Controller, light source control system, and display system

Abstract

To provide a controller or the like capable of detecting an error in the entire processing path of the controller and a light source driver.SOLUTION: The controller 100 includes the control-data generation circuit 110, the first interface circuit 140, the first storage circuit 120, and the error detection circuit 130. The control-data generation circuit 110 generates the control-data CTD based on the brightness-data LMD, the first interface circuit 120 transmits the control-data CTD, and the first storage circuit 130 stores the first comparison-data CP1 based on the brightness-data LMD or the control-data CTD. The light source driver 200 includes a second interface circuit 240 that receives the control data CTD, a second storage circuit 230 that stores the control data CTD, and a drive circuit 250 that drives the light source 300 based on the control data CTD. The error detection circuit 130 compares the first comparison signal CP1 with the second comparison signal based on the control signal CTD _ RB received by the first interface circuit 140 from the second interface circuit 240.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a controller, a light source control system, a display system, and the like. [Background technology]

[0002] Patent Document 1 discloses a lamp controller for controlling vehicle headlamps. The lamp controller includes a rendering processing unit that generates multi-level light distribution image data that defines the light distribution of a variable light distribution lamp, and a device interface circuit that transmits the light distribution image data to a patterning device. The patterning device includes an interface circuit that receives the light distribution image data and an LED array that emits light based on the light distribution image data. The lamp controller includes a monitoring microcomputer, which performs self-diagnosis for abnormalities for each software process. The rendering processing unit, device interface circuit, and patterning device are equipped with self-diagnosis functions and transmit data indicating the diagnosis results to the monitoring microcomputer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2022 / 270414 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, diagnosis can only be performed for each software process, and therefore error checks can only be performed individually for processes within the lamp controller or the patterning device. [Means for solving the problem]

[0005] One aspect of the present disclosure relates to a controller that transmits control data to a light source driver that drives a light source based on control data that controls the brightness of the light source, the controller including: a control data generation circuit that generates the control data based on brightness data indicating the brightness; a first interface circuit that transmits the control data to the light source driver; a first memory circuit that stores first comparison data based on the brightness data or the control data; and an error detection circuit that performs error detection using the stored first comparison data; the light source driver includes a second interface circuit that receives the control data, a second memory circuit that stores the received control data, and a drive circuit that drives the light source based on the stored control data; the first interface circuit receives the control data stored in the second memory circuit from the second interface circuit; and the error detection circuit performs error detection in the control data received from the light source driver by comparing the first comparison data with second comparison data based on the control data received from the light source driver.

[0006] Another aspect of the present disclosure relates to a light source control system including the above controller and the light source driver.

[0007] Furthermore, still another aspect of the present disclosure relates to a display system including the above-described controller, the light source driver, the light source, and a display panel onto which light from the light source is incident. [Brief explanation of the drawings]

[0008] [Figure 1] 1 shows a first example of a light source control system configuration. [Figure 2] 2 shows a second example of a light source control system configuration. [Figure 3] First detailed configuration example of the controller. [Figure 4] Second detailed configuration example of the controller. [Figure 5] Third detailed configuration example of the controller. [Figure 6]4th detailed configuration example of the controller. [Figure 7] A detailed example of the configuration of a light control system when a controller controls multiple light source drivers. [Figure 8] 10 shows an example of the controller's processing flow when multiple light source drivers are installed. [Figure 9] 10 shows an example of the controller's processing flow when multiple light source drivers are installed. [Figure 10] 10 shows an example of the controller's processing flow when multiple light source drivers are installed. [Figure 11] The first detailed configuration example of the controller when performing a sticking check. [Figure 12] A second detailed configuration example of the controller when performing a sticking check. [Figure 13] 10 is a configuration example of a controller for explaining the operation of the controller 100 when an error is detected. [Figure 14] 10 shows an example of the configuration of an electronic device when a controller performs local dimming processing. [Figure 15] A detailed example of the controller configuration when performing local dimming processing. DETAILED DESCRIPTION OF THE INVENTION

[0009] Preferred embodiments of the present disclosure will be described in detail below. Note that the embodiments described below do not unduly limit the scope of the claims, and not all of the configurations described in the embodiments are necessarily essential components.

[0010] 1.Configuration example 1 shows a first example configuration of a light source control system 10. The light source control system 10 is a system that controls a light source 300, for example, by controlling the on / off and light emission brightness of the light source 300. The light source control system 10 includes a controller 100 and a light source driver 200.

[0011] The light source 300 is a light-emitting element that converts electrical energy into light. The light-emitting element is, for example, an inorganic or organic LED. LED stands for Light Emitting Diode. While FIG. 1 shows an example in which the light source driver 200 drives one light source 300, the light source driver 200 may drive multiple light sources 300.

[0012] The controller 100 converts luminance data LMD indicating the luminance of the light source 300 into control data CTD for controlling the light source driver 200, and transmits the control data CTD to the light source driver 200. The controller 100 includes a control data generation circuit 110, a first storage circuit 120, an error detection circuit 130, and a first interface circuit 140. The controller 100 is, for example, an integrated circuit device in which a plurality of circuit elements are integrated on a semiconductor substrate.

[0013] The light source driver 200 drives the light source 300 based on the control data CTD received from the controller 100. The light source driver 200 includes a second interface circuit 240, a second memory circuit 230, and a driving circuit 250. The light source driver 200 is, for example, an integrated circuit device in which a plurality of circuit elements are integrated on a semiconductor substrate.

