Power supply circuit of automotive electronic equipment

Abstract

The embodiment of the utility model provides a power supply circuit of an automobile electronic device, and the circuit comprises a standby power interface which is electrically connected with a standby power supply; the main power interface is electrically connected with a main power supply; the power utilization end interface is electrically connected with a power utilization end; the charging circuit is electrically connected between the main power supply interface and the standby power supply interface; the output switching circuit is electrically connected with the main power supply interface, the standby power supply interface and the power utilization end interface; when the output switching circuit detects that the main power supply interface is connected with the main power supply, the output switching circuit supplies power to the power utilization end through the main power supply. When it is not detected that the main power supply interface is connected with the main power supply, the standby power supply supplies power to the power utilization end; and the charging circuit is used for charging the standby power supply through the main power supply. According to the technical scheme of the embodiment of the invention, seamless switching can be realized, the equipment reliability is improved, the user perception is reduced, the standby power supply is automatically charged, and the manpower and time cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of automotive electronic equipment, and in particular to a power supply circuit of automotive electronic equipment. Background Art

[0002] In recent years, with the increase in people's demands for driving, information, entertainment, safety and other aspects, the integration and modularization of automobiles have become increasingly higher. This has brought new challenges to the research and development of vehicle systems, among which power supply design is the first to bear the brunt. Since the car cannot provide power for automotive electronic equipment when the engine is turned off, it brings great inconvenience to users. It should be noted that the above content is not necessarily prior art, nor is it used to limit the scope of patent protection of this application. Utility Model Content

[0003] The embodiments of the present application provide a power supply circuit for an automotive electronic device to solve or alleviate one or more of the technical problems mentioned above.

[0004] As one aspect of an embodiment of the present application, an embodiment of the present application provides a power supply circuit of an automotive electronic device, including:

[0005] A backup power supply interface, used for electrically connecting a backup power supply;

[0006] A main power interface, used for electrically connecting to a main power source;

[0007] A power-using end interface, used for electrically connecting to a power-using end;

[0008] A charging circuit, electrically connected between the main power interface and the backup power interface;

[0009] An output switching circuit electrically connecting the main power interface, the backup power interface and the power consumption end interface;

[0010] Among them, when the output switching circuit detects that the main power interface is connected to the main power supply, the output switching circuit supplies power to the power-consuming end through the main power supply; when the main power interface is not detected to be connected to the main power supply, the output switching circuit supplies power to the power-consuming end through the backup power supply; the charging circuit is used to charge the backup power supply through the main power supply.

[0011] Optionally, the buck-boost circuit comprises an input end, an output end, and a control end, wherein the input end is used to electrically connect to the main power interface, and the output end is used to electrically connect to the backup power interface;

[0012] A controller, used for electrically connecting the input end, the output end and the control end of the buck-boost circuit;

[0013] A reference circuit, comprising an input end and an output end, wherein the input end is used to electrically connect the main power interface and the backup power interface, and the output end is used to electrically connect the buck-boost circuit and the controller, and is used to provide a reference voltage for the buck-boost circuit and the controller;

[0014] The control end generates a control signal according to the input and output ends of the buck-boost circuit, and inputs the control signal into the control end of the buck-boost circuit, thereby controlling and adjusting the voltage and / or current of the buck-boost circuit.

[0015] Optionally, the controller is further configured to be electrically connected to the output switching circuit;

[0016] Correspondingly, the power supply circuit also includes: a detection circuit, used to electrically connect to the controller, used to electrically connect to the output end of the output switching circuit to detect output current / voltage information, and output the detected output current / voltage information to the controller so that the controller controls the on and off of the output switching circuit.

[0017] Optionally, a switch interface for electrically connecting a switch;

[0018] The controller is also used to electrically connect the switch interface;

[0019] The switch is toggled to enable the controller to control the on and off of the output switching circuit.

[0020] Optionally, the controller is also used to electrically connect the program burning port;

[0021] The program burning port is used to load the program and / or firmware into the controller to implement programming, debugging and firmware updating of the power supply circuit.

