Diagnostic protection circuit, electronic equipment and vehicle

Abstract

The utility model provides a diagnosis protection circuit, electronic equipment and a vehicle, and belongs to the technical field of power supply diagnosis. The switch unit is respectively connected with a power supply and a load to form a power supply loop; a first comparison unit and a second comparison unit, the first comparison unit being configured to conduct a grounding loop when the voltage output by the power supply is in an overvoltage range so as to lower the level input to the second comparison unit; the second comparison unit is configured to cut off the control loop when the level input by the second comparison unit is pulled down and the voltage output by the power supply is in an undervoltage range; wherein the voltage in the overvoltage range is not overlapped with the voltage in the undervoltage range; and the switch unit is configured to be in an off state when the control loop is cut off so as to cut off the power supply loop. Through the diagnosis protection circuit provided by the utility model, under-voltage and over-voltage diagnosis can be carried out on the voltage output by the power supply.

Description

Technical Field

[0001] The utility model belongs to the technical field of power supply diagnosis, and in particular relates to a diagnostic protection circuit, electronic equipment and a vehicle. Background Art

[0002] To ensure that functional safety products remain safe when the power supply voltage is abnormal, two power supply diagnostic methods are generally used. The first is to use a PMIC (Power Management Integrated Circuit) or SBC (System Base Chip) with integrated overvoltage and undervoltage detection functions, and implement safety control during voltage anomalies through MCU (Microcontroller Unit) configuration, but the first method is too expensive. The second is to use a lower-cost LDO (Low Dropout Regulator) chip and rely on the MCU's LVD (Low Voltage Detector) to monitor the voltage, but the second method cannot detect overvoltage. Utility Model Content

[0003] In view of the above problems, embodiments of the present application provide a diagnostic protection circuit, an electronic device, and a vehicle to overcome the above problems or at least partially solve the above problems.

[0004] In a first aspect of an embodiment of the present application, a diagnostic protection circuit is provided, comprising:

[0005] power supply;

[0006] A switch unit is connected to the power supply and the load respectively to form a power supply circuit;

[0007] a first comparing unit and a second comparing unit, wherein the first comparing unit, the power supply, and the ground terminal form a ground loop, and the second comparing unit is connected to the power supply to form a control loop, wherein the output terminal of the first comparing unit is connected to the input terminal of the second comparing unit, and the output terminal of the second comparing unit is also connected to the switch unit;

[0008] The first comparing unit is configured to turn on the ground loop when the voltage output by the power supply is in an overvoltage range, so as to lower the level input to the second comparing unit;

[0009] The second comparison unit is configured to cut off the control loop when the level of the second comparison unit input is pulled low and the voltage output by the power supply is in an undervoltage range; wherein the voltage in the overvoltage range does not overlap with the voltage in the undervoltage range;

[0010] The switch unit is configured to be in an off state when the control circuit is cut off, so as to cut off the power supply circuit.

[0011] Further, the first comparison unit includes a first comparator, and the second comparison unit includes a second comparator;

[0012] The first comparator and the second comparator each include a first terminal, a second terminal and a third terminal; wherein the conduction state between the second terminal and the third terminal is controlled by an input signal of the first terminal;

[0013] Wherein, the first terminal of the first comparator is connected to the output terminal of the power supply, and the third terminal of the first comparator is connected to the ground terminal to form the ground loop;

[0014] The second end of the second comparator is connected to the control end of the switch unit, and the third end of the second comparator is connected to the ground end to form the control loop; wherein the second end of the first comparator is also connected to the first end of the second comparator.

[0015] Furthermore, the first comparison unit further includes: a first voltage divider circuit; wherein the input end of the first voltage divider circuit is connected to the output end of the power supply, and the output end of the first voltage divider circuit is connected to the first end of the first comparator;

[0016] The first voltage divider circuit is configured to divide the voltage output by the power supply and transmit the divided first voltage to the first terminal of the first comparator;

[0017] The first comparator is configured to connect the second terminal of the first comparator to the third terminal of the first comparator to open the ground loop when the first voltage exceeds the first reference voltage;

[0018] The second comparator is configured to disconnect the second terminal of the second comparator from the third terminal of the second comparator when the ground loop is conductive, so as to cut off the control loop.

