Electronic device

Abstract

The invention discloses electronic equipment, and relates to the technical field of electronic products. The electronic equipment comprises a charging connector, a charging chip, a temperature detection circuit, a control circuit and a switch piece, the temperature detection circuit comprises a diode, the negative electrode of the diode is the input end of the temperature detection circuit, and the charging connector comprises a first pin and a second pin; the first pin is electrically connected with the charging chip through a first connecting line, the second pin is electrically connected with the input end of the temperature detection circuit, the output end of the temperature detection circuit is electrically connected with the input end of the control circuit, the output end of the control circuit is electrically connected with the control end of the switch piece, and the first end of the switch piece is electrically connected with the first connecting line. The second end of the switch piece is grounded; wherein under the condition that the current value of the reverse leakage current in the diode is smaller than or equal to a first threshold value, the first end and the second end are disconnected; when the current value of the reverse leakage current in the diode is greater than the first threshold value, the first end and the second end are conducted.

Description

Technical Field

[0001] The present application relates to the technical field of electronic products, and in particular to an electronic device. Background Art

[0002] With the continuous upgrading of electronic product functions, most mobile phone Universal Serial Bus (USB) interfaces use Type-C interfaces. Compared with traditional USB interfaces, Type-C interfaces have more pins for data transmission, power transmission and other functions. The complexity of this design improves the application functions of the interface, but also increases the sensitivity to interface load and environmental corrosion.

[0003] Corrosion is a major issue facing USB ports. Exposure to humid environments or exposure to corrosive substances such as moisture, dirt, and chemicals can cause the metal contacts of the USB port to become poor conductors of electricity, increasing the risk of a short circuit. After a short circuit, a large current will flow through the PIN, which will cause the temperature of the PIN to rise during charging or other functional application scenarios. When the plastic of the USB socket reaches the melting point (usually 290°C), the USB socket will burn, which may also cause a safety incident.

[0004] Therefore, it is very important to monitor the USB interface temperature in real time. Through real-time temperature detection, the system can detect abnormal interface temperature in time and take corresponding measures.

[0005] In the related art, the main implementation method of over-temperature protection for electronic products is: a negative temperature coefficient thermistor (NTC) is placed near the USB Type-C interface to detect the temperature of the USB interface. When the electronic product is charging, if there is a foreign object or a short circuit, the temperature of the mobile phone USB interface will continue to rise. When the temperature value detected by the NTC reaches the set threshold, the over-temperature protection related strategy is triggered. However, in the solution in the related art, the NTC requires the CPU to collect and judge the temperature in real time, and the CPU must remain awake. Since the CPU cannot sleep, power consumption will increase; therefore, in order to save power consumption, the related art usually only turns on the CPU temperature detection function in the charging scene. This easily leads to the problem that temperature detection cannot be performed in other functional scenes except the charging scene, that is, the over-temperature protection of the charging interface cannot be implemented in other functional scenes except the charging scene. Summary of the invention

[0006] The present application provides an electronic device, which is beneficial to improving the effect of over-temperature protection of a charging interface.

[0007] In a first aspect, the present application provides an electronic device, including a charging connector, a charging chip, a temperature detection circuit, a control circuit, and a switch, wherein the temperature detection circuit includes a diode, the cathode of the diode is the input end of the temperature detection circuit, and the charging connector includes a first pin and a second pin;

[0008] The first pin is electrically connected to the charging chip through a first connecting line, the second pin is electrically connected to the input end of the temperature detection circuit, the output end of the temperature detection circuit is electrically connected to the input end of the control circuit, the output end of the control circuit is electrically connected to the control end of the switch element, the first end of the switch element is electrically connected to the first connecting line, and the second end of the switch element is grounded;

[0009] Wherein, when the current value of the reverse leakage current in the diode is less than or equal to the first threshold value, the output end of the control circuit outputs a first control signal, and the switch element disconnects the first end and the second end;

[0010] When the current value of the reverse leakage current in the diode is greater than the first threshold, the output end of the control circuit outputs a second control signal, and the switch element conducts the first end and the second end.

