Display device, display system, display device control method, and display system control method

Abstract

To detect erroneous lighting and circuit abnormality in two display devices which can illuminate each of two display sections arranged in a steering wheel.SOLUTION: A display device is used as a first display device, of the first display device and a second display device which are arranged in a steering wheel. The display device includes: a first light emitting diode which illuminates a first display section; a first power control section which controls power supply to the first light emitting diode; a first lighting control section which performs lighting control of the first light emitting diode; a first monitoring circuit which monitors a first lighting state of the first light emitting diode; a first abnormality determination section which determines an abnormality of the first lighting state on the basis of an output of the first monitoring circuit; and a first permission control section which controls permission or non-permission of the power supply to a second light emitting diode of the display device to be used as the second display device on the basis of a determination result of the first abnormality determination section.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a display device, a display system, a control method for a display device, and a control method for a display system. [Background technology]

[0002] Conventionally, there have been LED lighting monitoring and control systems that monitor the lighting state, lighting abnormalities, and circuit abnormalities of LEDs, output monitoring signals to an external host device, and enable lighting control of the lamp using external signals from the host device (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-3864 Summary of the Invention [Problem to be solved by the invention]

[0004] However, there is no disclosure that two display devices control each other to allow the other to turn on the LED, thereby detecting erroneous lighting or circuit abnormalities and forcibly turning off the LED.

[0005] Therefore, the object of the present invention is to provide a display device, a display system, a control method for a display device, and a control method for a display system, in which two display devices capable of illuminating two display sections respectively arranged on a steering wheel mutually control the turning on or off of light-emitting diodes that illuminate the display sections, thereby indirectly monitoring each other and forcibly turning off the light-emitting diodes if erroneous lighting or a circuit abnormality is detected. [Means for solving the problem]

[0006] A display device according to an embodiment of the present disclosure is a display device used as the first display device of a first display device and a second display device arranged on a steering wheel, and includes: a first light-emitting diode that illuminates a first display unit; a first power control unit that controls the supply of power to the first light-emitting diode; a first lighting control unit that controls the lighting of the first light-emitting diode; a first monitoring circuit that monitors a first lighting state of the first light-emitting diode; a first abnormality determination unit that determines an abnormality in the first lighting state based on the output of the first monitoring circuit; and a first permission control unit that controls whether to allow or disallow the supply of power to the second light-emitting diode of the display device used as the second display device based on the determination result of the first abnormality determination unit. [Effects of the Invention]

[0007] By mutually controlling the permission of two display devices capable of illuminating two display sections respectively arranged on a steering wheel, it is possible to provide a display device, a display system, a control method for a display device, and a control method for a display system that can suppress erroneous lighting without having a multiplexing structure to prevent malfunction. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram showing a steering wheel 10 on which a display system 100S according to an embodiment is mounted. [Figure 2] 2 is a block diagram showing an example of the configuration of an in-vehicle system 200. FIG. [Figure 3] FIG. 2 is a diagram showing an example of the circuit configuration of display devices 100L and 100R. [Figure 4] 10 is a flowchart showing processing executed by display devices 100L and 100R of a display system 100S. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments to which the display device, display system, display device control method, and display system control method of the present disclosure are applied will be described.

[0010] <Embodiment> FIG. 1 is a view of a steering wheel 10 equipped with a display system 100S according to an embodiment, as viewed from the driver's seat side. The display system 100S includes display devices 100L and 100R. As shown in FIG. 1, the steering wheel 10 is mounted on a vehicle, for example, and the display devices 100L and 100R are respectively mounted inside left and right spokes 11. The display devices 100L and 100R have display units 101L and 101R, respectively, which are exposed on the surfaces of the left and right spokes 11. The left and right directions refer to the right and left sides of the paper in FIG. 1.

[0011] The display device 100L provided on the left spoke 11 is an example of a first display device, and the display device 100R provided on the right spoke 11 is an example of a second display device.

[0012] Display unit 101L is an example of a first display unit, and display unit 101R is an example of a second display unit. Note that, since display devices 100L and 100R have the same configuration, display device 100R may be an example of a first display device and display unit 101R may be an example of the first display unit, and display device 100L may be an example of a second display device and display unit 101L may be an example of the second display unit.