[0014] First, the operation of each component involved in driving the light source 300 will be described. The control data generation circuit 110 converts the luminance data LMD into control data CTD. The luminance data LMD is, for example, data that represents luminance using gradation values ​​of a given number of gradations. The luminance data LMD may be generated, for example, by a dimming processing circuit (not shown) built into the controller 100, or may be generated by a host device or the like and input from outside the controller 100. The control data CTD is data used by the light source driver 200 to control the light source 300, and is, for example, PWM data or current value data, the details of which will be described later. PWM stands for Pulse Width Modulation.

[0015] The first interface circuit 140 transmits the control data CTD to the second interface circuit 240. The second interface circuit 240 receives the control data CTD from the first interface circuit 140. Various inter-IC interface standards may be used as the interface standards of the first interface circuit 140 and the second interface circuit 240. As an example, a serial interface standard such as SPI or I2C may be adopted. SPI stands for Serial Peripheral Interface. I2C stands for Inter-Integrated Circuit. Alternatively, a shift register method may be adopted in which the transmitting side transmits serial data and a latch pulse, and the receiving side inputs the serial data into a shift register and determines the data by the latch pulse.

[0016] The second storage circuit 230 stores the control data CTD received by the second interface circuit 240. The second storage circuit 230 is, for example, a register such as a latch circuit, or a semiconductor memory such as an SRAM or a DRAM.

[0017] The drive circuit 250 drives the light source 300 based on the control data CTD stored in the second storage circuit 230. When the drive circuit 250 drives a plurality of light sources 300, the control data CTD may be specified for each individual light source 300, or the control data CTD may be specified for each unit including two or more light sources 300, or one control data CTD may be specified for all of the plurality of light sources 300. As examples of the control data CTD, PWM data and current value data will be described.

[0018] The PWM data is data for PWM control of the light source 300, and is data that specifies, for example, an on-duty or an on-duty corresponding to brightness. In this case, the light source 300 and a switch are connected in series between a power supply node and a ground node. The drive circuit 250 drives the light source 300 by controlling the switch to turn on or off using a pulse signal based on the PWM data. It can be said that the on-duty or the on-duty of the PWM data indicates the pulse width of the pulse signal.

[0019] The current value data is data for controlling the value of the current flowing through the light source 300, and is data that specifies a current value according to brightness. In this case, a sense resistor, the light source 300, an inductor, and a switch are connected in series between a power supply node and a ground node. The drive circuit 250 controls the value of the current flowing through the light source 300 by feedback control. Specifically, the drive circuit 250 detects the value of the current flowing through the light source 300 using the potential difference between both ends of the sense resistor, and controls the switching of the switch so that the current value becomes the current value indicated by the current value data.

[0020] Next, the operation of each unit related to error detection will be described. The first memory circuit 120 stores first comparison data CP1 based on the control data CTD. The first comparison data CP1 is an error check code generated from the control data CTD by the error detection circuit 130, or the control data CTD itself. The first memory circuit 120 is, for example, a register such as a latch circuit, or a semiconductor memory such as an SRAM or DRAM.

[0021] The second interface circuit 240 reads out the control data CTD from the second memory circuit 230 and transmits it to the first interface circuit 140. This read out control data is referred to as CTD_RB. The first interface circuit 140 receives the control data CTD_RB from the second interface circuit 240. As an example, the first interface circuit 140 issues a read command, and the second interface circuit 240 reads out the control data CTD_RB from the second memory circuit 230 in response to the read command and transmits it to the first interface circuit 140.

[0022] The error detection circuit 130 compares second comparison data based on the control data CTD_RB with the first comparison data CP1 stored in the first storage circuit 120. The second comparison data is the same type of data as the first comparison data CP1, and is either an error check code generated by the error detection circuit 130 from the control data CTD_RB or the control data CTD_RB itself. The error detection circuit 130 determines that there is no error if the first comparison data CP1 and the second comparison data match, and determines that there is an error if the first comparison data CP1 and the second comparison data do not match. The error detection circuit 130 outputs the result of the error detection as an error signal ERR. The error signal ERR is also called an error flag.

[0023] Fig. 2 shows a second configuration example of the light source control system 10. The operation of each unit related to driving the light source 300 is the same as in Fig. 1. Regarding the operation of each unit related to error detection, differences from Fig. 1 will be described.

[0024] The first storage circuit 120 stores first comparison data CP1 based on the luminance data LMD. The first comparison data CP1 is an error check code generated from the luminance data LMD by the error detection circuit 130, or the luminance data LMD itself.

[0025] The error detection circuit 130 compares the second comparison data based on the control data CTD_RB with the first comparison data CP1 stored in the first storage circuit 120. The second comparison data is the same type of data as the first comparison data CP1, and is either an error check code generated from the luminance data after the error detection circuit 130 converts the control data CTD_RB into luminance data, or the luminance data itself.

[0026] In this embodiment, the controller 100 transmits control data CTD to the light source driver 200, which drives the light source 300 based on the control data CTD to control the brightness of the light source 300. The controller 100 includes a control data generation circuit 110 that generates the control data CTD based on brightness data LMD indicating brightness, and a first interface circuit 140 that transmits the control data CTD to the light source driver 200. The controller 100 also includes a first memory circuit 120 that stores first comparison data CP1 based on the brightness data LMD or the control data CTD, and an error detection circuit 130 that performs error detection using the stored first comparison data CP1. The light source driver 200 includes a second interface circuit 240 that receives the control data CTD, a second memory circuit 230 that stores the received control data CTD, and a drive circuit 250 that drives the light source 300 based on the stored control data CTD. The first interface circuit 140 receives the control data CTD stored in the second memory circuit 230 from the second interface circuit 240. The error detection circuit 130 performs error detection on the control data CTD_RB received from the light source driver 200 by comparing the first comparison data CP1 with second comparison data based on the control data CTD_RB received from the light source driver 200.

