Power supply reverse connection prevention circuit and vehicle body controller

Abstract

The utility model discloses a power supply anti-reverse connection circuit and a vehicle body controller. The circuit comprises a switch unit, a controller and an anti-reverse connection circuit unit, the switch unit comprises a power supply end, a grounding end and a communication end, and the grounding end is grounded; the anti-reverse connection circuit unit is connected between the controller and the communication end of the switch unit; the anti-reverse connection circuit unit is also grounded; the anti-reverse-connection circuit unit is used for connecting the controller and the communication end of the switch unit when the power supply end is positively connected, and the controller communicates with the switch unit through the anti-reverse-connection circuit unit to control the switch-on or switch-off of the switch unit; and the anti-reverse connection circuit unit is also used for disconnecting the controller from the communication end of the switch unit when the power supply end is reversely connected, and the switch unit is turned off. The problem that the controller is damaged due to the fact that the current flowing through the controller interface is too large when the power supply is reversely connected is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, in particular to a power supply reverse connection prevention circuit and a vehicle body controller. Background Art

[0002] As the integration of body controllers becomes higher and higher, the loads that need to be driven by them will also increase. Body controllers usually use multiple high-side switches to drive the loads, and the high-side switches are controlled by the controller, which can be a microcontroller unit (MCU). The use of multiple high-side switches will consume a lot of controller interfaces. In order to save controller interfaces, high-side switches with serial peripheral interfaces (SPI) are selected, and time-division multiplexing connection is adopted.

[0003] With the above connection method, the controller interface will receive clock signals or master-send-slave-receive signals from multiple SPI communication interfaces. If the power supply is reversed, the current flowing through the controller interface will increase greatly, and may even exceed the maximum current that the controller interface can withstand, thereby damaging the controller. Utility Model Content

[0004] The utility model provides a power supply reverse connection prevention circuit and a vehicle body controller, so as to solve the problem that the controller is easily damaged when the power supply is reversely connected.

[0005] In a first aspect, the utility model provides a power supply reverse connection protection circuit, the circuit comprising: a switch unit, a controller and a reverse connection protection circuit unit;

[0006] The switch unit includes a power supply terminal, a ground terminal and a communication terminal, and the ground terminal is grounded; the anti-reverse connection circuit unit is connected between the controller and the communication terminal of the switch unit; the anti-reverse connection circuit unit is also grounded;

[0007] The anti-reverse connection circuit unit is used to connect the connection between the communication end of the controller and the switch unit when the power supply end is connected positively. The controller communicates with the switch unit through the anti-reverse connection circuit unit to control the switch unit to be turned on or off. The anti-reverse connection circuit unit is also used to disconnect the connection between the communication end of the controller and the switch unit when the power supply end is connected reversely, and the switch unit is turned off.

[0008] In a second aspect, the utility model provides a vehicle body controller, which includes the power reverse connection protection circuit provided in the first aspect.

[0009] The technical solution of the utility model provides a power supply reverse connection protection circuit and a vehicle body controller. By setting the reverse connection protection circuit unit, when the power supply end is reversed, the reverse connection protection circuit unit will disconnect the communication between the controller and the switch unit, and the switch unit is always in the off state. This prevents current from flowing through the interface of the controller, thus avoiding the problem of excessive current flowing through the interface of the controller when the power supply is reversed, thereby damaging the controller.

[0010] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present utility model, nor are they intended to limit the scope of the present utility model. Other features of the present utility model will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0012] Figure 1 It is a structural schematic diagram of a power supply reverse connection protection circuit provided by an embodiment of the utility model;

[0013] Figure 2 It is a structural schematic diagram of another power supply reverse connection protection circuit provided by an embodiment of the utility model;

[0014] Figure 3 It is a structural schematic diagram of another power supply reverse connection protection circuit provided by an embodiment of the utility model;

[0015] Figure 4 It is a structural schematic diagram of another power supply reverse connection protection circuit provided by an embodiment of the utility model;

