TWI698848B - Source drive circuit, display device and information processing device - Google Patents

Abstract

A source driving circuit includes a plurality of source driving units, each of the source driving units has: a disabling data buffer unit, which is enabled or disabled according to the control of a consistent energy control signal to display data Buffer operation; and a disableable channel driver having an input, a control, and an output, wherein the input is coupled to the output of the disable data buffer unit, and the control is Coupled with the enabling control signal, wherein when the enabling control signal presents an active state, the output terminal outputs a pixel driving voltage, and the pixel driving voltage is generated according to a display data, and when the enabling control signal When the energy control signal presents an inactive state, the output terminal is disabled.

Description

Source drive circuit, display device and information processing device

The present invention relates to the technical field of display panel driving, in particular to a source driving circuit and a display device.

In a general display panel, a gate driving circuit and a source driving circuit cooperate to drive a pixel array to present a picture on a display screen. FIG. 1 shows a circuit block diagram of a conventional source driving circuit. As shown in FIG. 1, the conventional source drive circuit includes: y shift registers 11', y data registers 12', y display data loaders 13', and y channel drivers 14'; where y is An integer greater than 1, the y shift registers 11' transmit an enable signal (En1, En2, …Eny) to each of them according to a shift clock signal (Shift clock) and a start pulse signal (Start pulse). A corresponding data register 12' enables y data registers 12' to sequentially load a corresponding display data from a data bus; y display data loaders 13' are controlled by a data load signal The y display data output by the y data registers 12' are sent to the y channel drivers 14'; and the y channel drivers 14' generate y analog voltages based on the y display data to drive the display panel 2'for display One picture.

Please refer to FIG. 2, which shows a structural diagram of another conventional source driving circuit. As shown in FIG. 2, the conventional source driving circuit includes a plurality of source driving units 1', and each source driving unit 1'includes a shift register 11' and a data buffer 12' as shown in FIG. , A display data loader 13' and a channel driver 14'. Generally speaking, when the display panel 2'has a lower resolution, as shown in FIG. 2, the conventional source driving circuit only needs to provide a local source driving unit 1'to connect to the display panel 2'.

However, when the choice of resolution is limited, if the resolution of the source image 3'does not match the set resolution of the display panel 2', an application processor (AP) will activate the relevant image The processing function adjusts the source image so that it can adapt to the set resolution of the display panel 2'.

In addition, when the image processing function performs the image processing procedure on the source image 3', since a part of the source image 3'is not used, errors or errors may occur in the image processing algorithm. In addition, during the normal operation of the source driving circuit, the display data of the unused source image 3'will become so-called redundant data. It must be noted that this redundant data will not only occupy the buffer space of each source driver unit 1', but also cause the effective display data to fail one after another, thus causing clock delay or data congestion, resulting in failure of the system's main frequency. Reduce the overall power consumption of the source drive circuit is too high.

Therefore, there is an urgent need for a novel source driving circuit in the art.

The main purpose of the present invention is to provide a source drive circuit, which can be used without the need for application processor (AP), algorithm of intellectual property (Intellectual property, IP), system clock, chip package structure (COF or COP) provides a flexible resolution setting mechanism by enabling/disabling the channel when changing the design.

To achieve the above objective, a source drive circuit is proposed, which includes a plurality of source drive units, each of which has:

A data cache unit that can be disabled, which enables or disables a display data cache operation based on the control of the consistent energy control signal; and

A disableable channel driver has an input terminal, a control terminal and an output terminal, wherein the input terminal is coupled to the output of the disableable data buffer unit, and the control terminal is connected to the enable The control signal is coupled, wherein when the enable control signal presents an active state, the output terminal outputs a pixel driving voltage, and the pixel driving voltage is generated according to a display data, and when the enable control signal presents In a non-functioning state, the output is disabled.

In order to achieve the above objective, the present invention provides a source driving circuit, which has:

A channel enabling signal generating unit for generating Y channel enabling signals according to a channel enabling command and a first shift clock signal, Y is an integer greater than 1;

Y shift registers, wherein the first shift register is coupled to a start pulse signal and a second shift clock signal, and the second to Yth shift registers are all coupled to the second Shift clock signal;

Y selection units, wherein each of the selection units is coupled to the corresponding channel enable signal and the shift register, so that the N+1th shift register and the N+1th selection unit are both Coupled to a first signal transmitted from the Nth selection unit, and N is at least 1;

Y data registers, wherein each of the data registers is coupled to a data bus and a second signal sent from the selection unit;

Y display data loaders, wherein each of the display data loaders is coupled to a data load signal, the data register, and the corresponding channel enable signal; and

Y channel drivers, wherein each of the channel drivers is coupled to the data buffer and the corresponding channel enable signal.

