Switch identification circuit and electric device

Abstract

This application discloses a switch identification circuit, including an identification unit, a detection unit, a control unit, a connection unit, a first connection terminal, and a second connection terminal. The identification unit is electrically connected to the first connection terminal and the second connection terminal, and is used to provide a conductive loop when the first connection terminal and the second connection terminal are short-circuited. The detection unit is electrically connected to the first connection terminal and the second connection terminal, detects the voltage between the first connection terminal and the second connection terminal, and outputs a first detection signal and a second detection signal. The connection unit is electrically connected to a power supply device for providing a driving voltage to the first connection terminal and the second connection terminal. The control unit is used to determine whether the first connection terminal is short-circuited with the second connection terminal based on the received first detection signal and second detection signal. If the two connection terminals are short-circuited, the control unit outputs a connection enable signal to the connection unit, and the connection unit controls the power supply device to stop providing the driving voltage. This application also discloses an electric device including the aforementioned switch identification circuit.

Description

Technical Field

[0001] This application relates to the field of circuits, and more particularly to a switch identification circuit and an electric device. Background Technology

[0002] When a car starts, the power supply sends a power signal to the starter motor, enabling it to ignite and start the engine. During this process, a switch identification circuit is needed to recognize the connection status of the load devices to ensure a stable and safe start for the car engine.

[0003] Currently, most switch recognition circuits use transistors or optocouplers to identify the electrical signals of the load device to determine whether the connection status of the load device meets the requirements for vehicle startup. However, since transistor or optocoupler recognition circuits require a minimum turn-on voltage value to allow charge to pass through, this type of switch recognition circuit cannot identify short circuits, reducing the safety of the vehicle during startup. Summary of the Invention

[0004] To address the aforementioned problems, one embodiment of this application provides a switch identification circuit, including an identification unit, a detection unit, a control unit, a connection unit, a first connection terminal, and a second connection terminal. The identification unit is electrically connected to the first connection terminal and the second connection terminal, providing a conductive loop when the first connection terminal and the second connection terminal are short-circuited. The detection unit is electrically connected to the first connection terminal and the second connection terminal, detecting the voltages at the first connection terminal and the second connection terminal respectively, and outputting a first detection signal and a second detection signal accordingly. The control unit is electrically connected to the detection unit and the connection unit, receiving the first detection signal and the second detection signal, and determining whether the first connection terminal is short-circuited with the second connection terminal based on the first detection signal and the second detection signal. The connection unit is electrically connected to a power supply device, which provides a driving voltage to the first connection terminal and the second connection terminal. If the first connection terminal and the second connection terminal are short-circuited, the control unit outputs a connection enable signal to the connection unit, and the connection unit controls the power supply device to stop providing the driving voltage.

[0005] One embodiment of this application provides an electric device, including the aforementioned switch identification circuit, power supply device, and load device. The power supply device is electrically connected to the load device and is used to drive the load device to start when the power supply device and the load device form a conductive circuit. The switch identification circuit is electrically connected to the power supply device and is used to enable the power supply device to provide a driving voltage to a first connection terminal and a second connection terminal when the connection unit in the switch identification circuit is controlled by a connection enable signal to provide the driving voltage to the first connection terminal and the second connection terminal, thereby enabling the power supply device and the load device to form a conductive circuit.

[0006] Compared with existing technologies, the switch identification circuit disclosed in this application detects the voltage at the first and second connection terminals, enabling it to control the power supply device to stop providing drive voltage to the load device when the first and second identification terminals are directly or indirectly short-circuited. Therefore, the switch identification circuit provided in this application can accurately identify the dangerous short-circuit condition between the first and second connection terminals compared to detection methods using transistors or optocouplers, thus providing higher safety for the load connected to the first and second connection terminals during startup. Attached Figure Description

[0007] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0008] Figure 1 This is a schematic diagram of the structure of a switch recognition circuit disclosed in an embodiment of this application;

[0009] Figure 2 for Figure 1 A schematic diagram of the specific circuit structure of the identification unit in the switch identification circuit shown;

[0010] Figure 3 for Figure 1 The schematic diagram shows the specific circuit structure of the second detection unit in the switch recognition circuit shown.