[0016] Figure 5 It is a structural schematic diagram of another power supply reverse connection protection circuit provided by an embodiment of the utility model;

[0017] Figure 6 It is a structural schematic diagram of another power supply reverse connection protection circuit provided by an embodiment of the utility model;

[0018] Figure 7 It is a structural schematic diagram of another power supply reverse connection protection circuit provided by an embodiment of the utility model;

[0019] Figure 8 It is a structural schematic diagram of another power supply reverse connection protection circuit provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0021] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model 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 data used in this way can be interchanged where appropriate, so that the embodiments of the utility model described here can be implemented in an order other than those illustrated or described here. 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 clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0022] Figure 1 Schematic diagram of a power supply reverse connection protection circuit provided by the embodiment of the utility model. Figure 1 As shown, the circuit includes: a switch unit 1, a controller 2 and an anti-reverse connection circuit unit 3.

[0023] The switch unit 1 includes a power supply terminal VS, a ground terminal D and a communication terminal CO, wherein the ground terminal D is connected to the ground GND; the anti-reverse connection circuit unit 3 is connected between the controller 2 and the communication terminal CO of the switch unit 1; and the anti-reverse connection circuit unit 3 is also connected to the ground GND.

[0024] The anti-reverse connection circuit unit 3 is used to connect the connection between the controller 2 and the communication terminal CO of the switch unit 1 when the power terminal VS is connected in the positive direction. The controller 2 communicates with the switch unit 1 through the anti-reverse connection circuit unit 3 to control the switch unit 1 to be turned on or off. The anti-reverse connection circuit unit 3 is also used to disconnect the connection between the controller 2 and the communication terminal CO of the switch unit 1 when the power terminal VS is connected in the reverse direction, and the switch unit 1 is turned off.

[0025] In this embodiment, the switch unit 1 is a circuit unit with a communication interface, for example, it can be a circuit element with an SPI communication interface. The controller 2 is a unit that controls the switch unit 1 to be turned on or off by communicating with the switch unit 1. For example, the controller 2 can be an MCU. The anti-reverse connection circuit unit 3 is mainly used to disconnect the communication between the controller 2 and the switch unit 1 when the power supply terminal VS is reversely connected.

[0026] Specifically, the power supply reverse connection protection circuit may include one switch unit 1, or may include multiple switch units 1. The switch unit 1 includes a power supply terminal VS, a ground terminal D and a communication terminal CO, the power supply terminal VS is connected to the power supply VBAT, the ground terminal D is connected to GND, and the communication terminal CO is used to communicate with the controller 2. The switch unit 1 may also include an output terminal, which is connected to an external load. When the switch unit 1 is turned on, the power supply VBAT supplies power to the load through the power supply terminal VS and the output terminal; when the switch unit 1 is turned off, the power supply terminal VS is disconnected from the output terminal, and the power supply VBAT cannot supply power to the load. One end of the anti-reverse connection circuit unit 3 is connected to the controller 2, and the other end is connected to the communication terminal CO of the switch unit 1, and the anti-reverse connection circuit unit 3 is also connected to the ground GND.

[0027] When the power supply terminal VS is connected in a positive direction, that is, the power supply terminal VS is connected to the power supply VBAT, the ground terminal D is connected to the ground GND, and the anti-reverse connection circuit unit 3 is connected to the ground GND, the controller 2 can be connected to the communication terminal CO of the switch unit 1 through the anti-reverse connection circuit unit 3, and communicate with the switch unit 1. At this time, the controller 2 can control the switch unit 1 to be turned on or off. When the power supply terminal VS is reversely connected, that is, the power supply terminal VS is connected to the ground GND, the ground terminal D is connected to the power supply VBAT, and the anti-reverse connection circuit unit 3 is connected to the power supply VBAT. At this time, the anti-reverse connection circuit unit 3 disconnects the connection between the controller 2 and the communication terminal CO of the switch unit 1, and the controller 2 cannot communicate with the switch unit 1, and the switch unit 1 is always in the off state. Since the anti-reverse connection circuit unit 3 will disconnect the communication between the controller 2 and the switch unit 1 when the power supply terminal VS is reversely connected, no current will flow through the interface of the controller 2.