[0022] The embodiments of the present application using the above technical solution may include the following advantages: a main power supply and a backup power supply are provided. When the main power supply fails or is interrupted, the output switching circuit can seamlessly switch to the backup power supply to ensure continuous power supply of the equipment, avoid single-point failure problems of a single failure point, reduce the risk of equipment downtime, improve equipment reliability, reduce users' perception of power outages, and avoid impacts on user experience and operations. In addition, charging the backup power supply through the main power supply can improve the reliability of the backup power supply, ensure that the backup power supply can be quickly switched to and provide continuous power supply when the main power supply fails, and the main power supply can charge the backup power supply automatically without manual intervention, so that the backup power supply is in good condition, reducing manpower and time costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.

[0024] Figure 1 It is a circuit connection diagram of the power supply circuit provided in an embodiment of the present application.

[0025] Figure 2 It is a circuit connection diagram of the buck-boost circuit provided in an embodiment of the present application.

[0026] Figure 3 It is a circuit connection diagram of an output switching circuit, a detection circuit, a controller, etc. provided in an embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other in the absence of conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] The following provides an explanation of the terms used in this application.

[0030] Reference Circuit: A circuit used in electronic design to provide a stable, reliable reference signal or reference voltage. It is often used to calibrate, compare and measure the performance of other circuits and as a benchmark for other circuits in the design.

[0031] Boost-Buck Circuit: An electronic circuit used to step up or step down the voltage of the input power supply to provide the required output voltage.

[0032] To facilitate those skilled in the art to understand the technical solutions provided in the embodiments of the present application, the relevant technologies are described below:

[0033] Buck-boost circuit charging technology: a power conversion technology that can convert low voltage into high voltage or high voltage into low voltage to meet the charging needs of different electronic devices.

[0034] To this end, the present application provides a power supply circuit technology solution for automotive electronic equipment. The solution is briefly described as follows:

[0035] The converter U1 / U3 (ML45B0016) is combined with the controller U2 (ML8F3216) to form a buck-boost module circuit to achieve constant voltage and constant current charging for the battery. The backup power interface J1 (connected to 12.8V / 4 series lithium iron phosphate batteries), the main power interface J2 (supports 10-15V input), when there is input access, a constant 5V (%1) reference voltage is provided to the converter U1, the controller U2, and the converter U3 through the linear regulator U6 (CXM7550-2), and the NMOS tube Q5 (the input voltage detection pin of the controller U2 is set high by default) is pulled low to wake up the controller U2, and the DC charger enable control pin of the controller U2 is set high, and the PMOS tube Q1 (GTMQ4407A) is controlled to be turned on through the NMOS tube Q4, the resistor R1, the resistor R15, and the resistor R16, and the input voltage is detected by the resistor R10 and the resistor R11 through the input voltage pin of the controller U2, and the battery voltage is detected by the resistor R4, the NMOS tube Q2, and the resistor R5 through the battery voltage pin of the controller U2. The battery temperature is detected by resistor R24, thermistor NTC, and the thermistor pin of controller U2. The input current is detected by resistor R18, resistor R21, diode-based regulator U5, and the charging current pin of controller U2. Then, synchronous buck-boost is realized through controller U2 pulse width modulation signal 0 pin, controller U2 pulse width modulation signal 1 pin, controller U2 driver enable control 1 pin, and controller U2 driver enable control pin (control converter U1 / U3 (ML45B0016) to charge the backup power battery.

[0036] When the device is connected, the output is turned on (normally open state, there is no discharge over-temperature, over-current protection, converter U2 enters sleep mode, self-power consumption is less than 100uA), when the current amplifier U4 (HTC6233), resistor R28 detects that the output current is greater than 0.5A, the controller U2 is awakened through the output B pin of the current amplifier U4. At this time, when the output over-voltage, over-temperature, and over-current are detected, the output voltage enable control pin of the controller U2 is used to control the NMOS tube Q3 (GTM2321L) to turn off the output. If it needs to be released, the switch SW1 must be toggled.

[0037] The backup power supply principle of portable automotive electronic equipment (LCD TV): When the main power interface J2 is connected (the car battery is turned on), the power is directly output to the LCD TV through diodes D4 and D5 (SS54); when no device is connected to the main power interface J2 (the car battery is not turned on), the power is output to the automotive electronic equipment (LCD TV) through diodes D2 and D3 (SS54), thereby achieving seamless connection.

[0038] Hereinafter, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. It should be noted that these exemplary embodiments can be implemented in many different forms and should not be construed as being limited to the embodiments described herein.