[0011] In the embodiment of the present application, the cathode of the diode is electrically connected to the second pin, so that when the temperature of the second pin increases, the reverse leakage current in the diode will also increase accordingly. In this way, the corresponding relationship between the temperature of the second pin and the magnitude of the reverse leakage current in the diode can be predetermined, and when the current value of the reverse leakage current in the diode is greater than the first threshold, it is determined that the temperature of the charging connector is too high. At this time, the control circuit can automatically control the switch to conduct the first end and the second end, so that the first connection line is short-circuited to the ground, and then the charger triggers the overcurrent protection and does not output the voltage, avoiding the safety risk caused by high temperature. In this process, since there is no need for CPU intervention, only relying on the hardware circuit to realize the automatic temperature recognition and adaptive protection of the charging interface, it can be applied to temperature detection and over-temperature protection in various scenarios, and there is no need to keep the CPU in the awake state all the time, which is conducive to saving power consumption, thereby improving the effect of over-temperature protection of the charging interface. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is one of the schematic diagrams of the circuit structure between the charging connector and the charging chip in the embodiment of the present application;

[0013] Figure 2 This is the second schematic diagram of the circuit structure between the charging connector and the charging chip in the embodiment of the present application;

[0014] Figure 3It is a schematic diagram of the process of over-temperature protection in the embodiment of the present application. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0016] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0017] In the following, in conjunction with the accompanying drawings, an electronic device provided by an embodiment of the present application is described in detail through specific embodiments and application scenarios.

[0018] See also Figure 1 and Figure 2 , an electronic device provided in an embodiment of the present application, the electronic device comprises a charging connector 100, a charging chip 200, a temperature detection circuit 500, a control circuit 400 and a switch 300, the temperature detection circuit 500 comprises a diode 501, the cathode of the diode 501 is the input end of the temperature detection circuit 500, the charging connector 100 comprises a first pin 101 and a second pin 102;

[0019] The first pin 101 is electrically connected to the charging chip 200 through a first connecting line 600, the second pin 102 is electrically connected to the input end of the temperature detection circuit 500, the output end of the temperature detection circuit 500 is electrically connected to the input end of the control circuit 400, the output end of the control circuit 400 is electrically connected to the control end 301 of the switch element 300, the first end 302 of the switch element 300 is electrically connected to the first connecting line 600, and the second end 303 of the switch element 300 is grounded;

[0020] Wherein, when the current value of the reverse leakage current in the diode 501 is less than or equal to the first threshold value, the output end of the control circuit 400 outputs a first control signal, and the switch element 300 disconnects the first end 302 and the second end 303;

[0021] When the current value of the reverse leakage current in the diode 501 is greater than the first threshold, the output end of the control circuit 400 outputs a second control signal, and the switch element 300 conducts between the first end 302 and the second end 303 .

[0022] The electronic device mentioned above can be various types of electronic devices, for example, a mobile phone, a tablet computer, various smart wearable devices, etc.

[0023] The charging connector 100 may be a charging connector 100 in an electronic device for connecting to an external charger, and the external charger may charge the electronic device through the charging connector 100. The charging connector 100 may be a charging connector 100 of various types in an electronic device, and may be various USB connectors, for example, USB-A, USB-C, Lightning, and Micro USB.

[0024] It is understandable that the charging connector 100 usually includes a plurality of pins, wherein each pin in the charging connector 100 can be electrically connected to the CPU via an FPC, so that the signal on the charging connector 100 can be normally transmitted to the CPU for processing via a flexible printed circuit (FPC). In the embodiment of the present application, in addition to being connected to the CPU via an FPC, the pins in the charging connector 100 can also be electrically connected to the temperature detection circuit 500, wherein the temperature detection circuit 500 and the FPC can be considered to be connected in parallel, so that the working process of the temperature detection circuit 500 and the control circuit 400 will not affect the normal signal transmission process of the charging connector 100.

[0025] Since the above-mentioned temperature detection circuit 500 and control circuit 400 do not need to be connected to the CPU through FPC, the temperature detection circuit 500 and control circuit 400 will not occupy the whole machine analog-to-digital converter (ADC) resources and FPC resources.