[0027] According to this embodiment, rather than detecting errors in the controller 100 alone or the light source driver 200 alone, error detection for the entire processing path of the controller 100 and the light source driver 200 can be executed in the controller 100. For example, operational abnormalities in the control data generation circuit 110, the first interface circuit 140, the second interface circuit 240, and the second memory circuit 230, or disconnections within or between the circuits, or communication abnormalities between the circuits can be detected as errors.

[0028] Furthermore, when data transmitted from the controller 100 is to be error checked within the light source driver 200, the controller 100 must calculate an expected value in accordance with an arithmetic expression for the error check code within the light source driver 200 and transmit the calculated value to the light source driver 200. According to this embodiment, by reading the control data CTD from the light source driver 200 and performing error detection within the controller 100, it is not necessary to consider the arithmetic expression for the error check code within the light source driver 200. This allows for flexible adoption of error detection specifications.

[0029] Furthermore, while the error detection in this embodiment may be performed using either software or hardware processing, hardware processing allows for simpler design and faster processing compared to software processing. Here, software processing refers to processing that implements a function through a program using a general-purpose microcomputer or the like. Here, hardware processing refers to processing that implements a function using hardware specifically designed to implement the function through its own circuit configuration. Software processing requires rewriting the program according to the specifications of the adopted light source driver 200. On the other hand, hardware processing requires fewer design changes, such as rewriting the program, by simply adjusting the interface standard of the first interface circuit 140 to the specifications of the light source driver 200 through register settings, for example. Furthermore, when comparing hardware and software processing that implement the same function, hardware processing is typically faster. Using hardware processing enables high-speed error detection, enabling error detection, for example, on a frame-by-frame basis.

[0030] In this embodiment, the first comparison data CP1 and the second comparison data may be an error check code generated from the control data CTD, an error check code generated from the luminance data LMD, the control data CTD, or the luminance data LMD.

[0031] According to this embodiment, the error detection specifications can be freely adopted, and therefore, errors can be detected using the various error check codes and data described above according to the type of error detection desired. Various error check code standards can also be selected, such as CRC, checksum, or parity check.

[0032] In this embodiment, the control data CTD may be PWM data indicating the pulse width of a pulse signal that drives the light source 300, or current value data indicating the current value that drives the light source 300.

[0033] According to this embodiment, the controller 100 can detect whether the PWM data or current value data stored in the second memory circuit 230 of the light source driver 200 matches the PWM data or current value data transmitted by the controller 100. This makes it possible to check whether the light source 300 is being driven by the correct PWM data or current value data.

[0034] 2. Detailed configuration example 3 shows a first detailed configuration example of the controller 100. In this configuration example, the error detection circuit 130 includes a first error check code generation circuit 131, a second error check code generation circuit 132, and a comparison circuit 135.

[0035] The first error check code generation circuit 131 converts the control data CTD into an error check code and stores the error check code as first comparison data CP1 in the first storage circuit 120. The error check code may be a code used in various error check methods, such as CRC, checksum, or parity code. CRC stands for Cyclic Redundancy Check. The first error check code generation circuit 131 may convert each piece of control data CTD corresponding to one light source into first comparison data CP1, or may convert control data CTD corresponding to multiple light sources together into one piece of first comparison data CP1.

[0036] The second error check code generation circuit 132 converts the control data CTD_RB into an error check code and outputs the error check code as second comparison data CP2 to the comparison circuit 135. The second error check code generation circuit 132 generates the second comparison data CP2 using the same algorithm as the conversion algorithm used by the first error check code generation circuit 131.

[0037] The comparator circuit 135 compares the first comparison data CP1 stored in the first storage circuit 120 with the second comparison data CP2 from the second error check code generator circuit 132, and outputs the result as an error signal ERR.

[0038] The light emission luminance of light source 300 is updated, for example, for each frame. At this time, error detection circuit 130 performs error detection for each frame. That is, error detection circuit 130 generates first comparison data CP1 and second comparison data CP2 corresponding to control data CTD for each frame and compares them. Note that the frame here may be a frame in light source control, or may be a display frame when the light source is used as a backlight for a display device.

[0039] 4 shows a second detailed configuration example of the controller 100. In this configuration example, the error detection circuit 130 includes a first error check code generation circuit 131, a second error check code generation circuit 132, a comparison circuit 135, and a conversion circuit 136. The following describes the differences from FIG. 3.

[0040] The first error check code generation circuit 131 converts the luminance data LMD into an error check code, and stores the error check code in the first storage circuit 120 as first comparison data CP1.

[0041] The conversion circuit 136 converts the control data CTD_RB into luminance data LMD_RB. The conversion circuit 136 generates the luminance data LMD_RB by performing an inverse conversion of the conversion performed by the control data generation circuit 110. For example, when the control data generation circuit 110 performs a conversion that uniquely associates the luminance data LMD with the control data CTD, the conversion circuit 136 can inversely convert the control data CTD_RB into luminance data LMD_RB.

[0042] The second error check code generation circuit 132 converts the luminance data LMD_RB into an error check code, and outputs the error check code to the comparison circuit 135 as second comparison data CP2.

[0043] 5 shows a third detailed configuration example of the controller 100. In this configuration example, the error detection circuit 130 includes a comparison circuit 135. Below, differences from FIGS. 3 and 4 will be described.

[0044] The comparison circuit 135 receives the control data CTD stored in the first storage circuit 120 as first comparison data CP1, and receives the control data CTD_RB received by the first interface circuit 140 as second comparison data CP2. The comparison circuit 135 compares the input first comparison data CP1 and second comparison data CP2, and outputs the result as an error signal ERR.