In an embodiment, the channel enable signal generation unit includes Y D flip-flops, wherein the first D flip-flop is coupled to the channel enable command and the first shift clock signal, and the N+1th The D flip-flop is coupled to the first shift clock signal and the channel enable signal transmitted from the Nth D flip-flop.

In an embodiment, each of the selection units includes: a multiplexer, wherein the first multiplexer is coupled to the first channel enable signal, and one of the first shift registers outputs Signal and the start pulse signal, and the N+1th said multiplexer is coupled to an output signal of the Nth said multiplexer, the N+1th said channel enabling signal and the N+1th said multiplexer The output signal of the shift register, and the N+1th shift register is simultaneously coupled to the output signal of the Nth multiplexer.

In a possible embodiment, each of the selection units further includes: an and gate, wherein the Nth and gate is coupled to the Nth channel enable signal and the output signal of the Nth shift register , And transmit the second signal to the Nth data buffer.

In a possible embodiment, each of the shift registers receives the second shift clock signal through a buffer, and some of the data buffers are coupled to the data through a delay cell Busbar.

In one embodiment, the channel enable signal generating unit receives the channel enable command in a non-display interval of an image packet, and the non-display interval is a vertical back porch (VBP) or a vertical front porch (Vertical Front Porch, VFP).

In a possible embodiment, the source driving circuit further includes:

Y/2 multiplexers, Y is an even number, wherein the input end of each multiplexer is coupled to the output end of the Nth data register and the N+1th data register, and each The output terminal of the multiplexer is coupled to a channel driver for transmitting a display data of the Nth data register or the N+1th data register to the channel according to a selection signal Drive; and

Y/2 OR gates, wherein the input terminal of each OR gate is coupled to the output terminal of the Nth D flip-flop and the N+1th D flip-flop, and the output terminal of each OR gate A channel driver is coupled to generate and transmit a channel control signal to the Nth D flip-flop and the N+1th D flip-flop transmitted by the two channel enable signals Channel driver.

In addition, the present invention also provides an embodiment of a display device, which includes a display panel and a display control chip, wherein the display control chip has the aforementioned source driving circuit.

The present invention also provides an embodiment of an information processing device, which has a display panel and a display control chip, wherein the display control chip has the aforementioned source driving circuit.

In possible embodiments, the information processing device may be a smart phone, a tablet computer, a notebook computer, an all-in-one computer, a smart watch, or an access control device.

In order to enable your reviewer to further understand the structure, features, purpose, and advantages of the present invention, the drawings and detailed descriptions of preferred embodiments are attached as follows.

First embodiment

FIG. 3 shows a circuit structure diagram of the first embodiment of the source driving circuit of the present invention. As shown in FIG. 3, the source driving circuit of the present invention is used to couple to the display driving end of a display panel 2, and includes: a channel enable signal generating unit 10, Y shift registers 11, and Y selection units 15 , Y data registers 12, Y display data loaders 13, and Y channel drivers 14. The channel enable signal generation unit 10 is used to generate Y channel enable signals (C_En1, C_En2,..., C_EnY) according to a channel enable command (CEn bits) and a first shift clock signal (CEn shift clock). ). According to the design of the present invention, the first shift register 11 is coupled to a start pulse signal (Start pulse) and a second shift clock signal (Shift clock), and the second shift register 11 to the second shift register The Y shift registers 11 are all coupled to the second shift clock signal.

In the first embodiment, the channel enabling signal generating unit 10 includes Y D flip-flops 101. Of course, under the premise of the same functional design, the channel enable signal generation unit 10 may not consist of Y D flip-flops 101, as long as it can generate Y channel enable signals after receiving the channel enable command (CEn bits). can. As shown in FIG. 3, the first D flip-flop 101 is coupled to the channel enable command (CEn bits) and the first shift clock signal (CEn shift clock), and the N+1th D flip-flop 101 Then, it is coupled to the first shift clock signal and the channel enable signal transmitted from the Nth D flip-flop 101, and N is at least 1. In addition, each of the selection units 15 is coupled to the corresponding channel enable signal and the shift register 11, so that the N+1 th shift register 11 and the N+1 th selection unit 15 are both It is coupled to a first signal S1 transmitted from the Nth selection unit 15.