[0019] Furthermore, the first voltage divider circuit includes: a first voltage divider resistor and a second voltage divider resistor; wherein, the first end of the first voltage divider resistor is connected to the output end of the power supply, the second end of the first voltage divider resistor is respectively connected to the first end of the second voltage divider resistor and the input end of the first comparator, and the second end of the second voltage divider resistor is grounded.

[0020] Furthermore, the second comparison unit further includes a second voltage divider circuit, wherein the input end of the second voltage divider circuit is connected to the output end of the power supply, and the output end of the second voltage divider circuit is connected to the first end of the second comparator;

[0021] The second voltage divider circuit is configured to divide the voltage output by the power supply and transmit the divided second voltage to the first terminal of the second comparator;

[0022] The second comparator is configured to disconnect the second terminal of the second comparator from the third terminal of the second comparator when the second voltage is lower than the second reference voltage, so as to cut off the control loop.

[0023] Furthermore, the second voltage-divider circuit includes: a third voltage-divider resistor and a fourth voltage-divider resistor; wherein, the first end of the third voltage-divider resistor is connected to the output end of the power supply, the second end of the third voltage-divider resistor is respectively connected to the first end of the fourth voltage-divider resistor and the first end of the second comparator, and the second end of the fourth voltage-divider resistor is grounded.

[0024] Furthermore, it further comprises: a fifth voltage-dividing resistor and a sixth voltage-dividing resistor; wherein the first end of the fifth voltage-dividing resistor and the first end of the sixth voltage-dividing resistor are respectively connected to the output end of the second comparing unit;

[0025] The second end of the fifth voltage-dividing resistor is connected to the control end of the switch unit, and the second end of the sixth voltage-dividing resistor is connected to the output end of the power supply.

[0026] Furthermore, the switch unit includes any type of transistor, MOS tube and relay.

[0027] According to a second aspect of the embodiments of the present application, an electronic device is provided, which includes the diagnostic protection circuit described in the first aspect of the embodiments.

[0028] According to a third aspect of an embodiment of the present application, a vehicle is provided, which includes the electronic device described in the second aspect of the embodiment, or the diagnostic protection circuit described in the first aspect of the embodiment.

[0029] A diagnostic protection circuit provided by this embodiment includes: a power supply; a switch unit, connected to the power supply and the load, respectively, to form a power supply circuit; a first comparison unit and a second comparison unit, wherein the first comparison unit, the power supply, and the ground terminal form a ground circuit, and the second comparison unit is connected to the power supply to form a control circuit, wherein the output terminal of the first comparison unit is connected to the input terminal of the second comparison unit, and the output terminal of the second comparison unit is also connected to the switch unit;

[0030] The first comparison unit is configured to turn on the ground loop when the voltage output by the power supply is in the overvoltage range, so as to lower the level input to the second comparison unit; the second comparison unit is configured so that the level input to the second comparison unit is lowered, and to cut off the control loop when the voltage output by the power supply is in the undervoltage range; wherein the voltages in the overvoltage range and the undervoltage range do not overlap; the switch unit is configured to be in an off state when the control loop is cut off, so as to cut off the power supply loop between the power supply and the load.

[0031] The diagnostic circuit provided in this embodiment, when applied to power supply diagnosis, can provide overvoltage protection and undervoltage protection to the load through the first comparison unit and the second comparison unit in the event of power supply overvoltage and undervoltage.

[0032] Overvoltage protection: When the first comparison unit detects that the voltage output by the power supply is in the overvoltage range, the first comparison unit will turn on the ground loop and assist the second comparison unit to cut off the control loop, thereby cutting off the power supply loop between the power supply and the load. This can prevent the power supply from outputting excessively high voltage to the load through the power supply loop, thereby avoiding damage to the load due to excessive voltage.