[0045] 6 shows a fourth detailed configuration example of the controller 100. In this configuration example, the error detection circuit 130 includes a comparison circuit 135 and a conversion circuit 136. Below, the parts that differ from FIGS. 3 to 5 will be described.

[0046] The comparison circuit 135 receives the luminance data LMD stored in the first storage circuit 120 as first comparison data CP1, and receives the luminance data LMD_RB from the conversion circuit 136 as second comparison data CP2. The comparison circuit 135 compares the input first comparison data CP1 and second comparison data CP2, and outputs the result as an error signal ERR.

[0047] Fig. 7 shows a detailed configuration example of the light source control system 10 when the controller 100 controls multiple light source drivers. The light source control system 10 includes the controller 100 and a first light source driver 200-1 to an n-th light source driver 200-n, where n is an integer equal to or greater than 2. In Fig. 7, the control data generation circuit, first memory circuit, and error detection circuit of the controller 100, and the second memory circuit of each light source driver are not shown.

[0048] The second interface circuit 240-1 of the first light source driver 200-1, the second interface circuit 240-2 of the second light source driver 200-2, ..., the second interface circuit 240-n of the n-th light source driver 200-n are connected in series by a daisy chain to the first interface circuit 140 of the controller 100. The daisy chain is a communication connection that transfers data sequentially from the first light source driver 200-1 to the n-th light source driver 200-n according to an interface standard such as SPI.

[0049] The connection between the controller 100 and each light source driver is not limited to a daisy chain. For example, the second interface circuits 240-1 to 240-n may be communicatively connected in parallel to one communication port of the first interface circuit 140. Alternatively, the first interface circuit 140 may have n communication ports, and the second interface circuits of one light source driver may be communicatively connected to each communication port.

[0050] The driving circuit 250-1 of the first light source driver 200-1 drives the light source 300-1 based on the control data received by the second interface circuit 240-1. Similarly, the driving circuit 250-2 of the second light source driver 200-2 drives the light source 300-2 based on the control data received by the second interface circuit 240-2, and so on, and the driving circuit 250-n of the n-th light source driver 200-n drives the light source 300-n based on the control data received by the second interface circuit 240-n.

[0051] 8 to 10 show an example of a processing flow of the controller 100 when multiple light source drivers are provided as in Fig. 7. Here, an example is shown in which the control data CTD is PWM data, and the first comparison data CP1 and second comparison data CP2 are CRC values.

[0052] In step S1, luminance data LMD is input to the control data generation circuit 110. In step S2, the control data generation circuit 110 converts the luminance data LMD into PWM data. In step S3, the first error check code generation circuit 131 calculates a CRC expected value from the PWM data and stores the CRC expected value in the first storage circuit 120. In step S4, the first interface circuit 140 transmits and receives PWM data to and from the first light source driver 200-1 to the n-th light source driver 200-n. Details of S4 will be described with reference to FIGS. 9 and 10. Note that S3 and S4 may be executed in parallel.

[0053] In step S5, the second error check code generation circuit 132 calculates a CRC value from the PWM data received in step S4. In step S6, the comparison circuit 135 determines whether the CRC expected value stored in the first storage circuit 120 in step S3 matches the CRC value calculated in step S5. If it is determined in step S6 that the CRC expected value and the CRC value match, the controller 100 waits for processing of the next frame in step S7, and executes from S1 after starting processing of the next frame. If it is determined in step S6 that the CRC expected value and the CRC value do not match, the comparison circuit 135 sets an error flag in step S8 and outputs an error signal ERR corresponding to the error flag.

[0054] 9 is a first detailed flow example of step S4. In step S21, the first interface circuit 140 transmits PWM data to the second interface circuit of one of the first light source drivers 200-1 to the n-th light source driver 200-n. In step S22, the first interface circuit 140 determines whether or not the PWM data has been transmitted to all of the light source drivers. If the first interface circuit 140 determines in step S22 that there is still a light source driver to which it has not transmitted PWM data, it returns to step S21 and transmits the PWM data to the second interface circuit of one of the remaining light source drivers. If the first interface circuit 140 determines in step S22 that the PWM data has been transmitted to all of the light source drivers, it proceeds to step S23.

[0055] In step S23, the first interface circuit 140 receives PWM data from the second interface circuit of one of the first light source driver 200-1 to the n-th light source driver 200-n. In step S24, the first interface circuit 140 determines whether or not PWM data has been received from all of the light source drivers. If the first interface circuit 140 determines in step S24 that there is still a light source driver that has not received PWM data, it returns to step S23 and receives PWM data from the second interface circuit of one of the remaining light source drivers. If the first interface circuit 140 determines in step S24 that PWM data has been received from all of the light source drivers, it proceeds to step S5.

[0056] 10 shows a second detailed flow example of step S4. In step S41, the first interface circuit 140 transmits PWM data to the second interface circuit of one of the first light source driver 200-1 to the n-th light source driver 200-n. In step S42, the first interface circuit 140 receives PWM data from the second interface circuit of the light source driver that transmitted the PWM data in step S41.

[0057] In step S43, the first interface circuit 140 determines whether it has transmitted and received PWM data to and from all light source drivers. If the first interface circuit 140 determines in step S43 that there are still light source drivers for which it has not transmitted or received PWM data, it returns to step S41 and transmits PWM data to the second interface circuit of one of the remaining light source drivers. If the first interface circuit 140 determines in step S43 that it has transmitted and received PWM data to and from all light source drivers, it proceeds to step S5.