[0026] The first pin 101 may be a pin in the charging connector 100 for charging. Accordingly, the first connecting line 600 may be Figure 1 and Figure 2 The VBUS line in the above-mentioned charging chip 200 can be the charging chip 200 in the battery module in the electronic device.

[0027] The second pin 102 may be any pin in the charging connector 100 , wherein the first pin 101 and the second pin 102 may be two different pins in the charging connector 100 , and furthermore, the first pin 101 and the second pin 102 may be the same pin in the charging connector 100 .

[0028] Among them, for diode 501, due to the diffusion of carriers within the diffusion length of the outer edge of the depletion region and the spatial generation of carriers in the depletion layer, there will be a small current, which is the reverse leakage current of diode 501. At the same time, the reverse leakage current of diode 501 is proportional to the temperature. The higher the temperature, the greater the reverse leakage current. This principle of diode 501 can complete the conversion of temperature to current.

[0029] It can be understood that during the operation of the charging connector 100, for example, when the charging connector 100 is connected to the charging cable to charge the electronic device, the pin in the charging connector 100 is in a positive potential state. At this time, a small part of the flow in the second pin 102 can flow through the diode 501 and leak to the circuit after the diode 501. The amount of electricity flowing through the diode 501 is the reverse leakage current of the above-mentioned diode 501.

[0030] The temperature detection circuit 500 can be a detection circuit for users to measure the temperature near the second pin 102, and the temperature detection circuit 500 can specifically convert the temperature value of the second pin 102 into an electrical signal to detect the temperature near the second pin 102. The electrical signal can be an electrical signal such as voltage or current.

[0031] The switch element 300 may be an N-type metal-oxide-semiconductor field-effect transistor (MOS), or may be a transistor of the same type as the N-type MOS transistor.

[0032] The switch 300 disconnects the first end 302 and the second end 303, that is, the first end 302 and the second end 303 of the switch 300 are in an open circuit state. At this time, the external charger can charge the electronic device normally through the second pin 102 and the first connecting line 600. Correspondingly, when the switch 300 conducts the first end 302 and the second end 303, since the second end 303 is grounded, VBUS is short-circuited to the ground, and the charger triggers the overcurrent protection and does not output the voltage, avoiding the safety risk caused by high temperature. After the charger triggers the overcurrent protection, when the temperature of the second pin 102 drops, the reverse leakage current in the diode 501 will also decrease. When the current value of the reverse leakage current in the diode 501 decreases to less than or equal to the second threshold, the ground-pulling MOS is restored, that is, the switch 300 disconnects the first end 302 and the second end 303. At this time, VBUS can output the voltage normally and charge, and restore to a normal state, wherein the second threshold is less than or equal to the first threshold.

[0033] In this embodiment, by electrically connecting the cathode of the diode 501 to the second pin 102, when the temperature of the second pin 102 increases, the reverse leakage current in the diode 501 will also increase accordingly. In this way, the corresponding relationship between the temperature of the second pin 102 and the magnitude of the reverse leakage current in the diode 501 can be predetermined, and when the current value of the reverse leakage current in the diode 501 is greater than the first threshold, it is determined that the temperature of the charging connector 100 is too high. At this time, the control circuit 400 can automatically control the switch 300 to conduct the first end 302 and the second end 303, so that the first connection line 600 is short-circuited to the ground, and then the charger triggers the overcurrent protection and does not output the voltage, avoiding the safety risk caused by high temperature. In this process, since there is no need for CPU intervention, only relying on the hardware circuit to realize the automatic temperature recognition and adaptive protection of the charging interface, it can be applied to temperature detection and over-temperature protection in various scenarios, and there is no need to keep the CPU in the awake state all the time, which is conducive to saving power consumption, thereby improving the effect of over-temperature protection of the charging interface.

[0034] Optionally, the control circuit 400 includes an operational amplifier circuit 410 and a control unit 420, the output end of the temperature detection circuit 500 is electrically connected to the input end of the operational amplifier circuit 410, the output end of the operational amplifier circuit 410 is electrically connected to the input end of the control unit 420, and the output end of the control unit 420 is electrically connected to the control end 301 of the switch element 300.

[0035] The operational amplifier circuit 410 can be used to amplify the detection result of the temperature detection circuit 500. The structure of the operational amplifier circuit 410 can be set according to the required amplification multiple.