FIG. 3 illustrates an exemplary configuration of each of the selection units 15, that is, each of the selection units 15 includes a multiplexer 151 and an AND gate 152. Among the Y multiplexers 151, the first multiplexer 151 is coupled to the first channel enable signal, one of the output signals of the first shift register 11, and the start pulse signal, and the N+1th multiplexer The multiplexer 151 is coupled to an output signal of the Nth multiplexer 151, the N+1th channel enable signal, and the output signal of the N+1th shift register 11; and, the N+1th shift register 11 is also coupled to the output signal of the N-th multiplexer 151 at the same time. On the other hand, among Y AND gates 152, the Nth AND gate 152 is coupled to the Nth channel enable signal and the Nth output signal of the shift register 11, and transmits the selection unit A second signal S2 of 15 to the Nth data register 12. In the first embodiment, each of the data registers 12 is also coupled to a data bus.

Furthermore, each of the display data loaders 13 is coupled to a data load signal, the data register 12, and the corresponding channel enable signal, and each of the channel drivers 14 is coupled to the data register 13 and The channel enable signal corresponding thereto. It must be emphasized that the shift register 11, the data register 12, the display data loader 13, and the channel driver 14 shown in FIG. 3 are all the main circuit units of the conventional source driving circuit. The circuit function will not be repeated. In particular, the present invention adds the channel enable signal generating unit 10 to the source drive circuit to generate Y channel enable signals according to a channel enable command and a first shift clock signal, thereby The Y channel enable signals respectively determine whether each data register 12, each display data loader 13 and each channel driver 14 are enabled. At the same time, the present invention adds Y selection units 15 in the source driving circuit to determine whether each shift register 11 is skipped or not used (Bypass).

FIG. 4 shows a working timing diagram of multiple selection units of the source driving circuit of the present invention. When referring to Figures 3 and 4 at the same time, it should be understood that among the 6 channels (Channel) of the source drive circuit, the first, the third, and the fourth are activated by the corresponding channel. Closed. The reason is that the first and gate 152, the third and gate 152, and the fourth and gate 152 all output low-level signals, indicating that the first channel enable signal (C_En1) transmitted from the channel enable signal generation unit 10, The third channel enable signal (C_En3) and the fourth channel enable signal (C_En4) are both low level signals. At this time, it can be seen from Figure 3 that the first display data loader 13, the third display data loader 13, and the fourth display data loader 13 will also be controlled by the corresponding channel enable signal. Enable its display data loading function. At the same time, the third shift register 11 and the fourth shift register 11 will be skipped based on the control of the selection unit 15 (Bypass). It is worth noting that, because the third shift register 11 and the fourth shift register 11 are skipped (Bypass), the second channel driver 14, the fifth channel driver 14, and the sixth channel driver 14 The output display drive signals will follow one by one, and there will be no clock delay or data congestion due to unused channels in the middle.

It is supplemented that the source driving circuit of the present invention can receive the channel enable command (CEn bits) at any point in time. On the other hand, electronic engineers who are familiar with the design and manufacture of source driver chips must know that in the process of receiving display commands on a source driver chip, they generally experience Power-on sequence, Blanking-on, display, and Blanking-off. , And Power-off sequence these time intervals, including Power-on sequence, Power-off sequence and display interval (Vertical Front Porch, VFP) and Vertical Back Porch (VBP) All belong to the non-display interval. Therefore, the channel activation signal generating unit 10 can receive the channel activation command in a non-display interval of an image packet, and the non-display interval is a vertical back porch (VBP) and/or a vertical front porch (VFP) . Further, under the premise of saving power consumption, after the source driving circuit of the present invention is powered on, the channel enabling signal generating unit 10 can be made to receive the channel enabling command once. However, considering the stability of the circuit operation, it is recommended to transmit the channel activation command to the channel activation signal generating unit 10 in the vertical back porch (VBP) and vertical front porch (VFP) of each display frame.

After understanding the design spirit of the present invention, it should be inferred that when the Nth shift register 11 has an output signal and the Nth channel enable signal (C_EnN) is at a high level, the Nth and gate ( The AND gate 152 will output a high level signal to activate the Nth data buffer 12. Therefore, under the premise of the same functional design, each of the selection units 15 may actually not include the gate 152. Simply put, each of the selection units 15 only includes a multiplexer 151 for selecting to skip (or span) a specific shift register 11, and at this time, the Nth channel enable signal (C_EnN) is directly coupled To the Nth data register 12 to determine whether the data register 12 is enabled or not.