[0028] The technical solution of this embodiment provides a power supply reverse connection protection circuit, which is provided with a reverse connection protection circuit unit. When the power supply end is reversely connected, the reverse connection protection circuit unit will disconnect the communication between the controller and the switch unit, and the switch unit is always in the off state. This prevents current from flowing through the interface of the controller, thus avoiding the problem of excessive current flowing through the interface of the controller when the power supply is reversely connected, thereby damaging the controller.

[0029] Figure 2 Schematic diagram of another power supply reverse connection protection circuit provided by the embodiment of the utility model. Figure 2As shown, the communication end includes a first SPI communication interface CLK, a second SPI communication interface MOSI, a third SPI communication interface MISO and a chip select communication interface CS1; the controller 2 is respectively connected to an anti-reverse connection circuit unit 3 and the chip select communication interface CS1, and the anti-reverse connection circuit unit 3 is respectively connected to the first SPI communication interface CLK, the second SPI communication interface MOSI and the third SPI communication interface MISO; the anti-reverse connection circuit unit 3 is used to connect the controller 2 with the first SPI communication interface CLK, the second SPI communication interface MOSI and the third SPI communication interface MISO when the power supply terminal VS is positively connected; the anti-reverse connection circuit unit 3 is also used to disconnect the controller 2 with the first SPI communication interface CLK, the second SPI communication interface MOSI and the third SPI communication interface MISO when the power supply terminal VS is reversely connected.

[0030] Specifically, the controller 2 includes an A interface, a B interface, and a C interface. The communication end of the switch unit 1 includes a first SPI communication interface CLK, a second SPI communication interface MOSI, a third SPI communication interface MISO, and a chip select communication interface CS1. The chip select communication interface CS1 is connected to the controller 2, and the anti-reverse connection circuit unit 3 is respectively connected to the first SPI communication interface CLK, the second SPI communication interface MOSI, and the third SPI communication interface MISO. The A interface, the B interface, and the C interface of the controller 2 are respectively connected to the anti-reverse connection circuit unit 3.

[0031] When the power supply terminal VS is positively connected, the controller 2 sends a first conduction signal or a signal with a level opposite to the first conduction signal to the chip select communication interface CS1. Exemplarily, the first conduction signal can be a low level. The A interface of the controller 2 is connected to the first SPI communication interface CLK through the anti-reverse connection circuit unit 3, the B interface of the controller 2 is connected to the second SPI communication interface MOSI through the anti-reverse connection circuit unit 3, and the C interface of the controller 2 is connected to the third SPI communication interface MISO through the anti-reverse connection circuit unit 3. When the controller 2 sends the first conduction signal to the chip select communication interface CS1, and the A interface and the B interface of the controller 2 send correct communication signals to the first SPI communication interface CLK and the second SPI communication interface MOSI respectively, the switch unit 1 is turned on, and the switch unit 1 feeds back its working status to the C interface of the controller 2 through the third SPI communication interface MISO. When the controller 2 sends a signal with a level opposite to that of the first on-signal to the chip select communication interface CS1, regardless of whether the A interface and the B interface of the controller 2 send correct communication signals to the first SPI communication interface CLK and the second SPI communication interface MOSI, the switch unit 1 is always in the off state, and the switch unit 1 feeds back its working status to the C interface of the controller 2 through the third SPI communication interface MISO.

