Cable over-temperature protection circuit

Abstract

The invention provides a cable over-temperature protection circuit, which comprises a non-electric weak conduction module, a voltage-stabilized power supply module, a control module and a power supply switch, and is characterized in that configuration channel ports of a first cable plug and a second cable plug are connected through the non-electric weak conduction module; the two ends of the voltage-stabilized power supply module are used for being connected with a power bus port of the first cable plug and a power bus port of the control module respectively, and the first cable plug supplies power to the control module through the voltage-stabilized power supply module. The temperature monitoring port of the control module is used for receiving temperature signals about cables, and the power supply control port is connected with the controlled end of a power supply switch arranged between the power bus port of the first cable plug and the power bus port of the second cable plug. The control module controls the power supply switch to be switched off when the cable is determined to be over-temperature according to the temperature signal, the phenomenon of alternating power-on and power-off is avoided in the over-temperature protection period, and the service life of an equipment port is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of electricity, and more particularly to a cable over-temperature protection circuit. Background Art

[0002] The temperature of the charging cable will gradually increase during the charging process. Generally, the higher the charging power, the faster the cable temperature rises. Currently, the power of quickly charging a device using the Universal Serial Bus Fast Charging Technology has reached 240 watts. For the cable, it requires ultra-high safety performance. If the power is not cut off in time when the temperature is too high, there is a risk of damage to the cable at high temperature, and even a fire may occur.

[0003] In the traditional cable over-temperature protection design, usually two E-Marker chips with integrated temperature protection are set in the Universal Serial Bus Type-C cable (USB Type-C cable). When the cable temperature is too high, the E-Marker chip switches the power supply. During the over-temperature protection period, there will be a phenomenon that the cable temperature briefly restores power supply, making the device in an alternating state of power-on and power-off, shortening the life of the device port. Summary of the Invention

[0004] The present invention provides a cable over-temperature protection circuit, which can solve the defect of shortening the life of the device port in the existing design by constructing an improved cable over-temperature protection circuit.

[0005] To solve the above technical problems, an embodiment of the present invention provides a cable over-temperature protection circuit, including:

[0006] A non-powered weak conduction module, whose first end is used to connect to the configuration channel port of the first cable plug, and whose second end is used to connect to the configuration channel port of the second cable plug; wherein, the non-powered weak conduction module is in a weak conduction state in the non-powered case;

[0007] A regulated power supply module, whose input end is used to connect to the power bus port of the first cable plug, and whose output end is connected to the power bus port of the control module;

[0008] The control module, its temperature monitoring port is used to receive the temperature signal of the cable, and its power supply control port is connected to the controlled end of the power supply switch; wherein, the control module is used to send an over-temperature protection signal to the controlled end of the power supply switch through the power supply control port when determining that the cable is over-temperature according to the temperature signal, so as to control the power supply switch to disconnect; the control module is also used to send a normal power supply signal to the controlled end of the power supply switch through the power supply control port when determining that the temperature of the cable is normal according to the temperature signal, so as to control the power supply switch to close;

[0009] The power supply switch, its first end is used to connect to the configuration channel port of the first cable plug, and its second end is used to connect to the configuration channel port of the second cable plug.

[0010] Compared with the prior art, the beneficial effect of the embodiment of the present invention is that the embodiment of the present invention provides a cable over-temperature protection circuit. The cable over-temperature protection circuit includes a non-powered weak conduction module, a regulated power supply module, a control module and a power supply switch. Both ends of the non-powered weak conduction module are used to connect to the configuration channel ports of the first cable plug and the second cable plug to realize connection detection between two devices for the power supply device to supply power; both ends of the regulated power supply module are respectively used to connect to the power bus port of the first cable plug and the power bus port of the control module, and the first cable plug supplies power to the control module through the regulated power supply module; the temperature monitoring port of the control module is used to receive the temperature signal of the cable, and the power supply control port is connected to the controlled end of the power supply switch arranged between the power bus port of the first cable plug and the power bus port of the second cable plug. In the embodiment of the present invention, the control module is used to send a normal power supply signal to the controlled end of the power supply switch through the power supply control port when determining that the temperature of the cable is normal according to the temperature signal, and send an over-temperature protection signal to the controlled end of the power supply switch through the power supply control port when determining that the cable is over-temperature according to the temperature signal, so as to control the power supply switch to disconnect. Using the cable over-temperature protection circuit can avoid the phenomenon of alternating power on and off during the over-temperature protection of the cable and extend the service life of the device port. Description of the Drawings

