Protection circuit for terminal equipment and terminal equipment

Abstract

The invention discloses a protection circuit for terminal equipment and the terminal equipment, and the protection circuit comprises a peripheral detection module which is used for detecting whether a target interface is connected with peripheral equipment or not, and generating a peripheral detection signal; the main control module is used for configuring the target interface as a power-only interface when the target interface is not connected to the external equipment, configuring the target interface as a double-role interface when the target interface is connected to the external equipment, and generating an over-temperature protection signal when the interface temperature is greater than a preset interface temperature threshold value; the interface temperature detection module is used for generating an interface temperature detection signal; the interface protection module is used for controlling electrical conduction between the power supply end and the grounding end in response to the over-temperature protection signal. When it is determined that the target interface is not connected to the external equipment, the target interface is configured to be the power-only interface, the target interface is configured to be the double-role interface only when the external equipment is connected, the recognition function is started, and the risk that the target interface is polluted and corroded and is mistakenly recognized is reduced.

Description

Technical Field

[0001] This application relates to the field of electronic technology, specifically to a protection circuit for a terminal device and the terminal device itself. Background Technology

[0002] Currently, the Type-C interface has become the interface form that integrates data transmission and charging functions. Many terminal devices equipped with Type-C interfaces have appeared on the market, such as mobile phones, tablets, and laptops.

[0003] Because the Type-C interface on the terminal device is exposed to the air, it is easy for dust, liquid and other dirt to get in. When the Type-C interface is connected to an external device and forms a loop, it will cause the interface to short circuit, and in severe cases, it may even burn the interface.

[0004] Although related technologies use temperature monitoring circuits to monitor the temperature of the Type-C interface to protect it from over-temperature, when no external device is plugged into the Type-C interface, the configuration channel (CC) pin of the Type-C interface will be in recognition mode as soon as the terminal device is powered on, which increases the risk of the Type-C interface being contaminated, corroded, and misidentified. Summary of the Invention

[0005] In view of the above problems, this application provides a protection circuit and a terminal device for terminal devices to solve the above technical problems.

[0006] In a first aspect, this application provides a protection circuit for a terminal device, the protection circuit including a peripheral detection module, a main control module, an interface temperature detection module, and an interface protection module;

[0007] The peripheral detection module is connected to the target interface of the terminal device and is used to detect whether an external device is connected to the target interface and generate a peripheral detection signal.

[0008] The main control module, connected to the peripheral detection module, is used to configure the target interface as a power-only interface when the peripheral detection signal indicates that the target interface is not connected to an external device, to configure the target interface as a dual-role interface when the peripheral detection signal indicates that the target interface is connected to an external device, and to generate an over-temperature protection signal when the received interface temperature detection signal indicates that the interface temperature of the target interface is greater than a preset interface temperature threshold.

[0009] The interface temperature detection module is connected to the main control module and is used to detect the interface temperature of the target interface and generate an interface temperature detection signal.

[0010] The interface protection module is connected to the power supply terminal of the main control module and the terminal equipment. It is used to control the electrical conduction between the power supply terminal and the ground terminal in response to the over-temperature protection signal, so as to trigger short-circuit protection.

[0011] In one possible implementation of this application, the peripheral detection module is connected to the target pin of the target interface and the interrupt pin of the main control module, and the target pin is also connected to the power supply terminal; the peripheral detection module is used for:

[0012] When no external device is connected to the target interface, a first-level peripheral detection signal is generated based on the voltage signal at the power supply end;

[0013] When an external device is connected to the target interface, a second-level peripheral detection signal is generated in response to the received pin signal. The pin signal is the signal output by the pin corresponding to the target pin in the docking interface, and the docking interface is the interface in the external device that docks with the target interface.

[0014] In one possible implementation of this application, the peripheral detection module includes a comparison unit, a first voltage divider unit, and a second voltage divider unit. The first voltage divider node of the first voltage divider unit is connected to the target pin and the positive input terminal of the comparison unit, respectively. The second voltage divider node of the second voltage divider unit is connected to the negative input terminal of the comparison unit. The output terminal of the comparison unit is connected to an interrupt pin. The comparison unit is used for:

[0015] When the voltage of the first voltage divider node is greater than that of the second voltage divider node, a first-level peripheral detection signal is output. When no external device is connected to the target interface, the voltage of the first voltage divider node is greater than that of the second voltage divider node.

[0016] When the voltage of the first voltage divider node is less than that of the second voltage divider node, a second-level peripheral detection signal is output. When an external device is connected to the target interface, the voltage of the first voltage divider node is less than that of the second voltage divider node.

[0017] In one possible implementation of this application, the interface temperature detection module includes a resistive voltage divider unit and a thermistor voltage divider unit connected to the resistive voltage divider unit, and the connection node between the resistive voltage divider unit and the thermistor voltage divider unit is connected to the analog-to-digital sampling port of the main control module.

[0018] A thermistor voltage divider unit, connected in series with a resistor voltage divider unit, is used to respond to the interface temperature detection signal output to the analog-to-digital sampling port in response to the interface temperature regulation output, so that the main control module can determine the interface temperature based on the interface temperature detection signal.

[0019] In one possible implementation of this application, the interface protection module includes a first switch unit, the control terminal of the first switch unit is connected to the output port of the main control module, the first end of the first switch unit is connected to the power supply terminal, and the second end of the first switch unit is connected to the ground terminal.