[0013] The display devices 100L and 100R each have an LED (light emitting diode). The LED is located on the rear side of the display units 101L and 101R, respectively. The rear side of the display units 101L and 101R is the rear side in a direction perpendicular to the paper surface of FIG. 1, and is the inside side of the spoke 11 opposite the driver's seat side of the display units 101L and 101R.

[0014] Display units 101L and 101R have translucent portions that represent the shapes of symbols and indicators that indicate the operating status of devices mounted on the vehicle, and are configured so that when illuminated by an LED on the backside, the transmitted light makes the symbols and indicators appear lit from the driver's seat side. Symbols are letters or symbols that indicate the operating status of devices mounted on the vehicle. Here, a description is given of a configuration in which the symbols on display units 101L and 101R are the same, but the symbols on display units 101L and 101R may be different. Indicators are letters or symbols that indicate the status of each part of the vehicle.

[0015] <Configuration of the in-vehicle system 200 including the display devices 100L and 100R> 2 is a block diagram showing an example of the configuration of the in-vehicle system 200. The in-vehicle system 200 includes display devices 100L and 100R and a master device 210. The master device 210 is, for example, an ECU (electronic control unit) mounted on a vehicle, and controls the display devices 100L and 100R to turn on or off LEDs 110L and 110R. The display devices 100L and 100R and the master device 210 are communicatively connected via, for example, a local interconnect network (LIN).

[0016] The display devices 100L and 100R (display system 100S) are devices whose basic lighting state is when both LEDs 110L and 110R are lit (turned on). The lighting state of LED 110L at a brightness based on an instruction from master device 210 is an example of a first lighting state, and the lighting state of LED 110R at a brightness based on an instruction from master device 210 is an example of a second state.

[0017] The lighting of LEDs 110L and 110R that is not in the first lighting state or the second lighting state based on an instruction from master device 210 is an example of an abnormal lighting state.

[0018] <Configuration of display device 100L> The display devices 100L and 100R have the same configuration. The display device 100L includes an LED 110L, a power control circuit 120L, a lighting control circuit 130L, a monitoring circuit 140L, an MCU (microcontroller unit) 150L, ​​and an enable signal output unit (EN signal output unit) 155L. Similarly, the display device 100R includes an LED 110R, a power control circuit 120R, a lighting control circuit 130R, a monitoring circuit 140R, an MCU 150R, and an enable signal output unit (EN signal output unit) 155R.

[0019] The LED 110L is an example of a first light-emitting diode, the power control circuit 120L is an example of a first power control unit, and the MOSFET 131L of the lighting control circuit 130L and the drive control unit 151L of the MCU 150L are an example of a first lighting control unit. The monitoring circuit 140L is an example of a first monitoring circuit. The LED 110R is an example of a second light-emitting diode, the power control circuit 120R is an example of a second power control unit, and the MOSFET 131R of the lighting control circuit 130R and the drive control unit 151R of the MCU 150R are an example of a second lighting control unit. The monitoring circuit 140R is an example of a second monitoring circuit. Note that the display device 100R may be an example of a first display device and the display unit 101R may be an example of a first display unit, in which case the first and second of each component may be interchanged.

[0020] Here, explanation will be made using FIG. 3 in addition to FIG. 2. FIG. 3 is a diagram showing an example of the circuit configuration of the display devices 100L and 100R. Since the circuit configurations of the display devices 100L and 100R are the same, only the display device 100L will be explained here. FIG. 3 shows a power supply terminal 20. The power supply terminal 20 is connected to a power source such as a vehicle battery, and is a terminal to which, for example, 12V DC power is supplied.

[0021] The display devices 100L and 100R have the same configuration, and the terminal 125L of the display device 100L is connected to the terminal 126R of the display device 100R and receives the enable signal output from the enable signal output unit 155R. The terminal 125R of the display device 100R is also connected to the terminal 126L of the display device 100L and receives the enable signal output from the enable signal output unit 155L.

