Protection circuit of port circuit, port circuit and electronic equipment

Abstract

The utility model provides a protection circuit of a port circuit, the port circuit and electronic equipment. The protection circuit comprises a first switching circuit, a signal generation circuit and a second switching circuit, the first switching circuit is connected in series between a signal terminal of a communication port of a port circuit and a signal terminal of a conversion chip of the port circuit, and the first switching circuit is used for isolating a high-voltage signal at the communication port from entering the conversion chip when the first switching circuit is disconnected; the signal generation circuit is respectively connected with the first switching circuit and a power supply terminal of the communication port, is used for accessing a first power supply signal, and is used for outputting a control voltage to the first switching circuit based on the first power supply signal; the second switch circuit is connected with the signal terminal of the communication port, the first switch circuit and the feedback terminal of the conversion chip. The second switch circuit is used for accessing a second power supply signal output by the conversion chip through the feedback terminal. The protection circuit provided by the utility model can protect the conversion chip and reduce the cost of the port circuit at the same time.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronics, in particular to a protection circuit of a port circuit, the port circuit and an electronic device. BACKGROUND

[0002] The signal pin of the conversion chip of the existing port circuit has low voltage resistance, for example, the Configuration Channel (CC) pin and the Sideband Use (SBU) pin of the conversion chip, and the voltage resistance of the CC pin and the SBU pin is 5-6V. If the voltage signal mistakenly introduced into the signal pin exceeds the voltage resistance of the signal pin, the conversion chip will be damaged.

[0003] In order to protect the conversion chip, the prior art separately adds a highly integrated protection chip to the signal pin of the conversion chip. However, the highly integrated protection chip has high cost, resulting in increased cost of the port circuit. CONTENT OF THE UTILITY MODEL

[0004] To solve the above technical problems, the present application provides a protection circuit of a port circuit, the port circuit and an electronic device to protect the signal terminal of the conversion chip and reduce the cost of the port circuit.

[0005] The present application provides a protection circuit of a port circuit, which comprises a first switch circuit, a signal generation circuit and a second switch circuit. The first switch circuit is connected in series between the signal terminal of the communication port of the port circuit and the signal terminal of the conversion chip of the port circuit. The first switch circuit is used to isolate the high voltage signal at the communication port from entering the conversion chip when it is disconnected. The signal generation circuit is connected with the first switch circuit and the power supply terminal of the communication port respectively, and is used to input the first power supply signal. The signal generation circuit is used to output the control voltage to the first switch circuit based on the first power supply signal. The second switch circuit is connected with the signal terminal of the communication port, the first switch circuit and the feedback terminal of the conversion chip respectively. The second switch circuit is used to input the second power supply signal output by the conversion chip through the feedback terminal.

[0006] In an embodiment, the first switch circuit comprises a first switch tube and a diode, a first communication end of the first switch tube is connected with the signal terminal of the communication port and the second switch circuit respectively, a second communication end of the first switch tube is connected with the signal terminal of the conversion chip, and a control end of the first switch tube is connected with the signal generation circuit; a cathode of the diode is connected with the first communication end of the first switch tube, and an anode of the diode is connected with the second communication end of the first switch tube and the signal terminal of the conversion chip respectively; wherein, in the case that the external device needs to supply power to the protection circuit, when the external device is connected to the communication port, the second switch circuit is turned on to supply power to the protection circuit; the signal generation circuit outputs a control voltage based on a first power supply signal of the external device to turn on the first switch tube; and the conversion chip outputs a second power supply signal to the second switch circuit to turn off the second switch circuit; or in the case that the external device does not need to supply power to the protection circuit, the first switch tube and the second switch circuit are both in the on state, when the external device is connected to the communication port, the branch in which the external device, the first switch tube and the conversion chip are located is turned on, the conversion chip sends a signal to the external device through the diode, and outputs a second power supply signal to the second switch circuit to turn off the second switch circuit.

[0007] In an embodiment, the second switch circuit comprises a second switch tube, a pull-down resistor and a first resistor, a first communication end of the second switch tube is connected with the signal terminal of the communication port and the first switch circuit respectively; the pull-down resistor, one end of the pull-down resistor is connected with a second communication end of the second switch tube, and the other end of the pull-down resistor is grounded; one end of the first resistor is connected with a control end of the second switch tube and the signal terminal of the conversion chip respectively, and the other end of the first resistor is grounded.