[0011] Figure 4 for Figure 1 The diagram shows the structural structure of the connection unit in the switch recognition circuit. Detailed Implementation

[0012] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0013] When a car starts, the battery supplies power to the starter motor, enabling it to ignite and start the engine. If the battery malfunctions or its connection to the starter motor fails, the starter motor will not start properly, reducing the safety of the car during the starting process.

[0014] Therefore, it is necessary to test the battery and the connection between the battery and the starter motor before starting the car to ensure greater safety during the starting process.

[0015] This application discloses a switch identification circuit for detecting the power supply device, including the battery, and the connection method between the power supply device and the load device, including the starter motor, before starting the car. This enables the load device to start when both the power supply device and the connection method between the power supply device and the load device meet the starting requirements.

[0016] Please see Figure 1 This is a schematic diagram of a switch identification circuit disclosed in an embodiment of this application. Figure 1 As shown, the switch identification circuit 100 includes a control unit 101, an identification unit 102, a battery unit 103, a detection unit 104, and a connection unit 105.

[0017] The control unit 101 is electrically connected to the identification unit 102 and is used to output an identification enable signal to the identification unit 102 so that the identification unit 102 enters the identification state under the control of the first potential in the identification enable signal, and exits the identification state under the control of the second potential in the identification enable signal.

[0018] The identification unit 102 is electrically connected to the first connection terminal N1 and the second connection terminal N2. It receives the voltage at the first connection terminal N1 as a first identification signal and receives the voltage at the second connection terminal N2 as a second identification signal, and transmits both the first and second identification signals to the detection unit 104. The first connection terminal N1 is electrically connected to the positive terminal of the power supply device 200 and the load device 300, and the second connection terminal is electrically connected to the negative terminal of the power supply device 200 and the load device 300. The power supply device 200 is used to drive the load device 300 to start operation.

[0019] The detection unit 104 includes a first detection unit 1041 and a second detection unit 1042.

[0020] The first detection unit 1041 is electrically connected to the control unit 101 and is used to receive the first identification signal output by the identification unit 102, and output the first detection signal to the control unit 101 after performing voltage division processing on the first identification signal. The voltage division processing is to convert the first identification signal into a first detection signal that conforms to the voltage division relationship in the first detection unit 1041. The voltage division relationship is determined by the resistance value and connection relationship of the resistor in the first detection unit 1041.

[0021] The second detection unit 1042 is electrically connected to the control unit 101 and is used to receive the second identification signal output by the identification unit 102, and output the second detection signal to the control unit 101 after performing voltage division processing on the second identification signal.

[0022] The control unit 101 is used to receive the first detection signal and the second detection signal, perform a difference operation on the first detection signal and the second detection signal to obtain a detection difference, compare the detection difference with the detection threshold, and output a connection enable signal to the second detection unit 1042 and the connection unit 105.

[0023] Optionally, the control unit 101 can also calculate the value of the first identification signal based on the voltage division relationship between the first detection signal and the first identification signal, and similarly obtain the value of the second identification signal. The control unit 101 then performs a difference operation on the calculated first identification signal and the second identification signal, and uses the result of the difference operation as the identification difference. After comparing the identification difference with the identification threshold, the control unit 101 outputs a connection enable signal to the second detection unit 1042 and the connection unit 105.

[0024] In this embodiment of the application, if the detection difference is greater than the detection threshold, the control unit 101 outputs the second potential in the recognition enable signal to make the recognition unit 102 exit the recognition state, and outputs the first potential in the connection enable signal to the second detection unit 1042 and the connection unit 105, so that the second detection unit 1042 enters the current detection state and the connection unit 105 enters the conduction state.

[0025] In this embodiment, if the detection difference is less than the detection threshold, the control unit 101 continues to output the first potential in the recognition enable signal to keep the recognition unit 102 in the recognition state, and outputs the second potential in the connection enable signal to the second detection unit 1042 and the connection unit 105, so that the second detection unit 1042 continues to be in the voltage detection state and the connection unit 105 enters the cut-off state.

[0026] Specifically, if the detection difference is zero, the voltage at the first identification terminal S1 is the same as the voltage at the second identification terminal S2, indicating that the first identification terminal S1 and the second identification terminal S2 are short-circuited. The control unit 101 outputs a second potential of the connection enable signal to the connection unit 105, and the connection unit 105 is in the off state. If the detection difference is negative, the voltage at the first identification terminal S1 is less than the voltage at the second identification terminal S2, indicating that the first identification terminal S1 is connected to the second connection terminal N2 and the second identification terminal S2 is connected to the first connection terminal N1. The control unit 101 outputs a second potential of the connection enable signal to the connection unit 105, and the connection unit 105 is in the off state. If the detection difference is positive and less than the detection threshold, it indicates that the power supply device 200 is in a low-voltage state. The control unit 101 outputs a second potential of the connection enable signal to the connection unit 105, and the connection unit 105 is in the off state.