[0022] The LED 110L is connected between the power supply terminal 20 and the ground, which is an example of a reference potential point. The line between the power supply terminal 20 to which the LED 110L is connected and the ground is a current supply path that supplies current to the LED 110L, and is an example of a first current supply path.

[0023] The power control circuit 120L includes a PNP transistor 121L. The transistor 121L is an example of a first power control element. The transistor 121L has an emitter connected to the power supply terminal 20, a collector connected to the anode of the LED 110L, and a base connected to a terminal 125L. The terminal 125L is connected to an enable signal output unit 155R of the display device 100R via a terminal 126R. A resistor R62 is connected between the emitter and base of the transistor 121L to ensure proper operation of the transistor 121L, a resistor R14 is connected between the collector and the anode of the LED 110L to ensure an appropriate current flows through the LED 110L, and a resistor R63 is connected between the base and the terminal 125L to properly limit the base current of the transistor 121L.

[0024] When the power control circuit 120L is turned on by an enable signal output from the enable signal output unit 155R of the display device 100R via the terminal 126R to the terminal 125L, the power control circuit 120L enables power to be supplied to the LED 110L from the power supply terminal 20, and when the power control circuit 120L is turned off by an enable signal output from the enable signal output unit 155R of the display device 100R via the terminal 126R to the terminal 125L, the power control circuit 120L disables power supply to the LED 110L from the power supply terminal 20. In this way, the power control circuit 120L controls the power supply to the LED 110L.

[0025] The lighting control circuit 130L has a MOSFET (metal oxide semiconductor field effect transistor) 131L. The MOSFET 131L is an example of a first lighting switching element connected in series with the LED 110L. The MOSFET 131L has a drain connected to the cathode of the LED 110L, a source connected to ground, and a gate connected to the MCU 150L. To ensure proper operation of the MOSFET 131L, a resistor R51 is connected between the gate and source, and a resistor R50 is connected between the gate and the MCU 150L.

[0026] The lighting control circuit 130L controls the lighting of the LED 110L by PWM (pulse width modulation) driving of the MOSFET 131L by the drive control unit 151L of the MCU 150L when the power control circuit 120L can supply power to the LED 110L from the power supply terminal 20. In addition to controlling the lighting or extinguishing, lighting control by PWM driving can also adjust the brightness of the LED 110L by changing the duty ratio.

[0027] The monitoring circuit 140L is connected between the anode of the LED 110L and the MCU 150L, ​​and monitors the lighting state of the LED 110L by monitoring the voltage applied to the LED 110L. The monitoring circuit 140L converts the current flowing through the anode of the LED 110L into a voltage and inputs it to the MCU 150L as a lighting state signal indicating the lighting state. The lighting state signal is used to monitor for abnormalities in the lighting state of the LED 110L.

[0028] The MCU 150L is a microcontroller realized by a computer including a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), an input / output interface, an internal bus, etc. The MCU 150L has a drive control unit 151L, an abnormality determination unit 152L, and a permission control unit 153L.

[0029] The drive control unit 151L, the abnormality determination unit 152L, and the permission control unit 153L of the MCU 150L are examples of a first drive control unit, a first abnormality determination unit, and a first permission control unit, respectively. The drive control unit 151L, the abnormality determination unit 152L, and the permission control unit 153L are functional blocks that represent the functions of a program executed by the MCU 150L.

[0030] The drive control section 151L sets a PWM duty ratio based on a lighting control signal transmitted from the master device 210, and performs PWM driving of the LED 110L.

[0031] The abnormality determination unit 152L determines whether there is an abnormality in the lighting state of the LED 110L based on the lighting state signal input from the monitoring circuit 140L. The abnormality determination unit 152L constantly monitors even when no abnormality has occurred. The abnormality determination unit 152L determines that the lighting state of the LED 110L is normal (not abnormal) when power is supplied to the LED 110L from the power supply terminal 20 by the power control circuit 120L, the drive control unit 151L is PWM-driving the LED 110L, and the LED 110L is lighting at a predetermined brightness.

