Vehicle-mounted start-stop power supply control circuit and vehicle-mounted power supply

Abstract

The utility model discloses a vehicle-mounted start-stop power supply control circuit and a vehicle-mounted power supply, and the vehicle-mounted start-stop power supply control circuit comprises a power supply input end and a power supply output end. The control circuit is arranged between the power supply input end and the power supply output end and is used for controlling the output voltage of the power supply output end according to the input voltage of the power supply input end; wherein the control circuit forms a booster circuit when the input voltage of the power supply input end is smaller than a set voltage, and forms a conduction circuit when the input voltage of the power supply input end is not smaller than the set voltage, so as to control the power supply output end to output an output voltage not smaller than the set voltage. Through the above structure, the stability of the output of the whole vehicle-mounted power supply is ensured.

Description

Technical Field

[0001] This application relates to the field of automotive electronics technology, and in particular to an on-board start-stop power supply control circuit and an on-board power supply. Background Technology

[0002] In order to achieve the goal of energy conservation and emission reduction, most automakers have applied engine start-stop technology in their new models. The principle is that when the vehicle is temporarily stopped during driving (such as waiting at a red light), the engine will automatically shut off. When the battery voltage drops below a certain value or when it is necessary to continue driving, the engine will automatically restart.

[0003] However, the power supply environment for automotive electronics is quite complex. The cockpit domain controller is designed to operate at 9V~16V. When the engine starts, the vehicle's battery voltage drops instantly from 12V to 4.5V, causing the domain controller to malfunction. The application of start-stop technology exacerbates this situation, resulting in a poor driving experience for the driver. Utility Model Content

[0004] The purpose of this invention is to provide an on-board start-stop power supply control circuit and an on-board power supply, which are used to ensure good EMC test results and to ensure the stability of power output.

[0005] To address the aforementioned technical problems, this application provides an on-board start-stop power supply control circuit, comprising: a power input terminal and a power output terminal; and a control circuit disposed between the power input terminal and the power output terminal, wherein the control circuit controls the output voltage of the power output terminal according to the input voltage of the power input terminal; wherein the control circuit forms a boost circuit when the input voltage of the power input terminal is less than a set voltage, and forms a conduction circuit when the input voltage of the power input terminal is not less than the set voltage, so as to control the power output terminal to output an output voltage not less than the set voltage.

[0006] Preferably, the control circuit includes: an inductor, a first end of which is connected to the power input terminal; a first MOSFET, the drain of which is connected to the second end of the inductor, and the source of which is connected to ground; and a second MOSFET, the source of which is connected to the second end of the inductor, and the drain of which is connected to the power output terminal.

[0007] Preferably, the vehicle start-stop power supply control circuit further includes a control chip; the control chip is connected to the gate of the first MOSFET and the gate of the second MOSFET, and is used to control the first MOSFET and the second MOSFET to conduct alternately when the input voltage at the power input terminal is less than a set voltage.

[0008] Preferably, the control chip is also connected to the power input terminal for detecting the input voltage of the power input terminal.

[0009] Preferably, the vehicle start-stop power supply control circuit further includes: a first resistor disposed between the power input terminal and the power output terminal, wherein the control chip is connected to both ends of the first resistor for detecting the current between the power input terminal and the power output terminal, and controlling the control circuit to shut down when the current is greater than a set value; wherein the first resistor is a fixed resistor.

[0010] Preferably, the vehicle start-stop power supply control circuit further includes: a second resistor and a third resistor connected in series; a first end of the second resistor is connected to the power output terminal, and a second end of the second resistor is connected to the third resistor; a first end of the third resistor is connected to the second end of the second resistor, and a second end of the third resistor is connected to ground; wherein, the second end of the second resistor is also connected to the control chip.

[0011] Preferably, the second MOSFET includes a body diode, the anode of which is connected to the inductor, and the cathode of which is connected to the power output terminal; wherein, when the second MOSFET is turned off under the control of the control chip, it supplies power to the power output terminal through the body diode.

[0012] Preferably, the vehicle start-stop power supply control circuit further includes: a controller; the controller is connected to the control chip, and controls the control chip to stop working when the control chip detects that the current is greater than a set value.

[0013] Preferably, the power output terminal is also connected to the controller via a subsequent step-down circuit to provide the controller with operating voltage so that the controller can operate.

[0014] To address the aforementioned technical problems, this application also provides an on-board power supply, which includes a vehicle power direct supply circuit and an on-board start-stop power control circuit as described in any of the above embodiments; wherein the vehicle power direct supply circuit is connected to the power output terminal of the on-board start-stop power control circuit.