[0027] The connection unit 105 is electrically connected to the control unit 101 and is used to receive the connection enable signal output by the control unit 101. It enters the on state under the action of the first potential in the connection enable signal and enters the off state under the action of the second potential in the connection enable signal.

[0028] The connection unit 105 is also electrically connected to the power supply device 200. When it is in the conducting state, the power supply device 200, the load device 300, and the connection unit 105 form a conductive circuit, and the power supply device 200 can output a power signal to the load device 300 to enable the load device 300 to start. The connection unit 105 is also used to prevent the power supply device 200, the load device 300, and the connection unit 105 from forming a conductive circuit when it is in the cut-off state, so that the load device 300 cannot start.

[0029] The battery unit 103 is electrically connected to the first connection terminal N1 to maintain the voltage at the first connection terminal N1. It can maintain the voltage difference between the first connection terminal N1 and the second connection terminal N2 even when the power supply device 200 is missing, so as to cooperate with the identification unit 102 to complete the identification of the voltage at the first connection terminal N1 and the second connection terminal N2 when the identification unit is in the identification state.

[0030] The connection unit 105 is also electrically connected to the battery unit 103. When the battery unit 103, the load device 300, and the connection unit 105 form a conductive circuit in the circuit when the circuit is in the conducting state and the power supply device 200 is missing, the battery unit 103 can output battery power to the load device 300 so that the load device 300 can start up.

[0031] The connection unit 105 is also electrically connected to the second detection unit 1042. When the control unit 101 outputs the first potential in the connection enable signal, the second detection unit 1042 is put into the current detection state, and when the connection unit 105 is put into the conduction state, the current signal in the conductive circuit formed by the power supply device 200, the load device 300 and the connection unit 105 is output to the second detection unit 1042, and the second detection unit 1042 outputs the current signal to the control unit 101.

[0032] The control unit 101 is also used to receive the current signal output by the second detection unit 1042, and after the current signal exceeds the current threshold, adjust the connection enable signal output to the second detection unit 1042 and the connection unit 105 from the first potential to the second potential, and the connection unit 105 enters the cut-off state so that the power supply device 200, the load device 300 and the connection unit 105 cannot form a conductive circuit, and the load device 300 stops working.

[0033] In this embodiment, the switch identification circuit 100 can identify the state of the power supply device 200 and the connection state between the power supply device 200 and the load device 300 through the cooperation of the identification unit 102 and the battery unit 103. The control unit 101 will output the first potential in the connection enable signal to the connection unit 105 when the state of the power supply device 200 and the connection state between the power supply device 200 and the load device 300 meet the start-up requirements, so that the connection unit 105 enters the conduction state. After that, the power supply device 200 electrically connected to the connection unit 105 can form a conductive circuit with the load device 300 and output a power signal to the load device 300 so that the load device 300 can start up.

[0034] In this embodiment, the power supply device 200 is in three states: standard voltage, low voltage, and missing. The connection state between the power supply device 200 and the load device 300 is in three states: positive connection, reverse connection, and short connection. The startup requirement refers to the connection state being positive and the power supply device 200 being in the standard voltage or missing state.

[0035] In this embodiment, the control unit 101 may be a microcontroller unit (MCU), a field programmable gate array (FPGA), or other integrated circuits capable of controlling subsequent units. This embodiment does not specifically limit this.

[0036] Please see Figure 2 , it is Figure 1 The diagram shows the specific circuit structure of the identification unit in the switch identification circuit shown. Figure 2As shown, the identification unit 102 includes a first identification terminal S1, a second identification terminal S2, and a first transistor Q1.

[0037] The first identification terminal S1 is electrically connected to the first connection terminal N1, and the second identification terminal S2 is electrically connected to the second connection terminal N2. The power supply device 200 and the load device 300 are connected in parallel between the first connection terminal N1 and the second connection terminal N2.

[0038] The first detection unit 1041 is electrically connected to the first identification terminal S1 and is used to receive the voltage signal at the first identification terminal S1 as the first identification signal.