[0032] Furthermore, the abnormality determination unit 152L determines that the lighting state of the LED 110L is abnormal, for example, when the LED 110L is lit even though power is being supplied to the LED 110L from the power supply terminal 20 by the power control circuit 120L but PWM driving of the LED 110L is not being performed by the drive unit control unit 151L. The abnormality determination unit 152L also determines that the lighting state of the LED 110L is abnormal when the LED 110L is lit even though power is not being supplied to the LED 110L from the power supply terminal 20 by the power control circuit 120L, or when power is being supplied to the LED 110L from the power supply terminal 20 by the power control circuit 120L and the LED 110L is not lit when PWM driving of the LED 110L is being performed by the drive control unit 151L.

[0033] The permission control unit 153L controls whether to permit or prohibit the supply of power to the LED 110R of the display device 100R based on the determination result of the abnormality determination unit 152L. The permission control unit 153L causes the enable signal output unit 155L to output an enable signal to permit the supply of power to the LED 110R of the display device 100R, except when the display device 100L is initialized immediately after the vehicle ignition is turned on or when the abnormality determination unit 152L determines that the lighting state of the LED 110L is abnormal. The enable signal is output to the terminal 125R of the display device 100R via the terminal 126L and input to the base of the PNP transistor 121R of the power control circuit 120R to control the transistor 121R. As a result, the enable signal turns on the transistor 121R of the power control circuit 120R of the display device 100R, enabling the supply of power to the LED 110R from the power supply terminal 20.

[0034] On the other hand, when the abnormality determination unit 152L determines that the lighting state of the LED 110L is abnormal, the permission control unit 153L prevents the enable signal output unit 155L from outputting an enable signal in order to prohibit the supply of power to the LED 110R of the display device 100R. As a result, the enable signal turns off the transistor 121R of the power control circuit 120R of the display device 100R, making it impossible to supply power to the LED 110R from the power supply terminal 20, and the LED 110R is forcibly turned off.

[0035] As a result, even though the MCU 150R of the display device 100R recognizes the lighting state as normal through the lighting state signal from the monitoring circuit 140R, the LED 110R is in an off state, so the abnormality determination unit 152R determines that there is an abnormality, and the permission control unit 153R prevents the enable signal output unit 155R from outputting an enable signal. As a result, power supply to the LED 110L of the display device 100L becomes impossible, and the LED 110L is forcibly turned off.

[0036] The enable signal output unit 155L is connected between the MCU 150L and the terminal 126L and includes an NPN transistor 156L. The transistor 156L has a collector connected to the terminal 126L, an emitter connected to ground, and a base connected to the MCU 150L. The voltage of the base is controlled by the permission control unit 153L.

[0037] When the permission control unit 153L turns on the transistor 156L, the enable signal output unit 155L outputs an enable signal to the power control circuit 120R via the terminal 126L, which is then output to the terminal 125R of the display device 100R. On the other hand, when the permission control unit 153L turns off the transistor 156L, the enable signal output unit 155L stops outputting the enable signal. When the output of the enable signal is stopped, the transistor 121R of the power control circuit 120R is turned off.

[0038] 2 and 3, the display device 100L has been described, but the display devices 100L and 100R have the same configuration and are symmetrically connected by connecting the terminal 125L to the terminal 126R and by connecting the terminal 126L to the terminal 125R. Therefore, the display device 100R operates in the same manner as described above for the display device 100L.

[0039] In the display device 100R, the power control circuit 120R includes a PNP transistor 121R. The transistor 121R is an example of a second power control element. The lighting control circuit 130R includes a MOSFET 131R. The MOSFET 131R is an example of a second lighting switching element connected in series to the LED 110R.

[0040] The MCU 150R also has a drive control unit 151R, an abnormality determination unit 152R, and a permission control unit 153R. The drive control unit 151R, the abnormality determination unit 152R, and the permission control unit 153R are examples of a second drive control unit, a second abnormality determination unit, and a second permission control unit, respectively. The MOSFET 131R and the drive control unit 151R are examples of a second lighting control unit. The enable signal output unit 155R is connected between the MCU 150R and the terminal 126R, and has an NPN transistor 156R.