[0015] The beneficial effects of this application are: when the input voltage is not less than the set voltage, the control circuit controls the second MOSFET to conduct, so that the output voltage at the power supply output terminal is not less than the set voltage. When the input voltage is less than the set voltage but greater than the operating voltage, the control circuit controls the first MOSFET and the second MOSFET to conduct alternately, thereby ensuring that the output voltage at the power supply output terminal is equal to the set voltage. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the vehicle start-stop power supply control circuit of this application;

[0018] Figure 2 This is a schematic diagram of the structure of an embodiment of the vehicle power supply of this application. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the application. The singular forms “a,” “said,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms, unless otherwise clearly indicated above. “Multiple” generally includes at least two, but does not exclude the inclusion of at least one.

[0021] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0022] It should be understood that the terms "comprising," "including," or any other variations used herein are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0023] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0024] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in every place in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0025] The present application will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0026] This application provides an on-board start-stop power supply control circuit; please refer to [link / reference]. Figure 1 , Figure 1 This is a schematic diagram of the overall structure of an embodiment of the vehicle start-stop power supply control circuit of this application, as shown below. Figure 1 As shown, the vehicle start-stop power supply control circuit includes: a power input terminal BAT, a power output terminal OUT, and a control circuit 10 disposed between the power input terminal BAT and the power output terminal OUT. The control circuit 10 controls the output voltage Vout of the power output terminal OUT according to the input voltage of the power input terminal BAT.

[0027] Specifically, the control circuit 10 forms a boost circuit when the input voltage at the power input terminal BAT is less than the set voltage V1, so as to control the power output terminal OUT to output an output voltage Vout not less than the set voltage V1; it also forms a normal conduction circuit when the input voltage at the power input terminal BAT is not less than the set voltage V1, so as to make the power output terminal OUT output an output voltage Vout not less than the set voltage V1.

[0028] In one specific embodiment, the control circuit 10 includes an inductor L1, a first MOSFET Q1, and a second MOSFET Q2. Specifically, the first terminal of the inductor L1 is connected to the power input terminal BAT, and the second terminal is connected to the first MOSFET Q1 and the second MOSFET Q2. The drain of the first MOSFET Q1 is connected to the second terminal of the inductor L1, and the source of the first MOSFET Q1 is connected to ground. The source of the second MOSFET Q2 is connected to the second terminal of the inductor L1, and the drain of the second MOSFET Q2 is connected to the power output terminal OUT. The gates of the first MOSFET Q1 and the second MOSFET Q2 are controlled by different control signal lines.

[0029] When the input voltage is less than the set voltage V1, the first MOSFET Q1 and the second MOSFET Q2 are alternately turned on by the control signal line to form a boost circuit with the inductor L1, thereby controlling the output voltage Vout of the power output terminal OUT to be no less than the set voltage V1.

[0030] When the input voltage is not less than the set voltage V1, the first MOSFET Q1 in the control circuit 10 is turned off, and the second MOSFET Q2 is turned on, thus forming a normal path with the inductor L1, ensuring that the output voltage Vout at the power output terminal OUT is not less than the set voltage V1. The output voltage Vout at the power output terminal OUT is related to the input voltage at the power input terminal BAT.

[0031] In the boost circuit, the output voltage Vout is controlled by controlling the conduction frequency of the first MOSFET Q1 and the second MOSFET Q2.

[0032] Furthermore, the vehicle start-stop power supply control circuit also includes a control chip 11, which is connected to the gate of the first MOSFET Q1 and the gate of the second MOSFET Q2. Specifically, the first pin DL of the control chip 11 is connected to the gate of the first MOSFET Q1, and the second pin DH is connected to the gate of the second MOSFET Q2. When the input voltage at the power input terminal BAT is less than the set voltage V1, the control chip 11 controls the first MOSFET Q1 and the second MOSFET Q2 to conduct alternately; or, when the input voltage at the power input terminal BAT is not less than the set voltage V1, the first MOSFET Q1 is turned off and the second MOSFET Q2 is turned on.

[0033] Furthermore, the control chip 11 also includes a third pin VIN, which is connected to the power input terminal BAT to detect the input voltage of the power input terminal BAT, compare the input voltage with the set voltage, and then control the first MOSFET Q1 and the second MOSFET Q2 through the first pin DL and the second pin DH.

[0034] The vehicle start-stop power supply control circuit also includes: a first resistor R1, which is positioned between the power input terminal BAT and the power output terminal OUT. The control chip 11 is connected to both ends of the first resistor R1 to detect the current between the power input terminal BAT and the power output terminal OUT, and controls the control circuit 10 to shut down when the current exceeds a set value. Specifically, the first resistor R1 is positioned between the power input terminal BAT and the inductor L1, with one end of the first resistor R1 connected to the power input terminal BAT and the other end connected to the first end of the inductor L1. The fourth pin SUP of the control chip 11 is connected to the second end of the first resistor R1, and the third pin VIN of the control chip 11 is connected to both the power input terminal BAT and the first end of the first resistor R1. The first resistor R1 is a fixed resistor. The voltage drop across the first resistor R1 is detected by the third pin VIN and the fourth pin SUP of the control chip 11. The current value I through the first resistor R1 is calculated based on the voltage drop and the fixed resistance value. When the current value I is greater than the set value, the control chip 11 controls the first MOSFET Q1 and the second MOSFET Q2 to turn off, thereby playing the role of overcurrent protection for the circuit.

