Vehicle-mounted ceiling screen control circuit, vehicle-mounted control system and vehicle

Abstract

The utility model provides a vehicle-mounted ceiling screen control circuit, a vehicle-mounted control system and a vehicle, and is applied to the technical field of vehicles, the vehicle-mounted ceiling screen control circuit comprises a switch module, a delay reset module and an isolation module; a first input end of the delay reset module is connected with the switch module, a second input end of the delay reset module is connected with a reference voltage, an output end of the delay reset module is connected with the screen micro-control unit, and the delay reset module generates a first enable signal according to the voltage of the auxiliary power supply and the reference voltage; the first input end of the isolation module is connected with the output end of the delay reset module, the second input end of the isolation module is connected with the vehicle-mounted multimedia host, and the output end of the isolation module is connected with one end of the direct current converter. According to the vehicle-mounted ceiling screen control circuit, the on-state of the direct-current converter can be controlled through the dual enable signals and the isolation module, so that the standby power consumption of the whole vehicle is reduced when the vehicle-mounted ceiling screen does not need to be turned on.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and more specifically, to a vehicle-mounted ceiling screen control circuit, a vehicle-mounted control system and a vehicle in the vehicle field. Background Art

[0002] Vehicles are usually equipped with a ceiling screen to meet the needs of users in the car to a certain extent. At present, in order to control the switch state of the ceiling screen, the related technology usually uses an external button of the screen microcontroller unit (MCU) to monitor and control the ceiling screen. However, in this way, the screen microcontroller unit needs to keep the power on, and the standby power consumption is relatively high. Utility Model Content

[0003] The present application provides a vehicle-mounted ceiling screen control circuit, a vehicle-mounted control system and a vehicle. The vehicle-mounted ceiling screen control circuit can control the on-state of a DC converter through a dual enable signal and an isolation module, so as to reduce the standby power consumption of the entire vehicle when the vehicle-mounted ceiling screen does not need to be turned on.

[0004] In the first aspect, a vehicle-mounted ceiling screen control circuit is provided, which includes a switch module, a delay reset module and an isolation module, one end of the switch module is connected to an auxiliary power supply; a first input end of the delay reset module is connected to the other end of the switch module, a second input end of the delay reset module is used to access a reference voltage, an output end of the delay reset module is connected to a screen micro control unit, and the delay reset module is used to generate a first enable signal according to the voltage of the auxiliary power supply and the reference voltage; a first input end of the isolation module is connected to the output end of the delay reset module for accessing the first enable signal, a second input end of the isolation module is connected to the vehicle-mounted multimedia host for accessing the second enable signal, and the output end of the isolation module is connected to the enable end of the DC converter.

[0005] In the above technical scheme, the vehicle-mounted ceiling screen control circuit in this application realizes the switching of the high and low levels of the first enable signal by controlling the on and off of the switch module, so as to realize the control of the on state of the DC converter and the screen micro-control unit, and then realize the control of the vehicle-mounted ceiling screen switch, and the operation is simple. Among them, the control of the on state of the DC converter is realized by the dual enable signal (i.e., the first enable signal and the second enable signal) and the isolation module, that is, when the vehicle-mounted ceiling screen does not need to be turned on, the first enable signal and the second enable signal are both low levels to reduce the standby power consumption. When the vehicle-mounted ceiling screen needs to be turned on, the DC converter is first controlled to be turned on briefly by the first enable signal, and then the DC converter is kept in the on state by the second enable signal, so as to ensure the power supply reliability of the battery voltage of the vehicle-mounted battery to power the screen micro-control unit, and then ensure the stability of the vehicle-mounted ceiling screen. At the same time, the delayed reset module has the function of delayed reset, that is, after a certain period of time, the delayed reset module will reset the first enable signal to a low level. First, after the vehicle-mounted ceiling screen is turned on, it can prevent the first enable signal from always being at a high level, causing the screen microcontroller unit to be unable to turn off the vehicle-mounted display screen; second, after the vehicle-mounted ceiling screen is turned off, it can prevent the first enable signal from remaining at a high level, causing the DC converter to be mistakenly turned on, thereby increasing standby power consumption.

[0006] In combination with the first aspect, in some possible implementations, the delayed reset module includes a charge and discharge unit, a reference unit and a comparator; the first end of the charge and discharge unit is connected to the other end of the switch module, and the second end of the charge and discharge unit is grounded; the first end of the reference unit is connected to the auxiliary power supply, the second end of the reference unit is grounded, and the reference unit is used to generate a reference voltage; the non-inverting input end of the comparator is connected to the third end of the charge and discharge unit, the inverting input end of the comparator is connected to the third end of the reference unit, and the output end of the comparator is connected to the first input end of the isolation module and the screen micro control unit, for outputting a first enable signal.

[0007] In the above technical solution, the delay reset module can realize the automatic delay reset function through the comparator and the charge and discharge unit, without setting up an additional control circuit or adding an additional algorithm, thereby reducing the manufacturing cost.

[0008] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the switch module is disconnected, and the first enable signal and the second enable signal are both at low levels; the process of turning on the vehicle-mounted ceiling screen includes a first moment, a second moment and a third moment in sequence, the switch module is closed, at the first moment, the first enable signal is at a high level, and the second enable signal is at a low level, at the second moment, the second enable signal is at a high level, and at the third moment, the first enable signal is at a low level; wherein the time difference between the first moment and the third moment is greater than the time difference between the first moment and the second moment.