[0020] The first switching unit is used to turn on in response to an over-temperature protection signal, so as to electrically connect the power supply terminal and the ground terminal.

[0021] In one possible implementation of this application, the protection circuit further includes a temperature protection module, which is connected to the charging circuit of the terminal device.

[0022] The temperature protection module is used to control the charging circuit to disconnect when the ambient temperature of the current environment of the terminal device is greater than the preset ambient temperature threshold.

[0023] In one possible implementation of this application, the temperature protection module includes an ambient temperature detection unit and a second switch unit. The ambient temperature detection unit is connected to the control terminal of the second switch unit and the first terminal of the second switch unit, respectively. The first terminal of the second switch unit is connected to the power supply terminal, and the second terminal of the second switch unit is connected to the system power supply terminal of the terminal device.

[0024] An ambient temperature detection unit is used to respond to the voltage difference between the control terminal of the second switching unit and the first terminal of the second switching unit in response to the ambient temperature.

[0025] The second switching unit is used to disconnect when the voltage difference is greater than a preset voltage difference threshold, so as to electrically disconnect the power supply terminal from the system power supply terminal.

[0026] In one possible implementation of this application, the ambient temperature detection unit includes a voltage divider resistor and a thermistor. The first end of the voltage divider resistor is connected to the first end of the second switching unit, the second end of the voltage divider resistor is connected to the first end of the thermistor and the control terminal of the second switching unit, and the second end of the thermistor is connected to the ground terminal.

[0027] In one possible implementation of this application, the protection circuit further includes a prompting module connected to the main control module;

[0028] The main control module is also used to issue a prompt signal when the interface temperature detection signal indicates that the interface temperature is greater than the preset interface temperature threshold.

[0029] The alert module is used to issue an alarm to the user in response to an alert signal, prompting the user to clean the target interface.

[0030] Secondly, this application also provides a terminal device, which includes a device body and a protection circuit as described in the first aspect disposed on the device body.

[0031] From the above, it can be concluded that this application has the following beneficial effects:

[0032] In this application, the peripheral detection module detects whether an external device is connected to the target interface. When no external device is connected, the main control module configures the target interface as a power-only interface to disable the identification function of the target interface. Only when an external device is connected to the target interface is the target interface configured as a dual-role interface to enable the identification function. At the same time, the interface temperature detection module detects the interface temperature. When the interface temperature is determined to be greater than the preset interface temperature threshold, the interface protection module is triggered by the over-temperature protection signal to control the short circuit between the power supply terminal and the ground terminal to trigger short circuit protection. This can reduce the risk of the target interface being contaminated and corroded and misidentified when no external device is connected, improve the safety of the target interface and terminal equipment, and extend the service life. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of a protection circuit for a terminal device provided in an embodiment of this application;

[0035] Figure 2 This is a schematic diagram of the peripheral detection module provided in the embodiments of this application;

[0036] Figure 3 This is a schematic diagram of the interface temperature detection module and protection module provided in the embodiments of this application;

[0037] Figure 4 This is a schematic diagram of another module of the protection circuit for terminal devices provided in the embodiments of this application;

[0038] Figure 5 This is a schematic diagram of the temperature protection module provided in the embodiments of this application;

[0039] Figure 6 This is another schematic diagram of a protection circuit for a terminal device provided in the embodiments of this application. Detailed Implementation

[0040] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0041] To enable those skilled in the art to better understand the solutions of this application, 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 a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0042] In the embodiments of this application, it should be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0043] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0044] In the description of the embodiments of this application, the words "example" or "for example" are used to indicate exemplification, illustration, or description. Any embodiment or design described as "example" or "for example" in the embodiments of this application is not to be construed as being more preferred or having more advantages than another embodiment or design. The use of the words "example" or "for example" is intended to present relative concepts in a clear manner.

[0045] Furthermore, in the embodiments of this application, "multiple" refers to two or more. Therefore, in the embodiments of this application, "multiple" can also be understood as "at least two". "At least one" can be understood as one or more, such as one, two, or more. For example, including at least one means including one, two, or more, and is not limited to which ones are included. For example, including at least one of A, B, and C, then it could include A, B, C, A and B, A and C, B and C, or A and B and C.

[0046] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0047] In the embodiments of this application, the first terminal / first end of each transistor is one of the source and the drain, and the second terminal / second end of each transistor is the other of the source and the drain. Since the source and drain of a transistor can be structurally symmetrical, they can be structurally indistinguishable. That is, the first terminal / first end and the second terminal / second end of the transistor in the embodiments of this application can be structurally indistinguishable. For example, when the transistor is a P-type transistor, the first terminal / first end is the source, and the second terminal / second end is the drain; for example, when the transistor is an N-type transistor, the first terminal / first end is the drain, and the second terminal / second end is the source.

[0048] In the circuit structure provided by the embodiments of this application, nodes such as the first node and the second node do not represent actual existing components, but rather represent the junction points of related couplings in the circuit diagram. In other words, these nodes are equivalent to the junction points of related couplings in the circuit diagram.

[0049] Before introducing the protection circuit for terminal devices and the terminal devices of this application, we will first introduce the relevant background information of the embodiments of this application.

