Display control circuit and display control method

Abstract

The present disclosure provides a display control circuit and a display control method. The display control circuit includes a storage unit, a control register, a zone dimming control register, and a microcontroller unit. The storage unit is configured to store a plurality of predefined LDC setting data. The control register is configured to store a first mode setting value. The zone dimming control register is configured to store the LDC setting data applied synchronously with a frame synchronization signal. The microcontroller unit is coupled to the control register and the zone dimming control register. The microcontroller unit is configured to read a first predefined LDC setting data of the plurality of predefined LDC setting data stored in the storage unit according to the first mode setting value, and write the first predefined LDC setting data into the zone dimming control register.

Description

Technical Field

[0001] This disclosure relates to a control circuit, and more particularly to a display control circuit and a display control method. Background Technology

[0002] Traditional local dimming relies on a fixed set of parameters tailored to a specific display and backlight, limiting its effectiveness across different scenes or images. To address this, traditional methods involve a front-end system (e.g., a microcontroller unit, system-on-a-chip, or electronic control unit) performing large-scale parameter adjustments to the driver integrated circuit based on the scene. However, the complex command load consumes significant communication bus bandwidth, increasing the risk of command errors. Furthermore, because front-end commands are often not synchronized with video frames and occur randomly in the active and blanking regions, they can lead to backlight anomalies such as excessive brightness, darkness, or flickering. In automotive applications, these issues result in serious driving safety problems. Summary of the Invention

[0003] The display control circuit and display control method disclosed herein can achieve rapid switching between multiple dimming operation modes.

[0004] The display control circuit disclosed herein includes a storage unit, a control register, a local dimming control register, and a microcontroller unit. The storage unit stores multiple predefined LDC setting data. The control register stores a first mode setting value. The local dimming control register stores LDC setting data applied synchronously with a frame synchronization signal. The microcontroller unit is coupled to the control register and the local dimming control register, and is used to read the first predefined LDC setting data from the multiple predefined LDC setting data stored in the storage unit according to the first mode setting value, and write the first predefined LDC setting data into the local dimming control register.

[0005] The display control method disclosed herein includes the following steps: storing a first mode setting value via a control register; storing LDC setting data applied synchronously with a frame synchronization signal via a local dimming control register; and reading first predefined LDC setting data from a plurality of predefined LDC setting data stored in the storage unit according to the first mode setting value via a microcontroller unit, and writing the first predefined LDC setting data into the local dimming control register via the microcontroller unit. The local dimming control register is used to store predefined LDC setting data applied synchronously with a frame synchronization signal.

[0006] Based on the above, according to the display control circuit and display control method disclosed herein, the microcontroller unit can quickly write predefined LDC setting data into the local dimming control register to achieve rapid switching between multiple local dimming operation modes.

[0007] To make the above content easier to understand, several embodiments accompanied by the accompanying drawings are described in detail below. Attached Figure Description

[0008] Figure 1 This is a circuit diagram of a display control circuit according to an embodiment of the present disclosure;

[0009] Figure 2 This is a flowchart of a display control method according to an embodiment of the present disclosure;

[0010] Figure 3 Based on this disclosure Figure 1 A schematic diagram of the relevant signals in the embodiment;

[0011] Figure 4 This is a circuit diagram of a display control circuit according to an embodiment of the present disclosure;

[0012] Figure 5 Based on this disclosure Figure 4 A schematic diagram of the relevant signals in the embodiment;

[0013] Figure 6 Based on this disclosure Figure 4 Another schematic diagram of the relevant signals in the embodiment;

[0014] Figure 7 This is a circuit diagram of a display control circuit according to an embodiment of the present disclosure;

[0015] Figure 8 Based on this disclosure Figure 7 A schematic diagram of the relevant signals in the embodiment.

[0016] Explanation of icon numbers

[0017] 100, 400, 700: Display control circuit;

[0018] 110, 410, 710: Microcontroller units;

[0019] 120, 420, 720: storage units;

[0020] 130, 430, 730: Flash memory controller;

[0021] 140, 440, 740: Local dimming control registers;

[0022] 150, 450, 750: Control registers;

[0023] 201, 501: External control unit;

[0024] 202, 502, 702: Flash memory;

[0025] 503, 703: Ambient light sensor;

[0026] 504, 704: Deserializer;

[0027] DS1, DS2: Transmission status;

[0028] PU, DS3: Operating status;

[0029] S210~S230: Steps;

[0030] PS: Power supply status;

[0031] FSS: Frame Synchronization Signal;

[0032] LDC_SET0~LDC_SET4: LDC setting data;

[0033] C1~C4: Mode setting commands;

[0034] SV1, SV2: Mode settings;

[0035] t0~t10: Time;

[0036] AS: Ambient light sensor signal;

[0037] VS: Video signal;

[0038] EI: Error Indication. Detailed Implementation

[0039] Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same element references are used in the drawings and description to denote the same or similar parts.