[0033] Undervoltage protection: When the second comparison unit detects that the voltage output by the power supply is in the undervoltage range, the second comparison unit will cut off the control circuit, and then cut off the power supply circuit between the power supply and the load, which can prevent the power supply output from the low voltage from passing through the power supply circuit to the load, thereby ensuring that the load cannot work normally or is damaged due to the low voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0035] Figure 1 This is a module diagram of a diagnostic circuit provided in an embodiment of the present application;

[0036] Figure 2 1 is a schematic diagram of a circuit structure of a diagnostic circuit provided in an embodiment of the present application;

[0037] Figure 3 1 is a schematic diagram of an internal equivalent circuit structure of a comparator provided in an embodiment of the present application;

[0038] Reference numerals:

[0039] 100-power supply; 200-load; 300-first comparison unit; 400-second comparison unit; 301-first voltage divider circuit; 402-second voltage divider circuit; Q1-switch unit; GND-ground terminal; T1-first comparator; T2-second comparator; R1-first voltage divider resistor; R2-second voltage divider resistor; R3-third voltage divider resistor; R4-fourth voltage divider resistor; R5-fifth voltage divider resistor; R6-sixth voltage divider resistor. DETAILED DESCRIPTION

[0040] The exemplary embodiments of the present application will be described in more detail below in conjunction with the accompanying drawings in the embodiments of the present application. Although the accompanying drawings show exemplary embodiments of the present application, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0041] Reference Figure 1 , Figure 1 This is a module diagram of a diagnostic circuit provided by an embodiment of the present application, Figure 1 It can be seen that the diagnostic protection circuit includes:

[0042] Reference Figure 1 , Figure 1 This is a module diagram of a diagnostic circuit provided by an embodiment of the present application, Figure 1 It can be seen that the diagnostic protection circuit includes:

[0043] A power supply 100; a switch unit Q1 connected to the power supply 100 and the load 200, respectively, to form a power supply circuit; a first comparison unit 300 and a second comparison unit 400, wherein the first comparison unit 300, the power supply 100, and the ground terminal GND form a ground circuit, and the second comparison unit 400 is connected to the power supply 100 to form a control circuit, wherein the output terminal of the first comparison unit 300 is connected to the input terminal of the second comparison unit 400, and the output terminal of the second comparison unit 400 is also connected to the switch unit Q1; wherein the first comparison unit 300 is configured to open the ground circuit when the voltage output by the power supply 100 is in an overvoltage range, thereby lowering the voltage level input to the second comparison unit 400; the second comparison unit 400 is configured to lower the voltage level input to the second comparison unit 400, and to disconnect the control circuit when the voltage output by the power supply 100 is in an undervoltage range; wherein the voltages in the overvoltage range and the undervoltage range do not overlap; and the switch unit Q1 is configured to be in an off state when the control circuit is disconnected, thereby disconnecting the power supply circuit.

[0044] In this embodiment, the switch unit Q1 is connected to the power supply 100 and the load 200, respectively. The power supply circuit can be controlled by turning the switch unit Q1 on and off. The first comparison unit 300 is connected to the power supply 100 and the ground terminal GND to form a ground circuit. The ground circuit can be controlled by turning the first comparison unit 300 on and off. The second comparison unit 400 forms a control circuit with the power supply 100. The circuit can be controlled by turning the second comparison unit 400 on and off. Since the output of the first comparison unit 300 is connected to the input of the second comparison unit 400, the conduction state of the second comparison unit 400 can also be controlled by whether the ground circuit is conductive. Therefore, the switch unit Q1 is controlled by the conduction state of the second comparator T2 unit 400 in the control circuit. The conduction state of the control circuit can be controlled by either the output voltage of the power supply 100 being within an undervoltage range or the conduction state of the ground circuit. The conduction state of the ground circuit is controlled by whether the output voltage of the power supply 100 is within an overvoltage range.

[0045] The first comparison unit 300 can determine the voltage output by the power supply 100. Specifically, when it is determined that the voltage output by the power supply 100 is in the overvoltage range, the ground loop can be turned on, and a low-level signal can be input to the second comparison unit 400 through the output end of the first comparison unit 300 via the ground end GND in the ground loop, thereby lowering the level of the input end of the second comparison unit 400, so that the second comparison unit 400 cuts off the control loop, and then controls the switch unit Q1 to be disconnected, cutting off the power supply loop between the power supply 100 and the load 200, and stopping the power supply 100 from supplying power to the load 200. This can prevent the power supply 100 from outputting an excessively high voltage through the power supply loop to the load 200, thereby preventing the load 200 from being damaged by excessive voltage.