[0058] 11 shows a first detailed configuration example of the controller 100 when performing a sticking check. The following mainly describes the parts that are different from those in FIG. 3. The controller 100 further includes a luminance data processing circuit 150.

[0059] The luminance data processing circuit 150 performs a process to add a slight fluctuation over time to the luminance data LMD and outputs the result as processed luminance data PLMD. That is, even when the luminance data LMD does not change, the luminance data processing circuit 150 causes the processed luminance data PLMD to fluctuate slightly over time. Specifically, the luminance data processing circuit 150 performs a process to change a predetermined bit of the luminance data LMD at predetermined time intervals. The predetermined bit is, for example, the LSB, but is not limited to this and may be two or more bits, or may not be the least significant bit. LSB stands for least significant bit.

[0060] The control data generation circuit 110 converts the processed luminance data PLMD into control data CTD, and the first interface circuit 140 transmits the control data CTD to the second interface circuit 240 of the light source driver 200. The first error check code generation circuit 131 calculates an error check code from the control data CTD and stores the error check code in the first memory circuit 120 as first comparison data CP1. The second interface circuit 240 transmits the control data CTD stored in the second memory circuit 230 to the first interface circuit 140 as CTD_RB. The second error check code generation circuit 132 calculates an error check code from the control data CTD_RB and outputs the error check code as second comparison data CP2. The comparison circuit 135 compares the first comparison data CP1 and the second comparison data CP2.

[0061] 12 shows a second detailed configuration example of the controller 100 when performing a sticking check. The following mainly describes the parts that are different from those in FIG. 4. The controller 100 further includes a luminance data processing circuit 150.

[0062] The operation of the luminance data processing circuit 150 and the operation until the first interface circuit 140 receives the control data CTD_RB are the same as those shown in FIG. 11. The first error check code generation circuit 131 calculates an error check code from the processed luminance data PLMD and stores the error check code in the first storage circuit 120 as first comparison data CP1. The conversion circuit 136 converts the control data CTD_RB into luminance data LMD_RB. If there is no error, this luminance data LMD_RB matches the processed luminance data PLMD. The second error check code generation circuit 132 calculates an error check code from the luminance data LMD_RB and outputs the error check code as second comparison data CP2. The comparison circuit 135 compares the first comparison data CP1 with the second comparison data CP2.

[0063] The luminance data processing circuit 150 can also be applied to the configuration examples of FIG. 5 or FIG. 6. When applied to FIG. 5, the processed luminance data PLMD is input to the control data generation circuit 110. The first comparison data CP1 is control data CTD generated from the processed luminance data PLMD. When applied to FIG. 6, the processed luminance data PLMD is input to the control data generation circuit 110 and the first memory circuit 120. The first comparison data CP1 is the processed luminance data PLMD.

[0064] FIG. 13 shows a configuration example of the controller 100 to explain the operation of the controller 100 when an error is detected. The controller 100 may include a dimming processing circuit 170. The controller 100 may also include a third interface circuit 160. An active error signal ERR indicates that an error has been detected. Four operation examples will be described below, but any one, any two, or any three of the four operation examples may be implemented.

[0065] When an active error signal ERR is input, the control data generation circuit 110 generates control data CTD that turns off the light source 300. That is, the control data generation circuit 110 generates control data CTD that sets the brightness of the light source 300 to zero, regardless of the brightness indicated by the brightness data LMD. For example, PWM data with an on-time of zero or current value data with a current value of zero is generated. This turns off the light source 300 when an error is detected.

[0066] The dimming processing circuit 170 generates brightness data LMD through dimming processing. The dimming processing is, for example, local dimming processing based on image data or dimming processing based on the output of an ambient light sensor. When an active error signal ERR is input, the dimming processing circuit 170 stops the dimming processing and outputs brightness data LMD of a given value. The brightness data LMD of the given value may be, for example, brightness data for keeping the light source 300 lit at a constant brightness, or brightness data indicating zero brightness. As a result, the light source 300 is turned on at a constant brightness or turned off when an error is detected.

[0067] When an active error signal ERR is input, the first interface circuit 140 transmits a signal EN to the light source driver 200 to turn off the driving of the light source 300 by the light source driver 200. The signal EN may be received by the second interface circuit 240 of the light source driver 200, or may be received by a terminal input of the light source driver 200. Upon receiving the signal EN, the driving circuit 250 of the light source driver 200 stops driving, and the light source 300 is turned off. As a result, the light source 300 is turned off when an error is detected.

[0068] The third interface circuit 160 communicates with the host device 400 of the controller 100. The host device 400, for example, performs operation settings for the controller 100, transmits brightness data LMD to the controller 100 when the host device 400 performs dimming, or transmits image data to the controller 100 when the controller 100 performs local dimming of the display device. The host device 400 is, for example, a processor such as a microcomputer or a CPU. When an active error signal ERR is input, the third interface circuit 160 may transmit the error signal ERR to the host device 400. Various transmission methods are possible, and the error signal ERR may be transmitted via, for example, SPI or I2C, or via a pin input such as an interrupt signal. When the host device 400 receives an active error signal ERR, it performs error processing. For example, the host device 400 may control the controller 100 or the light source driver 200 to turn off the light source 300 or turn it on at a constant brightness, or may stop the process of sending brightness data, image data, etc. to the controller 100.

[0069] 14 shows an example of the configuration of an electronic device 900 when the controller 100 performs local dimming processing. The electronic device 900 includes a host device 400 and a display system 800. Examples of the electronic device 900 include an in-vehicle display device, a television device, a head-mounted display, or an information processing device having a display. Examples of in-vehicle display devices include a meter panel, a center information display, a head-up display, or an electronic mirror.