[0040] Figure 1 This is a circuit diagram of a display control circuit according to an embodiment of the present disclosure. (Refer to...) Figure 1The display control circuit 100 includes a microcontroller unit (MCU) 110, a storage unit 120, a flash memory controller 130, a local dimming control (LDC) register 140, and a control register 150. The MCU 110 is coupled to the storage unit 120, the local dimming control register 140, and the control register 150. The storage unit 120 is also coupled to the flash memory controller 130. In this embodiment, the control register 150 is also coupled to an external control unit 201. The flash memory controller 130 is also coupled to a flash memory 202. In this embodiment, the local dimming control register 140 stores predefined LDC setting data applied synchronously with a frame synchronization signal. The display control circuit 100 provides relevant backlight control signals for local dimming operations based on the predefined LDC setting data stored in the local dimming control register 140 to drive the display panel to perform local dimming operations.

[0041] In one embodiment of this disclosure, the display control circuit 100, external control unit 201, and flash memory 202 can be integrated into an in-vehicle device, such as an in-vehicle infotainment (IVI) system. The display control circuit 100 is implemented in an integrated circuit (IC) capable of local dimming control of the backlight, such as a bridge IC, a timing controller (TCON) IC, or a timing controller-embedded display driver (TED), and can be used to drive the display panel and backlight of a dashboard or center information display (CID). The external control unit 201 is a device physically separate from the display control circuit 100, such as a system-on-chip (SOC), electronic control unit (ECU), or front-end microcontroller unit (MCU) of the IVI system. Furthermore, the display control circuit 100 may also include related display control circuitry, and is not limited to these. Figure 1 As shown in the image.

[0042] Figure 2 This is a flowchart of a display control method according to an embodiment of the present disclosure. (Refer to...) Figure 1 and Figure 2The display control circuit 100 can execute the following steps S210 to S230. In this embodiment, when the display control circuit 100 is powered on, the flash memory controller 130 can pre-read multiple predefined LDC setting data from the flash memory 202 and write the multiple predefined LDC setting data into the storage unit 120. In step S210, the control register 150 stores a first mode setting value. In this embodiment, the first mode setting value is carried in a mode setting command transmitted from the external control unit 201 to the display control circuit 100. In step S220, the microcontroller unit 110 reads the first predefined LDC setting data from the multiple predefined LDC setting data stored in the storage unit 120 according to the first mode setting value. In step S230, the microcontroller unit 110 writes the first predefined LDC setting data into the area dimming control register 140. In this embodiment, the microcontroller unit 110 can perform fast read and write operations on the area dimming control register 140 via the internal bus between the microcontroller unit 110 and the area dimming control register 140. Therefore, the microcontroller unit 110 can complete the reading and writing of the first predefined LDC setting data during the next frame period following the frame period in which the microcontroller unit 110 receives the mode setting command from the external control unit 201. That is, the display control circuit 100 can realize fast switching of area dimming settings.

[0043] Figure 3 Based on this disclosure Figure 1 A schematic diagram of the relevant signals in the embodiment. (Refer to...) Figure 1 and Figure 3 Where PS is a timing diagram describing the power supply state of the display control circuit 100; LDC setting is a timing diagram describing the LDC setting data stored in the area dimming control register 140; FSS is a timing diagram describing the frame synchronization signal; DS1 is a timing diagram describing the transmission from the external control unit 201 to the display control circuit 100; and DS2 is a timing diagram describing the transmission of the internal bus between the microcontroller unit 110 and the area dimming control register 140. (Refer to...) Figure 1 and Figure 3 The display control circuit 100 can be powered at time t0. During the period from time t0 to time t1, the flash memory controller 130 can pre-read multiple predefined LDC setting data (e.g., LDC_SET0 to LDC_SET3) from the flash memory 202 and write the multiple predefined LDC setting data into the storage unit 120. The multiple predefined LDC setting data (e.g., LDC_SET0 to LDC_SET3) are used to set multiple different LDC dimming modes for different areas.