[0041] The display devices 100L and 100R are devices that have a basic lighting state in which both the LEDs 110L and 110R are lit, and do not allow only one of the LEDs 110L and 110R to be lit.

[0042] To achieve this, the display devices 100L and 100R mutually control whether to allow or disallow the output of enable signals to each other to switch between allowing and disallowing the lighting of the other's LEDs 110R and 110L, and monitor the lighting status of the LEDs using their respective monitoring circuits 140L and 140R. Therefore, in the event of an abnormality, the LEDs 110L and 110R can be forcibly turned off without requiring control by the master device 210.

[0043] <Flowchart> Fig. 4 is a flowchart showing the processing executed by the display devices 100L and 100R of the display system 100S. In Fig. 4, in order to make the overall flow easier to understand, operations other than the processing executed by the MCUs 150L and 150R are also explained. Also, while the explanation here focuses on the display device 100L, it is similar if the display device 100R is the main focus.

[0044] Immediately after the ignition of the vehicle is turned on, the display devices 100L and 100R are initialized, and the display device 100L is in a state of waiting to receive a lighting control signal from the master device 210 (step S0).

[0045] During initialization, the display devices 100L and 100R and the display system 100S are initialized, and it is confirmed that there are no abnormalities in the display devices 100L and 100R and the display system 100S. If there are no abnormalities, the MCU 150L of the display device 100L and the MCU 150R of the display device 100R output enable signals to each other to allow power supply to the LEDs 110R and 110L.

[0046] The MCU 150L of the display device 100L determines whether or not a signal has been received from the master device 210 (step S1).

[0047] The MCU 150L determines whether the received signal is a lighting control signal (step S2).

[0048] If the MCU 150L determines that the received signal is a lighting control signal (S2: Yes), the MCU 150L further determines whether the received lighting control signal instructs lighting of the LED 110L (step S2A).

[0049] When the MCU 150L determines that the received signal is a lighting control signal and instructs lighting (S2A: Yes), the permission control unit 153L of the display device 100L causes the enable signal output unit 155L to output an enable signal (step S3A). If the enable signal has already been output, the permission control unit 153L causes the enable signal output unit 155L to continue outputting the enable signal. At this time, the abnormality determination unit 152L has determined that the lighting state of the LED 100L is not abnormal.

[0050] The drive control unit 151L sets the PWM duty ratio based on the lighting control signal received from the master device 210, and lights up the LED 110L based on PWM driving (step S4A). If the LED 110L is already being PWM driven, the PWM driving continues.

[0051] The abnormality determination unit 152L acquires the lighting state signal from the monitoring circuit 140L (step S5).

[0052] The abnormality determination unit 152L determines whether or not there is an abnormality in the lighting state of the LED 110L based on the lighting state signal (step S6).

[0053] If the abnormality determination unit 152L determines that the lighting state of the LED 110L is normal (S6: Yes), the process returns to the state of waiting for reception of a lighting control signal (step S0) from the master device 210. On the other hand, if the abnormality determination unit 152L determines that there is an abnormality (S6: No), the permission control unit 153L of the display device 100L does not cause the enable signal output unit 155L to output an enable signal (step S7).

[0054] In step S2, if the MCU 150L determines that the received signal is not a lighting control signal (S2: No), it processes a function other than turning on or off the display units 101L and 101R of the display devices 100L and 100R. The processing of the function may be any processing as long as it is processing of a function related to vehicle control.

[0055] Furthermore, in step S2A, if the MCU 150L determines that the received signal is a lighting control signal and instructs turning off the LED (S2A: No), the permission control unit 153L of the display device 100L does not cause the enable signal output unit 155L to output an enable signal (step S3B). If the enable signal has not already been output, the enable signal is not continuously output. At this time, the abnormality determination unit 152L has determined that the lighting state of the LED 100L is not abnormal.

[0056] In steps S3B and S7, the enable signal output unit 155L of the display device 100L does not output an enable signal, so power is no longer supplied from the power control circuit 120R of the display device 100R to the LED 110R, and the LED 110R is forcibly turned off (step S11).