[0050] For terminal devices equipped with Type-C interfaces, since the Type-C interface is often exposed to the air, dust, liquids and other dirt in the air can easily enter the Type-C interface. When the device is powered on, the dirt inside the Type-C interface can easily cause a micro-short circuit, which will cause the temperature of the Type-C interface to rise. In severe cases, the interface may even melt, posing a safety hazard.

[0051] In related technologies, the temperature of the Type-C interface is monitored by a temperature monitoring circuit to protect the Type-C interface from over-temperature. However, currently, when no external device is plugged into the Type-C interface, the CC pin of the Type-C interface will be in the recognition state as long as the terminal device is powered on, which undoubtedly increases the risk of the Type-C interface being contaminated, corroded, and misidentified.

[0052] Based on this, this application provides a protection circuit and a terminal device for a terminal device. The protection circuit detects whether an external device is connected to the target interface. When it is determined that no external device is connected to the target interface, the target interface is configured as a power-only interface to disable its identification function. Temperature detection and over-temperature protection are only performed when an external device is connected to the target interface. This reduces the risk of the target interface being contaminated and corroded, as well as being misidentified, improves the safety of the target interface and the terminal device, and extends its service life.

[0053] The protection circuit for terminal equipment and the terminal equipment provided in this application will be described in detail below.

[0054] First, this application provides a protection circuit for a terminal device. The protection circuit can be used in or integrated into the terminal device, which can be an electronic device such as a mobile phone, television, conference tablet, commercial display tablet, learning tablet, charging headphones, or charging speaker.

[0055] Please see Figure 1 , Figure 1 This is a schematic diagram of a protection circuit for a terminal device provided in an embodiment of this application. The protection circuit 100 for the terminal device may include a peripheral detection module 110, a main control module 120, an interface temperature detection module 130, and an interface protection module 140.

[0056] The peripheral detection module 110 can be connected to the target interface 200 of the terminal device to detect whether an external device is connected to the target interface 200 and generate a peripheral detection signal.

[0057] The main control module 120 can be connected to the peripheral detection module 110 and is used to configure the target interface 200 as a power-only interface when the peripheral detection signal indicates that the target interface 200 is not connected to an external device, configure the target interface 200 as a dual-role interface when the peripheral detection signal indicates that the target interface 200 is connected to an external device, and generate an over-temperature protection signal when the received interface temperature detection signal indicates that the interface temperature of the target interface 200 is greater than a preset interface temperature threshold.

[0058] The interface temperature detection module 130 can be connected to the main control module 120 to detect the interface temperature of the target interface 200 and generate an interface temperature detection signal.

[0059] The interface protection module 140 can be connected to the power supply terminal VBUS of the main control module 120 and the terminal device to control the electrical conduction between the power supply terminal and the ground terminal GND in response to the over-temperature protection signal, so as to trigger short-circuit protection.

[0060] In this embodiment of the application, the target interface 200 may be one or more interfaces provided by the terminal device, including but not limited to the Type-C interface or other interfaces that are the same as or similar to the Type-C interface. It is understood that the type of the target interface 200 may be determined according to the actual application scenario, and is not limited here.

[0061] The peripheral detection module 110 is connected to the target interface 200 and the main control module 120 respectively. It generates a peripheral detection signal and outputs it to the main control module 120 by detecting whether an external device is inserted at the target interface 200.

[0062] The main control module 120 can determine whether an external device is connected to the target interface 200 based on the received peripheral detection signal. For example, the connected and unconnected external devices can be distinguished by adjusting the level of the peripheral detection signal generated by the peripheral detection module 110.

[0063] For example, when an external device is connected to the target interface 200, the peripheral detection signal generated by the peripheral detection module 110 can be low level; conversely, when no external device is connected to the target interface 200, the peripheral detection signal generated by the peripheral detection module 110 can be high level.

[0064] In practical applications, the main control module 120 can be programmed in advance with a low-level peripheral detection signal corresponding to the case where an external device is connected to the target interface 200, and a high-level peripheral detection signal corresponding to the case where an external device is not connected to the target interface 200. Thus, the main control module 120 can determine whether an external device is connected to the target interface 200 based on the level of the received peripheral detection signal.

[0065] It is understood that in some other embodiments, a high-level peripheral detection signal can also correspond to the case where an external device is connected to the target interface 200, while a low-level peripheral detection signal can also correspond to the case where an external device is not connected to the target interface 200. The specific settings can be made according to the actual application scenario, and are not limited here.

[0066] When the main control module 120 determines that no external device is connected to the target interface 200 based on the peripheral detection signal, it can configure the target interface 200 as a power-only interface. Taking the target interface 200 as a Type-C interface as an example, it means setting the Type-C interface to SINK only, which means it can only be used as a power receiver, and disabling the CC detection function of the Type-C interface.

[0067] Conversely, if the main control module 120 determines that an external device is connected to the Type-C interface based on the peripheral detection signal, it can configure the Type-C interface as a Dual Role Port (DRP). This means that the CC1 and CC2 pins of the Type-C interface are enabled for detection. Depending on the orientation of the external device when it is connected to the Type-C interface, it determines whether the Type-C interface functions as a Downstream Facing Port (DFP) or an Upstream Facing Port (UFP). In other words, when the Type-C interface functions as a DFP, the terminal device can act as a host; when the Type-C interface functions as a UFP, the terminal device can act as a device.

[0068] It should be noted that although the above example uses the Type-C interface, the solution in this embodiment is also applicable to other types of interfaces that work in a similar or identical manner to the Type-C interface.