[0032] When the power supply terminal VS is reversely connected, the anti-reverse connection circuit unit 3 disconnects the connection between the A interface of the controller 2 and the first SPI communication interface CLK, disconnects the connection between the B interface of the controller 2 and the second SPI communication interface MOSI, and disconnects the C interface of the controller 2 and the third SPI communication interface MISO. Regardless of whether the controller 2 sends the first conduction signal or sends a signal with a level opposite to the first conduction signal to the chip selection communication interface CS1, the switch unit 1 is always in the off state. No current will flow through the A interface, B interface and C interface of the controller connected to the first SPI communication interface CLK, the second SPI communication interface MOSI and the third SPI communication interface MISO, respectively, thereby preventing the controller from being damaged due to excessive interface current.

[0033] Figure 3 Schematic diagram of another power supply reverse connection protection circuit provided by the embodiment of the utility model. Figure 3 As shown, there are at least two switch units 1, and the first SPI communication interface CLK, the second SPI communication interface MOSI, and the third SPI communication interface MISO of each switch unit 1 are respectively connected to the first communication bus, the second communication bus, and the third communication bus; the anti-reverse connection circuit unit 3 is connected to the first communication bus, the second communication bus, and the third communication bus.

[0034] Specifically, the power reverse connection protection circuit may include two switch units 1, or may include multiple switch units 1. The first SPI communication interface CLK of each switch unit 1 is connected to the first communication bus, the second SPI communication interface MOSI of each switch unit 1 is connected to the second communication bus, and the third SPI communication interface MISO of each switch unit 1 is connected to the third communication bus. The reverse connection protection circuit unit 3 is connected to the first communication bus, the second communication bus, and the third communication bus, respectively.

[0035] The controller 2 may further include an E interface and an F interface, and the chip selection communication interface CS1 of each switch unit 1 is connected to different interfaces of the controller 2. Figure 2 As shown, the chip select communication interface CS1 of one switch unit 1 is connected to the E interface of the controller 2 , and the chip select communication interface CS1 of another switch unit 1 is connected to the F interface of the controller 2 .

[0036] When the power supply terminal VS is positively connected, the E interface of the controller 2 sends the first conduction signal or a signal with a level opposite to the first conduction signal to the chip select communication interface CS1, and the F interface of the controller 2 sends the first conduction signal or a signal with a level opposite to the first conduction signal to the chip select communication interface CS1. And the A interface and the B interface of the controller 2 send the correct communication signal to the first SPI communication interface CLK and the second SPI communication interface MOSI of each switch unit 1 respectively. The controller 2 controls the E interface and the F interface to send the first conduction signal or a signal with a level opposite to the first conduction signal, thereby realizing that at least one switch unit 1 is turned on or all switch units 1 are turned on. Each switch unit 1 feeds back its working status to the C interface of the controller 2 through the third SPI communication interface MISO.

[0037] When the power supply terminal VS is reversely connected, the anti-reverse connection circuit unit 3 disconnects the connection between the A interface of the controller 2 and the first SPI communication interface CLK of each switch unit 1, disconnects the connection between the B interface of the controller 2 and the second SPI communication interface MOSI of each switch unit 1, disconnects the connection between the C interface of the controller 2 and the third SPI communication interface MISO of each switch unit 1, and the switch unit 1 is always in the off state. No current will flow through the A interface, B interface and C interface of the controller connected to the first SPI communication interface CLK, the second SPI communication interface MOSI and the third SPI communication interface MISO, respectively, thereby preventing the controller 2 from being damaged due to excessive interface current.

[0038] Figure 4 Schematic diagram of another power supply reverse connection protection circuit provided by the embodiment of the utility model. Figure 4 As shown, the anti-reverse connection circuit unit 3 includes: a first switch 31, a second switch 32, a third switch 33, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5 and a sixth resistor R6.

[0039] The first end of the first switch 31 is connected to the controller 2, the second end of the first switch 31 is connected to the first SPI communication interface CLK, the control end of the first switch 31 is connected to the first end of the first resistor R1, and the second end of the first resistor R1 is grounded GND; the fourth resistor R4 is connected between the first end and the control end of the first switch 31; the first switch 31 is used to connect the controller 2 with the first SPI communication interface CLK when the power supply terminal VS is positively connected; and is also used to disconnect the controller 2 from the first SPI communication interface CLK when the power supply terminal VS is reversely connected.