[0057] In step S11, the LED 110R of the display device 100R is forcibly turned off, and although the MCU 150R of the display device 100R recognizes that the lighting state is normal, the LED 110R is in an off state, so the abnormality determination unit 152R detects an abnormality (step S12).

[0058] The display device 100R notifies the display device 100L that the lighting state of the LED 110R is abnormal. Specifically, the permission control unit 153R turns off the transistor 156R of the enable signal output unit 155R, thereby preventing the enable signal output unit 155R from outputting an enable signal (step S13).

[0059] In step S13, since the enable signal output unit 155R of the display device 100R does not output an enable signal, power supply from the power control circuit 120L of the display device 100L to the LED 110L is stopped, and the LED 110L is forcibly turned off (step S21). This completes the series of processes.

[0060] When the LEDs 110L and 110R are forcibly turned off, for example, the ignition of the vehicle is turned off and then on again to initialize the display device and the display, and to enable the supply of power to the LEDs 110L and 110R, the permission control units 153L and 153R may output an enable signal to the enable signal output units 155L and 155R and enter a state (step S0) waiting for reception of a lighting control signal from the master device 210. Furthermore, for example, if no abnormality occurs after a predetermined time (for example, 10 seconds) has elapsed, the permission control units 153L and 153R may output an enable signal to the enable signal output units 155L and 155R to enable the supply of power to the LEDs 110L and 110R.

[0061] <Effects> As described above, the display device 100L includes a power control circuit 120L that controls the power supply to the LED 110L, a lighting control unit (lighting control circuit 130L and drive control unit 151L) that controls the lighting of the LED 110L, a monitoring circuit 140L that monitors the lighting state of the LED 110L, an abnormality determination unit 152L that determines an abnormality in the lighting state of the LED 110L based on the output of the monitoring circuit 140L, and a permission control unit 153L that controls permission or prohibition of power supply to the LED 110R of the display device 100R based on the determination result of the abnormality in the lighting state of the LED 110L. Therefore, permission or prohibition of power supply to the LED 110R can be controlled based on the determination result of an abnormality in the lighting state of the LED 110L. The same applies to the display device 100R.

[0062] Therefore, in two display devices 100L and 100R capable of illuminating two display units 101L and 101R respectively arranged on the steering wheel 10, by mutually controlling whether or not the light-emitting diodes that illuminate the display units are allowed to light up, it is possible to provide display devices 100L and 100R, display system 100S, a control method for display devices 100L and 100R, and a control method for display system 100S that can suppress erroneous lighting.

[0063] Furthermore, when the determination result of the abnormality determination unit 152L indicates an abnormality in the lighting state of the LED 110L (own side), the permission control unit 153L does not permit the supply of power to the LED 110R, and therefore the LED 110R on the display device 100R side (the other side) can be forcibly turned off. This is also true for the display device 100R. Therefore, the forced turning off of the LEDs 110L and 110R in the event of an abnormality can be quickly achieved without using the control of the master device 210.

[0064] Furthermore, the power control circuit 120L has a transistor 121L in a current supply path that supplies current to the LED 110L, which controls the power supply to the LED 110L, and can switch the transistor 121L on and off depending on whether power supply from the display device 100R is permitted or not, thereby enabling reliable control of the power supply. This is also true for the power control circuit 120R. Therefore, the power control circuits mutually control whether lighting is permitted, and the power supply to the LEDs 110L and 110R can be reliably controlled.

[0065] Furthermore, the lighting control unit of the display device 100L includes a MOSFET 131L connected in series to the LED 110L in a current supply path that supplies current to the LED 110L, and a drive control unit 151L that controls the lighting of the LED 110L by driving the MOSFET 131L. This is similar to the display device 100R. Therefore, when power is supplied to the LEDs 110L and 110R, the MOSFETs 131L and 131R can reliably control the lighting of the LEDs 110L and 110R.

[0066] Furthermore, the drive control unit 151L can adjust the duty ratio when PWM driving the LED 110L. This is also true for the drive control unit 151R. Therefore, it is possible to provide the display devices 100L and 100R that can control the brightness and on / off states of the LEDs 110L and 110R.