[0069] In this embodiment, the interface temperature detection module 130 can be positioned close to the target interface 200 and away from other heat sources in the terminal device to ensure accurate detection of the temperature of the target interface 200. The interface temperature detection module 130 is connected to the main control module 120, thereby outputting the generated interface temperature detection signal to the main control module 120.

[0070] After receiving the interface temperature detection signal, the main control module 120 can further determine whether the interface temperature is greater than the preset interface temperature threshold based on the interface temperature detection signal. If it is determined that the interface temperature is greater than the preset interface temperature threshold, the main control module 120 can generate an over-temperature protection signal and output it to the interface protection module.

[0071] Understandably, if there is dirt inside the target interface 200, it can easily cause micro-short circuits and heat generation inside the target interface 200, causing its temperature to rise. The preset interface temperature threshold can be set according to the actual application scenario. For example, the critical melting temperature of the target interface 200 under the current environment can be determined through multiple experiments, and the preset interface temperature threshold can be determined based on this critical melting temperature.

[0072] As an example, after multiple experiments, the critical melting temperature of the target interface 200 under the current environment is measured to be 75°C. Then, by subtracting a certain redundancy value, such as 10°C, from the critical melting temperature of 75°C, the preset interface temperature threshold can be obtained as 65°C. That is, when the interface temperature is greater than 65°C, the main control module 120 outputs an over-temperature protection signal to the interface protection module 140.

[0073] Upon receiving an over-temperature protection signal, the interface protection module 140 can respond to the signal by controlling the electrical connection between the power supply terminal VBUS and the ground terminal GND of the terminal device, thereby short-circuiting the power supply terminal VBUS to ground. The adapter connected to the target interface 200, i.e., the interface converter, can then trigger short-circuit protection, and the adapter will stop outputting, i.e., stop supplying power to the terminal device, in order to protect the target interface 200, i.e., the terminal device.

[0074] In this embodiment, the peripheral detection module 110 detects whether the target interface 200 is connected to an external device. When it is determined that no external device is connected, the main control module 120 configures the target interface 200 as a power-only interface to disable the identification function of the target interface 200. Only when the target interface 200 is connected to an external device is it configured as a dual-role interface to enable the identification function. At the same time, the interface temperature detection module 130 detects the interface temperature. When it is determined that the interface temperature is greater than the preset interface temperature threshold, the interface protection module 140 is triggered by the over-temperature protection signal to control the short circuit between the power supply terminal VBUS and the ground terminal GND to trigger short circuit protection. This can reduce the risk of the target interface 200 being contaminated and corroded and misidentified when no external device is connected, improve the safety of the target interface 200 and the terminal device, and extend the service life.

[0075] Next, continue with Figure 1 The unit modules shown are described in detail, as well as the specific implementation methods that may be used in practical applications.

[0076] In some embodiments of this application, the peripheral detection module 110 can be connected to the target pin of the target interface and the interrupt pin INT1 of the main control module 120, and the target pin is also connected to the power supply terminal VDD; the peripheral detection module 110 can specifically be used for:

[0077] When no external device is connected to the target interface 200, a first-level peripheral detection signal is generated based on the voltage signal of the power supply terminal VDD;

[0078] When an external device is connected to the target interface 200, a second-level peripheral detection signal is generated in response to the received pin signal. The pin signal is the signal output by the pin corresponding to the target pin in the docking interface, and the docking interface is the interface in the external device that docks with the target interface.

[0079] Taking the Type-C interface as an example, the B12 pin of the Type-C interface is a standard ground pin, which is usually connected to the ground terminal GND. In this embodiment, the B12 pin is used as the target pin, and the target pin is not connected to the ground terminal GND, but is pulled up to the power supply terminal VDD. At the same time, the peripheral detection module 110 is also connected to the interrupt pin INT1 of the main control module 120. The interrupt pin INT1 usually triggers the main control module 120 to interrupt when a low-level signal is received.

[0080] In this embodiment of the application, when no external device is connected to the Type-C interface, since the B12 pin is pulled up to the power supply terminal VDD, the peripheral detection module 110 can generate a first level, i.e. a high level peripheral detection signal based on the voltage signal of the power supply terminal VDD and output it to the interrupt pin INT1. At this time, the high level peripheral detection signal will not trigger the interrupt program of the main control module 120.

[0081] When an external device is connected via the Type-C interface, that is, when the Type-C interface is connected to the Type-C interface of the external device, the B12 pin of the Type-C interface of the external device is connected to the ground terminal GND. Therefore, the pin signal is a low-level signal. This low-level signal will pull the B12 pin of the Type-C interface of the terminal device low, so that the peripheral detection module 110 can generate a second level, that is, a low-level peripheral detection signal output to the interrupt pin INT1. At this time, the low-level peripheral detection signal will trigger the interrupt program of the main control module 120.

[0082] In this embodiment, by pulling up the B12 pin of the Type-C interface to the power supply VDD as the target pin, when an external device is connected, the B12 pin of the Type-C interface of the terminal device is pulled low through the B12 pin of the Type-C interface of the external device to trigger an interrupt in the main control module 120. The main control module 120 can thus determine the connection of the external device. The solution is simple and highly reliable.