[0040] The first end of the second switch 32 is connected to the controller 2, the second end of the second switch 32 is connected to the second SPI communication interface MOSI, the control end of the second switch 32 is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is grounded GND; the fifth resistor R5 is connected between the first end and the control end of the second switch 32; the second switch 32 is used to connect the connection between the controller 2 and the second SPI communication interface MOSI when the power supply terminal VS is positively connected; and is also used to disconnect the connection between the controller 2 and the second SPI communication interface MOSI when the power supply terminal VS is reversely connected.

[0041] A first end of the third switch 33 is connected to the controller 2, a second end of the third switch 33 is connected to the third SPI communication interface MISO, a control end of the third switch 33 is connected to a first end of a third resistor R3, and a second end of the third resistor R3 is grounded GND; a sixth resistor R6 is connected between the first end and the control end of the third switch 33; the third switch 33 is used to connect the controller 2 to the third SPI communication interface MISO when the power supply terminal VS is positively connected; and is also used to disconnect the controller 2 from the third SPI communication interface MISO when the power supply terminal VS is reversely connected.

[0042] Specifically, the first switch 31, the second switch 32 and the third switch 33 include but are not limited to bipolar transistors or field effect transistors. The first end of the first switch 31 is connected to the A interface of the controller 2, the second end of the first switch 31 is connected to the first SPI communication interface CLK, and the first resistor R1 is connected between the control end of the first switch 31 and the ground GND. The fourth resistor R4 is connected between the first end and the control end of the first switch 31. The first end of the second switch 32 is connected to the B interface of the controller 2, the second end of the second switch 32 is connected to the second SPI communication interface MOSI, and the second resistor R2 is connected between the control end of the second switch 32 and the ground GND. The fifth resistor R5 is connected between the first end and the control end of the second switch 32. The first end of the third switch 33 is connected to the C interface of the controller 2, the second end of the third switch 33 is connected to the third SPI communication interface MISO, and the third resistor R3 is connected between the control end of the third switch 33 and the ground GND. The sixth resistor R6 is connected between the first end and the control end of the third switch 33.

[0043] When the power supply terminal VS is positively connected, the control end of the first switch 31 is grounded to GND through the first resistor R1, and the fourth resistor R4 generates a voltage difference between the first end and the control end of the first switch 31, providing a bias voltage for the first switch 31, so the first switch 31 is turned on. The control end of the second switch 32 is grounded to GND through the second resistor R2, and the fifth resistor R5 generates a voltage difference between the first end and the control end of the second switch 32, providing a bias voltage for the second switch 32, so the second switch 32 is turned on. The control end of the third switch 33 is grounded to GND through the third resistor R3, and the sixth resistor R6 generates a voltage difference between the first end and the control end of the third switch 33, providing a bias voltage for the third switch 33, so the third switch 33 is turned on. The A interface of the controller 2 is connected to the first SPI communication interface CLK through the first switch 31, the B interface of the controller 2 is connected to the second SPI communication interface MOSI through the second switch 32, and the C interface of the controller 2 is connected to the third SPI communication interface MISO through the third switch 33.

[0044] When the power supply terminal VS is reversely connected, the control end of the first switch 31 is connected to the power supply VBAT through the first resistor R1, so the first switch 31 is turned off. The control end of the second switch 32 is connected to the power supply VBAT through the second resistor R2, so the second switch 32 is turned off. The control end of the third switch 33 is connected to the power supply VBAT through the third resistor R3, so the third switch 33 is turned off. The first switch 31 disconnects the A interface of the controller 2 from the first SPI communication interface CLK, the second switch 32 disconnects the B interface of the controller 2 from the second SPI communication interface MOSI, and the third switch 33 disconnects the C interface of the controller 2 from the third SPI communication interface MISO.