[0009] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the switch module is disconnected again, the first enable signal is at a low level, and the second enable signal is at a high level; the process of closing the vehicle-mounted ceiling screen includes a first moment, a third moment, and a fourth moment in sequence, the switch module is closed again, and at the fourth moment, the second enable signal is at a low level; wherein the time difference between the first moment and the third moment is less than the time difference between the first moment and the fourth moment.

[0010] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the reference unit includes a first resistor and a second resistor; one end of the first resistor is connected to the auxiliary power supply, and the other end of the first resistor is connected to the inverting input terminal of the comparator; one end of the second resistor is connected to the other end of the first resistor and the inverting input terminal of the comparator, and the other end of the second resistor is grounded.

[0011] In the above technical solution, the reference voltage can be changed by changing the resistance values ​​of the first resistor and the second resistor, thereby adjusting the delay time of the delay reset module.

[0012] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the charge and discharge unit includes a third resistor and a capacitor; one end of the third resistor is connected to the other end of the switch module, and the other end of the third resistor is connected to the non-inverting input terminal of the comparator; the first plate of the capacitor is connected to the other end of the switch module and one end of the third resistor, and the second plate of the capacitor is grounded.

[0013] In the above technical solution, the resistance value of the third resistor and / or the capacity of the capacitor can be changed to change the charging and discharging time of the charging and discharging unit, thereby adjusting the delay time of the delay reset module.

[0014] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the isolation module includes a first isolation unit and a second isolation unit; the input end of the first isolation unit is connected to the output end of the delay reset module for receiving the first enable signal, and the output end of the first isolation unit is connected to the enable end of the DC converter; the input end of the second isolation unit is connected to the vehicle-mounted multimedia host for receiving the second enable signal, and the output end of the second isolation unit is connected to the enable end of the DC converter.

[0015] In the above technical solution, the vehicle-mounted ceiling screen control circuit or the vehicle-mounted multimedia host can control the working state of the DC converter through the isolation module, that is, the dual enable signal can control the DC converter's on state.

[0016] In combination with the first aspect and the above implementations, in some possible implementations, the first isolation unit and the second isolation unit respectively include any one of a diode, a field effect transistor, or a relay switch.

[0017] In the second aspect, the present application provides a vehicle-mounted control system, comprising a DC converter, a vehicle-mounted multimedia host, a screen micro-control unit, and a vehicle-mounted ceiling screen control circuit as described in any optional manner of the first aspect, wherein the first end of the DC converter is used to access the battery voltage, the second end of the DC converter is connected to the first end of the screen micro-control unit, the second end of the screen micro-control unit is connected to the first end of the vehicle-mounted multimedia host, the second end of the vehicle-mounted multimedia host is connected to the second input end of the isolation module, the first output end of the vehicle-mounted ceiling screen control circuit is connected to the third end of the screen micro-control unit, and the second output end of the vehicle-mounted ceiling screen control circuit is connected to the enable end of the DC converter.

[0018] In a third aspect, the present application provides a vehicle, comprising a vehicle body and a vehicle-mounted control system as described in any optional manner of the second aspect, wherein the vehicle-mounted control system is mounted on the vehicle body. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the module structure of a vehicle-mounted control system provided by the related technology 1;

[0020] Figure 2 It is a schematic diagram of the module structure of a vehicle control system provided by the related technology 2;

[0021] Figure 3 It is a schematic diagram of a module structure of a vehicle-mounted control system provided in an embodiment of the present application;

[0022] Figure 4 It is a schematic diagram of the module structure of another vehicle-mounted control system provided in an embodiment of the present application;

[0023] Figure 5 It is a schematic diagram of the module structure of another vehicle-mounted control system provided in an embodiment of the present application;

[0024] Figure 6 is a line graph of signal changes provided by an embodiment of the present application;

[0025] Figure 7 is another line graph of signal changes provided in an embodiment of the present application;

[0026] Figure 8 It is a schematic diagram of the circuit structure of a vehicle-mounted control system provided in an embodiment of the present application.

[0027] Among them, the reference numerals in the figure are:

[0028] 1. On-board control system; 11. Switch circuit; 111. Switch controller; 12. Body domain controller; 13. On-board multimedia host; 14. Screen micro control unit; 15. Ceiling screen controller; 16. DC converter; 17. On-board battery; 18. On-board ceiling screen control circuit; 181. Switch module; 182. Delay reset module; 1821. Charge and discharge unit; 1822. Reference unit; 183. Isolation module; 1831. First isolation unit; 1832. Second isolation unit;

[0029] K1, first switch; K2, second switch; EN1, first enable signal; EN2, second enable signal; ACC, auxiliary power supply; VREF, reference voltage; VBAT, battery voltage; COMP, comparator; t1, first moment; t2, second moment; t3, third moment; t4, fourth moment; R1, first resistor; R2, second resistor; R3, third resistor; C, capacitor. DETAILED DESCRIPTION

[0030] The technical solution in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0031] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0032] Vehicles are usually equipped with a vehicle ceiling screen to meet the needs of users in the vehicle to a certain extent. In order to control the switch state of the vehicle ceiling screen, in the related art, an external independent switch is usually added, that is, a physical switch is added in the vehicle, and the switch state of the vehicle ceiling screen is controlled by pressing the switch.