[0044] Furthermore, before receiving a mode setting command for local dimming control, the microcontroller unit 110 pre-sets an initial local dimming control mode. This means that the microcontroller unit 110 reads one of a plurality of predefined LDC setting data, such as LDC_SET0, from the storage unit 120 and writes the read predefined LDC setting data LDC_SET0 into the local dimming control register 140 as the initial setting. The initial LDC setting data LDC_SET0 is synchronized with the frame synchronization signal FSS and applied for local dimming control.

[0045] Referring to transmission state DS1, at time t2, control register 150 can receive mode setting command C1 from external control unit 201. Mode setting command C1 includes mode setting value LDC_Mode, and microcontroller unit 110 uses mode setting value LDC_Mode equal to 2 as a reference to read the corresponding predefined LDC setting data LDC_SET2 from storage unit 120. Control register 150 can store mode setting value LDC_Mode=2.

[0046] Referring to transmission state DS2, at time t3, microcontroller unit 110 can read predefined LDC setting data LDC_SET2=2 from storage unit 120 according to the mode setting value, and write the predefined LDC setting data LDC_SET2 to the area dimming control register 140. It should be noted that microcontroller unit 110 can complete the reading and writing of the corresponding predefined LDC setting data LDC_SET2 within one frame period from time t3 to time t4, which immediately follows the frame period after microcontroller unit 110 receives the mode setting command C1. Therefore, at time t4, the LDC setting data of display control circuit 100 can be updated to the predefined LDC setting data LDC_SET2.

[0047] Furthermore, at time t5, the external control unit 201 can transmit a mode setting command C2 carrying the mode setting value LDC_Mode=4 and the corresponding custom LDC setting data LDC_SET4 to the display control circuit 100. The custom LDC setting data LDC_SET4 is not pre-stored in the storage unit 120. The control register 150 can store the received mode setting value (LDC_Mode=4) and the input custom LDC setting data (LDC_SET4).

[0048] At time t6, within one frame cycle (i.e., from time t6 to time t7), microcontroller unit 110 reads the custom LDC setting data LDC_SET4 input to display control circuit 100 from control register 150 according to the mode setting value LDC_Mode=4, and writes the custom LDC setting data LDC_SET4 into area dimming control register 140 via the internal bus between microcontroller unit 110 and area dimming control register 140. The frame cycle from time t6 to time t7 immediately follows the frame cycle after microcontroller unit 110 completes receiving the mode setting value and the input custom LDC setting data LDC_SET4. Therefore, at time t7, the LDC setting data of display control circuit 100 can be updated to the custom LDC setting data LDC_SET4.

[0049] Therefore, the microcontroller unit 110 can update the LDC setting data during a frame period immediately following the frame period in which the microcontroller unit 110 completes the reception mode setting command (with or without receiving custom LDC setting data) from the external control unit 201. The display control circuit 100 can enable rapid switching of local dimming settings without producing unpredictable transient display results.

[0050] Figure 4 This is a circuit diagram of a display control circuit according to an embodiment of the present disclosure. (Refer to...) Figure 4 The display control circuit 400 includes a microcontroller unit 410, a storage unit 420, a flash memory controller 430, a local dimming control register 440, a control register 450, and a protection unit 460. The microcontroller unit 410 is coupled to the storage unit 420, the local dimming control register 440, and the control register 450. The storage unit 420 is also coupled to the flash memory controller 430. The control register 450 is also coupled to the protection unit 460. In this embodiment, the control register 450 is also coupled to an external control unit 501. The flash memory controller 430 is coupled to a flash memory 502. The protection unit 460 is also coupled to an ambient light sensor 503 and a deserializer 504.

[0051] In this embodiment, the ambient light sensor 503 senses the brightness of ambient light (e.g., ambient light inside or outside the vehicle) and outputs an ambient light sensing signal AS to the protection unit 460. The ambient light sensing signal AS can be transmitted directly from the ambient light sensor 503 or via the automotive SoC to the display control circuit 400. The deserializer 504 provides a video signal VS to drive the display panel to display the corresponding video image. The deserializer 504 outputs the video signal VS to the protection unit 460. The image transmission path of the video signal VS can be from the automotive SoC via a serializer. Figure 4(Not shown in the image) and deserializer 504 to display control circuit 400, or directly from automotive SoC to display control circuit 400 without going through serializer and deserializer 504.