[0045] Figure 5 Schematic diagram of another power supply reverse connection protection circuit provided by the embodiment of the utility model. Figure 5 As shown, the first switch 31 includes a first PMOS transistor Q1 , the second switch 32 includes a second PMOS transistor Q2 , and the third switch 33 includes a third PMOS transistor Q3 .

[0046] The gate of the first PMOS transistor Q1 serves as the control terminal of the first switch 31 , the source of the first PMOS transistor Q1 serves as the first terminal of the first switch 31 , and the drain of the first PMOS transistor Q1 serves as the second terminal of the first switch 31 .

[0047] The gate of the second PMOS transistor Q2 serves as the control end of the second switch 32 , the source of the second PMOS transistor Q2 serves as the first end of the second switch 32 , and the drain of the second PMOS transistor Q2 serves as the second end of the second switch 32 .

[0048] The gate of the third PMOS transistor Q3 serves as the control terminal of the third switch 33 , the source of the third PMOS transistor Q3 serves as the first terminal of the third switch 33 , and the drain of the third PMOS transistor Q3 serves as the second terminal of the third switch 33 .

[0049] Specifically, when the power supply terminal VS is positively connected, the A interface of the controller 2 is connected to the first SPI communication interface CLK through the first PMOS tube Q1, the B interface of the controller 2 is connected to the second SPI communication interface MOSI through the second PMOS tube Q2, and the C interface of the controller 2 is connected to the third SPI communication interface MISO through the third PMOS tube Q3. And the current flowing through the first PMOS tube Q1, the second PMOS tube Q2 and the third PMOS tube Q3 is very small, so the first PMOS tube Q1, the second PMOS tube Q2 and the third PMOS tube Q3 can use signal-level PMOS. This arrangement avoids the problem of large power loss and severe temperature rise of the PMOS tube, thereby increasing the cost of power supply reverse connection protection.

[0050] When the power supply terminal VS is reversed, the first PMOS tube Q1 disconnects the A interface of the controller 2 from the first SPI communication interface CLK, the second PMOS tube Q2 disconnects the B interface of the controller 2 from the second SPI communication interface MOSI, and the third PMOS tube Q3 disconnects the C interface of the controller 2 from the third SPI communication interface MISO.

[0051] Figure 6 Schematic diagram of another power supply reverse connection protection circuit provided by the embodiment of the utility model. Figure 6 As shown, the anti-reverse connection circuit unit 3 further includes: a first TVS tube D1, a second TVS tube D2 and a third TVS tube D3.

[0052] A first end of the first TVS tube D1 is connected to a first end of the first switch 31 , and a second end of the first TVS tube D1 is connected to a control end of the first switch 31 .

[0053] A first end of the second TVS tube D2 is connected to a first end of the second switch 32 , and a second end of the second TVS tube D2 is connected to a control end of the second switch 32 .

[0054] A first end of the third TVS tube D3 is connected to a first end of the third switch 33 , and a second end of the third TVS tube D3 is connected to a control end of the third switch 33 .

[0055] Specifically, the first TVS tube D1 is connected between the first end and the control end of the first switch 31, the second TVS tube D2 is connected between the first end and the control end of the second switch 32, and the third TVS tube D3 is connected between the first end and the control end of the third switch. The first TVS tube D1, the second TVS tube D2, and the third TVS tube D3 can clamp the voltage difference between the first end and the control end of the first switch 31, the second switch 32, and the third switch 33 at a certain value, which not only satisfies the conduction condition of the first switch 31, the second switch 32, and the third switch 33, but also prevents the voltage input to the first end of the first switch 31, the second switch 32, and the third switch 33 from being too large to break down the first switch 31, the second switch 32, and the third switch 33.

[0056] Figure 7 Schematic diagram of another power supply reverse connection protection circuit provided by the embodiment of the utility model. Figure 7 As shown, the anti-reverse connection circuit unit 3 further includes: a seventh resistor R7, an eighth resistor R8 and a ninth resistor R9.