[0039] The second detection unit 1042 is electrically connected to the second identification terminal S2 and is used to receive the voltage signal at the second identification terminal S2 as the second identification signal.

[0040] The first identification terminal S1 is also electrically connected to the battery unit 103 to receive the identification voltage signal output by the battery unit 103, so that there is still a potential difference between the first identification terminal S1 and the second identification terminal S2 when the power supply device 200 is missing in the circuit.

[0041] The first resistor R1 is electrically connected between the first identification terminal S1 and the second identification terminal S2. The resistance value of the first resistor R1 is between 100 and 200 kilohms, so that the current flowing through the first resistor R1 is extremely small, which is equivalent to an open circuit.

[0042] The drain of the first transistor Q1 is electrically connected to the second identification terminal S2 through the second resistor R2, the source of the first transistor Q1 is electrically connected to the ground terminal GND, the gate of the first transistor Q1 is electrically connected to the identification enable signal output terminal of the control unit 101 (not shown) through the third resistor R3, and the gate of the first transistor Q1 is also electrically connected to the ground terminal GND through the fourth resistor R4.

[0043] Furthermore, the resistance value of the third resistor R3 is much smaller than that of the fourth resistor R4. That is, if the voltage value of the first potential of the recognition enable signal output by the control unit 101 is 5V, the voltage value input to the gate of the first transistor Q1 after voltage division by the fourth resistor R4 is only slightly less than 5V, which does not affect the conduction of the first transistor Q1. Moreover, when the recognition enable signal switches from the first potential to the second potential, the residual charge at the gate of the first transistor Q1 can be pulled down through the ground terminal GND of the fourth resistor R4. Compared with waiting for the residual charge to be naturally exhausted, the speed at which the first transistor Q1 enters the cutoff state can be improved.

[0044] In this embodiment, the first transistor Q1 is turned on by the first potential in the recognition enable signal output by the control unit 101, and the recognition unit 102 enters the recognition state. That is, after the first transistor Q1 is turned on, the first recognition terminal S1, the second recognition terminal S2, the second resistor R2, the first transistor Q1, and the ground terminal GND form a conductive circuit. The first detection unit 1041 and the second detection unit 1042 can then receive potential signals at the first recognition terminal S1 and the second recognition terminal S2. After that, the control unit 101 can then determine the state of the power supply device 200 and the connection state between the two recognition terminals and the two connection terminals based on the potential signals at these two locations.

[0045] In this embodiment, the power supply device 200 is in three states: standard voltage, low voltage, and missing. The connection states of the two identification terminals and the two connection terminals are in three states: positive connection, reverse connection, and short circuit.

[0046] Furthermore, the "positive connection" refers to the first identification terminal S1 being connected to the first connection terminal N1 and the second identification terminal S2 being connected to the second connection terminal N2. When the power supply device 200 is not missing, the voltage difference between the first identification terminal S1 and the second identification terminal S2 indicates whether the voltage value in the power supply device 200 is at standard voltage or low voltage. That is, if the voltage difference is lower than the voltage threshold, it is in the positive connection low voltage state; if the voltage difference is higher than the voltage threshold, it is in the positive connection standard voltage state. When the power supply device 200 is missing, the load device 300 is equivalent to a resistor connected between the first identification terminal S1 and the second identification terminal S2, which divides the voltage with the second resistor R2. At this time, it is in the positive connection no power supply state. However, due to the identification voltage output by the battery unit 103, the voltage difference between the first identification terminal S1 and the second identification terminal S2 can still meet the requirements of the control unit 101, thus enabling the connection unit 105 to enter the conduction state.

[0047] Furthermore, the reverse connection refers to the first identification terminal S1 being connected to the second connection terminal N1, and the second identification terminal being connected to the first connection terminal N1. When the power supply device 200 is not missing, regardless of whether the power supply device is in a standard voltage or low voltage state, the voltage at the second identification terminal S2 is significantly greater than the voltage at the first identification terminal S1. However, when the power supply device 200 is missing, the load device 300 acts as a resistor connected between the first identification terminal S1 and the second identification terminal S2, making the voltages at both the first identification terminal S1 and the second identification terminal S2 the same, thus creating a short circuit.

[0048] Furthermore, the short circuit refers to the first identification terminal S1 being directly connected to the second identification terminal S2, so that the voltages at both locations are the same and thus they are in another short circuit state.