[0036] In this embodiment, since the current value of the reverse leakage current flowing through the diode 501 is usually small, the detection value output by the temperature detection circuit 500 is also relatively small. Therefore, by setting an operational amplifier circuit 410 between the temperature detection circuit 500 and the control unit 420, the operational amplifier circuit 410 can amplify the detection value output by the temperature detection circuit 500, thereby facilitating the control unit 420 to control the switch element 300 based on the amplified detection value.

[0037] In the related art, due to the complex design of the Type-C USB socket, the NTC is generally placed behind the socket. It takes a certain time delay to transfer heat from the heat source of the USB socket to the NTC, which will affect the detection timeliness; and the final temperature of the heat transferred from different PINs to the NTC is quite different, which will affect the detection accuracy. Due to the layout of the whole machine, the USB interface is at the bottom of the whole machine, and the CPU is arranged at the top of the whole machine. The middle is connected through FPC. Test signal lines such as MOS_CTL and NTC_THM need to be transmitted through FPC, occupying FPC resources; if multiple NTCs are added to improve accuracy, the NTC signal needs to be routed on the FPC, resulting in more scarce resources on the FPC. The current NTC+MOS solution can only detect and protect the overall temperature of the USB port. Limited by the ADC resources of the CPU and the routing resources of the FPC, it is impossible to add accurate temperature detection protection to each individual PIN. There are not enough ADCs on the CPU side to collect NTC signals.

[0038] Optionally, the charging connector 100 includes at least two second pins 102 , and the control unit 420 includes at least two input terminals corresponding to the at least two second pins 102 ;

[0039] Each of the second pins 102 is electrically connected to a corresponding input terminal in the control unit 420 through one of the temperature detection circuits 500 and one of the operational amplifier circuits 410 .

[0040] The second pin 102 may be any pin in the charging connector 100. Specifically, the second pin 102 is a pin in the charging connector 100 used to transmit a specific signal in the related art, that is, in the embodiment of the present application, the number of pins in the charging connector 100 is not increased, but on the basis of the existing pins of the charging connector 100, the pins are connected to the temperature detection circuit 500, so that the temperature detection circuit 500 detects the temperature of the pins connected thereto.

[0041] The number of the second pins 102 included in the charging connector 100 can be set as needed. For example, all the pins in the charging connector 100 can be used as the second pins 102. In this case, the temperature of each pin in the charging connector 100 can be detected. For another example, only some important pins in the charging connector 100 can be used as the second pins 102. In this case, the temperature of some important pins in the charging connector 100 can be detected.

[0042] In this implementation, since the setting of the temperature detection circuit 500 and the control circuit 400 in the embodiment of the present application will not occupy the ADC resources and FPC resources of the entire machine, the temperature detection circuit 500 can be set at multiple second pins 102 as needed, which is conducive to achieving more accurate temperature detection.

[0043] Optionally, the control unit 420 includes a multi-way OR gate selector circuit, the multi-way OR gate selector circuit includes the at least two input terminals, and the output terminal of the multi-way OR gate selector circuit is the output terminal of the control unit 420;

[0044] Wherein, in the diodes 501 connected to the at least two second pins 102, when the current value of the reverse leakage current in each diode 501 is less than or equal to the first threshold value, the output end of the multi-way OR gate selector circuit outputs a first level, and the first control signal includes the first level;

[0045] When the reverse leakage current value of at least one diode 501 among the diodes 501 connected to the at least two second pins 102 is greater than the first threshold, the output end of the multi-way OR gate selector circuit outputs a second level, and the second control signal includes the second level, which is higher than the first level.

[0046] The first level may be a low level, and the second level may be a high level.