[0083] like Figure 2 As shown, in some embodiments of this application, the peripheral detection module 110 may include a comparison unit 1101, a first voltage divider unit 1102, and a second voltage divider unit 1103. The first voltage divider node V1 of the first voltage divider unit 1102 is connected to the target pin B12 and the positive input terminal IN+ of the comparison unit 1101, respectively. The second voltage divider node V2 of the second voltage divider unit 1103 is connected to the negative input terminal IN- of the comparison unit 1101. The output terminal OUT of the comparison unit 1101 is connected to the interrupt pin INT1. The comparison unit 1101 can be used for:

[0084] When the voltage of the first voltage divider node V1 is greater than that of the second voltage divider node V2, a first-level peripheral detection signal is output. When no external device is connected to the target interface 200, the voltage of the first voltage divider node V1 is greater than that of the second voltage divider node V2.

[0085] When the voltage of the first voltage divider node V1 is less than that of the second voltage divider node V2, a second-level peripheral detection signal is output. When an external device is connected to the target interface 200, the voltage of the first voltage divider node V1 is less than that of the second voltage divider node V2.

[0086] As an example, the comparison unit 1101 may include a comparator U1, which may be any existing comparator, such as a comparator of model TLV7031DPWR X2SON. The first voltage divider unit 1102 may include a first resistor R1 and a second resistor R2 connected in series for voltage division, and the second voltage divider unit 1103 may include a third resistor R3 and a fourth resistor R4 connected in series for voltage division.

[0087] Specifically, the target pin B12 is connected to the positive input terminal IN+ of comparator U1 through the fifth resistor R5, and to the ground terminal GND through the bidirectional breakdown diode D1. The first resistor R1 and the second resistor R2 are connected in series, as are the third resistor R3 and the fourth resistor R4, to divide the voltage signal at the voltage terminal VREG. The first voltage divider node V1 of the first resistor R1 and the second resistor R2 is connected to the positive input terminal IN+ of comparator U1, and the second voltage divider node V2 of the third resistor R3 and the fourth resistor R4 is connected to the negative input terminal IN- of comparator U1. The output terminal OUT of comparator U1 is connected to the interrupt pin INT1 of the main control module 120.

[0088] In this embodiment, when no external device is connected to the target interface 200, the target pin B12 is pulled up to the power supply terminal VDD. By setting the resistance values ​​of the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4, it is ensured that the voltage of the first voltage divider node V1 is greater than the voltage of the second voltage divider node V2. As a result, the voltage at the positive input terminal IN+ of the comparator U1 is greater than the voltage at the negative input terminal IN-, and the output terminal OUT of the comparator U1 outputs a high-level peripheral detection signal.

[0089] When the target interface 200 is connected to an external device, the target pin B12 is pulled low from high level to ground, thereby pulling down the voltage of the first voltage divider node V1, while the voltage of the second voltage divider node V2 remains unchanged. Therefore, the voltage at the positive input terminal IN+ of comparator U1 is much smaller than the voltage at the negative input terminal IN-. The output terminal OUT of comparator U1 outputs a low-level peripheral detection signal to trigger the interrupt program of the main control module 120. The main control module 120 can thus confirm that an external device is connected to the target interface.

[0090] Understandable, although Figure 2 The first voltage divider unit 1102 and the second voltage divider unit 1103 shown in the figure each include two resistors connected in series for voltage division. However, in other embodiments, the number of resistors connected in series for voltage division in the first voltage divider unit 1102 and the second voltage divider unit 1103 can also be three, four or more. The specific number can be set according to the actual application scenario, and is not limited here.

[0091] The peripheral detection module 110 in this embodiment has a simple structure, high reliability, and uses conventional electronic components, making it easy to implement.

[0092] Please see Figure 3 In some embodiments of this application, the interface temperature detection module 130 may include a resistor voltage divider unit 1301 and a thermistor voltage divider unit 1302 connected to the resistor voltage divider unit 1301. The connection node V3 of the resistor voltage divider unit 1301 and the thermistor voltage divider unit 1302 is connected to the analog-to-digital sampling port ADC1 of the main control module 120.

[0093] The thermal voltage divider unit 1302 can be connected in series with the resistor voltage divider unit 1301 to divide the voltage in response to the interface temperature detection signal output to the analog-to-digital sampling port ADC1, so that the main control module 120 can determine the interface temperature based on the interface temperature detection signal.

[0094] For the Type-C interface, which has two VCC pins, there can be two interface temperature detection modules 130 in this embodiment. These two interface temperature detection modules 130 can be respectively arranged near the two VCC pins to detect the heat generation of the Type-C interface. The two interface temperature detection modules 130 have the same structure, therefore, only one interface temperature detection module 130 will be described.

[0095] The main control module 120 can be any existing system-on-chip (SOC) or system-on-a-chip. The resistor voltage divider unit 1301 can include a sixth resistor R6, and the thermistor voltage divider unit 1302 can include a first thermistor NTC1. The first thermistor NTC1 can be any existing thermistor, including but not limited to negative temperature coefficient thermistors (NTC) and positive temperature coefficient thermistors (PTC). It is understood that NTC is preferred in this embodiment.