[0070] The display system 800 includes a controller 100, a light source driver 200, a backlight 810, a display panel 820, a display driver 830, and a display controller 850. The controller 100 and the light source driver 200 correspond to the light source control system 10 in FIG. 1, 2, or 7. The light source included in the backlight 810 corresponds to the light source 300 in FIG. 1 or 7, or the light sources 300-1 to 300-n in FIG. 7.

[0071] In a plan view of the backlight 810, light sources are arranged two-dimensionally in the backlight 810. In local dimming processing, the light intensity of each of the two-dimensionally arranged light sources is controlled independently of one another. One example of a two-dimensional arrangement of light sources is a matrix arrangement in which a light source is arranged at every intersection of multiple rows and multiple columns. However, the two-dimensional arrangement is not limited to a matrix arrangement. For example, the two-dimensional arrangement may be an arrangement known as a diamond arrangement or a staggered arrangement.

[0072] The light source driver 200 receives PWM data PWMD as control data CTD from the controller 100, and drives each light source of the backlight 810 based on the PWM data PWMD. Note that multiple light source drivers may be provided as shown in FIG.

[0073] The display panel 820 is an electro-optical panel that transmits light from the backlight 810 and displays an image by controlling the transmittance of the light. For example, the display panel 820 is a liquid crystal display panel.

[0074] The display controller 850 receives image data IMB from the controller 100, and transmits the image data IMB and a timing control signal that controls the display timing to the display driver 830. The display controller 850 may perform image processing such as gradation correction, white balance correction, or enlargement / reduction on the received image data IMB.

[0075] The display driver 830 drives the display panel 820 based on the received image data and timing control signals, thereby causing the display panel 820 to display an image.

[0076] The host device 400 transmits image data IMA to the controller 100. The controller 100 receives the image data IMA and performs local dimming processing of the backlight 810 based on the image data IMA. The controller 100 adjusts the light emission brightness of each light source of the backlight 810 according to the brightness of the image data IMA, converts the brightness data LMD obtained by the dimming into PWM data PWMD, and outputs the PWM data PWMD to the light source driver 200. The controller 100 also performs color correction on the image data IMA based on the brightness data LMD, and outputs the color-corrected image data IMB to the display controller 850.

[0077] Fig. 15 shows a detailed configuration example of the controller 100 when performing local dimming processing. The controller 100 further includes a dimming processing circuit 170. Note that the first storage circuit, the error detection circuit, and the first interface circuit are not shown in Fig. 15.

[0078] The light adjustment processing circuit 170 performs local dimming processing based on the image data IMA. The light adjustment processing circuit 170 includes a light source luminance determination circuit 171, an illumination luminance calculation circuit 172, and a color correction circuit 173.

[0079] The light source luminance determination circuit 171 performs dimming processing using the image data IMA to determine luminance data LMD indicating the emission luminance of each light source of the backlight 810, and outputs the luminance data LMD to the control data generation circuit 110 and the illumination luminance calculation circuit 172. Various known local dimming methods may be adopted as a method for determining the luminance data LMD from the image data IMA. As an example, the light source luminance determination circuit 171 may generate the luminance data LMD for each light source by down-sampling the image data IMA to image data in which one pixel corresponds to each light source.

[0080] Based on the luminance data LMD of each light source, the illumination luminance calculation circuit 172 calculates the luminance of light reaching each pixel of the display panel 820 from each light source of the backlight 810. Data indicating the luminance of light reaching each pixel will be referred to as illumination luminance data.

[0081] The color correction circuit 173 performs color correction on the image data IMA based on the illumination luminance data, and outputs the corrected image data IMB to the display driver 830. Specifically, the color correction circuit 173 divides the pixel data of each pixel of the image data IMA by the illumination luminance data of that pixel, and sets the result as the pixel data of each pixel of the image data IMB.

[0082] 3, the error detection circuit 130 may include a first error check code generation circuit 131 that generates an error check code from the control data CTD generated by the control data generation circuit 110 and stores the error check code as first comparison data CP1 in the first storage circuit 120. The error detection circuit 130 may also include a second error check code generation circuit 132 that generates an error check code from the control data CTD_RB received by the first interface circuit 140 and outputs the error check code as second comparison data CP2, and a comparison circuit 135 that compares the first comparison data CP1 and the second comparison data CP2 and outputs the comparison result as an error signal ERR.

[0083] According to this embodiment, the control data CTD_RB read from the light source driver 200 can be error checked by calculating error check codes from the control data CTD and CTD_RB as the first comparison data CP1 and the second comparison data CP2 and comparing them.

[0084] 4, the error detection circuit 130 may include a first error check code generation circuit 131 that generates an error check code from the luminance data LMD input to the control data generation circuit 110 and stores the error check code as first comparison data CP1 in the first storage circuit 120. The error detection circuit 130 may also include a conversion circuit 136 that converts the control data CTD_RB received by the first interface circuit 140 into luminance data LMD_RB. The error detection circuit 130 may also include a second error check code generation circuit 132 that generates an error check code from the luminance data LMD_RB output by the conversion circuit 136 and outputs the error check code as second comparison data CP2, and a comparison circuit 135 that compares the first comparison data CP1 and the second comparison data CP2 and outputs the comparison result as an error signal ERR.

[0085] According to this embodiment, the error check codes are calculated from the luminance data LMD and LMD_RB as the first comparison data CP1 and the second comparison data CP2, and the error check can be performed on the control data CTD_RB read from the light source driver 200 by comparing them.