[0052] In this embodiment, the protection unit 460 is used to analyze at least one of the ambient light sensing signal AS and the video signal VS. Furthermore, the relevant circuit features and technical details of the display control circuit 400 can be found in [reference needed]. Figures 1 to 2 An example of this implementation. The display control circuit 400 can also perform... Figure 2 The display control method of the embodiment.

[0053] Figure 5 Based on this disclosure Figure 4 A schematic diagram of the relevant signals in the embodiment. (Refer to...) Figure 4 and Figure 5 In this diagram, PS is a timing diagram describing the power supply state of the display control circuit 400; LDC setting is a timing diagram describing the LDC setting data stored in the area dimming control register 440; AS is a timing diagram describing the ambient light sensing signal; FSS is a timing diagram describing the frame synchronization signal; DS1 is a timing diagram describing the transmission from the external control unit 501 to the display control circuit 400; PU is a timing diagram describing the operation of the protection unit 460; DS2 is a timing diagram describing the transmission of the internal bus between the microcontroller unit 410 and the area dimming control register 440; and EI is a timing diagram describing the error indication generated by the protection unit 460. In one embodiment of this disclosure, the display control circuit 400 can be started by being powered on at time t0. During the period from time t0 to time t1, the flash memory controller 430 can read multiple predefined LDC setting data (e.g., LDC_SET0 to LDC_SET3) from the flash memory 502 in advance and write the multiple predefined LDC setting data into the storage unit 420.

[0054] Furthermore, before receiving a mode setting command for local dimming control, the microcontroller unit 410 pre-sets an initial local dimming control mode. This means that the microcontroller unit 410 reads one of a plurality of predefined LDC setting data, such as LDC_SET0, from the storage unit 420 and writes the read predefined LDC setting data LDC_SET0 into the local dimming control register 440 as the initial setting. The initial LDC setting data LDC_SET0 is synchronized with the frame synchronization signal FSS and applied for local dimming control.

[0055] Referring to transmission state DS1, at time t2, when the ambient light brightness changes (e.g., when the vehicle enters a tunnel, the level of the ambient light sensor signal AS changes to below a first threshold), the external control unit 501 can output a mode setting command C3 containing a mode setting value LDC_Mode equal to 3. Due to unforeseen factors such as the external control unit 501 misinterpreting the ambient light sensor signal or electrostatic interference affecting signal transmission between the external control unit 501 and the display control circuit 400, the mode setting value (LDC_Mode=3) received by the display control circuit 400 may not match the mode setting value (e.g., LDC_Mode=2) expected to be applied to the area dimming control mode when the vehicle is traveling through a tunnel. The control register 450 can store the mode setting value.

[0056] Referring to the operating state PU, during the period from time t3 to time t4, the protection unit 460 can determine whether the mode setting value carried in the mode setting command C3 is reasonable based on the ambient light sensor signal AS. Figure 5 For example, if the protection unit 460 determines that the mode setting value (LDC_Mode=3) carried in the mode setting command C3 is unreasonable, and at time t4, the protection unit 460 generates an error indication EI with a logic high value corresponding to the determination result. This is because the received mode setting value (LDC_Mode=3) is different from the corresponding mode setting value expected for the area dimming control mode when the vehicle is passing through a tunnel, and the vehicle passing through a tunnel is indicated by the level of the ambient light sensor signal AS falling below a first threshold. Conversely, if the protection unit 460 determines that the mode setting value carried in the mode setting command is reasonable, the protection unit 460 generates an error indication EI with a logic low value corresponding to the determination result, indicating that the mode setting value is reasonable. The error indication EI can be a flag.

[0057] In other embodiments, during the period from time t3 to time t4, the protection unit 460 can determine whether the mode setting value carried in the mode setting command C3 is reasonable based on the image analysis results. For example, when the protection unit 460 determines that the area dimming control mode corresponding to the mode setting value (e.g., LDC_Mode=3) is used to enhance the brightness of a specific pattern in the input image frame, but by analyzing the input image frame in the video signal VS, the protection unit 460 identifies that there is no specific pattern in the input image frame that requires special illumination, the protection unit 460 can determine that the mode setting value carried in the mode setting command C3 is unreasonable. The protection unit 460 can determine whether the input image frame contains a specific pattern by distinguishing features such as histograms, frequency analysis, and grayscale statistics. Conversely, when the protection unit 460 determines that the area dimming control mode corresponding to the mode setting value (e.g., LDC_Mode=3) is used to enhance the brightness of a specific pattern in the input image frame, and the protection unit 460 identifies that there is a specific pattern in the input image frame that requires special illumination, the protection unit 460 can determine that the mode setting value carried in the mode setting command C3 is reasonable.