[0011] Figure 1 is a schematic structural diagram of a cable over-temperature protection circuit provided by a preferred embodiment of the present invention;

[0012] Figure 2 is a schematic structural diagram of a cable over-temperature protection circuit provided by a preferred embodiment of the present invention;

[0013] Figure 3 is a schematic structural diagram of a cable over-temperature protection circuit provided by a preferred embodiment of the present invention;

[0014] Figure 4It is a schematic structural diagram of a cable over-temperature protection circuit provided by a preferred embodiment of the present invention;

[0015] Figure 5 It is a schematic structural diagram of a cable over-temperature protection circuit provided by a preferred embodiment of the present invention;

[0016] Figure 6 It is a schematic structural diagram of a cable over-temperature protection circuit provided by a preferred embodiment of the present invention;

[0017] Figure 7 It is a schematic structural diagram of a cable over-temperature protection circuit provided by a preferred embodiment of the present invention;

[0018] Figure 8 It is a schematic structural diagram of a cable over-temperature protection circuit provided by a preferred embodiment of the present invention;

[0019] Figure 9 It is a schematic structural diagram of a cable over-temperature protection circuit provided by a preferred embodiment of the present invention.

[0020] Among them; 1. Power-off weak conduction module; 2. Control module; 3. Power supply orientation detection module; 4. First voltage comparison module; 5. Second voltage comparison module; PLUG-A, first cable plug; PLUG-B, second cable plug; CCA, configuration channel port of the first cable plug; CCB, configuration channel port of the second cable plug; VBUS1, power bus port of the first cable plug; VBUS2, power bus port of the second cable plug; VCC’, power bus port of the control module; S1, second pull-up switch; S2, second power-off weak conduction switch; S3, first power-off weak conduction switch; S4, first pull-up switch; S5, grounding switch; S6, power supply switch; R1, fifth feedback resistor; R2, fifth voltage-dividing resistor; R3, second feedback resistor; R4, second voltage-dividing resistor; R5, fourth feedback resistor; R6, fourth voltage-dividing resistor; R7, first feedback resistor; R8, first voltage-dividing resistor; R9, third feedback resistor; R10, third voltage-dividing resistor; Rp-A, second pull-up resistor; Rp-B, first pull-up resistor; Rd, grounding resistor; C_S1, second pull-up control port; C_S2, second configuration control port; C_S3, first configuration control port; C_S4, first pull-up control port; C_S5, grounding control port; C_S6, power supply control port; LDO, voltage stabilizing power supply module; D1, first unidirectional conduction module; D2, second unidirectional conduction module; VBUSA, first receiving port; VBUSB, second receiving port; COMP_CC, orientation signal receiving port; NTC, temperature monitoring port; Rntc, thermistor; U_VBUS1, first operational amplifier; U_VBUS2, second operational amplifier; U_CC, third operational amplifier. Detailed implementation manners

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] Please refer to Figure 1 , a preferred embodiment of the present invention provides a cable over-temperature protection circuit, including a non-powered weak conduction module 1, a voltage stabilization power supply module LDO, a control module 2, and a power supply switch S6.

[0023] The non-powered weak conduction module 1, its first end is used to connect to the configuration channel port CCA of the first cable plug PLUG-A, and its second end is used to connect to the configuration channel port CCB of the second cable plug PLUG-B; wherein, the non-powered weak conduction module 1 is in a weak conduction state when there is no power.

[0024] The voltage stabilization power supply module LDO, its input end is used to connect to the power bus port VBUS1 of the first cable plug PLUG-A, and its output end is connected to the power bus port VCC' of the control module 2.