[0035] The vehicle start-stop power supply control circuit also includes a second resistor R2 and a third resistor R3 connected in series. The first end of the second resistor R2 is connected to the power output terminal OUT, and the second end of the second resistor R2 is connected to the third resistor R3. The first end of the third resistor R3 is connected to the second end of the second resistor R2, and the second end of the third resistor R3 is connected to ground. The fifth pin FB of the control chip 11 is connected to the second end of the second resistor R2 and the first end of the third resistor R3. The second resistor R2 and the third resistor R3 are used to set the output voltage Vout of the power output terminal OUT. Specifically, the output voltage Vout of the power output terminal OUT is limited according to the ratio of the second resistor R2 to the third resistor R3. Specifically, the fifth pin FB of the control chip 11 detects the output voltage Vout of the power output terminal OUT through the second resistor R2 and the third resistor R3, and adjusts the output voltage Vout by controlling the switching on and off of the first MOSFET Q1 and the second MOSFET Q2 and their switching frequency based on the feedback voltage detected by the fifth pin FB.

[0036] The vehicle start-stop power supply control circuit also includes a controller (MCU) 12, which is connected to the control chip 11. The controller 12 enables the control chip 11, allowing it to operate and control the first MOSFET Q1 and the second MOSFET Q2. Specifically, the controller 12 controls the control chip 11 to stop operating when the current in the power path exceeds a set value. Specifically, the control chip 11 detects current through its third pin VIN and fourth pin SUP. When the detected current exceeds the set value, it transmits this information to the controller 12 via the PG pin. The controller 12 then disables the enable function for the control chip 11, thus stopping the control chip 11 and providing overcurrent protection for the circuit.

[0037] Furthermore, the second MOSFET Q2 includes a body diode. The anode of the body diode of the second MOSFET Q2 is connected to the inductor L1, and the cathode of the body diode of the second MOSFET Q2 is connected to the power output terminal OUT. When the second MOSFET Q2 is turned off under the control of the control chip 11, it can still supply power to the power output terminal OUT through its body diode. However, at this time, the second MOSFET Q2 is in the off state, the body diode has a larger resistance, and the resulting voltage drop is larger.

[0038] In this embodiment, the power output terminal OUT is also connected to the controller 12 via the subsequent step-down circuit 13. Upon power-up, the input voltage of the power input terminal BAT supplies power to the subsequent step-down circuit 13 through the body diode of the second MOSFET Q2, which in turn supplies power to the controller 12. The controller 12 enables the control chip 11. After being enabled by the controller 12, the control chip 11 detects the input voltage of the power input terminal BAT through its third pin VIN and compares it with a set voltage. When the input voltage is greater than the set voltage, the control chip 11 controls the second MOSFET Q2 to turn on through its first pin DH. After the second MOSFET Q2 turns on, its on-resistance is much smaller than the resistance of its body diode, effectively reducing power consumption.

[0039] It should be noted that controller 12 also requires an operating voltage, which is much lower than the set voltage. Therefore, even when the second MOSFET Q2 is off, the voltage flowing through its body diode can still enable controller 12 to operate. Specifically, when control chip 11 detects that the input voltage is lower than the set voltage but higher than the operating voltage, it controls the first MOSFET Q1 and the second MOSFET Q2 to periodically switch on and off, thus forming a boost circuit together with inductor L1. The output voltage of the boost circuit is the set voltage. This ensures that even when the input voltage at the power input terminal BAT drops significantly during engine startup, the start-stop circuit can still provide a stable set voltage output to the downstream power supply, thereby ensuring that the entire power supply system can still operate normally.

[0040] It should be noted that the resistance value of the first resistor R1 is small and its voltage drop in the power supply circuit can be ignored. When the second MOSFET Q2 is turned on, the output voltage of the power supply output terminal OUT is approximately equal to the input voltage of the power supply input terminal BAT.

[0041] In this embodiment, when the input voltage is not less than the set voltage, the control chip 11 controls the second MOSFET Q2 to conduct. The power supply path is from the power input terminal BAT through the first resistor R1, inductor L1, and the second MOSFET Q2 to the power output terminal OUT, ensuring that the output voltage of the power output terminal OUT is not less than the set voltage. When the input voltage is less than the set voltage but greater than the operating voltage, the control chip 11 controls the first MOSFET Q1 and the second MOSFET Q2 to conduct alternately, forming a boost circuit with the inductor L1, thereby ensuring that the output voltage of the power output terminal OUT is the set voltage.