[0057] A first end of the seventh resistor R7 is connected to the controller 2 , and a second end of the seventh resistor R7 is connected to a first end of the first switch 31 .

[0058] A first end of the eighth resistor R8 is connected to the controller 2 , and a second end of the eighth resistor R8 is connected to a first end of the second switch 32 .

[0059] A first end of the ninth resistor R9 is connected to the controller 2 , and a second end of the ninth resistor R9 is connected to a first end of the third switch 33 .

[0060] Specifically, the seventh resistor R7 is connected between the A interface of the controller 2 and the first end of the first switch 31, the eighth resistor R8 is connected between the B interface of the controller 2 and the first end of the second switch 32, and the ninth resistor R9 is connected between the C interface of the controller 2 and the first end of the third switch 33. The seventh resistor R7, the eighth resistor R8 and the ninth resistor R9 mainly play a role of current limiting protection, which can be used to provide current limiting protection for the A interface, the B interface and the C interface of the controller 2, and can also provide current limiting protection for the first switch 31, the second switch 32 and the third switch 33.

[0061] Figure 8 Schematic diagram of another power supply reverse connection protection circuit provided by the embodiment of the utility model. Figure 8 As shown, the circuit also includes: a tenth resistor R10.

[0062] A first end of the tenth resistor R10 is connected to the controller 2 , and a second end of the tenth resistor R10 is connected to the chip selection communication interface CS1 .

[0063] Specifically, the tenth resistor R10 is connected between the controller 2 and the chip selection communication interface CS1 , and mainly plays a current limiting protection role for the interface of the controller 2 .

[0064] Optionally, the switch unit includes a high-side driver chip with a communication function.

[0065] In this embodiment, the high-side driver chip is a chip with a communication function.

[0066] Specifically, the high-side driver chip includes a power pin, an output pin, a ground pin and a communication pin. The power pin serves as the power supply end of the switch unit, the output pin serves as the output end of the switch unit, the ground pin serves as the ground end of the switch unit, and the communication pin serves as the communication end of the switch unit.

[0067] An embodiment of the utility model provides a vehicle body controller, which includes the power reverse connection protection circuit provided in any of the above embodiments, and has the beneficial effects of the power reverse connection protection circuit in any of the above embodiments of the utility model.

[0068] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0069] The above specific implementations do not constitute a limitation on the protection scope of the present utility model. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A power supply reverse connection protection circuit, characterized in that: include: Switch unit, controller and anti-reverse connection circuit unit; The switch unit comprises a power supply terminal, a ground terminal and a communication terminal, wherein the ground terminal is grounded; the anti-reverse connection circuit unit is connected between the controller and the communication terminal of the switch unit; the anti-reverse connection circuit unit is also grounded; The anti-reverse connection circuit unit is used to connect the connection between the controller and the communication end of the switch unit when the power supply end is connected in a positive direction, and the controller communicates with the switch unit through the anti-reverse connection circuit unit to control the switch unit to be turned on or off; the anti-reverse connection circuit unit is also used to disconnect the connection between the controller and the communication end of the switch unit when the power supply end is connected in a reverse direction, and the switch unit is turned off; The communication end includes a first SPI communication interface, a second SPI communication interface, a third SPI communication interface and a chip select communication interface; the controller is respectively connected to the anti-reverse connection circuit unit and the chip select communication interface, and the anti-reverse connection circuit unit is respectively connected to the first SPI communication interface, the second SPI communication interface and the third SPI communication interface; the anti-reverse connection circuit unit is used to connect the connection between the controller and the first SPI communication interface, the second SPI communication interface and the third SPI communication interface when the power end is positively connected; the anti-reverse connection circuit unit is also used to disconnect the connection between the controller and the first SPI communication interface, the second SPI communication interface and the third SPI communication interface when the power end is reversely connected.

2. The power supply reverse connection protection circuit according to claim 1, characterized in that: There are at least two switch units, and the first SPI communication interface, the second SPI communication interface, and the third SPI communication interface of each switch unit are connected to the first communication bus, the second communication bus, and the third communication bus respectively; the anti-reverse connection circuit unit is connected to the first communication bus, the second communication bus, and the third communication bus.