Second embodiment

In order to reduce the number of channels of the source driver chip and simplify the circuit area of the source driver chip, many current source driver chips integrate a 1:12 or 1:6 channel switching unit (Source channel Multiplexing). In consideration of reducing the number of channels, the present invention also provides the second embodiment of the source driving circuit. FIG. 5 shows a circuit structure diagram of the second embodiment of the source driving circuit of the present invention. In the second embodiment, the source driving circuit of the present invention further includes Y/2 multiplexers 161 and Y/2 OR gates 162. The input end of each multiplexer 161 is coupled to the output end of the Nth data buffer 13 and the N+1th data buffer 13, and the output end of each multiplexer 161 Coupled to a channel driver 14 for transmitting the display data of the Nth data register 13 or the N+1th data register 13 to the channel driver 14 according to a select signal (SEL) . On the other hand, the input terminal of each OR gate 162 is coupled to the output terminals of the Nth D flip-flop 101 and the N+1th D flip-flop 101, and the output terminal of each OR gate 16 A channel driver 14 is coupled to generate and transmit a channel control according to the two channel enable signals transmitted by the Nth D flip-flop 101 and the N+1th D flip-flop 101 Signal to the channel driver 14.

Of course, in a feasible embodiment, the or gate 162 can also be replaced by an and gate. Furthermore, considering that the Nth multiplexer 151 may cause the delay of the N+1th shift register 11 receiving the second shift clock signal and the start pulse signal (Start pulse), each shifter can be The bit register 11 receives the second shift clock signal through a buffer; at the same time, the data buffer 12 can also be coupled to the data bus through a delay cell. Further, at the same time, it can also be considered that when the external controller outputs the display data (R, G, B), the second shift clock signal (Shift clock) of the shift register 11 and the data bus of the data register 12 There is a margin in the phase delay of the (Data Bus), so as to balance the clock delay (Delay) of the circuit unit that may be caused by the channel enable signal. In this way, any possible clock delays can be balanced, which is beneficial to the more accurate operation of the source driving circuit of the present invention.

It can be seen from the above description that the source driving circuit of the present invention includes a plurality of source driving units, and is characterized in that each of the source driving units has: a disabling data buffer unit, which is controlled by a consistent energy The control enables or disables a display data buffer operation; and a disabling channel driver with an input terminal, a control terminal and an output terminal, wherein the input terminal is the disabling data buffer unit The output is coupled to the control terminal and the enable control signal is coupled, wherein, when the enable control signal presents an active state, the output terminal outputs a pixel driving voltage, and the pixel driving voltage is Generated according to a display data, and when the enabling control signal presents an inactive state, the output terminal is disabled. In this way, the above system has completely and clearly explained the source driving circuit of the present invention; and from the above, it can be seen that the present invention has the following advantages:

(1) The present invention adds a channel enable signal generation unit 10 and Y selection units 15 to a source driving circuit, so that the channel enable signal generation unit 10 can be received and transmitted from an external controller (Controller) One channel enable command (CEn bits) to generate Y channel enable signals (C_En1, C_En2,..., C_EnY). In this way, during the normal operation of the source driving circuit of the present invention, if the resolution of the source image does not match the set resolution of the display screen, if part of the active image is not used, Then, the channel enable signal can be used to decide to skip the specific shift register 11 in the source drive circuit and not used (Bypass), and the channel enable signal can be used to respectively select and close the corresponding data register 12 and display data loading The display driver 13 and the channel driver 14 make the display driving signals output by each channel of the source driving circuit follow one after another, without clock delay or data congestion due to unused channels.

(2) Furthermore, the present invention also provides a display device including a display panel and a display control chip, wherein the display control chip has the source driving circuit of the present invention as described above.

(3) Furthermore, the present invention also provides an information processing device, which has a display panel and a display control chip, wherein the display control chip has the source driving circuit of the present invention as described above. In addition, the information processing device is an electronic device selected by the group consisting of a smart phone, a tablet computer, a notebook computer, an all-in-one computer, a smart watch, and an access control device.

It must be emphasized that the foregoing disclosures in this case are preferred embodiments, and any partial changes or modifications that are derived from the technical ideas of this case and are easily inferred by those who are familiar with the art will not deviate from the patent of this case. Right category.

In summary, regardless of the purpose, means and effect of this case, it is shown that it is very different from the conventional technology, and its first invention is suitable for practicality, and it does meet the patent requirements of the invention. I sincerely ask the examiner to check it out and grant the patent as soon as possible. Society is for the best prayer.