[0042] This application also provides a vehicle-mounted power supply; please refer to the details. Figure 2 , Figure 2 This is a structural schematic diagram of an embodiment of the vehicle-mounted power supply of this application. Figure 2 As shown, the vehicle power supply includes a vehicle start-stop power control circuit 100 and a vehicle power direct supply circuit 200. The vehicle start-stop power control circuit 100 is the same as described in any of the above embodiments. The vehicle power direct supply circuit 200 is used to supply power to the vehicle threshold control system. The input terminal of the vehicle power direct supply circuit 200 is connected to the power output terminal OUT of the vehicle start-stop power control circuit 100. The vehicle start-stop power control circuit 100 ensures that the voltage input to the vehicle power direct supply circuit 200 is not lower than a set voltage, thereby ensuring that each module in the vehicle threshold control system can operate normally.

[0043] The beneficial effects of this application are: when the input voltage is not less than the set voltage, the control circuit controls the second MOSFET Q2 to conduct, so that the output voltage of the power output terminal OUT is not less than the set voltage. When the input voltage is less than the set voltage but greater than the operating voltage, the control circuit controls the first MOSFET Q1 and the second MOSFET Q2 to conduct alternately, thereby ensuring that the output voltage of the power output terminal OUT is equal to the set voltage.

[0044] The above description is merely an embodiment of this application and does not limit the scope of patent protection of this application. Any equivalent structural or procedural changes made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A vehicle start-stop power supply control circuit, characterized in that, include: Power input terminal and power output terminal; A control circuit is disposed between the power input terminal and the power input terminal. The control circuit includes an inductor, a first MOSFET, and a second MOSFET. The first end of the inductor is connected to the power input terminal. The drain of the first MOSFET is connected to the second end of the inductor, and the source of the first MOSFET is connected to ground. The source of the second MOSFET is connected to the second end of the inductor, and the drain of the second MOSFET is connected to the power output terminal. Specifically, when the input voltage at the power input terminal is less than a set voltage, the control circuit controls the first MOSFET and the second MOSFET to conduct alternately, forming a boost circuit with the inductor, thereby controlling the power output terminal to output an output voltage not less than the set voltage; when the input voltage at the power input terminal is not less than the set voltage, the control circuit controls the first MOSFET to turn off and the second MOSFET to conduct, forming a conduction circuit with the inductor, thereby controlling the power output terminal to output an output voltage not less than the set voltage.

2. The vehicle start-stop power supply control circuit according to claim 1, characterized in that, The vehicle start-stop power supply control circuit also includes a control chip; The control chip is connected to the gate of the first MOS transistor and the gate of the second MOS transistor, and is used to control the first MOS transistor and the second MOS transistor to conduct alternately when the input voltage at the power input terminal is less than a set voltage.

3. The vehicle start-stop power supply control circuit according to claim 2, characterized in that, The control chip is also connected to the power input terminal to detect the input voltage of the power input terminal.

4. The vehicle start-stop power supply control circuit according to claim 2, characterized in that, The vehicle start-stop power supply control circuit also includes: A first resistor is disposed between the power input terminal and the power output terminal. The control chip is connected to both ends of the first resistor to detect the current between the power input terminal and the power output terminal, and to control the control circuit to shut down when the current is greater than a set value. The first resistor is a fixed resistor.

5. The vehicle start-stop power supply control circuit according to claim 2, characterized in that, The vehicle start-stop power supply control circuit also includes: a second resistor and a third resistor connected in series; The first end of the second resistor is connected to the power output terminal, and the second end of the second resistor is connected to the third resistor; The first end of the third resistor is connected to the second end of the second resistor, and the second end of the third resistor is connected to the ground wire; The second end of the second resistor is also connected to the control chip.

6. The vehicle start-stop power supply control circuit according to claim 3, characterized in that, The second MOSFET includes a body diode, the anode of which is connected to the inductor, and the cathode of which is connected to the power output terminal. When the second MOSFET is turned off under the control of the control chip, it supplies power to the power output terminal through the body diode.

7. The vehicle start-stop power supply control circuit according to claim 4, characterized in that, The vehicle start-stop power supply control circuit also includes: a controller; The controller is connected to the control chip, and when the control chip detects that the current is greater than a set value, the controller stops working.

8. The vehicle start-stop power supply control circuit according to claim 7, characterized in that, The power output terminal is also connected to the controller via a subsequent step-down circuit to provide the controller with operating voltage, enabling the controller to operate.

9. A vehicle-mounted power supply, characterized in that, The vehicle power supply includes a vehicle power direct supply circuit and a vehicle start-stop power control circuit as described in any one of claims 1 to 8. The vehicle power supply circuit is connected to the power output terminal of the vehicle start-stop power control circuit.

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