupled between the readout unit and the three encoders; FIG. 7 is a circuit block diagram similar to FIG. 6, illustrating that the selector of this embodiment electrically connects the readout unit and the red encoder; FIG. 8 is A circuit block diagram illustrating that the timing controller of this embodiment is electrically coupled between three encoders and a digital / analog converter; FIG. 9 is a circuit block diagram similar to FIG. 6, illustrating the selector circuit of this embodiment. Connect read Fig. 10 is a circuit block diagram similar to Fig. 6 illustrating the selector electrically connecting the readout unit and the blue encoder of this embodiment; Fig. 11 is a circuit block diagram similar to Fig. 6 illustrating the implementation The selector of the example is electrically connected to the readout unit and three encoders; and FIG. 12 is a circuit block diagram similar to FIG. 6, illustrating that the selector of this embodiment electrically connects the readout unit to the red encoder and the green encoder.

2‧‧‧Mobile device

20‧‧‧AMOLED display panel

21‧‧‧ CPU

22‧‧‧Drive circuit (DDI chip)

23‧‧‧ Image memory

24‧‧‧Access control module

25‧‧‧Digital to analog converter

Claims (6)

A driving circuit of an AMOLED display panel, the AMOLED display panel has MxN picture elements, each picture element is composed of three OLEDs of red, green, and blue, and the driving circuit sequentially receives MxN picture elements corresponding to the MxN picture elements Primitive data, each original primitive data includes three original color scale data representing red, green, and blue, and each original color scale data has P (P ≧ 6 and positive integer) bits; the driving circuit includes : An image memory with MxN bits corresponding to the MxN picture elements; an access control module including a writing unit and a reading unit electrically coupled to the image memory, and each Three encoders corresponding to the three primary colors of red, green and blue; the writing unit sequentially receives each original pixel data and stores the bit value of a predetermined bit in each original pixel data into the image memory The bit corresponding to the picture element in the volume; the reading unit sequentially reads the bit value of each bit from the image memory, and outputs the read bit value to the three according to the setting At least one of the encoders makes the encoding of the received bit value According to the bit value, one color scale data with P bits is generated, and the other two encoders that have not received the bit value generate two other color scale data with P bits, to form three color levels A primitive data of the data and output; and a digital / analog converter, which sequentially receives the primitive data from the access control module, and correspondingly converts the three gradation data in each primitive data The three analog signals are outputted to the AMOLED display panel, so that the three red, green and blue OLEDs of the picture element are driven according to the three analog signals. The driving circuit of the AMOLED display panel according to claim 1, wherein the access control module further includes a transmission interface, which is electrically coupled to the writing unit, and receives the original picture element data and sequentially transmits to the Write unit. The driving circuit of the AMOLED display panel according to claim 1, wherein the access control module further includes a timing controller electrically coupled between the encoders and the digital / analog converter, which encodes the same The three gradation data synchronously output by the device form a primitive data and output to the digital-to-analog converter. The driving circuit of the AMOLED display panel according to claim 1, wherein the encoder that receives the bit value of 1 generates the highest bit of the gradation data according to the bit value as 1, and receives the bit The encoder with a value of 0 generates a bit value of 0 for the highest bit of the gradation data generated from the bit value. The driving circuit of the AMOLED display panel according to claim 4, wherein the bit value of the highest bit of the gradation data generated by the encoder that has not received the bit value is 0. The drive circuit of the AMOLED display panel according to claim 1, wherein the access control module further includes a selector having three input terminals electrically connected to the readout unit and three corresponding electrical circuits corresponding to the encoders Connected output terminals, each of the input terminals accepts the bit value read by the reading unit from each bit of the image memory, and the access control module orders at least one of the three input terminals according to the setting Electrically connected to at least one of the three output terminals to output the bit value read by the reading unit to the corresponding encoder via the output terminal electrically connected to the input terminal, and the other is not corresponding to The input of the input terminal is electrically connected to the ground, so that the highest bit of the gradation data generated by the encoder with a bit value of 1 receives a bit value of 1, and the encoder with a bit value of 0 received The bit value of all bits of the generated color scale data is 0, and the bit value of all bits of the color scale data generated by other encoders that have not received the bit value is 0.