<The present invention>

2: display panel

10: Channel enable signal generation unit

11: shift register

12: Data buffer

13: Display data loader

14: Channel driver

15: Select unit

151, 161: Multiplexer

152: and gate

162: or gate

＜Acquaintances＞

1’: Source drive unit

2’: Display panel

3’: Source image

11’: shift register

12’: Data buffer

13’: Display data loader

14’: Channel Driver

FIG. 1 is a circuit block diagram of a conventional source driving circuit. Fig. 2 is a diagram of the operation architecture of a conventional source drive circuit. FIG. 3 is a circuit structure diagram of the first embodiment of the source driving circuit of the present invention. Fig. 4 is a working sequence diagram of multiple selection units of the source drive circuit of the present invention. FIG. 5 is a circuit structure diagram of the second embodiment of the source driving circuit of the present invention.

2: display panel

10: Channel enable signal generation unit

11: shift register

12: Data buffer

13: Display data loader

14: Channel driver

15: Select unit

151: Multiplexer

152: and gate

101: D flip-flop

Claims (9)

A source driving circuit has: a channel enable signal generation unit for generating Y channel enable signals according to a channel enable command and a first shift clock signal, Y is an integer greater than 1, and Y shifts Register, wherein the first shift register is coupled to a start pulse signal and a second shift clock signal, and the second to Yth shift registers are all coupled to the second shift clock signal Y selection units, wherein each of the selection units is coupled to the corresponding channel enable signal and the shift register, so that the N+1th shift register and the N+1th selection unit Are coupled to a first signal transmitted from the Nth selection unit, and N is at least 1; Y data registers, wherein each of the data registers is coupled to a data bus and transmitted from the selection unit A second signal; Y display data loaders, wherein each of the display data loaders is coupled to a data load signal, the data register and the corresponding channel enable signal; and Y channel drivers, Each of the channel drivers is coupled to the data buffer and the corresponding channel enable signal. According to the source driving circuit described in claim 1, wherein the channel enable signal generating unit includes Y D flip-flops, wherein the first D flip-flop is coupled to the channel enable command and the first shift A bit clock signal. The N+1th D flip-flop is coupled to the first shift clock signal and the channel enable signal transmitted from the Nth D flip-flop. According to the source drive circuit described in claim 1, wherein each of the selection units includes: a multiplexer, wherein the first multiplexer is coupled to the first channel enable signal, the first An output signal of one of the shift registers and the start pulse signal, and the N+1th multiplexer is coupled to the output signal of one of the Nth multiplexers, and the N+1th The channel enable signal and the output signal of the N+1th said shift register, and the N+1th said shift register are simultaneously coupled to the output signal of the Nth said multiplexer. According to the source driving circuit described in item 3 of the scope of patent application, each of the selection units further includes: an AND gate, wherein the Nth and gate is coupled to the Nth channel enable signal and the Nth The output signal of one of the shift registers, and the second signal is transmitted to the Nth said data register. According to the source driver circuit described in claim 1, wherein each of the shift registers receives the second shift clock signal through a buffer, and some of the data buffers pass through a delay circuit And coupled to the data bus. According to the source driver circuit described in claim 1, wherein the channel enable signal generating unit receives the channel enable command in a non-display interval of an image packet, and the non-display interval is a vertical back corridor ( Vertical Back Porch, VBP) or a vertical front porch (Vertical Front Porch, VFP). The source drive circuit described in item 2 of the scope of the patent application further includes: Y/2 multiplexers, Y is an even number, wherein the input end of each multiplexer is coupled to the Nth data register And the output end of the N+1th said data register, and the output end of each of the multiplexers is coupled to one of the channel drivers, and is used to connect the Nth said data register or A display data of the N+1th data register is sent to the channel driver; and Y/2 OR gates, wherein the input end of each OR gate is coupled to the Nth D flip-flop and the Nth +1 output terminals of the D flip-flops, and each output terminal of the OR gate is coupled to one of the channel drivers for triggering according to the Nth D flip-flop and the N+1th D trigger The two channel enable signals transmitted by the device generate and transmit a channel control signal to the channel driver. A display device includes a display panel and a display control chip, wherein the display control chip has the source driving circuit as described in any one of the first to seventh patent applications. An information processing device, which has a display panel and a display control chip, wherein the display control chip has the source drive circuit as described in any one of items 1 to 7 of the scope of patent application, and the information processing device It is an electronic device selected by the group consisting of smart phones, tablet computers, notebook computers, all-in-one computers, smart watches and access control devices.

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