[0067] Furthermore, since the display device 100L has the same configuration as the display device 100R, indirect mutual monitoring is possible by mutually controlling whether or not to allow lighting, and erroneous lighting can be suppressed with higher precision by not going through a master device, and it is possible to provide the display devices 100L and 100R, the display system 100S, a control method for the display devices 100L and 100R, and a control method for the display system 100S that quickly and forcibly turn off the light-emitting diodes.

[0068] The above describes exemplary embodiments of the present disclosure, including a display device, a display system, a control method for a display device, and a control method for a display system. However, the present disclosure is not limited to the specifically disclosed embodiments, and various modifications and changes are possible without departing from the scope of the claims. [Explanation of symbols]

[0069] 10. Steering wheel 100L Display device (an example of the first display device) 100R display device (an example of a second display device) 101L Display (example of the first display) 101R Display (example of the second display) 110L LED (example of the first light-emitting diode) 110R LED (an example of a second light-emitting diode) 120L Power control circuit (an example of a first power control unit) 120R Power control circuit (an example of a second power control unit) 121L Transistor (an example of a first power control element) 121R transistor (an example of a second power control element) 130L, 130R lighting control circuit 131L MOSFET (example of the first lighting switching element) 131R MOSFET (an example of a second lighting switching element) 140L Monitoring circuit (example of the first monitoring circuit) 140R Monitoring circuit (example of a second monitoring circuit) 150L, ​​150R MCU 151L Drive control unit (an example of a first drive control unit) 151R drive control unit (an example of a second drive control unit) 152L Abnormality determination unit (example of first abnormality determination unit) 152R Abnormality determination unit (an example of the second abnormality determination unit) 153L permission control unit (an example of a first permission control unit) 153R Permission control unit (an example of a second permission control unit) 155L, 155R Enable signal output section 200 In-Vehicle Systems 210 Master Device

Claims

1. A display device that is disposed on a steering wheel and is used as the first display device of a first display device and a second display device that have the same configuration, a first light-emitting diode that illuminates the first display portion; a first power control unit having a first power control element in a first current supply path that supplies current to the first light emitting diode, the first power control unit controlling the power supply to the first light emitting diode in response to a second enable signal that controls whether or not to allow power supply to the first light emitting diode and is input from the second display device to a first control terminal of the first power control element; a first lighting control unit that controls lighting of the first light emitting diode; a first monitoring circuit that monitors a first lighting state of the first light-emitting diode; a first abnormality determination unit that determines an abnormality in the first lighting state based on an output of the first monitoring circuit; a first permission control unit that outputs a first enable signal to a second control terminal of a second power control element that controls power supply to the second light emitting diode in a second current supply path that supplies current to the second light emitting diode of the display device used as the second display device, based on a determination result of the first abnormality determination unit; and A display device comprising:

2. 2. The display device according to claim 1, wherein the first permission control unit does not permit power supply to the second light-emitting diode of the display device used as the second display device when the judgment result of the first abnormality judgment unit indicates an abnormality in the first lighting state.

3. The first lighting control unit a first lighting switching element connected in series to the first light emitting diode in a first current supply path that supplies current to the first light emitting diode; a first drive control unit that controls lighting of the first light-emitting diode by driving the first lighting switching element; The display device according to claim 1 or 2, comprising:

4. The display device according to claim 3 , wherein the first drive control section is capable of adjusting a duty ratio when driving the first lighting switching element by pulse width modulation.