[0039] like Figures 1 to 3 As shown, the power supply circuit may include: a backup power supply interface, a main power supply interface, a power consumption end interface, a charging circuit, and an output switching circuit.

[0040] The backup power supply interface is used to electrically connect the backup power supply.

[0041] Main power interface, used for electrically connecting to the main power supply.

[0042] The power consumption end interface is used for electrically connecting to the power consumption end.

[0043] The charging circuit is electrically connected between the main power interface and the backup power interface.

[0044] The output switching circuit is electrically connected to the main power interface, the backup power interface and the power consumption end interface.

[0045] Among them, when the output switching circuit detects that the main power interface is connected to the main power supply, the output switching circuit supplies power to the power-consuming end through the main power supply; when the main power interface is not detected to be connected to the main power supply, the output switching circuit supplies power to the power-consuming end through the backup power supply; the charging circuit is used to charge the backup power supply through the main power supply.

[0046] In the above embodiment, when the main power interface J2 and the backup power interface J1 are connected, the main power is charged to the backup power through the charging circuit. In addition, when the main power interface J2 is connected (the car battery is turned on), the main power is directly output to the car electronic device (LCD TV); when the main power interface J2 is not connected (the car battery is not turned on), the backup power is used to power the car electronic device (LCD TV), thereby achieving seamless connection.

[0047] In an optional embodiment, the output switching circuit includes a diode D2, a diode D3, a diode D4, a diode D5, a resistor R26, a resistor R28, a resistor R29, a resistor R30, an NMOS tube Q3, and a capacitor C27. Among them, the backup power interface J1 is connected to the positive electrodes of the diodes D2 and D3, the main power interface J2 is connected to the positive electrodes of the diodes D4 and D5, and the negative electrodes of the diodes D2, D3, D4, and D5 are connected to the power-using end interface J4 through the resistor R26 for voltage division. The power-using end interface J4 is also connected to the drain of the NMOS tube Q3, the source of the NMOS tube Q3 is connected to the gate of the NMOS tube Q3 through the resistor R29, one way is connected in series with the resistor R30 and the capacitor C27 to the digital ground, and one way is connected to the analog ground through the resistor R28; the output voltage enable control pin of the controller U2 is connected to the gate of the NMOS tube Q3, and the output current pin of the controller U2 is connected to the end of the capacitor C27 that is not connected to the digital ground.

[0048] In the above optional embodiment, when the main power interface J2 has input access (the car battery is turned on), the electronic device (LCD TV) is directly powered by diodes D4 and D5 (SS54); when the main power interface J2 has no device connected (the car battery is not turned on), the car electronic device (LCD TV) is powered by diodes D2 and D3 (SS54), thereby achieving seamless connection. In addition, when output overvoltage, overtemperature, and overcurrent are detected, the output voltage enable control pin of the controller U2 is used to control the NMOS tube Q3 (GTM2321L) to turn off the output.

[0049] Therefore, through the output switching circuit of this embodiment, while ensuring continuous power supply to the device, the reliability of the device is improved and the impact on user experience and operation is avoided.

[0050] In an optional embodiment, the charging circuit includes: a buck-boost circuit, a controller, and a reference circuit.

[0051] The buck-boost circuit comprises an input end, an output end and a control end. The input end is used to electrically connect to a main power interface, and the output end is used to electrically connect to a backup power interface.

[0052] The controller is used to electrically connect the input end, the output end and the control end of the buck-boost circuit.

[0053] The reference circuit includes an input end and an output end. The input end is used to electrically connect the main power interface and the backup power interface. The output end is used to electrically connect the buck-boost circuit and the controller to provide a reference voltage for the buck-boost circuit and the controller.

[0054] The control end generates a control signal according to the input and output ends of the buck-boost circuit, and inputs the control signal into the control end of the buck-boost circuit, thereby controlling and adjusting the voltage and / or current of the buck-boost circuit.

[0055] In the above optional embodiment, a constant 5V (% 1) reference voltage is provided to the buck-boost circuit and the controller through a reference circuit, and the controller controls the buck-boost circuit to realize synchronous buck-boost to charge the backup power supply.