[0033] Specifically, Figure 1As shown, the vehicle-mounted control system 1 in the vehicle provided by the related technology 1 includes a switching circuit 11, a body domain controller (Centra l E l ectron ic Module, CEM) 12, a vehicle multimedia host (Head Unit, HUT) 13, a screen micro control unit 14 and a ceiling screen controller 15 connected in sequence, wherein the switching circuit 11 includes a first switch K1 and a switch controller 111, one end of the first switch K1 is connected to the auxiliary power supply ACC, the other end of the first switch K1 is connected to one end of the switch controller 111, and the other end of the switch controller 111 is connected to the body domain controller 12. When the first switch K1 is pressed (i.e. closed), the body domain controller 12 is connected to the voltage provided by the auxiliary power supply ACC and sends a corresponding signal to the body domain controller 12, so that the body domain controller 12 can send a corresponding signal to the vehicle-mounted multimedia host 13 based on the signal, and the vehicle-mounted multimedia host 13 then sends a signal to the screen micro-control unit 14, so that the screen micro-control unit 14 sends a control signal to the ceiling screen controller 15, and the ceiling screen controller 15 controls the vehicle-mounted ceiling screen switch based on the control signal.

[0034] When the first switch K1 and the switch controller 111 are used to control the switch of the vehicle-mounted ceiling screen, the switch controller 111 usually needs to be connected to the body domain controller 12 through the serial communication protocol (Controller Area Network, CAN) or the serial communication network (Local Interconnect Network, LIN) to achieve signal transmission. However, the body domain controller 12 has limited ports, that is, the body domain controller 12 has limited ports for receiving signals from the CAN / LIN network. When the switch controller 111 needs to be connected to the body domain controller 12 through the CAN / LIN network, it will occupy the port of the body domain controller 12, that is, occupy the hard line resources of the body domain controller 12, resulting in other circuits using the CAN / LIN network being unable to achieve connection with the body domain controller 12, affecting the use of the entire vehicle.

[0035] In the related art 2, the screen micro control unit 14 is usually connected to a button, through which the vehicle ceiling screen is monitored and controlled. Figure 2As shown, the vehicle-mounted control system 1 in the vehicle includes a vehicle-mounted multimedia host 13, a screen micro-control unit 14, a DC converter 16 and a second switch K2. The second switch K2 is connected to the screen micro-control unit 14. When the second switch K2 is closed, the screen micro-control unit 14 will receive a switch signal. The screen micro-control unit 14 controls the switch of the vehicle-mounted ceiling screen based on the switch signal. At this time, since the switch signal is monitored by the screen micro-control unit 14, in order for the screen micro-control unit 14 to be able to monitor the switch signal of the second switch K2 in real time, the screen micro-control unit 14 needs to be in a working state at all times. In this way, after the vehicle is powered on, the screen micro-control unit 14 needs to maintain normal power, and the standby power consumption is relatively high.

[0036] At the same time, in order to make the screen micro control unit 14 always in working state, the vehicle multimedia host 13 needs to send an enable signal to the DC converter 16 which needs to be always high level. Here, it is worth explaining that one end of the DC converter 16 is connected to the vehicle battery 17, and the other end of the DC converter 16 is connected to the screen micro control unit 14. When the enable signal received by the DC converter 16 is high level, the vehicle battery 17 can supply power to the screen micro control unit 14, so that the screen micro control unit 14 is in working state. However, the other end of the DC converter 16 is usually also connected to other systems, such as a deserializer, a thin film transistor (TFT) display, a light emitting diode (LED) backlight system, etc. When the enable signal received by the DC converter 16 is high level, the screen micro control unit 14, the deserializer, the TFT display, and the LED backlight system connected thereto are all in working mode, thus further improving the standby power consumption.

[0037] To this end, an embodiment of the present application provides a vehicle-mounted ceiling screen control circuit, a vehicle-mounted control system and a vehicle. The vehicle-mounted ceiling screen control circuit can control the on state of the DC converter through a dual enable signal and an isolation module, so as to reduce the standby power consumption of the entire vehicle when the vehicle-mounted ceiling screen does not need to be turned on.

[0038] The following is an exemplary description of the vehicle-mounted ceiling screen control circuit, vehicle-mounted control system and vehicle provided in the embodiments of the present application in conjunction with the drawings.

[0039] The embodiment of the present application provides a vehicle, including a vehicle body and a vehicle-mounted control system, wherein the vehicle-mounted control system is mounted on the vehicle body, wherein Figure 3As shown, the vehicle control system 1 may include a DC converter 16, a vehicle multimedia host 13, a screen micro control unit 14, and a vehicle ceiling screen control circuit 18. The first end of the DC converter 16 is used to access the battery voltage VBAT, the second end of the DC converter 16 is connected to the first end of the screen micro control unit 14, the second end of the screen micro control unit 14 is connected to the first end of the vehicle multimedia host 13, the second end of the vehicle multimedia host 13 is connected to the first input end of the vehicle ceiling screen control circuit 18, the second input end of the vehicle ceiling screen control circuit 18 is connected to the auxiliary power supply ACC, the first output end of the vehicle ceiling screen control circuit 18 is connected to the third end of the screen micro control unit 14, and the second output end of the vehicle ceiling screen control circuit 18 is connected to the enable end of the DC converter 16.