[0086] 5, the first storage circuit 120 may store the control data CTD generated by the control data generation circuit 110 as the first comparison data CP1. The first interface circuit 140 may receive the control data CTD_RB from the light source driver 200 as the second comparison data CP2. The error detection circuit 130 may include a comparison circuit 135 that compares the first comparison data CP1 and the second comparison data CP2 and outputs the comparison result as an error signal ERR.

[0087] According to this embodiment, the control data CTD and CTD_RB are used as the first comparison data CP1 and the second comparison data CP2 instead of the error check code, and by comparing them, the control data CTD_RB read out from the light source driver 200 can be checked for errors.

[0088] 6, the first storage circuit 120 may store the luminance data LMD input to the control data generation circuit 110 as the first comparison data CP1. The error detection circuit 130 may include a conversion circuit 136 that converts the control data CTD_RB received by the first interface circuit 140 into luminance data LMD_RB and outputs the converted luminance data LMD_RB as the second comparison data CP2. The error detection circuit 130 may also include a comparison circuit 135 that compares the first comparison data CP1 with the second comparison data CP2 and outputs the comparison result as an error signal ERR.

[0089] According to this embodiment, the luminance data LMD and LMD_RB are used as the first comparison data CP1 and the second comparison data CP2 instead of the error check code, and by comparing them, the control data CTD_RB read out from the light source driver 200 can be checked for errors.

[0090] 7 to 9, the first interface circuit 140 may transmit the control data CTD to the first light source driver 200-1 to the n-th light source driver 200-n, including the light source driver 200, and then receive the control data CTD_RB from the first light source driver 200-1 to the n-th light source driver 200-n, where n is an integer of 2 or greater.

[0091] As described in Figures 7, 8 and 10, the first interface circuit 140 may sequentially transmit and receive control data CTD, CTD_RB to the first light source driver 200-1 among the first light source driver 200-1 to the n-th light source driver 200-n including the light source driver 200, transmit and receive control data CTD, CTD_RB to the second light source driver 200-2, ..., transmit and receive control data CTD, CTD_RB to the n-th light source driver 200-n.

[0092] In this embodiment, the control data CTD is written to the second memory circuit 230 and then read out, so the control data CTD and CTD_RB cannot be transmitted and received simultaneously. According to this embodiment, when the controller 100 controls a plurality of light source drivers 200-1 to 200-n, the control data CTD can be transmitted and then the control data CTD_RB can be received.

[0093] In this embodiment, the first interface circuit 140 may transmit and receive the control data CTD and CTD_RB in each frame. The error detection circuit 130 may compare the first comparison data CP1 with the second comparison data CP2 in each frame.

[0094] According to this embodiment, if there is a frame in which an error occurs in the control data CTD, CTD_RB, the error can be detected immediately.

[0095] As described with reference to FIG. 13, the control data generation circuit 110 may generate control data CTD for turning off the light source 300 when an error is detected by the error detection circuit 130.

[0096] 13, the controller 100 may also include a dimming processing circuit 170 that generates luminance data LMD through dimming processing. When an error is detected by the error detection circuit 130, the dimming processing circuit 170 may stop the dimming processing and output luminance data LMD of a given value.

[0097] As described in FIG. 13, when an error is detected by the error detection circuit 130, the first interface circuit 140 may send a signal EN to the light source driver 200 to turn off the driving of the light source 300 by the light source driver 200.

[0098] 13, the controller 100 may also include a third interface circuit 160 that communicates with a host device 400 of the controller 100. The third interface circuit 160 may send an error signal ERR to the host device 400 when an error is detected by the error detection circuit 130.

[0099] According to these embodiments, various processes can be executed when an error is detected. For example, the light source 300 can be turned off or kept on at a constant brightness. Turning the light source 300 off or on can be selected appropriately depending on the purpose. For example, in a head-up display, if the light source is turned on at an abnormal brightness, the visibility of the real space that is normally visible through the screen may be reduced. In such a case, the light source 300 can be turned off when an error is detected. Alternatively, in an in-vehicle cluster panel or the like, the light source 300 may be turned on when an error is detected, with priority given to displaying a warning light.

[0100] 14 and 15, the controller 100 may also include a dimming processing circuit 170. The dimming processing circuit 170 may receive image data IMA for displaying an image on a display panel 820 to which light is incident from a plurality of light sources including the light source 300, and may perform local dimming processing based on the image data IMA to generate luminance data LMD for each of the plurality of light sources. The plurality of light sources including the light source 300 correspond to a backlight 810 in the example of FIG. 14.

[0101] According to this embodiment, brightness data LMD is generated by local dimming processing, control data CTD is generated from the brightness data LMD and sent to the light source driver 200, the control data CTD_RB is read from the light source driver 200, and error detection of the control data CTD_RB can be performed.

[0102] Although the present embodiment has been described in detail above, those skilled in the art will readily understand that many modifications are possible without substantially departing from the novel features and advantages of the present disclosure. Therefore, all such modifications are intended to be within the scope of the present disclosure. For example, a term described at least once in the specification or drawings with a different term having a broader or equivalent meaning may be replaced with that different term anywhere in the specification or drawings. Furthermore, all combinations of the present embodiment and modifications are also within the scope of the present disclosure. Furthermore, the configurations and operations of the controller, light source driver, light source control system, light source, host device, backlight, display panel, display controller, display driver, display system, electronic device, etc. are not limited to those described in the present embodiment, and various modifications are possible. [Explanation of symbols]