[0047] The above-mentioned multi-way OR gate selector circuit may include an OR gate multiplexer (Multiplexer, MUX). Among them, MUX is a combinational logic circuit with multiple inputs and a single output, and the OR gate multiplexer can implement the related logic of "OR gate". Specifically, Figure 1 and Figure 2As shown, since each second pin 102 is connected to the multi-way OR gate selector circuit through a set of separate temperature detection circuits 500 and operational amplifier circuits 410, the multi-way OR gate selector circuit can output a high level as long as the current value of the reverse leakage current in the diode 501 connected to any second pin 102 is greater than the first threshold. It can be understood that when the current value of the reverse leakage current in the diode 501 connected to more than two second pins 102 is greater than the first threshold, the multi-way OR gate selector circuit outputs a high level. Only when the current value of the reverse leakage current in the diodes 501 connected to all second pins 102 is less than or equal to the first threshold, the multi-way OR gate selector circuit will output a low level.

[0048] It can be understood that when the multi-way OR gate selector circuit outputs a high level, the switch element 300 turns on the first end 302 and the second end 303, and when the multi-way OR gate selector circuit outputs a low level, the switch element 300 turns off the first end 302 and the second end 303.

[0049] In this implementation, by making the control unit 420 include a multi-way OR gate selector circuit, when the temperature of any second pin 102 is too high, the over-temperature protection mechanism of the electronic device can be triggered, thereby facilitating improving the over-temperature protection effect of the electronic device.

[0050] Optionally, the switch element 300 includes an N-type MOS tube, the drain of the N-type MOS tube is the first end 302, the source of the N-type MOS tube is the second end 303, and the gate of the N-type MOS tube is the control end 301;

[0051] The threshold voltage of the N-type MOS tube is greater than the first level, and the threshold voltage of the N-type MOS tube is less than or equal to the second level.

[0052] The conduction condition of the above-mentioned N-type MOS tube is: the gate voltage is greater than the threshold voltage of the N-type MOS tube.

[0053] In this implementation, by making the switch element 300 include an N-type MOS tube, and making the threshold voltage of the N-type MOS tube greater than the first level, and the threshold voltage of the N-type MOS tube less than or equal to the second level, it is possible to achieve automatic temperature recognition and adaptive protection of the charging interface purely by hardware circuits without the need for CPU intervention.

[0054] Optionally, the temperature detection circuit 500 further includes a sampling resistor 502 , the anode of the diode 501 is grounded through the sampling resistor 502 , and the anode of the diode 501 is the output end of the temperature detection circuit 500 .

[0055] See also Figure 2 In some embodiments of the present application, the reverse leakage current in the diode 501 can be converted into the voltage at the anode of the diode 501 after flowing through the sampling resistor 502. Specifically, when the temperature of the second pin 102 increases, the reverse leakage current in the diode 501 connected to the second pin 102 will also increase with the increase in temperature, and accordingly, the sampling voltage of the sampling resistor 502 connected to the diode 501 will also increase, that is, the voltage of the anode of the diode 501 relative to the ground point will also increase. In this way, the temperature of the second pin 102 can be converted into the voltage at the anode of the diode 501.

[0056] In this implementation, by making the temperature detection circuit 500 further include a sampling resistor 502, the anode of the diode 501 is grounded through the sampling resistor 502, so that the temperature of the second pin 102 can be converted into a voltage at the anode of the diode 501, so as to facilitate subsequent amplification of the voltage at the anode of the diode 501 based on the operational amplifier circuit 410.

[0057] Optionally, the operational amplifier circuit 410 includes a first operational amplifier 411, a second operational amplifier 412, a third operational amplifier 413, a first resistor 414, a second resistor 415, a third resistor 416, a fourth resistor 417, a fifth resistor 418, a sixth resistor 419 and a seventh resistor 4110;

[0058] The positive input terminal of the first operational amplifier 411 is electrically connected to the output terminal of the temperature detection circuit 500, the negative input terminal of the second operational amplifier 412 is grounded, and the output terminal of the first operational amplifier 411 is electrically connected to the output terminal of the second operational amplifier 412 through the first resistor 414, the second resistor 415 and the third resistor 416 in sequence;

[0059] A first connection point is provided between the first resistor 414 and the second resistor 415, a second connection point is provided between the second resistor 415 and the third resistor 416, a negative input terminal of the first operational amplifier 411 is electrically connected to the first connection point, and a positive input terminal of the first operational amplifier 411 is electrically connected to the second connection point;

[0060] The output end of the first operational amplifier 411 is also electrically connected to the output end of the third operational amplifier 413 through the fourth resistor 417 and the fifth resistor 418 in sequence, and a third connection point is provided between the fourth resistor 417 and the fifth resistor 418, and the third connection point is electrically connected to the positive input end of the third operational amplifier 413;

[0061] The output end of the second operational amplifier 412 is also grounded through the sixth resistor 419 and the seventh resistor 4110 in sequence. A fourth connection point is provided between the sixth resistor 419 and the seventh resistor 4110. The fourth connection point is electrically connected to the negative input end of the third operational amplifier 413. The output end of the third operational amplifier 413 is the output end of the operational amplifier circuit 410.