[0040] Among them, the vehicle-mounted ceiling screen control circuit 18 outputs a first enable signal EN1 to the screen micro control unit 14 to control the switch of the vehicle-mounted ceiling screen. Specifically, when the vehicle-mounted ceiling screen needs to be turned on, the first enable signal EN1 output by the vehicle-mounted ceiling screen control circuit 18 to the screen micro control unit 14 is high. After receiving the first enable signal EN1, the screen micro control unit 14 completes the screen and deserialization initialization, and sends a start signal to the vehicle-mounted multimedia host 13. The vehicle-mounted multimedia host 13 can send a high-level second enable signal EN2 to the DC converter 16 through the vehicle-mounted ceiling screen control circuit 18 based on the start signal, so that the DC converter 16 is turned on, so that the battery voltage VBAT provided by the vehicle-mounted battery 17 can supply power to the screen micro control unit 14, thereby controlling the vehicle-mounted ceiling screen to be turned on.

[0041] Here, it is worth explaining that the enable end of the DC converter 16 not only receives the second enable signal EN2, but also receives the first enable signal EN1. In this way, when the vehicle-mounted multimedia host 13 does not receive the start signal, the second enable signal EN2 output by it is low, that is, the DC converter 16 is not turned on. At this time, when it is necessary to turn on the vehicle-mounted ceiling screen, so that the first enable signal EN1 output by the vehicle-mounted ceiling screen control circuit 18 is high, the first enable signal EN1 will cause the DC converter 16 to be turned on briefly, so that the vehicle-mounted battery 17 can supply power to the screen micro control unit 14, so that the screen micro control unit 14 can complete the screen and deserialization initialization, and send a start signal to the vehicle-mounted multimedia host 13, so that the second enable signal EN2 output by the vehicle-mounted multimedia host 13 is high, so that the DC converter 16 remains in the on state, ensuring the stability of the vehicle-mounted battery 17 supplying power to the screen micro control unit 14, thereby ensuring the control stability of the vehicle-mounted ceiling screen.

[0042] In this way, when the vehicle-mounted ceiling screen does not need to be turned on, the second enable signal EN2 output by the vehicle-mounted multimedia host 13 is at a low level, and the DC converter 16 is not turned on, that is, the screen micro-control unit 14 is not in a normal power state, which reduces the power consumption during standby and has better energy saving performance. Moreover, when the vehicle-mounted ceiling screen needs to be turned on, the vehicle-mounted ceiling screen control circuit 18 in the present application can send a high-level first enable signal EN1 to the flow converter 16 and the screen micro-control unit 14, so that the DC converter 16 is turned on briefly. At this time, the vehicle-mounted battery 17 can supply power to the screen micro-control unit 14, so that the screen micro-control unit 14 can complete the screen and deserialization initialization. At the same time, the screen micro-control unit 14 also receives the high-level first enable signal EN1, which will send a start signal to the vehicle-mounted multimedia host 13, so that the second enable signal EN2 output by the vehicle-mounted multimedia host 13 is converted to a high level, so that the DC converter 16 remains in the on state. In this way, the control of the on state of the DC converter 16 by dual enable signals (i.e., the first enable signal EN1 and the second enable signal EN2) is realized, which reduces the standby power consumption when the vehicle-mounted ceiling screen does not need to be turned on, and ensures the power supply reliability of the vehicle-mounted battery 17 to the screen micro control unit 14 when the vehicle-mounted ceiling screen needs to be turned on.

[0043] In one example, if Figure 4 As shown, the vehicle-mounted ceiling screen control circuit 18 provided in the embodiment of the present application may include a switch module 181, a delay reset module 182 and an isolation module 183. One end of the switch module 181 is connected to the auxiliary power supply ACC, the first input end of the delay reset module 182 is connected to the other end of the switch module 181, the second input end of the delay reset module 182 is used to access the reference voltage VREF, the output end of the delay reset module 182 is connected to the screen micro control unit 14, the first input end of the isolation module 183 is connected to the output end of the delay reset module 182, the second input end of the isolation module 183 is connected to the vehicle-mounted multimedia host 13, and the output end of the isolation module 183 is connected to the enable end of the DC converter 16.

[0044] Among them, the delay reset module 182 is used to generate a first enable signal EN1 according to the voltage of the auxiliary power supply ACC and the reference voltage VREF, the vehicle multimedia host 13 is used to provide a second enable signal EN2, and the isolation module 183 is used to receive the first enable signal EN1 and the second enable signal EN2, and control the start state of the DC converter 16 according to the first enable signal EN1 and the second enable signal EN2.

[0045] In this example, in the initial state, the switch module 181 is disconnected, the voltage received by the first input terminal of the delay reset module 182 is less than the reference voltage VREF received by the second input terminal thereof, the first enable signal EN1 is at a low level, and the second enable signal EN2 is also at a low level, and the DC converter 16 is not turned on.