[0103] 10...light source control system, 100...controller, 110...control data generation circuit, 120...first memory circuit, 130...error detection circuit, 131...first error check code generation circuit, 132...second error check code generation circuit, 135...comparison circuit, 136...conversion circuit, 140...first interface circuit, 150...luminance data processing circuit, 160...third interface circuit, 170...dimming processing circuit, 171...light source luminance determination circuit, 172...illumination luminance calculation circuit, 173...color correction circuit, 200...light source driver, 200-1 ~200-n...first light source driver to n-th light source driver, 230...second memory circuit, 240...second interface circuit, 300...light source, 400...host device, 800...display system, 810...backlight, 820...display panel, 830...display driver, 850...display controller, 900...electronic device, CP1...first comparison data, CP2...second comparison data, CTD, CTD_RB...control data, ERR...error signal, IMA, IMB...image data, LMD, LMD_RB...luminance data, PLMD...processed luminance data

Claims

1. a controller that transmits control data to a light source driver that drives the light source based on the control data to control the brightness of the light source, a control data generating circuit that generates the control data based on luminance data indicating the luminance; a first interface circuit for transmitting the control data to the light source driver; a first storage circuit that stores first comparison data based on the luminance data or the control data; an error detection circuit that performs error detection using the stored first comparison data; Including, The light source driver a second interface circuit for receiving the control data; a second storage circuit for storing the received control data; a drive circuit that drives the light source based on the stored control data; Including, The first interface circuit receiving the control data stored in the second storage circuit from the second interface circuit; The error detection circuit A controller characterized by detecting errors in the control data received from the light source driver by comparing the first comparison data with second comparison data based on the control data received from the light source driver.

2. 2. The controller according to claim 1, The first comparison data and the second comparison data are A controller characterized by an error check code generated from the control data, an error check code generated from the luminance data, the control data, or the luminance data.

3. 2. The controller according to claim 1, The control data is A controller characterized in that the data is PWM data indicating a pulse width of a pulse signal that drives the light source, or current value data indicating a current value that drives the light source.

4. 2. The controller according to claim 1, The error detection circuit a first error check code generation circuit that generates an error check code from the control data generated by the control data generation circuit and stores the error check code in the first storage circuit as the first comparison data; a second error check code generation circuit that generates an error check code from the control data received by the first interface circuit and outputs the error check code as the second comparison data; a comparison circuit that compares the first comparison data with the second comparison data and outputs a result of the comparison as an error signal; A controller comprising:

5. 2. The controller according to claim 1, The error detection circuit a first error check code generation circuit that generates an error check code from the luminance data input to the control data generation circuit and stores the error check code in the first storage circuit as the first comparison data; a conversion circuit that converts the control data received by the first interface circuit into the luminance data; a second error check code generation circuit that generates an error check code from the luminance data output by the conversion circuit and outputs the error check code as the second comparison data; a comparison circuit that compares the first comparison data with the second comparison data and outputs a result of the comparison as an error signal; A controller comprising:

6. 2. The controller according to claim 1, The first memory circuit storing the control data generated by the control data generation circuit as the first comparison data; The first interface circuit receiving the control data from the light source driver as the second comparison data; The error detection circuit a comparison circuit that compares the first comparison data with the second comparison data and outputs a result of the comparison as an error signal;

7. 2. The controller according to claim 1, The first memory circuit storing the luminance data input to the control data generation circuit as the first comparison data; The error detection circuit a conversion circuit that converts the control data received by the first interface circuit into luminance data and outputs the converted luminance data as the second comparison data; a comparison circuit that compares the first comparison data with the second comparison data and outputs a result of the comparison as an error signal; A controller comprising:

8. 2. The controller according to claim 1, The first interface circuit A controller characterized by transmitting the control data to a first light source driver to an nth light source driver (n is an integer greater than or equal to 2) including the light source driver, and then receiving the control data from the first light source driver to the nth light source driver.

9. 2. The controller according to claim 1, The first interface circuit A controller characterized by sequentially transmitting and receiving the control data to the first light source driver among the first light source driver to the nth light source driver (n is an integer of 2 or more) including the light source driver, transmitting and receiving the control data to the second light source driver, ..., transmitting and receiving the control data to the nth light source driver.

10. 2. The controller according to claim 1, The first interface circuit transmitting and receiving the control data in each frame; The error detection circuit A controller that compares the first comparison data with the second comparison data in each frame.

11. 2. The controller according to claim 1, a luminance data processing circuit that performs processing to change predetermined bits of the luminance data at predetermined time intervals and outputs processed luminance data that is a result of the processing to the control data generation circuit; The first memory circuit a controller storing the first comparison data based on the processed luminance data or the control data;

12. 2. The controller according to claim 1, The control data generation circuit a controller that generates the control data to turn off the light source when an error is detected by the error detection circuit;

13. 2. The controller according to claim 1, a light control processing circuit for generating the luminance data by light control processing; The dimming processing circuit When an error is detected by the error detection circuit, the controller stops the dimming process and outputs brightness data of a given value.

14. 2. The controller according to claim 1, The first interface circuit When an error is detected by the error detection circuit, the controller sends a signal to the light source driver to turn off driving of the light source by the light source driver.

15. 2. The controller according to claim 1, a third interface circuit for communicating with a host device of the controller; The third interface circuit a controller that transmits an error signal to the host device when an error is detected by the error detection circuit;

16. 2. The controller according to claim 1, A controller characterized by including a dimming processing circuit that receives image data for displaying an image on a display panel to which light is incident from a plurality of light sources including the light source, and performs local dimming processing based on the image data to generate the brightness data for each of the plurality of light sources.

17. A controller according to claim 1; the light source driver; A light source control system comprising:

18. A controller according to claim 1; the light source driver; the light source; a display panel onto which light from the light source is incident; A display system comprising:

Images