5. A display system including a first display device and a second display device arranged on a steering wheel and having the same configuration, The first display device is a first light-emitting diode that illuminates the first display portion; a first power control unit having a first power control element in a first current supply path that supplies current to the first light emitting diode, the first power control unit controlling the power supply to the first light emitting diode in response to a second enable signal that controls whether or not to allow power supply to the first light emitting diode and is input from the second display device to a first control terminal of the first power control element; a first lighting control unit that controls lighting of the first light emitting diode; a first monitoring circuit that monitors a first lighting state of the first light-emitting diode; a first abnormality determination unit that determines an abnormality in the first lighting state based on an output of the first monitoring circuit; a first permission control unit that outputs a first enable signal to a second control terminal of a second power control element that controls power supply to the second light emitting diode in a second current supply path that supplies current to the second light emitting diode of the second display device based on a determination result of the first abnormality determination unit; and and The second display device is the second light-emitting diode for illuminating the second display portion; a second power control unit having the second power control element that controls the power supply to the second light-emitting diode in the second current supply path, the second power control unit controlling the power supply to the second light-emitting diode in response to the first enable signal being input from the first display device to the second control terminal of the second power control element; a second lighting control unit that controls lighting of the second light-emitting diode; a second monitoring circuit that monitors a second lighting state of the second light-emitting diode; a second abnormality determination unit that determines an abnormality in the second lighting state based on an output of the second monitoring circuit; a second permission control unit that outputs the second enable signal that controls permission or non-permission of power supply to the first light-emitting diode in the first current supply path of the first display device based on a determination result of the second abnormality determination unit to the first control terminal of the first power control element; A display system comprising:

6. the first permission control unit, when the determination result of the first abnormality determination unit indicates an abnormality in the first lighting state, does not permit power supply to the second light-emitting diode of the second display device; The display system according to claim 5, wherein the second permission control unit does not permit power supply to the first light-emitting diode of the first display device when the judgment result of the second abnormality judgment unit indicates an abnormality in the second lighting state.

7. A method for controlling a display device that is disposed on a steering wheel and is used as the first display device of a first display device and a second display device that have the same configuration, the method comprising: The display device includes: a first light-emitting diode that illuminates the first display portion; a first power control unit having a first power control element in a first current supply path that supplies current to the first light emitting diode, the first power control unit controlling the power supply to the first light emitting diode in response to a second enable signal that controls whether or not to allow power supply to the first light emitting diode and is input from the second display device to a first control terminal of the first power control element; a first lighting control unit that controls lighting of the first light emitting diode; a first monitoring circuit that monitors a first lighting state of the first light-emitting diode; Including, determining whether the first lighting state is abnormal based on an output of the first monitoring circuit; a first enable signal for controlling permission or prohibition of power supply to a second light-emitting diode in a second current supply path that supplies current to the second light-emitting diode of the display device used as the second display device based on a determination result of an abnormality in the first lighting state, the first enable signal being output to a second control terminal of a second power control element that controls power supply to the second light-emitting diode; A method for controlling a display device.

8. A control method for a display system including a first display device and a second display device that are disposed on a steering wheel and have the same configuration, comprising: The first display device is a first light-emitting diode that illuminates the first display portion; a first power control unit having a first power control element in a first current supply path that supplies current to the first light emitting diode, the first power control unit controlling the power supply to the first light emitting diode in response to a second enable signal that controls whether or not to allow power supply to the first light emitting diode and is input from the second display device to a first control terminal of the first power control element; a first lighting control unit that controls lighting of the first light emitting diode; a first monitoring circuit that monitors a first lighting state of the first light-emitting diode; and The second display device is a second light-emitting diode for illuminating the second display portion; a second power control unit having a second power control element in a second current supply path that supplies current to the second light emitting diode, the second power control unit controlling the power supply to the second light emitting diode in response to a first enable signal that controls whether or not to allow power supply to the second light emitting diode to be input from the first display device to a second control terminal of the second power control element; a second lighting control unit that controls lighting of the second light-emitting diode; a second monitoring circuit that monitors a second lighting state of the second light-emitting diode; and The first display device is determining whether the first lighting state is abnormal based on an output of the first monitoring circuit; based on the determination result of the abnormality in the first lighting state, outputting the first enable signal, which controls whether or not to permit power supply to the second light-emitting diode in a second current supply path that supplies current to the second light-emitting diode of the second display device, to a second control terminal of the second power control element that controls power supply to the second light-emitting diode; The second display device is determining whether the second lighting state is abnormal based on an output of the second monitoring circuit; outputting the second enable signal, which controls whether or not to allow power supply to the first light-emitting diode in the first current supply path of the first display device, to the first control terminal of the first power control element based on the determination result of the abnormality in the second lighting state; A method for controlling a display system.

Images