[0046] The second comparison unit 400 can also determine the voltage output by the power supply 100. Specifically, when it is determined that the voltage output by the power supply 100 is in the undervoltage range, the voltage output by the power supply 100 is too low, which will also lower the level of the input end of the second comparison unit 400, so that the second comparison unit 400 cuts off the control loop, and then controls the switch unit Q1 to be disconnected, cutting off the power supply circuit between the power supply 100 and the load 200, preventing the power supply 100 from outputting an excessively low voltage through the power supply circuit to the load 200, thereby ensuring that the load 200 cannot work normally or is damaged due to the excessively low voltage.

[0047] In addition, when the voltage output by the power supply 100 is within the normal range, that is, the voltage output by the power supply 100 is neither within the overvoltage range nor within the undervoltage range, the first comparison unit 300 is not conductive, that is, the grounding loop is not conductive, and a low-level signal will not be output to the second comparison unit 400, thereby lowering the level of the input end of the second comparison unit 400. At this time, the second comparison unit 400 is in the conductive state, the control loop is conductive, and the control end of the control switch unit Q1 is controlled to make the switch unit Q1 conductive, and the power supply circuit is also in the conductive state, and the power supply 100 continues to supply power to the load 200 through the power supply circuit.

[0048] In summary, when the voltage output by the power supply 100 is abnormal, that is, when it is in the overvoltage range or undervoltage range, it can immediately respond by cutting off the power supply circuit to prevent the abnormal voltage from supplying power to the load 200 and ensure the safety of the load 200. When the voltage output by the power supply 100 is within the normal range, the power supply circuit is maintained in the on state, and the power supply 100 continues to supply power to the load 200 through the power supply circuit.

[0049] In a specific embodiment, referring to Figure 2 , Figure 2 This is a schematic diagram of the circuit structure of a diagnostic circuit provided in an embodiment of the present application. Figure 2 It can be seen that the first comparison unit 300 includes a first comparator T1, and the second comparison unit 400 includes a second comparator T2; the first comparator T1 and the second comparator T2 each include a first end, a second end and a third end; wherein the conduction state between the second end and the third end is controlled by an input signal of the first end; wherein the first end of the first comparator T1 is connected to the output end of the power supply 100, and the third end of the first comparator T1 is connected to the ground end GND to form a ground loop; the second end of the second comparator T2 is connected to the control end of the switch unit Q1, and the third end of the second comparator T2 is connected to the ground end GND to form a control loop; wherein the second end of the first comparator T1 is also connected to the first end of the second comparator T2.

[0050] In this embodiment, the first comparison unit 300 includes a first comparator T1, and the second comparison unit 400 includes a second comparator T2. The first comparator T1 and the second comparator T2 each include a first terminal, a second terminal, and a third terminal, and the conduction state between the second terminals is controlled by an input signal at the first terminal. That is, the conduction principles of the first comparator T1 and the second comparator T2 may be consistent. The first terminal of the first comparator T1 is connected to the output terminal of the power supply 100, and the third terminal of the first comparator T1 is connected to the ground terminal GND to form a ground loop. When the second terminal of the first comparator T1 and the third terminal of the first comparator T1 are conductive, the ground loop is conductive. When the second terminal of the first comparator T1 and the third terminal of the first comparator T1 are not conductive, the ground loop is not conductive.

[0051] The second terminal of the first comparator T1 is connected to the first terminal of the second comparator T2;

[0052] The second end of the second comparator T2 is connected to the control end of the switch unit Q1, and the third end of the second comparator T2 is connected to the ground end GND to form a control loop. When the second end of the second comparator T2 and the third end of the first comparator T1 are conductive, the control loop is conductive. When the second end of the second comparator T2 and the third end of the first comparator T1 are not conductive, the control loop is not conductive.

[0053] Since the second terminal of the first comparator T1 is connected to the first terminal of the second comparator T2 , the conduction state of the control loop can be controlled by the signal output from the second terminal of the first comparator T1 .

[0054] For example, refer to Figure 3 , Figure 3 This is a schematic diagram of the internal equivalent circuit structure of a comparator provided in an embodiment of the present application. The first comparator T1 can be and the second comparator T2 can be Figure 3 The comparator in Figure 1 consists of a reference voltage op amp and an NPN transistor. When the voltage at the first input is greater than the reference voltage, the op amp's output voltage drives the PNP transistor into conduction, connecting the second and third terminals. Because the reference voltage is internally fixed, the principle of conduction between the first and second comparators T1 and T2 can be summarized as follows: the input signal at the first terminal controls the conduction and cutoff of the second and third terminals.