[0062] See also Figure 2 In the embodiment of the present application, a schematic diagram of the structure of the temperature detection circuit 500 and the operational amplifier circuit 410 connected to two second pins 102 of the charging connector 100 is shown, wherein: Figure 2 The two parts selected by the dotted boxes are the temperature detection circuit 500 and the operational amplifier circuit 410 connected to the second pin 102 at the bottom, and the current above the two dotted boxes is the temperature detection circuit 500 and the operational amplifier circuit 410 connected to the second pin 102 at the top. Since the structure and working principle of the temperature detection circuit 500 and the operational amplifier circuit 410 connected to the two second pins 102 are the same, therefore, in order to avoid repetition, the structure and working principle of the temperature detection circuit 500 and the operational amplifier circuit 410 above the dotted box are further explained below by taking the temperature detection circuit 500 and the operational amplifier circuit 410 above the dotted box as an example:

[0063] See also Figure 2 In the embodiment of the present application, the diode 501 is represented as D1, the sampling resistor 502 is represented as Rs1, the first resistor 414 is represented as R1, the second resistor 415 is represented as R2, the third resistor 416 is represented as R3, the fourth resistor 417 is represented as R4, the fifth resistor 418 is represented as R5, the sixth resistor 419 is represented as R6, the seventh resistor 4110 is represented as R7, the first operational amplifier 411 is represented as OPA1, the second operational amplifier 412 is represented as OPA2, and the third operational amplifier 413 is represented as OPA3, the control unit 420 is represented as MUX, the reverse leakage current in the diode 501 is represented as I, the divided voltage of Rs1 is represented as Vs, the voltage of the positive electrode of the diode 501 is represented as V1, the voltage of the negative input terminal of OPA1 is represented as Vx, the voltage of the positive input terminal of OPA2 is represented as Vy, the voltage of the negative input terminal of OPA2 is represented as V2, the voltage of the positive input terminal of OPA3 is represented as Vu, the voltage of the negative input terminal of OPA3 is represented as Vw, the output terminal of OPA3 is represented as OPA OUT1, the voltage of the output terminal of OPA3 is represented as Vout, the voltage of the output terminal of OPA1 is represented as Vo1, and the voltage of the output terminal of OPA2 is represented as Vo2.

[0064] See also Figure 2 According to the principle of operational amplifier, Vx=V1; Vy=V2;

[0065] Since no current flows through the negative input terminal of the first operational amplifier 411 and the negative input terminal of the second operational amplifier 412, R1, R2, and R3 can be regarded as being in series, that is, the current passing through each resistor of R1, R2, and R3 is the same, and the current I = (Vx-Vy) / R2;

[0066] Then: (Vo1)-(Vo2)=I*(R1+R2+R3)=(Vx-Vy)*(R1+R2+R3) / R2;

[0067] At the same time, the current flowing through R6 is equal to the current flowing through R7. If the resistance values ​​of R6 and R7 are the same in the application, Vw = (Vo2) / 2 can be obtained;

[0068] Similarly, the current flowing through R4 is equal to the current flowing through R5. If the resistance values ​​of R4 and R5 are the same in the application, then Vout-Vu=Vu-Vo1;

[0069] Therefore, Vu = (Vout + Vo1) / 2;

[0070] From the characteristics of the operational amplifier, we know that Vu = Vw;

[0071] Then we can get: Vout = Vo2-Vo1;

[0072] From the previously obtained relationship of (Vo1)-(Vo2), it can be concluded that the output of the operational amplifier circuit 410 is:

[0073] Vout=(Vy-Vx)(R1+R2+R3) / R2;

[0074] In some embodiments of the present application, R1 is a 100K resistor, R2 is a 10K resistor, R3 is a 100K resistor, R4 and R5 are both 10K resistors, and R6 and R7 are both 10K resistors. The operational amplifier circuit 410 is equivalent to amplifying the collected voltage by 21 times, and at the same time, the front and rear stages of the circuit are isolated to avoid the influence of the current fluctuation of the diode 501 on the judgment of the rear stage. It can be understood that the voltage amplification factor of the operational amplifier circuit 410 can be changed by changing the resistance value of the above resistors.