[0096] The first thermistor NTC1 and the sixth resistor R6 are connected in series to divide the output voltage of the output voltage terminal V1. The resistance value of the first thermistor NTC1 decreases as the temperature increases, so the voltage divided by the first thermistor NTC1 also decreases as the temperature increases. That is, the voltage of the connection node V3 decreases as the temperature increases. Thus, as the interface temperature changes, the voltage of the interface temperature detection signal output to the analog-to-digital sampling port ADC1 of the main control module 120 changes. The main control module 120 can convert this voltage change into a temperature change, and then determine the interface temperature. The determined interface temperature is compared with a preset interface temperature threshold. When the interface temperature is greater than the preset interface temperature threshold, an over-temperature protection signal is generated and output from the output port GPIO1 to the interface protection module 140.

[0097] Please continue reading. Figure 3 In some embodiments of this application, the interface protection module 140 may include a first switch unit 1401. The control terminal of the first switch unit 1401 is connected to the output port GPIO1 of the main control module 120. The first terminal of the first switch unit 1401 is connected to the power supply terminal VBUS, and the second terminal of the first switch unit 1401 is connected to the ground terminal GND. The first switch unit 1401 can be used to turn on in response to an over-temperature protection signal so that the power supply terminal VBUS and the ground terminal GND are electrically connected.

[0098] In this embodiment, the output port GPIO1 can be any one of the multiple general purpose input / output ports (GPIO) of the main control module 120. The first switching unit 1401 can include any existing controllable transistor, including but not limited to transistors, such as NPN BJT and PNP BJT in bipolar junction transistors (BJTs), N-type MOS transistors and P-type MOS transistors in metal-oxide-semiconductor field-effect transistors (MOSFETs), etc. The specific selection can be made according to the actual application scenario, and is not limited here.

[0099] As an example, the first switching unit 1401 uses an NPN transistor Q1. The base of the NPN transistor Q1 is connected to the output port GPIO1 through the eighth resistor R8 and to the ground terminal GND through the seventh resistor R7. The collector of the NPN transistor Q1 is connected to the power supply terminal VBUS, and the emitter of the NPN transistor Q1 is connected to the ground terminal GND.

[0100] When the interface temperature is less than or equal to the preset interface temperature threshold, the output port GPIO1 of the main control module 120 is at a low level, thus turning off the NPN transistor Q1. When the interface temperature is greater than the preset interface temperature threshold, the output port GPIO1 of the main control module 120 goes high, outputting a high-level over-temperature protection signal. The NPN transistor Q1 responds to this high-level over-temperature protection signal and turns on, thus electrically connecting the power supply terminal VBUS and the ground terminal GND, i.e., short-circuiting the power supply terminal VBUS and the ground terminal GND, triggering the adapter to perform short-circuit protection to protect the target interface 200 and the terminal device, ensuring safety.

[0101] Because the battery of a terminal device will heat up during the charging process, especially when multiple terminal devices are placed in a charging cabinet for charging together, the temperature inside the charging cabinet will become too high. When charging at high temperatures, the battery of the terminal device is prone to bulging, which poses a safety hazard.

[0102] Based on this, such as Figure 4 As shown, in some embodiments of this application, the protection circuit may further include a temperature protection module 150, which may be connected to the charging circuit of the terminal device; the temperature protection module 150 may be used to control the charging circuit to disconnect when the ambient temperature of the current environment of the terminal device is greater than a preset ambient temperature threshold.

[0103] In this embodiment, the charging circuit of the terminal device can be a circuit that supplies power from the power supply terminal VBUS to its system power supply terminal Vbus. The power supply terminal VBUS can be a power module connected to the mains power supply. This power module can convert the mains power into a charging voltage suitable for the terminal device after rectification, step-down, and voltage regulation. The system power supply terminal Vbus can supply power to the various functional units inside the terminal device.

[0104] The temperature protection module 150 detects the ambient temperature of the current environment of the terminal device. When the ambient temperature is detected to be greater than the preset ambient temperature threshold, the temperature protection module 150 can control the charging circuit to disconnect, that is, disconnect the circuit between the power supply terminal VBUS and the system power supply terminal Vbus, so as to avoid the risk of battery swelling caused by floating charging of the terminal device in a high temperature environment, and further improve the safety and service life of the terminal device.

[0105] Please see Figure 5 In some embodiments of this application, the temperature protection module 150 may include an ambient temperature detection unit 1501 and a second switch unit 1502. The ambient temperature detection unit 1501 is connected to the control terminal of the second switch unit 1502 and the first terminal of the second switch unit 1502. The first terminal of the second switch unit 1502 is connected to the power supply terminal VBUS, and the second terminal of the second switch unit 1502 is connected to the system power supply terminal Vbus of the terminal device.

[0106] The ambient temperature detection unit 1501 can be used to regulate the voltage difference between the control terminal of the second switching unit 1502 and the first terminal of the second switching unit 1502 in response to the ambient temperature.

[0107] The second switching unit 1502 can be used to disconnect when the voltage difference is greater than a preset voltage difference threshold, so as to electrically disconnect the power supply terminal VBUS from the system power supply terminal Vbus.

[0108] In this embodiment, the ambient temperature detection unit 1501 is connected before the control terminal and the first terminal of the second switching unit 1502. The ambient temperature detection unit 1501 can change the voltage difference between the control terminal and the first terminal of the second switching unit 1502 according to the change of ambient temperature. When the voltage difference is less than the preset voltage difference threshold, the second switching unit 1502 remains on, so that the power supply terminal VBUS and the system power supply terminal Vbus are electrically connected, and power is supplied to the system power supply terminal Vbus through the power supply terminal VBUS. When the voltage difference is greater than the preset voltage difference threshold, the second switching unit 1502 is triggered to disconnect, so that the power supply terminal VBUS and the system power supply terminal Vbus are electrically disconnected, and the power supply terminal VBUS stops supplying power to the system power supply terminal Vbus, so as to avoid the terminal device from floating charge at high temperature.