[0008] In an embodiment, the signal generation circuit comprises a linear voltage stabilizing circuit, the linear voltage stabilizing circuit is connected with the power supply terminal and the first switch circuit, and is used for outputting a control voltage based on a first power supply signal to control the first switch circuit to work.

[0009] In an embodiment, the signal generation circuit further comprises a voltage dividing circuit, the voltage dividing circuit is connected with the linear voltage stabilizing circuit, and is used for outputting a second control voltage based on a first control voltage output by the linear voltage stabilizing circuit; wherein, the signal terminal comprises a CC signal terminal and an SBU signal terminal, the first switch circuit comprises two sub first switch circuits, one sub first switch circuit is connected in series between the CC signal terminal of the communication port and the CC signal terminal of the conversion chip, and is connected with the linear voltage stabilizing circuit; the other sub first switch circuit is connected in series between the SBU signal terminal of the communication port and the SBU signal terminal of the conversion chip, and is connected with the voltage dividing circuit.

[0010] In an embodiment, the signal terminal comprises a CC signal terminal and / or an SBU signal terminal.

[0011] In an embodiment, the CC signal terminal comprises two sub-CC signal terminals, the SBU signal terminal comprises two sub-SBU signal terminals; the first switch circuit comprises four sub-first switch circuits, two of which are respectively connected between the sub-CC signal terminal of the communication port and the sub-CC signal terminal of the conversion chip, and the other two are respectively connected between the sub-SBU signal terminal of the communication port and the sub-SBU signal terminal of the conversion chip, wherein the sub-CC signal terminal of the communication port is connected with the second switch circuit.

[0012] The application provides a port circuit, which comprises a communication port, a conversion chip, and the protection circuit, the first switch circuit is connected between the signal terminal of the communication port and the signal terminal of the conversion chip, the signal generation circuit is connected with the power supply terminal of the communication port, and the second switch circuit is connected with the signal terminal of the communication port and the feedback terminal of the conversion chip.

[0013] The application provides an electronic device, which comprises the port circuit.

[0014] In an embodiment, the electronic device comprises a hub or a docking station.

[0015] The application has the following beneficial effects: the protection circuit comprises the first switch circuit, the signal generation circuit, and the second switch circuit, and the first switch circuit is connected in series between the communication port and the signal terminal of the conversion chip, so that when the signal terminal of the communication port is invaded by a high-voltage signal, the first switch circuit can prevent the high-voltage signal from entering the conversion chip in the rear stage of the first switch circuit, thereby protecting the conversion chip from damage by the high-voltage signal and effectively protecting the use safety of the conversion chip; in addition, compared with a highly integrated protection chip, the first switch circuit is a discrete circuit structure, which can reduce the cost of the protection circuit and thus reduce the cost of the port circuit. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0017] Figure 1 is a structural schematic diagram of an embodiment of an electronic device provided by the application;

[0018] Figure 2 is a structural schematic diagram of an embodiment of a port circuit provided by the application;

[0019] Figure 3 is a circuit schematic diagram of an embodiment of a port circuit provided by the application. Detailed Implementation

[0020] 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 the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0022] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0023] This application provides an electronic device, see reference. Figure 1 , Figure 1 This is a schematic diagram of an embodiment of the electronic device provided in this application. The electronic device 20 includes a port circuit 10. See also... Figure 2 , Figure 2 This is a schematic diagram of a port circuit embodiment provided in this application. The port circuit 10 includes a communication port 100, a conversion chip 300, and a protection circuit 200. The protection circuit 200 is connected to both the communication port 100 and the conversion chip 300. The protection circuit 200 of the communication port 100 is used to isolate high-voltage signals at the communication port 100 from entering the conversion chip 300. In this application, the high-voltage signal refers to an electrical signal exceeding the withstand voltage of the signal terminals of the conversion chip 300. It is understood that the conversion chip 300's external terminals are mapped onto the communication port 100 to enable electrical and signal connections between the conversion chip 300 and external devices. These external devices can be computers, mobile phones, tablets, etc., and are not limited thereto.