[0056] It can be seen that by charging the backup power supply from the main power supply through the buck-boost circuit and the reference circuit of this embodiment, a stable charging voltage can be provided, thereby ensuring that the charging voltage is within an appropriate range, avoiding damage to the battery, improving the charging efficiency and charging speed, and at the same time being able to improve the reliability of the backup power supply, ensuring that when the main power supply fails, it can quickly switch to the backup power supply and provide continuous power supply. The main power supply can charge the backup power supply automatically without manual intervention, so that the backup power supply is in good condition, reducing manpower and time costs.

[0057] In an optional embodiment, the buck-boost circuit includes: a converter U1 and a converter U3, and the converter U1 and the converter U3 are both electrically connected to the controller U2.

[0058] The buck-boost circuit also includes: a PMOS tube Q1, an NMOS tube Q2, an NMOS tube Q4, an NMOS tube Q5, a converter U1, a converter U3, a diode-based regulator U5, an inductor L1, a resistor R1, a resistor R2, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a resistor R15, a resistor R16, a resistor R17, a resistor R18, a resistor R21, a capacitor C1, a capacitor (C2), a capacitor C3, a capacitor C4, a capacitor C5, a capacitor C6, a capacitor C7, a capacitor C8, a capacitor C9, a capacitor C11, a capacitor C12, a capacitor C13, a capacitor C14, a capacitor C15, a capacitor C16, a capacitor C17, a capacitor C18, a capacitor C19, an electrolytic capacitor EC1, and an electrolytic capacitor EC2.

[0059] Among them, the negative pin of the backup power interface J1 is connected to the analog ground.

[0060] The positive pin of the backup power supply interface J1 is connected in parallel to capacitor C1, capacitor C2, capacitor C3, capacitor C4, and electrolytic capacitor EC1 to the analog ground; one pin is connected in series to resistor R4 and the drain of field effect transistor Q2, the gate of field effect transistor Q2 is connected to the sleep mode enable control pin of controller U2, the source of field effect transistor Q2 is connected to resistor R5 to the analog ground, one pin is connected to capacitor C15 to the digital ground, one pin is connected to the battery voltage pin of controller U2; one pin is connected to capacitor C5 to the analog ground; one pin is connected to the input power pin and the boost pin of converter U1 respectively.

[0061] The pulse width modulation pin of the converter U1 is connected to the pulse modulation signal 0 pin of the controller U2, the serial mode selection pin and the enable pin of the converter U1 are connected to the driver enable control pin of the controller U2, the overcurrent protection pin of the converter U1 is connected to the resistor R6 and connected to the analog ground, and the ground pin and the power ground pin of the converter U1 are connected to the analog ground.

[0062] The positive pole of the main power interface J2 is connected to the capacitor C14 and connected to the analog ground; one is connected in series with the resistor R2 and the gate of the field effect tube Q5, the gate of the field effect tube Q5 is also connected to the resistor R17 and connected to the digital ground, the drain of the field effect tube Q5 is connected to the input voltage detection pin of the controller U2, and the source of the field effect tube Q5 is connected to the digital ground; one is connected to the resistor R1 through the drain and source of the field effect tube Q1, the other end of the resistor R1 is connected to the gate of the field effect tube Q1, and one is connected in series with the resistor R15 and the drain of the field effect tube Q4. The source of tube Q4 is connected to analog ground, the gate of field effect tube Q4 is connected to resistor R16 connected to analog ground, and the gate of field effect tube Q4 is also connected to the DC charger enable control pin of controller U2; one way is connected in series with resistor R11 and resistor R10 connected to analog ground, the ungrounded end of resistor R10 is connected to the input voltage pin of controller U2, one way is connected to capacitor C18 connected to digital ground; one way is connected in parallel with capacitor C11, capacitor C12, capacitor C13, and electrolytic capacitor EC2 connected to analog ground; one way is connected to the input power pin of converter U3.

[0063] The negative pin of the main power interface J2 is connected to the analog ground through resistor R18, and is connected to the analog ground through capacitor C19 through a diode-based regulator U5. The cathode pin of the diode-based regulator U5 is connected to the output battery enable control pin of the controller U2 through a resistor R21 voltage divider, and the cathode pin of the diode-based regulator and the reference voltage output pin are connected to the charging current pin of the controller U2.