[0046] When the vehicle-mounted ceiling screen needs to be turned on, the switch module 181 is closed, so that the voltage received by the first input terminal of the delay reset module 182 is greater than the reference voltage VREF received by its second input terminal, and the first enable signal EN1 is at a high level. At this time, the second enable signal EN2 still remains at a low level. The isolation module 183 turns on the DC converter 16 based on the high-level first enable signal EN1, so that the vehicle-mounted battery 17 can supply power to the screen micro-control unit 14, thereby enabling the screen micro-control unit 14 to complete the screen and deserialization initialization. At this time, the screen micro-control unit 14 will also receive the high-level first enable signal EN1, and then send an open signal to the vehicle-mounted multimedia host 13, so that the second enable signal EN2 output by the vehicle-mounted multimedia host 13 is converted to a high level, so that the DC converter 16 can remain in the open state to ensure the power supply reliability of the vehicle-mounted battery 17 to supply power to the screen micro-control unit 14, and at the same time enable the screen micro-control unit 14 to control the vehicle-mounted ceiling screen to turn on. When the vehicle-mounted ceiling screen remains in the on state, the second enable signal EN2 remains at a high level. At this time, the delay reset module 182 is set with a delay reset function, that is, the voltage received by the first input terminal of the delay reset module 182 will gradually decrease until it is less than the reference voltage VREF received by its second input terminal, so that the first enable signal EN1 output by the delay reset module 182 is reset to a low level. At this time, since the second enable signal EN2 remains at a high level, the screen micro control unit 14 can still control the vehicle-mounted ceiling screen to turn on.

[0047] When it is necessary to turn off the vehicle-mounted ceiling screen, the switch module 181 is closed again. At this time, the first enable signal EN1 output to the screen micro-control unit 14 is converted to a high level again. After the screen micro-control unit 14 detects that the first enable signal EN1 is at a high level, it controls the vehicle-mounted ceiling screen to turn off. At the same time, the screen micro-control unit 14 will also send a shutdown signal to the vehicle-mounted multimedia host 13, so that the second enable signal EN2 output by the vehicle-mounted multimedia host 13 is converted to a low level, so that the DC converter 16 is turned off to avoid generating additional standby power consumption. At this time, the delay reset module 182 still has a delay reset function, that is, after a certain period of time, the first enable signal EN1 output by the delay reset module 182 will be reset to a low level to avoid the first enable signal EN1 being maintained at a high level, causing the DC converter 16 to be mistakenly turned on, thereby causing the problem of increased standby power consumption.

[0048] In this way, the vehicle-mounted ceiling screen control circuit 18 provided in the present application realizes the switching of the high and low levels of the first enable signal EN1 by controlling the on and off of the switch module 181, so as to realize the control of the on state of the DC converter 16 and the screen micro control unit 14, and then realizes the control of the switch of the vehicle-mounted ceiling screen, and the operation is simple. Among them, the control of the on state of the DC converter 16 is realized by the dual enable signal (i.e., the first enable signal EN1 and the second enable signal EN2) and the isolation module 183, that is, when the vehicle-mounted ceiling screen is not needed to be turned on, the first enable signal EN1 and the second enable signal EN2 are both low levels to reduce the standby power consumption. When the vehicle-mounted ceiling screen needs to be turned on, the DC converter 16 is first controlled to be turned on briefly by the first enable signal EN1, and then the DC converter 16 is kept in the on state by the second enable signal EN2, so as to ensure the power supply reliability of the vehicle-mounted battery 17 to power the screen micro control unit 14, and then ensure the stability of the vehicle-mounted ceiling screen. At the same time, the delayed reset module 182 has the function of delayed reset, that is, after a certain period of time, the delayed reset module 182 will reset the first enable signal EN1 to a low level. First, after the vehicle-mounted ceiling screen is turned on, it can prevent the first enable signal EN1 from always being at a high level, causing the screen micro control unit 14 to be unable to turn off the vehicle-mounted display screen; second, after the vehicle-mounted ceiling screen is turned off, it can prevent the first enable signal EN1 from remaining at a high level, causing the DC converter 16 to be mistakenly turned on, thereby causing the problem of increased standby power consumption.

[0049] Optionally, the switch module 181 can be a physical button arranged near the screen micro control unit 14, so that it does not need to occupy the hard wire resources of the body domain controller 12, and at the same time, it is convenient for the operator to control.

[0050] In order to enable the delay reset module 182 to achieve automatic delay reset, in one example, Figure 5 As shown, the time-delay reset module 182 may include a charge-discharge unit 1821, a reference unit 1822, and a comparator COMP. The first end of the charge-discharge unit 1821 is connected to the other end of the switch module 181, the second end of the charge-discharge unit 1821 is grounded, the first end of the reference unit 1822 is connected to the auxiliary power supply ACC, the second end of the reference unit 1822 is grounded, the reference unit 1822 is used to generate a reference voltage VREF, and the in-phase input end (such as Figure 5 The inverting input terminal of the comparator COMP (as shown in FIG. Figure 5 The “-” shown in FIG. 1 is connected to the third end of the reference unit 1822 , and the output end of the comparator COMP is connected to the first input end of the isolation module 183 and the screen micro control unit 14 for outputting the first enable signal EN1 .