[0058] After the protection unit 460 generates an error indication EI corresponding to the judgment result that the presentation mode setting value is unreasonable, during the period from time t5 to time t6, even if the judgment result that the presentation mode setting value (LDC_Mode=3) is unreasonable, the microcontroller unit 410 still reads the predefined LDC setting data LDC_SET3 from the storage unit 420 according to the mode setting value (LDC_Mode=3) and writes the predefined LDC setting data LDC_SET3 into the area dimming control register 440. Therefore, at time t6, the LDC setting data of the display control circuit 400 can be updated to the predefined LDC setting data LDC_SET3.

[0059] Optionally, in other embodiments of this disclosure, the microcontroller unit 410 may only read the predefined LDC setting data LDC_SET3 from the storage unit 420 and write the predefined LDC setting data LDC_SET3 into the area dimming control register 440 when the error indication EI generated by the protection unit 460 indicates that the judgment result display mode setting value is reasonable.

[0060] Referring again to transmission state DS1, at time t7, when the ambient light brightness changes again (for example, the level of the ambient light sensor signal AS changes to be higher than the second threshold), the external control unit 501 can output a mode setting command C4 with a mode setting value LDC_Mode equal to 0. The mode setting value LDC_Mode=0 can be used to request setting the LDC mode according to the predefined LDC setting data LDC_SET0. The control register 450 can store the mode setting value LDC_Mode=0.

[0061] During the period from time t8 to time t9, the protection unit 460 can determine whether the mode setting value carried in the mode setting command C4 is reasonable based on the ambient light sensor signal AS or the image analysis results.

[0062] like Figure 5 As shown, the protection unit 460 determines that the mode setting value (LDC_Mode=0) carried in the mode setting command C4 is reasonable. Therefore, at time t9, the protection unit changes the error indicator EI to a logic low value, which corresponds to the judgment result that the mode setting value is reasonable. The error indicator EI can be used to notify the front end that the abnormal situation has been resolved.

[0063] At time t9, as shown in transmission state DS2, the microcontroller unit 410 reads the predefined LDC setting data LDC_SET0 from the storage unit 420 according to the mode setting value, and writes the predefined LDC setting data LDC_SET0 to the area dimming control register 440 via the internal bus. Therefore, at time t10, after the microcontroller unit 410 completes the reading and writing of the predefined LDC setting data LDC_SET0, the LDC setting data of the display control circuit 400 can be updated to the predefined LDC setting data LDC_SET0.

[0064] Therefore, the display control circuit 400 can enable rapid switching of local dimming settings without producing unpredictable transient display results, and can notify the front-end system of abnormal situations in a timely manner via error indication EI.

[0065] Figure 6 Based on this disclosure Figure 4 Another schematic diagram of the relevant signals in the embodiment. (Refer to...) Figure 4 and Figure 6 In another embodiment of this disclosure, with Figure 5 In a different embodiment, after the protection unit 460 generates an error indication EI corresponding to a judgment result that the presentation mode setting value is unreasonable, the microcontroller unit 410 does not read the predefined LDC setting data LDC_SET3 from the storage unit 420 according to the mode setting value, nor does it write the predefined LDC setting data LDC_SET3 corresponding to the mode setting value into the area dimming control register 440. Therefore, with Figure 6 For example, at time t5, the LDC setting data of the display control circuit 400 can remain unchanged from the previous data, still being the predefined LDC setting data LDC_SET0.

[0066] At time t6, when the ambient light intensity changes again (for example, the level of the ambient light sensor signal AS changes to be higher than the second threshold), the external control unit 501 can output a mode setting command C4 containing a mode setting value LDC_Mode equal to 0. The control register 450 can store the mode setting value LDC_Mode=0.

[0067] During the period from time t7 to time 8, the protection unit 460 can determine whether the mode setting carried in the mode setting command C4 is reasonable based on the ambient light sensor signal AS or image analysis results. For example... Figure 6 As shown, the protection unit 460 determines that the mode setting value (LDC_Mode=0) carried in the mode setting command C4 is reasonable. Therefore, at time t8, the protection unit 460 changes the error indication EI to a logic low value, which corresponds to the judgment result that the mode setting value is reasonable.