[0064] The pulse width modulation pin of the converter U3 is connected to the pulse modulation signal 1 pin of the controller U2, the serial mode selection pin and the enable pin of the converter U3 are connected to the driver enable control 1 pin of the controller U2, the overcurrent protection pin of the converter U3 is connected to the resistor R9 and connected to the analog ground, and the ground pin and the power ground pin of the converter U3 are connected to the analog ground.

[0065] The inductor switch pin of converter U1 is connected to the inductor switch pin of converter U3 through inductor L1, the boost pin of converter U1 and the inductor switch pin are connected through capacitor C17, the boost pin of converter U3 and the inductor switch pin are connected through capacitor C8, and the two ends of inductor L1 are connected in series with capacitor C6, capacitor C7, resistor R7, and resistor R8 to analog ground.

[0066] The reference circuit includes capacitor C24, capacitor C25, capacitor C26, resistor R25, linear regulator (U6), diode D1, diode D6, and voltage regulator diode Z. Among them, the backup power interface J1 is connected to the positive electrode of diode D6, the main power interface J2 is connected to the positive electrode of diode D1, the cathode of diode D6 and diode D1 are connected to the input voltage pin of linear regulator U6 through resistor R25, the input voltage pin of linear regulator U6 is also connected to the negative power supply pin of linear regulator U6 through capacitor C26 and connected to digital ground, the output voltage pin of linear regulator U6 is connected to the negative power supply pin of linear regulator U6 through parallel voltage regulator diode Z1, capacitor C25 and capacitor C26, the output voltage pin of linear regulator U6 is also connected to the positive power supply voltage pin and dedicated positive power supply voltage pin of converter U1 and converter U3, and the output voltage pin of linear regulator U6 is also connected to the positive power supply voltage pin of controller U2.

[0067] The power supply circuit also includes: a capacitor C10 and a capacitor C22.

[0068] Correspondingly, the positive power supply voltage pin of the controller U2 is connected to the ground pin 20 of the controller U2 via the capacitor C10 and connected to the digital ground, and the charging current pin of the controller U2 is connected to the digital ground via the capacitor C22.

[0069] In the above optional embodiments, a constant 5V (%1) reference voltage is provided to the converter U1, the controller U2, and the converter U3 through the linear regulator U6 (CXM7550-2), and the NMOS tube Q5 (the input voltage detection pin of the controller U2 is set to high by default) is pulled low to wake up the controller U2, and the DC charger enable control pin of the controller U2 is set high, and the PMOS tube Q1 (GTMQ4407A) is turned on through the NMOS tube Q4, the resistor R1, the resistor R15, and the resistor R16, and the input voltage is detected by the resistor R10 and the resistor R11 through the input voltage pin of the controller U2, and the battery voltage is detected by the resistor R4, the NMOS tube Q2, and the resistor R5 through the battery voltage pin of the controller U2. The battery temperature is detected by resistor R24, thermistor NTC, and the thermistor pin of controller U2. The input current is detected by resistor R18, resistor R21, diode-based regulator U5, and the charging current pin of controller U2. Then, synchronous buck-boost is realized through controller U2 pulse width modulation signal 0 pin, controller U2 pulse width modulation signal 1 pin, controller U2 driver enable control 1 pin, and controller U2 driver enable control pin (control converter U1 / U3 (ML45B0016) to charge the backup power battery.

[0070] In an optional embodiment, the controller is also used to electrically connect the output switching circuit.

[0071] Correspondingly, the power supply circuit further includes a detection circuit which is electrically connected to the controller and is used to electrically connect to the output end of the output switching circuit to detect output current / voltage information, and output the detected output current / voltage information to the controller so that the controller controls the on / off of the output switching circuit.

[0072] It can be seen that the detection circuit of this embodiment can monitor voltage, current, and temperature in real time and take corresponding measures to make adjustments in time when abnormal conditions are found, so as to ensure the normal operation and optimal performance of the equipment.

[0073] In an optional embodiment, the detection circuit includes: a current operational amplifier detection circuit, an output voltage detection circuit, and an NTC temperature detection circuit.

[0074] The current operational amplifier detection circuit is used to detect the output current, to wake up the controller U2 and / or to feed back the output current information to the controller U2.

[0075] The output voltage detection circuit is used to detect the output voltage and to feed back the output voltage information to the controller U2.

[0076] The NTC temperature detection circuit is used to detect the temperature and to feed back the temperature information to the controller U2.