[0051] In this example, when the switch module 181 is disconnected, the voltage at the non-inverting input terminal of the comparator COMP is less than the reference voltage VREF at the inverting input terminal of the comparator COMP, and the first enable signal EN1 output by the comparator COMP is low level. When the switch module 181 is closed, the voltage provided by the auxiliary power supply ACC charges the charge and discharge unit 1821, so that the voltage at the non-inverting input terminal of the comparator COMP is greater than the reference voltage VREF at the inverting input terminal of the comparator COMP, and the first enable signal EN1 output by the comparator COMP is high level. After the voltage provided by the auxiliary power supply ACC charges the charge and discharge unit 1821 to a preset value, the charge and discharge unit 1821 discharges, and the voltage at the non-inverting input terminal of the comparator COMP slowly decreases until it is less than the reference voltage VREF at the inverting input terminal of the comparator COMP, and the first enable signal EN1 output by the comparator COMP is converted to a low level. In this way, the delay reset module 182 can realize the automatic delay reset function through the comparator COMP and the charge and discharge unit 1821, without setting an additional control circuit or adding an additional algorithm, thereby reducing the manufacturing cost.

[0052] Specifically, initially, the switch module 181 is disconnected, and the first enable signal EN1 and the second enable signal EN2 are both at a low level. When the vehicle ceiling screen needs to be turned on, the switch module 181 is closed. Figure 6 As shown, the process of turning on the vehicle ceiling screen includes the first moment t1, the second moment t2 and the third moment t3 in sequence. Here, it can be understood that the first moment t1, the second moment t2 and the third moment t3 refer to the moments when the high and low levels of the first enable signal EN1 and the second enable signal EN2 are converted after the switch module 181 is closed. Among them, at the first moment t1, the comparator COMP in-phase input terminal is charged, the first enable signal EN1 is at a high level, at this time, the second enable signal EN2 is still at a low level, and the comparator COMP sends the high-level first enable signal EN1 to the DC converter 16 and the screen micro control unit 14, so that the DC converter 16 is turned on and the screen micro control unit 14 outputs the start signal to the vehicle multimedia host 13. At the second moment t2, the vehicle multimedia host 13 receives the start signal, and the output second enable signal EN2 is at a high level, so that the DC converter 16 remains in the working state. At the third moment t3, the comparator COMP in-phase input terminal is discharged, and the first enable signal EN1 is converted to a low level. In this way, the control of opening the vehicle-mounted ceiling screen and the automatic delayed resetting of the delayed resetting module 182 are realized.

[0053] In order to avoid the problem that the delay time of the delay reset module 182 is too short, the first enable signal EN1 is reset to a low level when the second enable signal EN2 has not yet converted to a high level, so that the DC converter 16 is turned off, resulting in abnormal opening of the vehicle ceiling screen. Figure 6As shown, the time difference between the first moment t1 and the third moment t3 is greater than the time difference between the first moment t1 and the second moment t2, so that the first enable signal EN1 will be reset to a low level only after the screen micro control unit 14 completes the screen and deserialization initialization and sends a start signal to the vehicle multimedia host 13, so as to avoid the first enable signal EN1 and the second enable signal EN2 being both low levels, the DC converter 16 being turned off, and causing the vehicle ceiling screen to start abnormally.

[0054] When the vehicle ceiling screen is successfully turned on, the switch module 181 is turned off again, the first enable signal EN1 is at a low level, and the second enable signal EN2 is at a high level. When the vehicle ceiling screen needs to be turned off, the switch module 181 is closed again. Figure 7 As shown, the process of closing the vehicle ceiling screen includes the first moment t1, the third moment t3 and the fourth moment t4 in sequence. At the first moment t1, the in-phase input terminal of the comparator COMP is charged, and the first enable signal EN1 is at a high level. The comparator COMP sends the high-level first enable signal EN1 to the DC converter 16 and the screen micro-control unit 14. After the screen micro-control unit 14 detects that the first enable signal EN1 is at a high level again, the screen micro-control unit 14 closes the vehicle ceiling screen and sends a shutdown signal to the vehicle multimedia host 13. At the third moment t3, the in-phase input terminal of the comparator COMP is discharged, and the first enable signal EN1 is converted to a low level. At the fourth moment t4, the vehicle multimedia host 13 outputs a low-level second enable signal EN2 to close the DC converter 16, thereby avoiding the generation of additional standby power consumption, so that the standby power consumption of the vehicle control system 1 is less than 0.01W (watt), which is suitable for new energy vehicles that need to save energy and reduce consumption.

[0055] Here, it is worth mentioning that after the switch module 181 is closed again, since the charging and discharging time of the charging and discharging unit 1821 is constant, the voltage change at the non-inverting input terminal of the comparator COMP at this time is the same as the voltage change at the non-inverting input terminal of the comparator COMP in the above-mentioned process of turning on the vehicle-mounted ceiling screen, that is, the first moment t1 and the third moment t3 in the process of turning off the vehicle-mounted ceiling screen and the first moment t1 and the third moment t3 in the above-mentioned process of turning on the vehicle-mounted ceiling screen respectively refer to the same moments, that is, whether in the process of turning on the vehicle-mounted ceiling screen or in the process of turning off the vehicle-mounted ceiling screen, the high and low level conversion moment and conversion cycle of the first enable signal EN1 are the same.

[0056] Optionally, the comparator COMP may be any type of voltage comparator, and this application does not impose any specific limitation on this.