[0068] At time t8, such as Figure 6 In the transmission state DS2, the microcontroller unit 410 reads the predefined LDC setting data LDC_SET0 from the storage unit 420 according to the mode setting value (LDC_Mode=0), and writes the predefined LDC setting data LDC_SET0 to the area dimming control register 440. Therefore, at time t9, that is, in the next frame cycle after the microcontroller unit 410 completes the reading and writing of the predefined LDC setting data LDC_SET0, the LDC setting data of the display control circuit 400 can be updated to the predefined LDC setting data LDC_SET0.

[0069] Therefore, the display control circuit 400 can enable the maintenance of local dimming settings under scene changes without producing unpredictable transient display results, and can promptly notify the front-end system of abnormal conditions via error indication EI.

[0070] Figure 7 This is a circuit diagram of a display control circuit according to an embodiment of the present disclosure. (Refer to...) Figure 7 The display control circuit 700 includes a microcontroller unit 710, a storage unit 720, a flash memory controller 730, a local dimming control register 740, a control register 750, and a decision unit 770. The microcontroller unit 710 is coupled to the storage unit 720, the local dimming control register 740, and the control register 750. The storage unit 720 is also coupled to the flash memory controller 730. The control register 750 is also coupled to the decision unit 770. The flash memory controller 730 is coupled to a flash memory 702. The decision unit 770 is also coupled to an ambient light sensor 703 and a deserializer 704. In one embodiment of this disclosure, the decision unit 770 may be integrated into the microcontroller unit 710, or may be implemented as other circuitry within the display control circuit 700.

[0071] In embodiments of this disclosure, an ambient light sensor 703 senses the brightness of ambient light (e.g., ambient light inside or outside the vehicle) and outputs an ambient light sensing signal AS to a determination unit 770. A deserializer 704 provides a video signal VS to drive the display panel to display a corresponding video image. The deserializer 704 outputs the video signal VS to the determination unit 770. In embodiments of this disclosure, the determination unit 770 identifies and switches the LDC mode based on at least one of the ambient light sensing signal AS and the video signal VS, and generates a mode setting value based on the identification result. That is, the display control circuit 700 can generate the mode setting value itself. Furthermore, the relevant circuit features and technical details of the display control circuit 700 can be found in [reference needed]. Figures 1 to 2 An embodiment. The display control circuit 700 can also perform... Figure 2 The display control method of this embodiment. Different from... Figure 1 The display control circuit 100 and Figure 4 The display control circuit 400 determines which area dimming control mode should be used based on information transmitted from the external control unit. The display control circuit 700 does not refer to the mode setting value transmitted from the external control unit when determining the area dimming mode.

[0072] Figure 8 Based on this disclosure Figure 7 A schematic diagram of the relevant signals in an embodiment. (Refer to...) Figure 7 and Figure 8 In this diagram, PS is a timing diagram describing the power supply status of the display control circuit 700; LDC setting is a timing diagram describing the LDC setting data stored in the local dimming control register 740; AS is a timing diagram describing the ambient light sensing signal; FSS is a timing diagram describing the frame synchronization signal; DS2 is a timing diagram describing the transmission of the internal bus between the microcontroller unit 710 and the local dimming control register 740; and DS3 is a timing diagram describing the operation of the judgment unit 770. The display control circuit 700 can be powered on at time t0. During the period from time t0 to time t1, the flash memory control 730 can pre-read multiple predefined LDC setting data (e.g., LDC_SET0 to LDC_SET3) from the flash memory 702 and write the multiple predefined LDC setting data into the storage unit 720. Before receiving a mode setting command for local dimming control, the microcontroller unit 710 pre-sets an initial local dimming control mode, the setting method being the same as... Figure 3 and Figure 5 The initial area dimming control mode setting process described in the previous section is the same, so it will not be repeated here.

[0073] Referring to the operating state DS3, at time t2, when the brightness of the ambient light changes (for example, the level of the ambient light sensing signal AS changes to be lower than the first threshold), the determination unit 770 can determine the LDC mode based on the ambient light sensing signal AS or the image analysis result (generated based on the video signal VS), and the determination unit 770 can output the corresponding mode setting value SV1 (for example, for setting LDC_Mode=2) to the control register 750.