[0024] In an embodiment, the electronic device 20 can be a hub or a docking station, without limitation.

[0025] In an embodiment, continuing to refer to Figure 2 , the protection circuit 200 comprises a first switch circuit 210, a signal generation circuit 220 and a second switch circuit 230. The first switch circuit 210 is connected in series between the signal terminal of the communication port 100 and the signal terminal of the conversion chip 300, and is used to isolate the high voltage signal at the communication port 100 from entering the conversion chip 300 when disconnected. The signal generation circuit 220 is connected with the first switch circuit 210 and the power supply terminal of the communication port 100, and is used to access the first power supply signal V1. The second switch circuit 230 is connected with the signal terminal of the communication port 100, the first switch circuit 210 and the feedback terminal of the conversion chip 300, respectively, and accesses the second power supply signal V2 output by the conversion chip 300 through the feedback terminal.

[0026] It can be known that the power supply of the port circuit 10 can come from an external device accessed through the communication port 100, i.e., the external device supplies power to the protection circuit 200, or from other power supply devices, i.e., other power supply devices supply power to the protection circuit 200, at this time, the port circuit 10 can charge the accessed external device. The power supply terminal of the communication port 100 is connected with the power supply terminal of the conversion chip 300. In the mode that the external device supplies power to the protection circuit 200, the external device accesses the communication port 100, the external device and the branch where the second switch circuit 230 are conducted, the voltage at the signal terminal of the external device is pulled down, and the external device supplies power to the port circuit 10. The signal generation circuit 220 outputs a control voltage (not marked in the figure) to the first switch circuit 210 based on the first power supply signal V1 to make the first switch circuit 210 conductive, while the conversion chip 300 outputs the second power supply signal V2 to the second switch circuit 230 to turn off the second switch circuit 230, so that the external device, the first switch circuit 210 and the conversion chip 300 can communicate normally. When the other power supply devices supply power to the port circuit 10, at this time, the first switch circuit 210 and the second switch circuit 230 are in a conductive state, after the external device accesses the communication port 100, the conversion chip 300 sends signals to the external device through the first switch circuit 210, and provides the second power supply signal V2 to the second switch circuit 230 to turn off the second switch circuit 230, so that the external device, the first switch circuit 210 and the conversion chip 300 can communicate normally. When the signal terminal of the communication port 100 is invaded by a high voltage signal, the first switch circuit 210 is disconnected to isolate the high voltage signal, so that the signal terminal of the conversion chip 300 is protected from the high voltage signal, achieving the effect of protecting the conversion chip 300.

[0027] The protection circuit 200 of the embodiment comprises a first switch circuit 210, a signal generating circuit 220 and a second switch circuit 230, and the first switch circuit 210 is connected in series between the signal terminal of the communication port 100 and the conversion chip 300. When the signal terminal of the communication port 100 is invaded by a high-voltage signal, the first switch circuit 210 is disconnected, which can isolate the high-voltage signal from the conversion chip 300 in the next stage of the first switch circuit 210, thereby protecting the conversion chip 300 from the high-voltage signal and effectively protecting the conversion chip 300. In addition, compared with a highly integrated protection chip, the first switch circuit 210 is a discrete circuit structure, which can reduce the cost of the protection circuit 200 and thus the cost of the communication port 100 circuit. In addition, the protection circuit 200 can realize external device access detection of the port circuit 10 and on-off control of the first switch circuit through the signal generating circuit 220 and the second switch circuit 230, which can increase the use function of the protection circuit 200 and enhance the practicability of the protection circuit 200.