[0057] In order to avoid the problem that the vehicle multimedia host 13 converts the second enable signal EN2 to a low level after receiving the shutdown signal, causing the DC converter 16 to be shut down, thereby causing the vehicle ceiling screen to be shut down abnormally, such as Figure 7 As shown, the time difference between the first moment t1 and the third moment t3 is smaller than the time difference between the first moment t1 and the fourth moment t4, so as to ensure that the vehicle-mounted ceiling screen can be closed normally.

[0058] The delay time of the delay reset module 182 can be set according to actual needs, optionally, Figure 8 As shown, the reference unit 1822 may include a first resistor R1 and a second resistor R2, one end of the first resistor R1 is connected to the auxiliary power supply ACC, the other end of the first resistor R1 is connected to the inverting input terminal of the comparator COMP, one end of the second resistor R2 is connected to the other end of the first resistor R1 and the inverting input terminal of the comparator COMP, and the other end of the second resistor R2 is grounded. In this way, the resistance values ​​of the first resistor R1 and the second resistor R2 can be changed to change the size of the reference voltage VREF, thereby realizing the adjustment of the delay time of the delay reset module 182.

[0059] Optional, such as Figure 8 As shown, the charge and discharge unit 1821 may include a third resistor R3 and a capacitor C, one end R3 of the third resistor is connected to the other end of the switch module 181, the other end of the third resistor R3 is connected to the non-inverting input end of the comparator COMP, the first plate of the capacitor C is connected to the other end of the switch module 181 and one end of the third resistor R3, and the second plate of the capacitor C is grounded. In this way, the charge and discharge time of the charge and discharge unit 1821 can be changed by changing the resistance value of the third resistor R3 and / or the capacity of the capacitor C, thereby realizing the adjustment of the delay time of the delay reset module 182.

[0060] In order to realize the control of the on-state of the DC converter 16 by the dual enable signal, in one example, Figure 8As shown, the isolation module 183 may include a first isolation unit 1831 and a second isolation unit 1832, the input end of the first isolation unit 1831 is connected to the output end of the delay reset module 182 for accessing the first enable signal EN1, the output end of the first isolation unit 1831 is connected to the enable end of the DC converter 16, the input end of the second isolation unit 1832 is connected to the vehicle-mounted multimedia host 13 for accessing the second enable signal EN2, and the output end of the second isolation unit 1832 is connected to the enable end of the DC converter 16. In this way, when the first enable signal EN1 is at a high level and the second enable signal EN2 is at a low level, the vehicle-mounted ceiling screen control circuit 18 can realize the control of the working state of the DC converter 16, that is, the isolation module 183 sends the high-level first enable signal EN1 to the enable end of the DC converter 16; when the first enable signal EN1 is at a low level and the second enable signal EN2 is at a high level, the vehicle-mounted multimedia host 13 can realize the control of the working state of the DC converter 16, that is, the isolation module 183 sends the high-level second enable signal EN2 to the enable end of the DC converter 16. In this way, the vehicle-mounted ceiling screen control circuit 18 or the vehicle-mounted multimedia host 13 can realize the control of the working state of the DC converter 16 through the isolation module 183, that is, the control of the on-state of the DC converter 16 by the dual enable signals is realized.

[0061] Optionally, the first isolation unit 1831 and the second isolation unit 1832 may respectively include a diode, an N-type metal-oxide-semiconductor (N-Meta l-Oxi de-Semi conductor, NMOS), a P-type metal-oxide-semiconductor (P-Meta l-Oxi de-Semi conductor, PMOS), a relay switch, a transistor or other devices or circuits, to which the present application does not make any specific limitations.

[0062] In summary, the vehicle-mounted ceiling screen control circuit 18 provided in the present application realizes the switching of the high and low levels of the first enable signal EN1 by controlling the on and off of the switch module 181, so as to realize the control of the on state of the DC converter 16 and the screen micro control unit 14, and then realizes the control of the vehicle-mounted ceiling screen switch, and the operation is simple. Among them, the control of the on state of the DC converter 16 is realized by the dual enable signal (i.e., the first enable signal EN1 and the second enable signal EN2) and the isolation module 183, that is, when the vehicle-mounted ceiling screen is not needed to be turned on, the first enable signal EN1 and the second enable signal EN2 are both low levels to reduce the standby power consumption. When the vehicle-mounted ceiling screen needs to be turned on, the DC converter 16 is first controlled to be turned on briefly by the first enable signal EN1, and then the DC converter 16 is kept in the on state by the second enable signal EN2, so as to ensure the power supply reliability of the vehicle-mounted battery 17 to power the screen micro control unit 14, and then ensure the stability of the vehicle-mounted ceiling screen. At the same time, the delayed reset module 182 has the function of delayed reset, that is, after a certain period of time, the delayed reset module 182 will reset the first enable signal EN1 to a low level. First, after the vehicle-mounted ceiling screen is turned on, it can prevent the first enable signal EN1 from always being at a high level, causing the screen micro control unit 14 to be unable to turn off the vehicle-mounted display screen; second, after the vehicle-mounted ceiling screen is turned off, it can prevent the first enable signal EN1 from remaining at a high level, causing the DC converter 16 to be mistakenly turned on, thereby causing the problem of increased standby power consumption.