[0049] Based on the above description of the power supply device 200's status and the connection status of the two identification terminals and the two connection terminals, the switch identification circuit 200, through the detection of the voltage values ​​at the first identification terminal S1 and the second identification terminal S2 by the first detection unit 1041 and the second detection unit 1042, can identify short-circuit states including reverse connection with no power supply and short circuit; fault states including reverse connection with power supply and positive connection with low voltage; and standard states including positive connection with standard voltage and positive connection with no power supply. Only in the standard state will the control unit 101 control the connection unit 105 to enter the conduction state.

[0050] Please see Figure 3 , it is Figure 1 The diagram shows the specific circuit structure of the second detection unit in the switch recognition circuit. Figure 3 As shown, the second detection unit 1042 includes a first input terminal IN1, a first output terminal OUT1, a Zener diode D1, a capacitor C1, and a second transistor Q2.

[0051] The anode of the Zener diode D1 is electrically connected to the ground terminal GND, and the cathode of the Zener diode D1 is electrically connected to the first output terminal OUT1. The first output terminal OUT1 is electrically connected to the signal receiving terminal of the control unit 101. The first output terminal OUT1 is used to output a first detection signal when the second detection unit 1042 has not entered the current detection state, and also to output a current signal when the second detection unit 1042 enters the current detection state.

[0052] The fifth resistor R5 is electrically connected between voltage divider node A and the first output terminal OUT1. The sixth resistor R6 is electrically connected between voltage divider node A and ground terminal GND. The seventh resistor R7 is electrically connected between voltage divider node A and the first input terminal IN1. The first input terminal IN1 is electrically connected to the identification unit 102 and the connection unit 105, and is used to receive the second identification signal and the current signal.

[0053] Capacitor C1 is electrically connected between the ground terminal GND and the first output terminal OUT1.

[0054] The source of the second transistor Q2 is electrically connected to the first input terminal IN1, the drain of the second transistor Q2 is electrically connected to the voltage divider node A, the gate of the second transistor Q2 is electrically connected to the connection enable signal output terminal of the control unit 101 (not shown) via the eighth resistor R8, and the gate of the second transistor Q2 is also electrically connected to the ground terminal GND via the ninth resistor R9.

[0055] In this embodiment, when the identification unit 102 is in the identification state due to the first potential of the identification enable signal output by the control unit 101, the second transistor Q2 is also in the off state due to receiving the second potential of the connection enable signal output by the control unit 101. That is, the second detection unit 1042 is in the voltage detection state at this time. The first input terminal IN1 receives the first identification signal output by the identification unit 102. After the second detection unit 1042 performs voltage division processing on the first identification signal, it outputs the first detection signal to the control unit 101 through the first output terminal OUT1. The voltage division relationship between the first identification signal and the first detection signal is determined by the resistance values ​​and connection relationship of the fifth resistor R5, the sixth resistor R6, and the seventh resistor R7. Subsequently, the control unit 101 performs difference processing on the received first detection signal and the second detection signal to obtain a detection difference value. Then, it compares the detection difference value with the detection threshold. Only when the detection difference value is greater than the detection threshold value will the control unit 101 adjust the connection enable signal output to the gate of the second transistor Q2 and the connection unit 105 from the second potential to the first potential, so that the second transistor Q2 in the connection unit 105 and the second detection unit 1042 enter the conduction state. At the same time, the identification unit 102 will also exit the identification state and stop outputting the first identification signal under the action of the identification enable signal output by the control unit 101. At this time, the first input terminal IN1 receives the current signal output by the connection unit 105.

[0056] In this embodiment, the circuit structure of the first detection unit 1041 is similar to that of the second detection unit 1042. However, the first detection unit 1041 lacks the second transistor Q2 used for switching between voltage detection state and current detection state as in the second detection unit 1042. The function of the first detection unit 1041 is only to perform voltage division processing on the received second identification signal and output the second detection signal to the control unit 101.

[0057] Please see Figure 4 , it is Figure 1 The diagram shows the structural structure of the connection unit in the switch recognition circuit. (See attached diagram.) Figure 4 As shown, the connection unit 105 includes a first loop terminal J1, a second loop terminal J2, a second input terminal IN2, and multiple connection sub-units.