[0055] In a specific embodiment, referring to Figure 2 The first comparison unit 300 further includes: a first voltage divider circuit 301; wherein the input end of the first voltage divider circuit 301 is connected to the output end of the power supply 100, and the output end of the first voltage divider circuit 301 is connected to the first end of the first comparator T1; the first voltage divider circuit 301 is configured to divide the voltage output by the power supply 100 and transmit the divided first voltage to the first end of the first comparator T1; the first comparator T1 is configured to connect the second end of the first comparator T1 and the third end of the first comparator T1 to conduct the ground loop when the first voltage exceeds the first reference voltage; the second comparator T2 is configured to disconnect the second end of the second comparator T2 and the third end of the second comparator T2 to cut off the control loop when the ground loop is conducted.

[0056] In this embodiment, by Figure 2 In the connection mode between the first voltage divider circuit 301, the first comparator T1, the power supply 100, and the second comparator T2, the first voltage divider circuit 301 divides the voltage output by the power supply 100 when the power supply 100 outputs a voltage, and transmits the divided first voltage to the first end of the first comparator T1, combined with Figure 3 When the first terminal of the first comparator T1 receives the first voltage, it compares the first voltage with the first reference voltage carried by the first comparator T1. By comparing the first voltage with the first reference voltage, it is determined whether the voltage output by the power supply 100 is within the overvoltage range. If the first voltage is greater than the first reference voltage, the voltage output by the power supply 100 is within the overvoltage range, and the connection between the second terminal of the first comparator T1 and the third terminal of the first comparator T1 is connected to open the ground loop.

[0057] Then, when the ground loop is turned on, the second comparator T2 outputs a low-level signal to the first terminal of the second comparator T2 through the second terminal of the first comparator T1, thereby causing the second comparator T2 to disconnect the second terminal of the second comparator T2 from the third terminal of the second comparator T2, thereby cutting off the control loop.

[0058] In a specific embodiment, referring to Figure 2 The first voltage divider circuit 301 includes: a first voltage divider resistor R1 and a second voltage divider resistor R2; wherein, the first end of the first voltage divider resistor R1 is connected to the output end of the power supply 100, the second end of the first voltage divider resistor R1 is respectively connected to the first end of the second voltage divider resistor R2 and the input end of the first comparator T1, and the second end of the second voltage divider resistor R2 is grounded.

[0059] In this embodiment, the first voltage divider circuit 301 includes a first voltage divider resistor R1 and a second voltage divider resistor R2. Figure 2 The connection method of the first voltage-dividing resistor R1 and the second voltage-dividing resistor R2 can divide the voltage output by the power supply 100, and then input the first voltage obtained after the voltage division into the first end of the first comparator T1, which can prevent the voltage output by the power supply 100 from being too high, causing damage to the first comparator T1. In addition, the first reference voltage in this embodiment can be set by the first voltage-dividing resistor R1 and the second voltage-dividing resistor R2, specifically: first reference voltage = (1 + first voltage-dividing resistor R1 / second voltage-dividing resistor R2) * first voltage.

[0060] In a specific embodiment, referring to Figure 2 The second comparison unit 400 also includes a second voltage divider circuit 401, wherein the input end of the second voltage divider circuit 401 is connected to the output end of the power supply 100, and the output end of the second voltage divider circuit 401 is connected to the first end of the second comparator T2; the second voltage divider circuit 401 is configured to divide the voltage output by the power supply 100 and transmit the divided second voltage to the first end of the second comparator T2; the second comparator T2 is configured to disconnect the second end of the second comparator T2 and the third end of the second comparator T2 when the second voltage is lower than the second reference voltage, so as to cut off the control loop.

[0061] In this embodiment, by Figure 2 The connection mode between the second voltage divider circuit 401, the first comparator T1, the second comparator T2, the switch unit Q1, and the power supply 100 is that when the power supply 100 outputs a voltage, the second voltage divider circuit 401 divides the voltage output by the power supply 100 and transmits the divided second voltage to the first end of the first comparator T1. Figure 3 When the first terminal of the second comparator T2 receives the second voltage, it compares the second voltage with the second reference voltage carried by the first comparator T1. By comparing the second voltage with the second reference voltage, it is determined whether the voltage output by the power supply 100 is within the undervoltage range. If the second voltage is less than the second reference voltage, the voltage output by the power supply 100 is within the undervoltage range, and the connection between the second terminal of the second comparator T2 and the third terminal of the second comparator T2 is disconnected to cut off the control loop.