[0063] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0064] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0065] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A vehicle-mounted ceiling screen control circuit, applied to a vehicle, the vehicle comprising a DC converter, a screen micro-control unit and a vehicle-mounted multimedia host, the DC converter being connected to the screen micro-control unit and the vehicle-mounted multimedia host respectively, the screen micro-control unit being also connected to the vehicle-mounted multimedia host; characterized in that: The vehicle-mounted ceiling screen control circuit comprises: A switch module, one end of which is connected to an auxiliary power supply; A time-delay reset module, wherein a first input end of the time-delay reset module is connected to the other end of the switch module, a second input end of the time-delay reset module is used to access a reference voltage, an output end of the time-delay reset module is connected to the screen micro control unit, and the time-delay reset module is used to generate a first enable signal according to the voltage of the auxiliary power supply and the reference voltage; and An isolation module, wherein the first input end of the isolation module is connected to the output end of the delay reset module for receiving the first enable signal, the second input end of the isolation module is connected to the vehicle-mounted multimedia host for receiving the second enable signal, and the output end of the isolation module is connected to the enable end of the DC converter.

2. The vehicle-mounted ceiling screen control circuit according to claim 1, characterized in that: The time-delay reset module comprises: A charge and discharge unit, wherein a first end of the charge and discharge unit is connected to the other end of the switch module, and a second end of the charge and discharge unit is grounded; a reference unit, a first terminal of the reference unit being connected to the auxiliary power supply, a second terminal of the reference unit being grounded, and the reference unit being used to generate the reference voltage; and A comparator, wherein the non-inverting input terminal of the comparator is connected to the third terminal of the charge and discharge unit, the inverting input terminal of the comparator is connected to the third terminal of the reference unit, and the output terminal of the comparator is connected to the first input terminal of the isolation module and the screen micro control unit, for outputting the first enable signal.

3. The vehicle-mounted ceiling screen control circuit according to claim 2, characterized in that: The switch module is disconnected, and the first enable signal and the second enable signal are both at a low level; The process of turning on the vehicle ceiling screen includes a first moment, a second moment and a third moment in sequence, the switch module is closed, at the first moment, the first enable signal is a high level, the second enable signal is a low level, at the second moment, the second enable signal is a high level, at the third moment, the first enable signal is a low level; The time difference between the first moment and the third moment is greater than the time difference between the first moment and the second moment.

4. The vehicle-mounted ceiling screen control circuit according to claim 3, characterized in that: The switch module is disconnected again, the first enable signal is at a low level, and the second enable signal is at a high level; The process of closing the vehicle-mounted ceiling screen includes the first moment, the third moment and the fourth moment in sequence, the switch module is closed again, and at the fourth moment, the second enable signal is at a low level; The time difference between the first moment and the third moment is smaller than the time difference between the first moment and the fourth moment.

5. The vehicle-mounted ceiling screen control circuit according to claim 2, characterized in that: The reference unit comprises: a first resistor, one end of which is connected to the auxiliary power supply, and the other end of which is connected to the inverting input terminal of the comparator; and A second resistor, one end of the second resistor is connected to the other end of the first resistor and the inverting input end of the comparator, and the other end of the second resistor is grounded.

6. The vehicle-mounted ceiling screen control circuit according to claim 2, characterized in that: The charging and discharging unit comprises: A third resistor, one end of the third resistor is connected to the other end of the switch module, and the other end of the third resistor is connected to the non-inverting input end of the comparator; and A capacitor, wherein a first plate of the capacitor is connected to the other end of the switch module and one end of the third resistor, and a second plate of the capacitor is grounded.

7. The vehicle-mounted ceiling screen control circuit according to any one of claims 1 to 6, characterized in that: The isolation module comprises: a first isolation unit, wherein an input end of the first isolation unit is connected to an output end of the delay reset module and is used to receive the first enable signal, and an output end of the first isolation unit is connected to an enable end of the DC converter; and A second isolation unit, wherein the input end of the second isolation unit is connected to the vehicle-mounted multimedia host for receiving the second enable signal, and the output end of the second isolation unit is connected to the enable end of the DC converter.

8. The vehicle-mounted ceiling screen control circuit according to claim 7, characterized in that: The first isolation unit and the second isolation unit respectively include any one of a diode, a field effect transistor or a relay switch.

9. A vehicle-mounted control system, characterized in that: The vehicle-mounted control system comprises a DC converter, a vehicle-mounted multimedia host, a screen micro-control unit and a vehicle-mounted ceiling screen control circuit as described in any one of claims 1 to 8; The first end of the DC converter is used to access the battery voltage, the second end of the DC converter is connected to the first end of the screen micro control unit, the second end of the screen micro control unit is connected to the first end of the vehicle-mounted multimedia host, the second end of the vehicle-mounted multimedia host is connected to the second input end of the isolation module, the first output end of the vehicle-mounted ceiling screen control circuit is connected to the third end of the screen micro control unit, and the second output end of the vehicle-mounted ceiling screen control circuit is connected to the enable end of the DC converter.

10. A vehicle, characterized in that: The vehicle includes a vehicle body and the vehicle-mounted control system according to claim 9, wherein the vehicle-mounted control system is mounted on the vehicle body.

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