[0077] The circuit operational amplifier detection circuit includes: a current operational amplifier U4, a capacitor C20, a resistor R12, a resistor R13, a resistor R14, a resistor R19, a resistor R20, and a resistor R27. The positive power supply pin of the current amplifier U4 is connected to a 5V positive voltage, and is connected to the negative power supply pin of the current amplifier U4 through capacitor C20 to the analog ground. The positive pin of the input A of the current amplifier U4 is connected to the output end of the output switching circuit through resistor R24. The output A pin of the current amplifier U4 is connected to the negative pin of the input B of the current amplifier U4, and is connected to the negative pin of the input A of the current amplifier U4 through a voltage divider of resistor R13. The negative pin of the input A of the current amplifier U4 is also connected to resistor R12 to the analog ground. The output B pin of the current amplifier U4 is connected to the load detection pin of the controller U2, and is connected to the positive pin of the input B of the current amplifier U4 through series resistors R19 and R20. The positive pin of the input B of the current amplifier U4 is also connected to resistor R27 to the analog ground.

[0078] The output voltage detection circuit includes: capacitor C21, resistor R23, and resistor R22. The output voltage pin of the controller U2 is connected to the output end of the output switching circuit through resistor R22, and connected to the digital ground through capacitor C21 and resistor R23 in parallel.

[0079] The NTC temperature detection circuit includes: a resistor R24, a capacitor C23, and a thermistor NTC. The sleep mode enable control pin of the controller U2 is connected to the thermistor pin of the controller U2 through the resistor R24, and the thermistor pin of the controller U2 is also connected in parallel with the thermistor NTC and the capacitor C23 to the digital ground.

[0080] In the above optional embodiment, when the device is connected, the output is turned on (normally open state, there is no discharge overtemperature, overcurrent protection, converter U2 enters sleep mode, and self-power consumption is less than 100uA), when the current amplifier U4 (HTC6233), resistor R28 detects that the output current is greater than 0.5A, the controller U2 is awakened through the output B pin of the current amplifier U4.

[0081] In an optional embodiment, the switch interface is used to electrically connect the switch.

[0082] The controller is also used to electrically connect the switch interface.

[0083] The switch is toggled to enable the controller to control the on and off of the output switching circuit.

[0084] It can be seen that the output on-off function is realized by the physical contact method of this embodiment, and the structure is simple and reliable.

[0085] In an optional embodiment, the switch interface is used to electrically connect the switch SW1, and pin 1 of the switch interface is connected to a positive voltage of 5V; pin 2 of the switch interface is connected to the sleep mode enable control pin of the controller U2, and is connected to the analog ground through the resistor R3.

[0086] In the above optional embodiment, if it is necessary to release the shutdown output due to overvoltage, overcurrent, or overtemperature, the switch SW1 must be toggled.

[0087] In an optional embodiment, the controller is also used to electrically connect the program burning port.

[0088] The program burning port is used to load the program and / or firmware into the controller to implement programming, debugging and firmware updating of the power supply circuit.

[0089] It can be seen that the functionality, reliability and user experience of the electronic device can be improved through the program burning port of this embodiment.

[0090] In an optional embodiment, the positive power supply voltage pin of the program burning port J3 is connected to a 5V positive voltage, the PA2 pin of the program burning port J3 is connected to the data transmission signal pin of the controller U2, the PA0 pin of the program burning port J3 is connected to the sleep mode enable control pin of the controller U2, and the ground pin of the program burning port J3 is connected to the digital ground.

[0091] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0092] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0093] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0094] It should also be noted that "one embodiment", "another embodiment", "embodiment", etc. mentioned in this specification refer to the specific features, structures or characteristics described in conjunction with the embodiment included in at least one embodiment generally described in this application. The same expression appearing in multiple places in the specification does not necessarily refer to the same embodiment. Further, when a specific feature, structure or characteristic is described in conjunction with any embodiment, it is claimed that the realization of such feature, structure or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0095] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0096] It should also be noted that the above are only preferred embodiments of the present application, and the patent protection scope of the present application is not limited thereto. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A power supply circuit for automotive electronic equipment, characterized in that: include: A backup power supply interface, used for electrically connecting a backup power supply; A main power interface, used for electrically connecting to a main power source; A power-using end interface, used for electrically connecting to a power-using end; A charging circuit, electrically connected between the main power interface and the backup power interface; An output switching circuit electrically connecting the main power interface, the backup power interface and the power consumption end interface; Among them, when the output switching circuit detects that the main power interface is connected to the main power supply, the output switching circuit supplies power to the power-consuming end through the main power supply; when the main power interface is not detected to be connected to the main power supply, the output switching circuit supplies power to the power-consuming end through the backup power supply; the charging circuit is used to charge the backup power supply through the main power supply.