[0058] The second input terminal IN2 is electrically connected to the control unit 101 and is used to receive the connection enable signal output by the control unit 101. The connection enable signal is used to control the conduction or cutoff of multiple connection sub-units in the connection unit 105. The conduction or cutoff state of the multiple connection sub-units is the conduction or cutoff state of the connection unit 105.

[0059] The first circuit terminal J1 is electrically connected to the battery unit 103, which is used to make the battery unit 103 and the load device 300 form a conductive circuit when multiple connection sub-units are in the conducting state, so that the load device 300 can receive the battery signal output by the battery unit 103 and start.

[0060] The second circuit terminal J2 is electrically connected to the power supply device 200. When multiple connection sub-units are in the conducting state, the power supply device 200 and the load device 300 form a conductive circuit, so that the load device 300 can receive the power signal output by the power supply device 200 and start.

[0061] The plurality of connection subunits are all electrically connected between the first circuit terminal J1 and the second circuit terminal J2.

[0062] The structures of the multiple connecting subunits are similar. In this application, one of the connecting subunits is used as an example to describe the structure of each connecting subunit in detail.

[0063] The connection subunit includes a third transistor Q3 and a fourth transistor Q4.

[0064] The gate of the third transistor Q3 is electrically connected to the second input terminal IN2 through the twelfth resistor R12, the source of the third transistor Q3 is electrically connected to the first loop terminal J1, and the drain of the third transistor Q3 is electrically connected to the ground terminal GND.

[0065] The gate of the fourth transistor Q4 is electrically connected to the second input terminal IN2 through the thirteenth resistor R13, the source of the fourth transistor Q4 is electrically connected to the second loop terminal J2, and the drain of the fourth transistor Q4 is electrically connected to the ground terminal GND.

[0066] In this embodiment, the connection unit 105 includes three connection sub-units that operate in parallel. This means that if one connection sub-unit fails, the others can continue to operate, thus improving the current transmission capability of the connection unit 105. It is understood that the number of connection sub-units in the connection unit 105 can be increased or decreased according to actual needs, and this embodiment does not impose a specific limitation on this.

[0067] In this embodiment, both the battery unit 103 connected to the first circuit terminal J1 and the power supply device 200 connected to the second connection terminal can start the load device 300 when they form a conductive circuit with the load device 300. That is, the battery unit 103 in the switch identification circuit 100 provided in this application can also successfully start the load device 300 when the vehicle lacks a power supply device 200, including a battery.

[0068] In this embodiment, the connection unit 105 switches between an on state and an off state under the influence of the connection enable signal input at the second input terminal IN2. That is, if the connection unit 105 receives the first potential in the connection enable signal, the transistor in the connection unit 105 will be turned on, meaning the plurality of connection sub-units enter the on state. The battery unit 103 and the power supply device 200, electrically connected to the first circuit terminal J1 and the second circuit terminal J2, form a conductive circuit with the load device 300, causing the load device 300 to start. If the connection unit 105 receives the second potential in the connection enable signal, the transistor in the connection unit 105 will be turned off, meaning the plurality of connection sub-units enter the off state. The battery unit 103 and the power supply device 200, electrically connected to the first circuit terminal J1 and the second circuit terminal J2, cannot form a conductive circuit with the load device 300, causing the load device 300 to stop working.

[0069] Compared with the prior art, the switch identification circuit 100 disclosed in this application detects the voltage at the first connection terminal N1 and the second connection terminal N2, and can control the power supply device 200 to stop providing driving voltage to the load device 300 when the first identification terminal S1 and the second identification terminal S2 are directly or indirectly short-circuited. Therefore, the switch identification circuit 100 provided in this application can accurately identify whether the first connection terminal and the second connection terminal are in a dangerous short-circuit state compared with detection methods using transistors or optocouplers, thus providing higher safety for the load device 300 connected to the first connection terminal and the second connection terminal during startup.