[0028] In one embodiment, referring to Figure 3 , Figure 3is a circuit schematic diagram of an embodiment of the port circuit provided in the present application. The first switch circuit 210 comprises a first switch tube Q11 and a diode D11. The first communication end of the first switch tube Q11 is connected with the signal terminal of the communication port 100, the second switch circuit 230 and the cathode of the diode D11 respectively, the second communication end of the first switch tube Q11 is connected with the signal terminal of the conversion chip 300 and the anode of the diode D11, and the control end of the first switch tube Q11 is connected with the signal generation circuit 220. In the case that the external device supplies power to the protection circuit 200, after the external device accesses the communication port 100, the second switch circuit 230 is turned on, so that the external device supplies power to the signal generation circuit 220 and the conversion chip 300. The signal generation circuit 220 outputs a control voltage to the control end of the first switch circuit 210 based on the first power supply signal V1, so that the first switch tube Q11 is turned on, and at the same time, the conversion chip 300 outputs the second power supply signal V2 to the second switch circuit 230 to turn off the second switch circuit 230, so that the external device can normally communicate with the conversion chip 300 through the first switch tube Q11. Alternatively, in the case that the external device does not need to supply power to the protection circuit 200, i.e. in the case that other power supply devices supply power to the port circuit 10 so that the port circuit 10 supplies power to the external device, at this time, the first switch tube Q11 and the second switch circuit 230 are both in the turned-on state. After the external device accesses the communication port 100, the conversion chip 300 sends a signal to the external device through the diode D11 and provides the second power supply signal V2 to the second switch circuit 230 to turn off the second switch circuit 230, so that the external device can normally communicate with the conversion chip 300 through the first switch tube Q11. After information communication, the port circuit 10 supplies power to the external device. When the signal terminal of the communication port 100 intrudes into a high-voltage signal, the voltage of the signal terminal of the communication port 100 and the signal terminal of the conversion chip 300 both rises. However, when the voltage at the signal terminal of the conversion chip 300 rises to the threshold value of the first switch tube Q11, for example, 5.5V, the first switch tube Q11 enters the saturation region, and the voltage on the signal terminal of the conversion chip 300 will not rise with the rise of the voltage on the signal terminal of the communication port 100, but will be clamped at a fixed value. Therefore, the first switch tube Q11 can isolate the high-voltage signal from entering the signal terminal of the conversion chip 300, and can protect the signal terminal of the conversion chip 300 from being damaged by the high-voltage signal, effectively protecting the conversion chip 300.

[0029] The first switch circuit 210 of the present embodiment only comprises the first switch tube Q11 and the diode D11, which has a simple structure, is easy to implement, has few components and low cost.

[0030] In an embodiment, the first switch tube Q11 comprises any one of a triode or a power tube, which is not limited herein.

[0031] In an embodiment, the first switch circuit 210 further comprises a clamping diode D12, two ends of the clamping diode D12 are connected with the second communication end and the control end of the first switch tube Q11 respectively.

[0032] In an embodiment, the first switch tube Q11, the diode D11 and the clamping diode D12 are integrally formed, that is, the first switch tube Q11, the diode D11 and the clamping diode D12 are integrally arranged, the diode D11 and the clamping diode D12 are additional functions of the first switch tube Q11 when the first switch tube Q11 is manufactured, and the stability of the first switch circuit 210 can be improved.

[0033] In an embodiment, the second switch circuit 230 comprises a second switch tube Q31, a pull-down resistor R31 and a first resistor R32. The first communication end of the second switch tube Q31 is connected with the signal terminal of the communication port 100 and the first switch circuit 210, the second communication end of the second switch tube Q31 is connected with one end of the pull-down resistor R31, and the other end of the pull-down resistor R31 is grounded GND. One end of the first resistor R32 is connected with the control end of the second switch tube Q31 and the feedback terminal of the conversion chip 300, and the other end of the first resistor R32 is grounded GND. In the mode that the external device supplies power to the protection circuit 200, when the communication port 100 accesses the external device, the external device is conducted with the branch in which the second switch tube Q31, the first resistor R32 and the pull-down resistor R31 are located, the voltage at the signal terminal of the external device is pulled down, the external device supplies power to the port circuit 10, the conversion chip 300 is powered and outputs the second power supply signal V2 to the control end of the second switch tube Q31, so that the second switch tube Q31 is cut off, thereby restoring the voltage at the signal terminal of the external device, and the external device can normally communicate with the conversion chip 300 through the first switch circuit 210. In the mode that the external device does not supply power to the protection circuit 200, the first switch circuit 210 and the second switch tube Q31 are in the conductive state, when the communication port 100 accesses the external device, the conversion chip 300 provides the second switch tube Q31 with the second power supply signal V2, so that the second switch tube Q31 is cut off, thereby the external device can normally communicate with the conversion chip 300 through the first switch circuit 210.