[0074] For example, the determination unit 770 can determine that the scene is a low-light environment (e.g., a vehicle driving inside a tunnel) based on the ambient light sensor signal AS. Therefore, the determination unit 770 can output the mode setting value SV1 corresponding to LDC mode 2 to the control register 750. Thus, the microcontroller unit 710 can write the predefined LDC setting data LDC_SET2 into the area dimming control register 740. The area dimming mode set according to the mode setting value SV1 (corresponding to LDC mode 2) can adjust the grayscale of the warning icon in the input image frame displayed on the display panel to a high-brightness display effect.

[0075] At time t3, the microcontroller unit 710 reads the predefined LDC setting data LDC_SET2 from the storage unit 720 according to the mode setting value SV1, and writes the predefined LDC setting data LDC_SET2 into the area dimming control register 740 via the internal bus. Therefore, at time t4, the LDC setting data of the display control circuit 700 can be updated to the predefined LDC setting data LDC_SET2.

[0076] At time t5, when the ambient light brightness changes again (for example, the level of the ambient light sensor signal AS changes to be higher than the second threshold), the determination unit 770 can determine the LDC mode based on the ambient light sensor signal AS or the image analysis result (generated based on the video signal VS), and the determination unit 770 can output the mode setting value SV2 corresponding to another LDC mode 0 to the control register 750. The control register 750 can store the mode setting value SV2.

[0077] At time t6, the microcontroller unit 710 can read the predefined LDC setting data LDC_SET0 from the storage unit 720 according to the mode setting value SV2, and write the predefined LDC setting data LDC_SET0 to the area dimming control register 740. Therefore, at time t7, the LDC setting data of the display control circuit 700 can be updated to the predefined LDC setting data LDC_SET0.

[0078] For example, the determination unit 770 can determine that the scene has returned to a normal brightness environment based on the ambient light sensor signal AS. Therefore, the determination unit 770 can output the mode setting value SV2 to the control register 750. As a result, the microcontroller unit 710 can write the predefined LDC setting data LDC_SET2 into the area dimming control register 740, thereby restoring the original area dimming effect.

[0079] Therefore, the display control circuit 700 can enable rapid switching of local dimming settings without producing unpredictable transient display results.

[0080] The aforementioned display control circuits 100, 400, and 700 can be implemented in an integrated circuit (IC) capable of local dimming control of the backlight, such as an image bridge IC, a timing controller (TCON) IC, or a timing controller embedded display driver (TED) IC, and can be used to drive the display panel and backlight of the instrument panel or center information display (CID) in a vehicle.

[0081] In summary, the display control circuit and method disclosed herein can achieve rapid scene mode switching and can be combined with ambient light sensing or image sensing to achieve adaptive local dimming. The disclosed display control circuit and method can also automatically determine whether mode switching is reasonable and generate corresponding notifications to the front end.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A display control circuit, characterized in that, include: Storage unit, used to store multiple predefined LDC setting data; A control register is used to store the first mode setting value; The local dimming control register is used to store LDC setting data that is applied synchronously with the frame synchronization signal; as well as A microcontroller unit is coupled to the control register and the area dimming control register, and is used to read the first predefined LDC setting data of the plurality of predefined LDC setting data stored in the storage unit according to the first mode setting value, and write the first predefined LDC setting data into the area dimming control register.

2. The display control circuit according to claim 1, characterized in that, The first mode setting value is carried in a mode setting command transmitted from an external control unit.

3. The display control circuit according to claim 2, characterized in that, The microcontroller unit completes reading and writing the first predefined LDC setting data during the next frame period after receiving the mode setting command.

4. The display control circuit according to claim 1, characterized in that, The control register is also used to store input LDC setting data transmitted from the external control unit, and the microcontroller unit is also used to read the input LDC setting data from the control register and write the input LDC setting data into the area dimming control register.

5. The display control circuit according to claim 4, characterized in that, The microcontroller unit completes reading and writing the input LDC setting data during the next frame period after completing the frame period of receiving the input LDC setting data.

6. The display control circuit according to claim 2, characterized in that, Also includes: The protection unit is coupled to the control register and is used to determine whether the first mode setting value carried in the mode setting command is reasonable, and to generate an error indication corresponding to the judgment result that the first mode setting value is reasonable or unreasonable.

7. The display control circuit according to claim 6, characterized in that, The protection unit determines whether the setting value of the first mode is reasonable based on the ambient light sensor signal.