[0062] In a specific embodiment, referring to Figure 2 The second voltage-dividing circuit 401 includes: a third voltage-dividing resistor R3 and a fourth voltage-dividing resistor R4; wherein, the first end of the third voltage-dividing resistor R3 is connected to the output end of the power supply 100, the second end of the third voltage-dividing resistor R3 is respectively connected to the first end of the fourth voltage-dividing resistor R4 and the first end of the second comparator T2, and the second end of the fourth voltage-dividing resistor R4 is grounded.

[0063] In this embodiment, the second voltage divider circuit 401 includes: a third voltage divider resistor R3 and a fourth voltage divider resistor R4. Figure 2 The connection method of the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4 can divide the voltage output by the power supply 100, and then output the second voltage obtained by the voltage division to the second comparator T2, which can prevent the voltage output by the power supply 100 from being too high, causing damage to the second comparator T2. In addition, the second reference voltage in this embodiment can be set by the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4, specifically: second reference voltage = (1 + third voltage-dividing resistor R3 / fourth voltage-dividing resistor R4) * second voltage. In this embodiment, the first reference voltage and the second reference voltage can be equal or unequal, and can be specifically determined by the resistance values ​​of the first voltage-dividing resistor R1, the second voltage-dividing resistor R2, the third voltage-dividing resistor R3, and the fourth voltage-dividing resistor R4, which is not limited in this embodiment.

[0064] In a specific embodiment, referring to Figure 2 The acquisition circuit further includes: a fifth voltage-dividing resistor R5 and a sixth voltage-dividing resistor R6; wherein the first end of the fifth voltage-dividing resistor R5 and the first end of the sixth voltage-dividing resistor R6 are respectively connected to the output end of the second comparison unit 400; the second end of the fifth voltage-dividing resistor R5 is connected to the control end of the switch unit Q1, and the second end of the sixth voltage-dividing resistor R6 is connected to the output end of the power supply 100.

[0065] In this embodiment, the acquisition circuit further includes a fifth voltage-dividing resistor R5 and a sixth voltage-dividing resistor R6. Figure 2 The connection method of the fifth voltage-dividing resistor R5 and the sixth voltage-dividing resistor R6 allows the voltage output by the power supply 100 to be divided by the fifth voltage-dividing resistor R5 and the sixth voltage-dividing resistor R6 to generate a control voltage acting on the control end of the switch unit Q1, thereby controlling the conduction and shutoff of the switch unit Q1. Since the second end of the fifth voltage-dividing resistor R5 is connected to the control end of the switch, a control voltage can be generated at the control end of the switch unit Q1 only when the second comparison unit 400 is turned on. If the second comparison unit 400 is turned off, the control loop is disconnected, and the switch unit Q1 cannot be turned on by the voltage output by the power supply 100, and the power supply loop is also disconnected.

[0066] In a specific embodiment, the switch unit Q1 includes any one of a transistor, a MOS transistor and a relay.

[0067] In this embodiment, the switch unit Q1 may include any type of transistor, MOS transistor and relay. When the switch unit Q1 is a transistor, the control end of the switch unit Q1 may be the base of the transistor, and the conduction and shutoff of the transistor may be controlled by outputting an appropriate voltage to the base; when the switch unit Q1 is a MOS transistor, the control end of the switch unit Q1 may be the gate of the MOS transistor, and the conduction and shutoff of the MOS transistor may be controlled by outputting an appropriate voltage to the gate; when the switch unit Q1 is a relay, the control end of the switch unit Q1 may be the connection end of the electromagnetic coil of the relay, and the connection and shutoff of the relay may be controlled by applying a current to the connection end.

[0068] For example, the following will refer to Figure 2 The diagnostic circuit provided in this embodiment is described in detail, with the switch unit Q1 being a PNP transistor, the first comparator T1 and the second comparator T2 being TL431 adjustable precision reference voltage sources.