2. The power supply circuit of the automotive electronic equipment according to claim 1, characterized in that: The charging circuit comprises: The buck-boost circuit comprises an input terminal, an output terminal and a control terminal, wherein the input terminal is used to electrically connect to a main power supply interface, and the output terminal is used to electrically connect to a backup power supply interface; A controller, used for electrically connecting the input end, the output end and the control end of the buck-boost circuit; A reference circuit, comprising an input end and an output end, wherein the input end is used to electrically connect the main power interface and the backup power interface, and the output end is used to electrically connect the buck-boost circuit and the controller, and is used to provide a reference voltage for the buck-boost circuit and the controller; The control end generates a control signal according to the input and output ends of the buck-boost circuit, and inputs the control signal into the control end of the buck-boost circuit, thereby controlling and adjusting the voltage and / or current of the buck-boost circuit.

3. The power supply circuit of the automotive electronic equipment according to claim 1, characterized in that: The controller is also used to electrically connect the output switching circuit; Correspondingly, the power supply circuit also includes: a detection circuit; the detection circuit is electrically connected to the controller, used to electrically connect to the output end of the output switching circuit to detect output current / voltage information, and output the detected output current / voltage information to the controller, so that the controller controls the on and off of the output switching circuit.

4. The power supply circuit of the automotive electronic equipment according to claim 3, characterized in that: A switch interface, used for electrically connecting a switch; The controller is also used to electrically connect the switch interface; The switch is toggled to enable the controller to control the on and off of the output switching circuit.

5. The power supply circuit of the automotive electronic equipment according to claim 1, characterized in that: The controller is also used to electrically connect the program burning port; The program burning port is used to load the program and / or firmware into the controller to implement programming, debugging and firmware updating of the power supply circuit.

6. The power supply circuit of the automotive electronic equipment according to claim 1, characterized in that: The output switching circuit includes: a diode D2, a diode D3, a diode D4, a diode D5, a resistor R26, a resistor R28, a resistor R29, a resistor R30, an NMOS tube Q3, and a capacitor C27; Among them, the backup power supply interface J1 is connected to the positive electrodes of the diodes D2 and D3, the main power supply interface J2 is connected to the positive electrodes of the diodes D4 and D5, and the cathodes of the diodes D2, D3, D4 and D5 are connected to the power-using end interface J4 through the resistor R26 for voltage division; the power-using end interface J4 is also connected to the drain of the NMOS tube Q3, the source of the NMOS tube Q3 is connected to the gate of the NMOS tube Q3 through the resistor R29, one way is connected in series with the resistor R30 and the capacitor C27 to the digital ground, and one way is connected to the analog ground through the resistor R28; the output voltage enable control pin of the controller U2 is connected to the gate of the NMOS tube Q3, and the output current pin of the controller U2 is connected to the end of the capacitor C27 that is not connected to the digital ground.

7. The power supply circuit of the automotive electronic equipment according to claim 2, characterized in that: The buck-boost circuit includes: a converter U1 and a converter U3, and the converter U1 and the converter U3 are both electrically connected to a controller U2.

8. The power supply circuit of the automotive electronic equipment according to claim 3, characterized in that: The detection circuit comprises: A current operational amplifier detection circuit, used for detecting the output current, for waking up the controller U2 and / or feeding back the output current information to the controller U2; An output voltage detection circuit, used to detect the output voltage and to feed back the output voltage information to the controller U2; The NTC temperature detection circuit is used to detect the temperature and to feed back the temperature information to the controller U2.

9. The power supply circuit of the automotive electronic equipment according to claim 4, characterized in that: Pin 1 of the switch interface is connected to a positive voltage of 5V; pin 2 of the switch interface is connected to the sleep mode enable control pin of the controller U2 and connected to the analog ground through the resistor R3.

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