[0070] The switch identification circuit and electric device disclosed in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principle and implementation of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​this application. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A switch identification circuit, characterized in that, It includes an identification unit, a detection unit, a control unit, a connection unit, a first connection terminal, and a second connection terminal, wherein, The identification unit is electrically connected to the first connection terminal and the second connection terminal, and is used to provide a conductive circuit when the first connection terminal and the second connection terminal are short-circuited. The identification unit includes a first identification terminal and a second identification terminal. The first identification terminal is electrically connected to the first connection terminal, and the second identification terminal is electrically connected to the second connection terminal. It is used to receive the voltage at the first connection terminal as a first identification signal and to receive the voltage at the second connection terminal as a second identification signal. The detection unit is electrically connected to the first connection terminal and the second connection terminal, respectively detecting the voltage of the first connection terminal and the second connection terminal, and outputting a first detection signal and a second detection signal accordingly. The detection unit includes a first detection unit and a second detection unit. The first detection unit is electrically connected to the first identification terminal and is electrically connected to the first connection terminal through the first identification terminal. The detection unit detects the voltage of the first connection terminal and outputs a first detection signal (either by receiving a first identification signal output from the first identification terminal). The second detection unit is electrically connected to the second identification terminal and is electrically connected to the second connection terminal through the second identification terminal. The detection unit detects the voltage of the second connection terminal and outputs a second detection signal (either by receiving a second identification signal output from the second identification terminal). The control unit is electrically connected to the detection unit and the connection unit, and is used to receive the first detection signal and the second detection signal, and determine whether the first connection terminal is short-circuited with the second connection terminal based on the first detection signal and the second detection signal. The connection unit is electrically connected to the power supply device, and the power supply device is used to provide driving voltage to the first connection terminal and the second connection terminal. Wherein, the first connection terminal is electrically connected to the positive terminal of the power supply device and the load device, and the second connection terminal is electrically connected to the negative terminal of the power supply device and the load device; If the first connection terminal is short-circuited with the second connection terminal, the control unit outputs a connection enable signal to the connection unit, and the connection unit controls the power supply device to stop providing the driving voltage.

2. The switch identification circuit according to claim 1, characterized in that, The step of determining whether the first connection terminal is short-circuited with the second connection terminal based on the first detection signal and the second detection signal includes: The control unit performs a difference calculation on the first detection signal and the second detection signal to obtain a detection difference. If the detection difference is zero, the first connection terminal and the second connection terminal are short-circuited, the control unit outputs the connection enable signal to the connection unit, and the connection unit controls the power supply device to stop providing the driving voltage.

3. The switch identification circuit according to claim 2, characterized in that, If the detection difference is negative, the first connection terminal and the second connection terminal are reversed, the control unit outputs the connection enable signal to the connection unit, and the connection unit controls the power supply device to stop providing the driving voltage; If the detection difference is positive and less than the detection threshold, the power supply device is in a low-voltage state, the control unit outputs the connection enable signal to the connection unit, and the connection unit controls the power supply device to stop providing the driving voltage; If the detection difference is positive and greater than the detection threshold, the control unit outputs the connection enable signal to the connection unit, and the connection unit controls the power supply device to provide the driving voltage to the first connection terminal and the second connection terminal.

4. The switch identification circuit according to claim 1, characterized in that, The detection unit is also electrically connected to the connection unit, and is used to receive the current signal output from the connection unit when the connection unit controls the power supply device to provide the driving voltage to the first connection terminal and the second connection terminal, and transmit the current signal to the control unit. The current signal is the current of the load device electrically connected to the first connection terminal and the second connection terminal when the power supply device starts running. The control unit is used to receive the current signal, compare the current signal with a current threshold, and output a connection enable signal to the connection unit based on the comparison result. The enable signal controls the connection unit to control the power supply device to provide or stop providing the driving voltage.

5. The switch identification circuit according to claim 4, characterized in that, The comparison of the current signal with a current threshold, and the output of a connection enable signal to the connection unit based on the comparison result, wherein the enable signal controls the connection unit to control the power supply device to provide or stop providing the driving voltage, includes: The control unit compares the current signal with the current threshold. If the current signal is less than the current threshold, the control unit outputs the connection enable signal to the connection unit, and the connection unit controls the power supply device to provide the drive voltage according to the connection enable signal; If the current signal is greater than or equal to the current threshold, the control unit outputs the connection enable signal to the connection unit, and the connection unit controls the power supply device to stop providing the drive voltage according to the connection enable signal.

6. The switch identification circuit according to claim 1, characterized in that, The first detection unit is electrically connected to the first connection terminal and the control unit, and is used to receive the voltage at the first connection terminal as a first identification signal, and to process the first identification signal and output a first detection signal to the control unit. The second detection unit is electrically connected to the second connection terminal and the control unit, and is used to receive the voltage at the second connection terminal as a second identification signal, and to process the second identification signal and output a second detection signal to the control unit; The second detection unit is electrically connected to the connection unit and is used to receive the current signal output from the connection unit when the connection unit controls the power supply device to provide the driving voltage to the first connection terminal and the second connection terminal, and output the current signal to the control unit.