[0069] Reference Figure 2The first voltage-dividing resistor R1 and the second voltage-dividing resistor R2 form a first voltage-dividing circuit 301, which divides the voltage output by the power supply 100. The first voltage obtained after voltage division is: U1 = R2 / (R1+R2)*Vout (voltage output by the power supply), and then the first voltage is output to the first end of the first comparator T1. The third end of the first comparator T1 is connected to the ground end GND. The second end of the first comparator T1 is connected to the third voltage-dividing resistor R3, the fourth voltage-dividing resistor R4 and the first end of the second comparator T2. The second voltage-dividing circuit 401 composed of the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4 divides the voltage output by the power supply 100. The second voltage obtained after voltage division is: U2 = R3 / (R3+R4)*Vout.

[0070] The second end of the second comparator T2 is connected to the fifth voltage-dividing resistor R5 and the sixth voltage-dividing resistor R6, respectively. The fifth voltage-dividing resistor R5 is also connected to the base of the switching unit Q1 and can serve as a bias resistor for the switching unit Q1. The emitter of the switching unit Q1 is connected to the output end of the power supply 100, and the collector is connected to the load 200, providing the load 200 with the voltage output by the power supply 100.

[0071] exist Figure 2 In the circuit, the first comparator T1 functions as an overvoltage judge and controls the voltage of the first input terminal of the second comparator T2. When the voltage output by the power supply 100 is within a set range, the first voltage of the first terminal of the first comparator T1 is lower than the internal reference voltage (first reference voltage), the second terminal and the third terminal of the first comparator T1 are not conductive, so that the voltage of the first terminal of the second comparator T2 is high, and finally the switch unit Q1 is controlled to be turned on; when the voltage output by the power supply 100 is within an overvoltage range, that is, exceeds a set threshold value, the first voltage of the first terminal of the first comparator T1 is higher than the internal reference voltage (first reference voltage), the second terminal and the third terminal of the first comparator T1 are conductive, so that the voltage of the first terminal of the second comparator T2 becomes low, and finally the switch unit Q1 is controlled to be turned off.

[0072] The second comparator T2 is used for undervoltage detection and driving the switch unit Q1. When the voltage output by the power supply 100 is within a set range, the second voltage at the first terminal of the second comparator T2 is higher than the internal reference voltage (the second reference voltage), and the second terminal and the third terminal of the second comparator T2 are conductive, thereby turning on the switch unit Q1. When the voltage output by the power supply 100 is within the undervoltage range, the second voltage at the first terminal of the second comparator T2 is lower than the internal reference voltage (the second reference voltage), and the second terminal and the third terminal of the second comparator T2 are not conductive, thereby turning off the switch unit Q1.

[0073] Furthermore, to ensure good response time, the first-terminal input current of the first comparator T1 and the second comparator T2 must be greater than 4uA, and IKA must be greater than 1mA. Therefore, the resistance values ​​of the first, second, third, fourth, and fifth voltage-divider resistors R1, R2, R3, R4, and R5 should be minimal; recommended values ​​are less than 10kΩ. Voltage accuracy is primarily determined by the accuracy of the first, second, third, fourth, and fifth voltage-divider resistors R1, R2, R3, R4, and R5, as well as the accuracy of the TL431's internal reference voltage. The TL431 offers several accuracy options: 0.5%, 1%, and 2%. If a 0.5% accuracy option is selected and the resistor thickness is 0.1%, the cumulative accuracy is 0.6%. If the power supply output voltage is 5V, the threshold setting accuracy is approximately 0.03V, which is also quite high.

[0074] In summary, this embodiment utilizes only two TL431s, a PNP transistor, and six voltage-divider resistors. This embodiment offers a simple circuit structure, extremely low cost, and ease of implementation, while also achieving a high accuracy of 0.6%. From a functional safety perspective, this diagnostic approach, which operates from the output of power supply 100, provides high diagnostic coverage.

[0075] This embodiment further provides an electronic device, which includes the diagnostic protection circuit of this embodiment.

[0076] This embodiment further provides a vehicle, which includes the electronic device of this embodiment or the diagnostic protection circuit of this embodiment.

[0077] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0078] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0079] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "includes," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of additional identical elements in the process, article, or terminal device that includes the element.