[0034] The second switch circuit 230 of the embodiment can realize conduction without a control signal when the communication port 100 accesses the external device or when the external device does not supply power, can realize automatic detection of the access of the external device, can facilitate the connection of the external device and the conversion chip 300, and has a simple structure, is easy to realize, and has few electronic components and low cost.

[0035] In an embodiment, the second switch Q31 includes any one of a triode or a power tube, which is not limited herein.

[0036] In an embodiment, in order to enhance the anti-interference ability of the second switch circuit 230, the second switch circuit 230 further includes a resistor R33, two ends of the resistor R33 are respectively connected with the feedback terminal of the conversion chip 300 and one end of the first resistor R32, and the resistor R33 cooperates with the first resistor R32 to form a voltage dividing circuit, so that the second power supply signal V2 enters the second switch Q31 after being divided, the second switch Q31 is protected, and the anti-interference ability of the second switch circuit 230 is enhanced.

[0037] In an embodiment, the resistance of the pull-down resistor R31 is 5.1KΩ, the resistance of the resistor R33 is 10KΩ, and the resistance of the first resistor R32 is 100KΩ. The resistances in the embodiment are all conventional general resistance values, and no special resistor is involved, so that a resistor for realizing a non-conventional resistance value such as a digital potentiometer is not needed, and the cost of the protection circuit 200 can be reduced. In other embodiments, the resistances of the pull-down resistor R31, the resistor R33 and the first resistor R32 can also be other reasonable conventional general resistance values, which are not limited herein.

[0038] In an embodiment, the signal generating circuit 220 includes a linear voltage stabilizing circuit 221, which is connected with the power supply terminal of the communication port 100 and the first switch circuit 210, and is used to output a control voltage based on the first power supply signal V1 to control the first switch circuit 210 to be turned on. It can be understood that the linear voltage stabilizing circuit 221 converts the first power supply signal V1, and still outputs a control voltage with small amplitude modulation and stability when the amplitude modulation of the first power supply signal V1 increases, so as to continue to control the first switch circuit 210 to be turned on and protect the first switch circuit 210, and enhance the stability of the first switch circuit 210; in addition, the signal generating circuit 220 in the embodiment has a simple structure and is easy to realize.

[0039] In an embodiment, the linear voltage stabilizing circuit 221 can be a conventional linear voltage stabilizing circuit, and the linear voltage stabilizing circuit 221 can also be an integrated power conversion chip, which is not limited herein.

[0040] In an embodiment, the linear voltage stabilizing circuit 221 includes a power conversion chip 300 and a peripheral circuit for maintaining normal work of the power conversion chip 300.

[0041] In an embodiment, the signal generating circuit 220 comprises a feedback resistor R22 with variable resistance and a resistor R21, the feedback resistor R22 and the resistor R21 are connected in series and connected to the output terminal and the feedback terminal of the linear voltage stabilizing circuit 221 respectively, and the feedback resistor R22 can be used to adjust the control voltage output by the linear voltage stabilizing circuit 221. It can be understood that the value of the control voltage output by the linear voltage stabilizing circuit 221 can be adjusted by adjusting the value of the feedback resistor R22, and thus the different control voltage requirements of the different first switch circuits 210 can be compatible.

[0042] In an embodiment, the feedback resistor R22 comprises a digital potentiometer (not shown in the figure) and / or a fixed resistor, the control terminal of the digital potentiometer can be connected to the control terminal of the port circuit 10, and the port circuit 10 can change the output of the digital potentiometer to adjust the resistance of the feedback resistor R22, and thus adjust the control voltage output by the linear voltage stabilizing circuit 221. In this embodiment, the adjustable feedback resistor R22 is realized by setting the digital potentiometer, and since the digital potentiometer can output unconventional resistance values, accurate adjustment of the control voltage can be realized.