3. The power supply reverse connection protection circuit according to claim 1, characterized in that: The anti-reverse connection circuit unit comprises: a first switch, a second switch, a third switch, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor and a sixth resistor; The first end of the first switch is connected to the controller, the second end of the first switch is connected to the first SPI communication interface, the control end of the first switch is connected to the first end of the first resistor, and the second end of the first resistor is grounded; the fourth resistor is connected between the first end and the control end of the first switch; the first switch is used to connect the controller to the first SPI communication interface when the power end is positively connected; and is also used to disconnect the controller from the first SPI communication interface when the power end is reversely connected; The first end of the second switch is connected to the controller, the second end of the second switch is connected to the second SPI communication interface, the control end of the second switch is connected to the first end of the second resistor, and the second end of the second resistor is grounded; the fifth resistor is connected between the first end and the control end of the second switch; the second switch is used to connect the controller to the second SPI communication interface when the power supply end is positively connected; and is also used to disconnect the controller from the second SPI communication interface when the power supply end is reversely connected; The first end of the third switch is connected to the controller, the second end of the third switch is connected to the third SPI communication interface, the control end of the third switch is connected to the first end of the third resistor, and the second end of the third resistor is grounded; the sixth resistor is connected between the first end and the control end of the third switch; the third switch is used to connect the connection between the controller and the third SPI communication interface when the power supply end is positively connected; and is also used to disconnect the connection between the controller and the third SPI communication interface when the power supply end is reversely connected.

4. The power supply reverse connection protection circuit according to claim 3, characterized in that: The first switch includes a first PMOS transistor, the second switch includes a second PMOS transistor, and the third switch includes a third PMOS transistor; The gate of the first PMOS transistor serves as the control end of the first switch, the source of the first PMOS transistor serves as the first end of the first switch, and the drain of the first PMOS transistor serves as the second end of the first switch; The gate of the second PMOS tube serves as the control terminal of the second switch, the source of the second PMOS tube serves as the first terminal of the second switch, and the drain of the second PMOS tube serves as the second terminal of the second switch; The gate of the third PMOS tube serves as the control end of the third switch, the source of the third PMOS tube serves as the first end of the third switch, and the drain of the third PMOS tube serves as the second end of the third switch.

5. The power reverse connection protection circuit according to claim 3, characterized in that: The anti-reverse connection circuit unit further includes: a first TVS tube, a second TVS tube and a third TVS tube; The first end of the first TVS tube is connected to the first end of the first switch, and the second end of the first TVS tube is connected to the control end of the first switch; The first end of the second TVS tube is connected to the first end of the second switch, and the second end of the second TVS tube is connected to the control end of the second switch; The first end of the third TVS tube is connected to the first end of the third switch, and the second end of the third TVS tube is connected to the control end of the third switch.

6. The power supply reverse connection protection circuit according to claim 3, characterized in that: The anti-reverse connection circuit unit further includes: a seventh resistor, an eighth resistor and a ninth resistor; A first end of the seventh resistor is connected to the controller, and a second end of the seventh resistor is connected to a first end of the first switch; A first end of the eighth resistor is connected to the controller, and a second end of the eighth resistor is connected to a first end of the second switch; A first end of the ninth resistor is connected to the controller, and a second end of the ninth resistor is connected to a first end of the third switch.

7. The power supply reverse connection protection circuit according to claim 1, characterized in that: Also includes: Tenth resistor; A first end of the tenth resistor is connected to the controller, and a second end of the tenth resistor is connected to the chip selection communication interface.

8. The power reverse connection protection circuit according to claim 1, characterized in that: The switch unit includes a high-side driver chip with a communication function.

9. A vehicle body controller, characterized in that: The invention comprises the power supply reverse connection protection circuit as described in any one of claims 1 to 8.

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