[0109] Please continue reading. Figure 5 In some embodiments of this application, the ambient temperature detection unit 1501 may include a voltage divider resistor R9 and a thermistor NTC2. The first end of the voltage divider resistor R9 is connected to the first end of the second switching unit 1502, the second end of the voltage divider resistor R9 is connected to the first end of the thermistor NTC2 and the control terminal of the second switching unit 1502, and the second end of the thermistor NTC2 is connected to the ground terminal GND.

[0110] In this embodiment, the thermistor NTC2 can be any existing thermistor, including but not limited to NTC and PTC, with NTC being preferred in this embodiment. The second switching unit 1502 can be any existing controllable transistor, including but not limited to transistors, such as NPN BJT, PNP BJT, N-type MOSFET, and P-type MOSFET, etc. The specific choice can be made according to the actual application scenario, and is not limited here.

[0111] like Figure 5 As shown, the second switching unit 1502 includes a PMOS transistor Q2, a voltage divider resistor R9 and a thermistor NTC2 connected in series to divide the output voltage of the power supply terminal VBUS. The source S of the PMOS transistor Q2 is connected to the power supply terminal VBUS. The connection node V4 of the voltage divider resistor R9 and the thermistor NTC2 is connected to the gate G of the PMOS transistor Q2 through the tenth resistor R10. The drain D of the PMOS transistor Q2 is connected to the system power supply terminal Vbus. The drain D of the PMOS transistor Q2 is also connected to multiple parallel capacitors for filtering and for energy storage through the energy storage capacitor E1.

[0112] When the ambient temperature is low, the voltage divider resistor R9 and the thermistor NTC2 divide the voltage, and the voltage difference Vgs between the gate G and source S of PMOS transistor Q2 is less than the preset voltage difference threshold. PMOS transistor Q2 is turned on, so that the power supply terminal VBUS supplies power to the system power supply terminal Vbus.

[0113] As the charging time increases, the ambient temperature gradually rises. The resistance of the thermistor NTC2 decreases with increasing temperature, and thus the voltage across the thermistor NTC2 also decreases with increasing temperature. In other words, the voltage at connection node V4 decreases with increasing temperature. Consequently, the voltage difference Vgs between the gate G and source S of PMOS transistor Q2 increases. When the voltage difference Vgs exceeds the preset voltage difference threshold, PMOS transistor Q2 will be triggered to turn off, disconnecting the charging circuit from the power supply terminal VBUS to the system power supply terminal Vbus.

[0114] The preset differential voltage threshold can be the threshold voltage Vgs(th) of the PMOS transistor, and its value can be determined according to the selection and parameters of the PMOS transistor. It is not limited here.

[0115] In this embodiment, the ambient temperature of the terminal device during charging is detected by the thermistor NTC2. When the ambient temperature is too high, the PMOS transistor Q2 is triggered to automatically switch the charging circuit, thereby avoiding the terminal device from floating charge in a high-temperature environment, reducing the risk of battery bulging and improving safety.

[0116] like Figure 6 As shown, in some embodiments of this application, the protection circuit may further include a prompting module 160 connected to the main control module 120; the main control module 120 may also be used to issue a prompting signal when the interface temperature detection signal indicates that the interface temperature is greater than a preset interface temperature threshold; the prompting module 160 may be used to issue an alarm prompt to the user in response to the prompting signal, so as to prompt the user to clean the target interface.

[0117] In this embodiment of the application, when the main control module 120 determines that the interface temperature is greater than the preset interface temperature threshold, it can send a prompt signal to the prompt module 160 so that the prompt module 160 responds to the prompt signal and sends an alarm prompt to the user.

[0118] As an example, the prompt module 160 may be a display control module connected to the display screen of the terminal device. The display control module may respond to the prompt signal to control the display screen to display a pop-up prompt, informing the user that there is dirt inside the target interface 200 and that it needs to be cleaned in order to avoid the interface overheating and burning out.

[0119] As another example, the prompt module 160 can also be a power amplifier control module connected to the speaker of the terminal device. The power amplifier control module can drive the speaker to sound in response to the prompt signal to remind the user that there is dirt inside the target interface 200 and it needs to be cleaned in order to avoid the interface overheating and burning out.

[0120] Understandably, in another example, the prompting module 160 may include a display control module connected to the display screen of the terminal device and a power amplifier control module connected to the speaker of the terminal device, thereby prompting the user to clean the dirt simultaneously through a pop-up window on the display screen and a broadcast from the speaker.

[0121] Based on the above embodiments, this application also provides a terminal device, which may include a device body and a component disposed on the device body, such as... Figures 2 to 6 The protection circuit for the terminal device corresponds to any embodiment.

[0122] The terminal device can be an electronic device such as a mobile phone, television, conference tablet, commercial display tablet, learning tablet, charging headphones, or charging speaker.

[0123] Because the terminal device includes the present application, as described in this application Figures 2 to 6 Corresponding to the protection circuit for the terminal device in any embodiment, the present application can be implemented as described above. Figures 2 to 6 For all the beneficial effects that the protection circuit for the terminal device in any embodiment can achieve, please refer to the foregoing description, which will not be repeated here.