8. The display control circuit according to claim 6, characterized in that, The protection unit determines whether the mode setting value is reasonable based on the image analysis results.

9. The display control circuit according to claim 6, characterized in that, After the protection unit generates the error indication corresponding to the judgment result that the first mode setting value is unreasonable, even if the judgment result indicates that the first mode setting value is unreasonable, the microcontroller unit still reads the first predefined LDC setting data from the storage unit and writes the first predefined LDC setting data into the area dimming control register.

10. The display control circuit according to claim 6, characterized in that, The microcontroller unit reads the first predefined LDC setting data from the storage unit and writes the first predefined LDC setting data into the area dimming control register only when the protection unit generates the error indication corresponding to the judgment result that presents the first mode setting value reasonably.

11. The display control circuit according to claim 6, characterized in that, After the control register is overwritten by the second mode setting value carried in the mode setting command, and the protection unit generates another error indication corresponding to the judgment result that the second mode setting value is unreasonable, the microcontroller unit does not write the second predefined LDC setting data corresponding to the second mode setting value into the area dimming control register.

12. The display control circuit according to claim 1, characterized in that, The first mode setting value is generated by the display control circuit.

13. The display control circuit according to claim 12, characterized in that, Also includes: The determination unit is used to determine the LDC mode based on the ambient light sensor signal or video signal and output the first mode setting value corresponding to the LDC mode to the control register.

14. A display control method, characterized in that, include: The first mode setting value is stored in the control register; The microcontroller unit reads the first predefined LDC setting data from a plurality of predefined LDC setting data stored in the storage unit according to the first mode setting value; as well as The microcontroller unit writes the first predefined LDC setting data into the area dimming control register. The area dimming control register is used to store predefined LDC setting data that is applied synchronously with the frame synchronization signal.

15. The display control method according to claim 14, characterized in that, The first mode setting value is carried in a mode setting command transmitted from an external control unit.

16. The display control method according to claim 15, characterized in that, The microcontroller unit completes reading and writing the first predefined LDC setting data during the next frame period after the frame period in which the microcontroller unit receives the mode setting command.

17. The display control method according to claim 14, characterized in that, Also includes: The control register stores the input LDC setting data transmitted from the external control unit; as well as The microcontroller unit reads the input LDC setting data from the control register and writes the input LDC setting data into the area dimming control register.

18. The display control method according to claim 17, characterized in that, The microcontroller unit completes reading and writing the input LDC setting data in the next frame period after the microcontroller unit completes receiving the input LDC setting data.

19. The display control method according to claim 15, characterized in that, Also includes: The protection unit determines whether the first mode setting value carried in the mode setting command is reasonable. as well as The protection unit generates an error indication corresponding to the judgment result, which indicates whether the first mode setting value is reasonable or unreasonable.

20. The display control method according to claim 19, characterized in that, Also includes: The protection unit determines whether the setting value of the first mode is reasonable based on the ambient light sensor signal.

21. The display control method according to claim 19, characterized in that, Also includes: The protection unit determines whether the mode setting value is reasonable based on the image analysis results.

22. The display control method according to claim 19, characterized in that, Also includes: After the protection unit generates the error indication corresponding to the judgment result that the first mode setting value is unreasonable, the microcontroller unit reads the first predefined LDC setting data from the storage unit and writes the first predefined LDC setting data into the area dimming control register, even if the judgment result shows that the first mode setting value is unreasonable.

23. The display control method according to claim 19, characterized in that, Also includes: The microcontroller unit reads the first predefined LDC setting data from the storage unit; as well as Only when the protection unit generates the error indication corresponding to the judgment result that presents the first mode setting value reasonably, the microcontroller unit writes the first predefined LDC setting data into the area dimming control register.

24. The display control method according to claim 19, characterized in that, Also includes: After the control register is overwritten by the second mode setting value carried in the mode setting command and the protection unit generates another error indication corresponding to the judgment result that the second mode setting value is unreasonable, the microcontroller unit does not write the second predefined LDC setting data corresponding to the second mode setting value into the area dimming control register.

25. The display control method according to claim 14, characterized in that, Also includes: The first mode setting value is generated by the display control circuit.

26. The display control method according to claim 25, characterized in that, Also includes: The judgment unit determines the LDC mode based on ambient light sensor signals or video signals. as well as The judgment unit outputs the first mode setting value corresponding to the LDC mode to the control register.

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