[0043] In an embodiment, the control voltage comprises a first control voltage EN_V1 and a second control voltage EN_V2. The signal generating circuit 220 further comprises a voltage dividing circuit (not shown in the figure), which is connected to the linear voltage stabilizing circuit 221, and is used to output the second control voltage EN_V2 based on the first control voltage EN_V1 output by the linear voltage stabilizing circuit 221. Wherein, the signal terminal comprises a CC signal terminal and an SBU signal terminal, and the first switch circuit 210 comprises two sub-first switch circuits (not shown in the figure), one of which is connected in series between the communication port 100 and the CC signal terminal of the conversion chip 300, and is connected to the linear voltage stabilizing circuit 221. The other sub-first switch circuit 210 is connected in series between the communication port 100 and the SBU signal terminal of the conversion chip 300, and is connected to the voltage dividing circuit. It can be understood that the signal generating circuit 220 sets the linear voltage stabilizing circuit 221 and the voltage dividing circuit to output the first control voltage EN_V1 and the second control voltage EN_V2 respectively, so as to meet the different control voltage requirements of the sub-first switch circuits on different signal terminals of the conversion chip 300, and to reduce the settings of the signal generating circuit 220 or the linear voltage stabilizing circuit 221, thereby reducing the cost of the protection circuit 200.

[0044] In an embodiment, the voltage dividing circuit comprises a resistor R23 and a resistor R24, wherein the resistor R23 or the resistor R24 can be a digital potentiometer. In this embodiment, the digital potentiometer is used as a dividing resistor, and the digital potentiometer can output different resistance values, so the output of the digital potentiometer can be adjusted to adjust the value of the second control voltage EN_V2, so as to meet the control voltage requirements of the sub-first switch circuits on different signal terminals.

[0045] In an embodiment, the signal terminals include CC signal terminals and / or SBU signal terminals. The embodiment sets the first switch circuit 210 between the CC signal terminals and / or the SBU signal terminals between the communication port 100 and the conversion chip 300, so as to isolate the high-voltage signal at the communication port 100 from entering the conversion chip 300 through the first switch circuit 210, so that the CC signal terminals and the SBU signal terminals of the conversion chip 300 can be protected by the first switch circuit 210, and the damage probability of the conversion chip 300 can be reduced.

[0046] In an embodiment, the CC signal terminals include two sub-CC signal terminals, and the SBU signal terminals include two sub-SBU signal terminals. The first switch circuit 210 includes four sub-first switch circuits, two of which are respectively connected in series between the sub-CC signal terminals of the communication port 100 and the conversion chip 300. The other two sub-first switch circuits are respectively connected in series between the sub-SBU signal terminals of the communication port 100 and the conversion chip 300. Among them, the second switch circuit 230 is only connected with one of the sub-CC signal lines, for detecting whether an external device is connected, for example, the CC signal terminals include CC1 signal terminals and CC2 signal terminals, the second switch circuit 230 can be connected to the CC1 signal terminals of the communication port 100, or the second switch circuit 230 can be connected to the CC2 signal terminals of the communication port 100. It can be understood that the embodiment corresponds to a sub-first switch circuit in series in each sub-CC signal line and each sub-SBU signal line between the communication port 100 and the conversion chip 300, so as to isolate the high-voltage signal at the communication port 100 from entering the conversion chip 300 when the sub-first switch circuit is disconnected, so that each sub-CC signal terminal and each sub-SBU signal terminal of the conversion chip 300 can be protected by the sub-first switch circuit, and the damage probability of the conversion chip 300 can be reduced.

[0047] In an embodiment, the communication port 100 can be a Type-C, Type-A or Type-B communication port, which is not limited herein.

[0048] The above is only an embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation using the contents of the specification and drawings of the present application, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A protection circuit for a port circuit, characterized in that The application relates to a protection circuit for a communication port of a port circuit, comprising: a first switch circuit connected in series between a signal terminal of the communication port of the port circuit and a signal terminal of a conversion chip of the port circuit, the first switch circuit being used for isolating a high-voltage signal at the communication port from entering the conversion chip when the first switch circuit is turned off; a signal generating circuit connected with the first switch circuit and a power supply terminal of the communication port respectively, the signal generating circuit being used for inputting a first power supply signal and outputting a control voltage to the first switch circuit based on the first power supply signal; a second switch circuit connected with the signal terminal of the communication port, the first switch circuit and a feedback terminal of the conversion chip respectively, the second switch circuit being used for inputting a second power supply signal output by the conversion chip through the feedback terminal.