[0124] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Although this application has disclosed preferred embodiments as above, it is not intended to limit this application. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this application. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A protection circuit for terminal equipment, characterized in that, include: The peripheral detection module is connected to the target interface of the terminal device and is used to detect whether an external device is connected to the target interface and generate a peripheral detection signal. The main control module, connected to the peripheral detection module, is used to configure the target interface as a power-only interface when the peripheral detection signal indicates that the target interface is not connected to the external device, configure the target interface as a dual-role interface when the peripheral detection signal indicates that the target interface is connected to the external device, and generate an over-temperature protection signal when the received interface temperature detection signal indicates that the interface temperature of the target interface is greater than a preset interface temperature threshold. An interface temperature detection module, connected to the main control module, is used to detect the interface temperature of the target interface and generate the interface temperature detection signal; An interface protection module is connected to the power supply terminal of the main control module and the terminal device. It is used to control the electrical connection between the power supply terminal and the ground terminal in response to the over-temperature protection signal, so as to trigger short-circuit protection.

2. The protection circuit according to claim 1, characterized in that, The peripheral detection module is connected to the target pin of the target interface and the interrupt pin of the main control module, and the target pin is also connected to the power supply terminal; the peripheral detection module is used for: When the target interface is not connected to the external device, a first-level peripheral detection signal is generated based on the voltage signal of the power supply terminal; When the target interface is connected to the external device, a second-level peripheral detection signal is generated in response to the received pin signal, wherein the pin signal is the signal output by the pin corresponding to the target pin in the docking interface, and the docking interface is the interface in the external device that docks with the target interface.

3. The protection circuit according to claim 2, characterized in that, The peripheral detection module includes a comparison unit, a first voltage divider unit, and a second voltage divider unit. The first voltage divider unit's first voltage divider node is connected to the target pin and the positive input terminal of the comparison unit, respectively. The second voltage divider unit's second voltage divider node is connected to the negative input terminal of the comparison unit. The output terminal of the comparison unit is connected to the interrupt pin. The comparison unit is used for: When the voltage of the first voltage divider node is greater than that of the second voltage divider node, the first level peripheral detection signal is output, wherein the voltage of the first voltage divider node is greater than that of the second voltage divider node when the target interface is not connected to the external device; When the voltage of the first voltage divider node is less than that of the second voltage divider node, a peripheral detection signal of the second level is output, wherein when the external device is connected to the target interface, the voltage of the first voltage divider node is less than that of the second voltage divider node.

4. The protection circuit according to claim 1, characterized in that, The interface temperature detection module includes a resistive voltage divider unit and a thermistor voltage divider unit connected to the resistive voltage divider unit. The connection node between the resistive voltage divider unit and the thermistor voltage divider unit is connected to the analog-to-digital sampling port of the main control module. The thermistor voltage divider unit is connected in series with the resistor voltage divider unit to divide the voltage, and is used to respond to the interface temperature detection signal output by the interface temperature regulation to the analog-to-digital sampling port, so that the main control module determines the interface temperature based on the interface temperature detection signal.

5. The protection circuit according to claim 1, characterized in that, The interface protection module includes a first switch unit. The control terminal of the first switch unit is connected to the output port of the main control module, the first end of the first switch unit is connected to the power supply terminal, and the second end of the first switch unit is connected to the ground terminal. The first switching unit is configured to conduct in response to the over-temperature protection signal, thereby electrically connecting the power supply terminal and the ground terminal.

6. The protection circuit according to claim 1, characterized in that, The protection circuit also includes a temperature protection module, which is connected to the charging circuit of the terminal device; The temperature protection module is used to control the charging circuit to disconnect when the ambient temperature of the current environment where the terminal device is located is greater than a preset ambient temperature threshold.

7. The protection circuit according to claim 6, characterized in that, The temperature protection module includes an ambient temperature detection unit and a second switch unit. The ambient temperature detection unit is connected to the control terminal and the first terminal of the second switch unit, respectively. The first terminal of the second switch unit is connected to the power supply terminal, and the second terminal of the second switch unit is connected to the system power supply terminal of the terminal device. The ambient temperature detection unit is used to adjust the voltage difference between the control terminal of the second switching unit and the first terminal of the second switching unit in response to the ambient temperature. The second switching unit is used to disconnect when the voltage difference is greater than a preset voltage difference threshold, so as to electrically disconnect the power supply terminal from the system power supply terminal.

8. The protection circuit according to claim 7, characterized in that, The ambient temperature detection unit includes a voltage divider resistor and a thermistor. The first end of the voltage divider resistor is connected to the first end of the second switching unit, the second end of the voltage divider resistor is connected to the first end of the thermistor and the control terminal of the second switching unit, and the second end of the thermistor is connected to the ground terminal.

9. The protection circuit according to any one of claims 1-8, characterized in that, The protection circuit also includes a prompting module connected to the main control module; The main control module is also used to issue a prompt signal when the interface temperature detection signal indicates that the interface temperature is greater than the preset interface temperature threshold. The prompting module is used to issue an alarm prompt to the user in response to the prompting signal, so as to prompt the user to clean the target interface.

10. A terminal device, characterized in that, It includes the main body of the device and the protection circuit provided on the main body as described in any one of claims 1-9.

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