[0075] In this implementation, by further configuring the structure of the operational amplifier circuit 410 , the collected voltage can be amplified, and the front and rear stages of the circuit are isolated, thereby preventing the current fluctuation of the diode 501 from affecting the judgment of the rear stage.

[0076] Optionally, the resistance value of the fourth resistor 417 is equal to the resistance value of the fifth resistor 418 .

[0077] In this implementation, by making the resistance value of the fourth resistor 417 equal to the resistance value of the fifth resistor 418 , it is helpful to simplify the operation multiple calculation process of the operational amplifier circuit 410 .

[0078] Optionally, the resistance value of the sixth resistor 419 is equal to the resistance value of the seventh resistor 4110 .

[0079] In this implementation, by making the resistance value of the sixth resistor 419 equal to the resistance value of the seventh resistor 4110 , it is helpful to simplify the operation multiple calculation process of the operational amplifier circuit 410 .

[0080] Optionally, the diode 501 is disposed adjacent to the second pin 102 .

[0081] In some embodiments of the present application, the electronic device may further include a sub-board, the sub-board is arranged near the charging connector 100, and the charging connector 100 may be connected to the sub-board, that is, the charging connector 100 may be a connector extending from the sub-board to the charging interface of the electronic device, and the temperature detection circuit 500 and the control circuit 400 may be arranged on the sub-board. In this way, it is convenient to arrange the diode 501 close to the corresponding second pin 102. In this way, compared with the related art, in which the NTC is placed at a farther position of the USB socket, in the embodiment of the present application, the distance between the diode 501 and the second pin 102 is closer, which is conducive to further improving the accuracy of temperature detection.

[0082] In this implementation, by arranging the diode 501 adjacent to the second pin 102 , it is beneficial to further improve the accuracy of the detection result of the temperature detection of the charging connector 100 , so as to further improve the effect of over-temperature protection.

[0083] It is understandable that the charging connector 100 in the embodiment of the present application can be used not only as a USB port on the mobile phone, but also for real-time temperature detection and adaptive protection inside other device chargers, data cables, etc. Other NTC protection scenarios on the whole device can also adopt the technical solution of the embodiment of the present application.

[0084] See also Figure 3 , is a schematic diagram of a process for over-temperature protection of an electronic device in an embodiment of the present application, which may specifically include the following steps:

[0085] The electronic equipment is powered on;

[0086] The temperature detection circuit 500 detects the reverse leakage current I in the diode 501;

[0087] When I is less than or equal to the first threshold value I-high, the control circuit 400 outputs the first control signal and continues to detect the reverse leakage current I in the diode 501;

[0088] When I is greater than the first threshold value T-high, the control circuit 400 outputs a second control signal, and the control circuit 400 controls the switch element 300 to conduct the first end 302 and the second end 303, and the first connecting line 600 is short-circuited to GND;

[0089] The charger triggers OCP to avoid heating;

[0090] When I is less than or equal to the second threshold value I-low, the control circuit 400 outputs a second control signal to control the switch element 300 to disconnect the first end 302 and the second end 303, and the first connecting line 600 is disconnected to GND;

[0091] The charger exits protection mode and resumes normal charging.