[0080] The diagnostic protection circuit, electronic device and vehicle provided by the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A diagnostic protection circuit, characterized in that: include: power supply; A switch unit is connected to the power supply and the load respectively to form a power supply circuit; a first comparing unit and a second comparing unit, wherein the first comparing unit, the power supply, and the ground terminal form a ground loop, and the second comparing unit is connected to the power supply to form a control loop, wherein the output terminal of the first comparing unit is connected to the input terminal of the second comparing unit, and the output terminal of the second comparing unit is also connected to the switch unit; The first comparing unit is configured to turn on the ground loop when the voltage output by the power supply is in an overvoltage range, so as to lower the level input to the second comparing unit; The second comparison unit is configured to cut off the control loop when the level of the second comparison unit input is pulled low and the voltage output by the power supply is in an undervoltage range; wherein the voltage in the overvoltage range does not overlap with the voltage in the undervoltage range; The switch unit is configured to be in an off state when the control circuit is cut off, so as to cut off the power supply circuit.

2. The diagnostic protection circuit according to claim 1, characterized in that: The first comparison unit includes a first comparator, and the second comparison unit includes a second comparator; The first comparator and the second comparator each include a first terminal, a second terminal and a third terminal; wherein the conduction state between the second terminal and the third terminal is controlled by an input signal of the first terminal; Wherein, the first terminal of the first comparator is connected to the output terminal of the power supply, and the third terminal of the first comparator is connected to the ground terminal to form the ground loop; The second end of the second comparator is connected to the control end of the switch unit, and the third end of the second comparator is connected to the ground end to form the control loop; wherein the second end of the first comparator is also connected to the first end of the second comparator.

3. The diagnostic protection circuit according to claim 2, characterized in that: The first comparison unit further includes: a first voltage divider circuit; wherein the input end of the first voltage divider circuit is connected to the output end of the power supply, and the output end of the first voltage divider circuit is connected to the first end of the first comparator; The first voltage divider circuit is configured to divide the voltage output by the power supply and transmit the divided first voltage to the first terminal of the first comparator; The first comparator is configured to connect the second terminal of the first comparator to the third terminal of the first comparator to open the ground loop when the first voltage exceeds a first reference voltage; The second comparator is configured to disconnect the second terminal of the second comparator from the third terminal of the second comparator when the ground loop is conductive, so as to cut off the control loop.

4. The diagnostic protection circuit according to claim 3, characterized in that: The first voltage divider circuit includes: a first voltage divider resistor and a second voltage divider resistor; wherein, the first end of the first voltage divider resistor is connected to the output end of the power supply, the second end of the first voltage divider resistor is respectively connected to the first end of the second voltage divider resistor and the input end of the first comparator, and the second end of the second voltage divider resistor is grounded.

5. The diagnostic protection circuit according to any one of claims 2 to 4, characterized in that: The second comparison unit further includes a second voltage divider circuit, wherein the input end of the second voltage divider circuit is connected to the output end of the power supply, and the output end of the second voltage divider circuit is connected to the first end of the second comparator; The second voltage divider circuit is configured to divide the voltage output by the power supply and transmit the divided second voltage to the first terminal of the second comparator; The second comparator is configured to disconnect the second terminal of the second comparator from the third terminal of the second comparator when the second voltage is lower than a second reference voltage, so as to cut off the control loop.

6. The diagnostic protection circuit according to claim 5, characterized in that: The second voltage-dividing circuit includes: a third voltage-dividing resistor and a fourth voltage-dividing resistor; wherein, the first end of the third voltage-dividing resistor is connected to the output end of the power supply, the second end of the third voltage-dividing resistor is respectively connected to the first end of the fourth voltage-dividing resistor and the first end of the second comparator, and the second end of the fourth voltage-dividing resistor is grounded.

7. The diagnostic protection circuit according to claim 1, characterized in that: Also includes: a fifth voltage-dividing resistor and a sixth voltage-dividing resistor; wherein the first end of the fifth voltage-dividing resistor and the first end of the sixth voltage-dividing resistor are respectively connected to the output end of the second comparing unit; The second end of the fifth voltage-dividing resistor is connected to the control end of the switch unit, and the second end of the sixth voltage-dividing resistor is connected to the output end of the power supply.

8. The diagnostic protection circuit according to claim 1, characterized in that: The switch unit includes any type of transistor, MOS tube and relay.

9. An electronic device, characterized in that: The electronic device comprises the diagnostic protection circuit according to any one of claims 1 to 8.

10. A vehicle, characterized in that: The vehicle includes the electronic device according to claim 9, or the diagnostic protection circuit according to any one of claims 1 to 8.

Images