2. The protection circuit of claim 1, wherein, The first switch circuit comprises: a first switch tube, a first communication terminal of the first switch tube being connected with the signal terminal of the communication port and the second switch circuit respectively, a second communication terminal of the first switch tube being connected with the signal terminal of the conversion chip, and a control terminal of the first switch tube being connected with the signal generating circuit; a diode, a cathode of the diode being connected with the first communication terminal of the first switch tube, and an anode of the diode being connected with the second communication terminal of the first switch tube and the signal terminal of the conversion chip respectively; wherein, in the case that an external device needs to supply power to the protection circuit, when the external device is connected to the communication port, the second switch circuit is turned on to supply power to the protection circuit, the signal generating circuit outputs the control voltage based on the first power supply signal generated by the external device to turn on the first switch tube, and the conversion chip outputs the second power supply signal to the second switch circuit to turn off the second switch circuit; or in the case that the external device does not need to supply power to the protection circuit, the first switch tube and the second switch circuit are both in the on state, when the external device is connected to the communication port, a branch comprising the external device, the first switch tube and the conversion chip is turned on, the conversion chip sends a signal to the external device through the diode and outputs the second power supply signal to the second switch circuit to turn off the second switch circuit.

3. The protection circuit of claim 1, wherein, The second switch circuit comprises: a second switch tube, a first communication terminal of the second switch tube being connected with the signal terminal of the communication port and the first switch circuit respectively; a pull-down resistor, one end of the pull-down resistor being connected with a second communication terminal of the second switch tube, and the other end of the pull-down resistor being grounded; a first resistor, one end of the first resistor being connected with a control terminal of the second switch tube and a signal terminal of the conversion chip respectively, and the other end of the first resistor being grounded.

4. The protection circuit of claim 1, wherein The signal generating circuit comprises: a linear voltage stabilizing circuit connected with the power supply terminal and the first switch circuit, the linear voltage stabilizing circuit being used for outputting the control voltage based on the first power supply signal to control the first switch circuit to work.

5. The protection circuit of claim 4, wherein, The signal generating circuit further comprises: a voltage dividing circuit connected with the linear voltage stabilizing circuit, for outputting a second control voltage based on a first control voltage output by the linear voltage stabilizing circuit; wherein the signal terminals include CC signal terminals and SBU signal terminals, and the first switch circuit includes two sub-first switch circuits, one of which is connected in series between a CC signal terminal of the communication port and a CC signal terminal of the conversion chip and connected with the linear voltage stabilizing circuit; and the other of which is connected in series between an SBU signal terminal of the communication port and an SBU signal terminal of the conversion chip and connected with the voltage dividing circuit.

6. The protection circuit of claim 1, wherein, The signal terminals include CC signal terminals and / or SBU signal terminals.

7. The protection circuit according to claim 6, characterized in that, the CC signal terminals include two sub-CC signal terminals, and the SBU signal terminals include two sub-SBU signal terminals; the first switch circuit includes four sub-first switch circuits, two of which are connected in series between a sub-CC signal terminal of the communication port and a sub-CC signal terminal of the conversion chip respectively, and the other two of which are connected in series between a sub-SBU signal terminal of the communication port and a sub-SBU signal terminal of the conversion chip respectively, wherein one of the sub-CC signal terminals of the communication port is connected with the second switch circuit.

8. A port circuit, characterized by comprising: a communication port, a conversion chip, and the protection circuit according to any one of claims 1-7, the first switch circuit being connected in series between the signal terminals of the communication port and the signal terminals of the conversion chip, the signal generating circuit being connected with the power supply terminals of the communication port, and the second switch circuit being connected with the signal terminals of the communication port and the feedback terminals of the conversion chip respectively.

9. An electronic device, comprising: comprising the port circuit according to claim 8.

10. The electronic device according to claim 9, characterized in that, the electronic device includes a hub or a docking station.

Images