[0092] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. An electronic device, characterized in that: It includes a charging connector, a charging chip, a temperature detection circuit, a control circuit and a switch, wherein the temperature detection circuit includes a diode, the cathode of the diode is the input end of the temperature detection circuit, and the charging connector includes a first pin and a second pin; The first pin is electrically connected to the charging chip through a first connecting line, the second pin is electrically connected to the input end of the temperature detection circuit, the output end of the temperature detection circuit is electrically connected to the input end of the control circuit, the output end of the control circuit is electrically connected to the control end of the switch element, the first end of the switch element is electrically connected to the first connecting line, and the second end of the switch element is grounded; Wherein, when the current value of the reverse leakage current in the diode is less than or equal to the first threshold value, the output end of the control circuit outputs a first control signal, and the switch element disconnects the first end and the second end; When the current value of the reverse leakage current in the diode is greater than the first threshold, the output end of the control circuit outputs a second control signal, and the switch element conducts the first end and the second end.

2. The electronic device according to claim 1, characterized in that: The control circuit includes an operational amplifier circuit and a control unit, the output end of the temperature detection circuit is electrically connected to the input end of the operational amplifier circuit, the output end of the operational amplifier circuit is electrically connected to the input end of the control unit, and the output end of the control unit is electrically connected to the control end of the switch element.

3. The electronic device according to claim 2, characterized in that: The charging connector includes at least two second pins, and the control unit includes at least two input terminals corresponding to the at least two second pins one by one; Each of the second pins is electrically connected to a corresponding input terminal in the control unit through one of the temperature detection circuits and one of the operational amplifier circuits.

4. The electronic device according to claim 3, characterized in that: The control unit comprises a multi-way OR gate selector circuit, the multi-way OR gate selector circuit comprises the at least two input terminals, and the output terminal of the multi-way OR gate selector circuit is the output terminal of the control unit; Wherein, in the diodes connected to the at least two second pins, when the current value of the reverse leakage current in each diode is less than or equal to the first threshold, the output end of the multi-way OR gate selector circuit outputs a first level, and the first control signal includes the first level; When the reverse leakage current in at least one of the diodes connected to the at least two second pins has a current value greater than the first threshold, the output end of the multi-way OR gate selector circuit outputs a second level, and the second control signal includes the second level, which is higher than the first level.

5. The electronic device according to claim 4, characterized in that: The switch element comprises an N-type MOS tube, the drain of the N-type MOS tube is the first end, the source of the N-type MOS tube is the second end, and the gate of the N-type MOS tube is the control end; Among them, the threshold voltage of the N-type MOS tube is greater than the first level, and the threshold voltage of the N-type MOS tube is less than or equal to the second level.

6. The electronic device according to claim 2, characterized in that: The temperature detection circuit further includes a sampling resistor, the anode of the diode is grounded through the sampling resistor, and the anode of the diode is the output end of the temperature detection circuit.

7. The electronic device according to claim 6, characterized in that: The operational amplifier circuit includes a first operational amplifier, a second operational amplifier, a third operational amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor and a seventh resistor; The positive input terminal of the first operational amplifier is electrically connected to the output terminal of the temperature detection circuit, the negative input terminal of the second operational amplifier is grounded, and the output terminal of the first operational amplifier is electrically connected to the output terminal of the second operational amplifier through the first resistor, the second resistor and the third resistor in sequence; A first connection point is provided between the first resistor and the second resistor, a second connection point is provided between the second resistor and the third resistor, a negative input terminal of the first operational amplifier is electrically connected to the first connection point, and a positive input terminal of the first operational amplifier is electrically connected to the second connection point; The output end of the first operational amplifier is also electrically connected to the output end of the third operational amplifier through the fourth resistor and the fifth resistor in sequence, a third connection point is provided between the fourth resistor and the fifth resistor, and the third connection point is electrically connected to the positive input end of the third operational amplifier; The output end of the second operational amplifier is also grounded through the sixth resistor and the seventh resistor in sequence. A fourth connection point is provided between the sixth resistor and the seventh resistor. The fourth connection point is electrically connected to the negative input end of the third operational amplifier. The output end of the third operational amplifier is the output end of the operational amplifier circuit.

8. The electronic device according to claim 7, characterized in that: The resistance value of the fourth resistor is equal to the resistance value of the fifth resistor.

9. The electronic device according to claim 7, characterized in that: The resistance value of the sixth resistor is equal to the resistance value of the seventh resistor.

10. The electronic device according to any one of claims 1 to 9, characterized in that: The diode is disposed adjacent to the second pin.

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