7. The switch identification circuit according to claim 1, characterized in that, The switch identification circuit also includes a battery unit. The battery cell is electrically connected to the first connection terminal to maintain the voltage at the first connection terminal, so that there is a voltage difference between the voltage at the first connection terminal and the voltage at the second connection terminal. The battery unit is also electrically connected to the connection unit, and is used to output or stop outputting drive voltage to the first connection terminal and the second connection terminal under the control of the connection unit.

8. The switch identification circuit according to claim 7, characterized in that, The identification unit further includes a first transistor, wherein... The first identification terminal is electrically connected to the first connection terminal, and the second identification terminal is electrically connected to the second connection terminal; The first detection unit is electrically connected to the first identification terminal and is used to receive the voltage at the first identification terminal as the first identification signal. The second detection unit is electrically connected to the second identification terminal and is used to receive the voltage at the second identification terminal as the second identification signal. The battery cell is electrically connected to the first identification terminal, so that a voltage difference can still exist between the first identification terminal and the second identification terminal when the power supply device is missing in the circuit; The first resistor is electrically connected between the first identification terminal and the second identification terminal; The drain of the first transistor is electrically connected to the second identification terminal through a second resistor, the source of the first transistor is electrically connected to the ground terminal, and the gate of the first transistor is electrically connected to the control unit through a third resistor. If the gate of the first transistor enters the conducting state under the control of the identification enable signal output by the control unit, the first identification terminal, the second identification terminal, the second resistor and the ground terminal form a conductive circuit.

9. The switch identification circuit according to claim 6, characterized in that, The second detection unit includes a first input terminal, a first output terminal, a Zener diode, a capacitor, and a second transistor, wherein, The anode of the Zener diode is electrically connected to the ground terminal, and the cathode of the Zener diode is electrically connected to the first output terminal. The first output terminal is electrically connected to the control unit. The first output terminal is used to output the first detection signal when the second detection unit has not entered the current detection state, and is also used to output the current signal when the second detection unit enters the current detection state. The capacitor is electrically connected between the ground terminal and the first output terminal; The fifth resistor is electrically connected between the voltage divider node and the first output terminal, the sixth resistor is electrically connected between the voltage divider node and the ground terminal, the seventh resistor is electrically connected between the voltage divider node and the first input terminal, and the first input terminal is electrically connected to the identification unit and the connection unit for receiving the second identification signal and the current signal; The source of the second transistor is electrically connected to the first input terminal, the drain of the second transistor is electrically connected to the voltage divider node, and the gate of the second transistor is electrically connected to the control unit via the eighth resistor. Specifically, if the gate of the second transistor enters the on state under the control of the connection enable signal, the first input terminal receives the current signal; if it enters the off state under the control of the connection enable signal, the first input terminal receives the second identification signal.

10. The switch identification circuit according to claim 7, characterized in that, The connection unit includes a first loop terminal, a second loop terminal, a second input terminal, and multiple connection sub-units, wherein... The second input terminal is electrically connected to the control unit and is used to receive the connection enable signal output by the control unit. The connection enable signal is used to control the conduction or cutoff of the plurality of connection sub-units. The plurality of connection sub-units are all electrically connected between the first circuit terminal and the second circuit terminal; The first circuit terminal is electrically connected to the battery cell and is used to provide the voltage signal to the conductive circuit formed by the first connection terminal and the second connection terminal when the plurality of connection sub-units are in the on state; The second circuit terminal is electrically connected to the power supply device and is used to provide a driving voltage for the conductive circuit formed by the first connection terminal and the second connection terminal when the plurality of connection sub-units are in the conducting state.

11. An electric device, characterized in that, Includes the switch identification circuit, power supply device, and load device as described in any one of claims 1-10, wherein, The power supply device is electrically connected to the load device and is used to drive the load device to start when the power supply device and the load device form a conductive circuit; The switch identification circuit is electrically connected to the power supply device, and is used to enable the power supply device and the load device to form a conductive circuit when the connection unit in the switch identification circuit is controlled by the connection enable signal to provide a driving voltage to the first connection terminal and the second connection terminal.

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