[0025] The control module 2, its temperature monitoring port NTC is used to receive the temperature signal of the cable, and its power supply control port C_S6 is connected to the controlled end of the power supply switch S6; wherein, the control module 2 is used to send an over-temperature protection signal to the controlled end of the power supply switch S6 through the power supply control port C_S6 to control the power supply switch S6 to disconnect when it is determined that the cable is over-temperature according to the temperature signal; the control module 2 is also used to send a normal power supply signal to the controlled end of the power supply switch S6 through the power supply control port C_S6 to control the power supply switch S6 to close when it is determined that the cable temperature is normal according to the temperature signal.

[0026] The power supply switch S6, its first end is used to connect to the power bus port VBUS1 of the first cable plug PLUG-A, and its second end is used to connect to the power bus port VBUS2 of the second cable plug PLUG-B.

[0027] Specifically, both the first cable plug PLUG-A and the second cable plug PLUG-B have a power bus port, a configuration channel port, and a ground port GND. The ground port is used for grounding. Taking the first cable plug PLUG-A as a power supply device as an example, the first cable plug PLUG-A supplies power through the power bus port, and the second cable plug PLUG-B obtains power through the power bus port for charging or maintaining operation. The configuration channel port is used to detect whether two devices are connected, etc.

[0028] Specifically, the main function of the cable over-temperature protection circuit is to stop supplying power to the powered device in a timely manner when the cable temperature is too high, and to avoid the alternating change of power on and off during the over-temperature protection period, so as to extend the life of the cable. The cable over-temperature protection circuit mainly includes a non-powered weak conduction module 1, a voltage regulator power supply module LDO, a control module 2, and a power supply switch S6. Both ends of the non-powered weak conduction module 1 are respectively used to connect the configuration channel port CCA of the first cable plug PLUG-A and the configuration channel port CCB of the second cable plug PLUG-B. Both ends of the power supply switch S6 are respectively used to connect the power bus port VBUS1 of the first cable plug PLUG-A and the power bus port VBUS2 of the second cable plug PLUG-B. The input end of the voltage regulator power supply module LDO is used to connect to the power bus port VBUS1 of the first cable plug PLUG-A, and the output end VCC of the voltage regulator power supply module LDO is connected to the power bus port VCC' of the control module 2.

[0029] Assume that the voltage regulator module LDO is a low-dropout linear regulator. Taking the first device connected by the first cable plug PLUG-A as the power supply device (Source) and the second device connected by the second cable plug PLUG-B as the power receiving device (Sink) as an example, the working principle of the cable over-temperature protection circuit is as follows: (1) The control module 2 serves as the cable master. The non-powered weak conduction module 1 is in a weakly conductive state when there is no power. When the control module 2 has no power supply, the configuration channel signal (Configuration Channel, CC) at the Source end is sent from CCA, passes through the non-powered weak conduction module 1, and reaches the Sink end, thus completing the Type-C connection detection. Then, the Source end inputs through VBUS1 to the voltage regulator module LDO, and the voltage regulator module LDO starts to supply power to the control module 2. (2) After the control module 2 is powered on, it will first obtain the temperature signal of the cable. If the temperature is normal (that is, it is determined that the temperature of the cable is less than the set temperature threshold), it will send a normal power supply signal to the controlled end of the power supply switch S6 through the power supply control port C_S6, control the power supply switch S6 to close, and allow the Source end to supply power to the Sink end normally. It can be understood that the normal power supply signal is actually an electrical signal that triggers the power supply switch S6 to close. If the temperature is abnormal (that is, it is determined that the temperature of the cable is greater than or equal to the set temperature threshold), it will send an over-temperature protection signal to the controlled end of the power supply switch S6 through the power supply control port C_S6, control the power supply switch S6 to disconnect, and stop the Source end from supplying power to the Sink end to achieve temperature protection. It can be understood that the over-temperature protection signal is actually an electrical signal that triggers the power supply switch S6 to disconnect. (3) Optionally, since the Source end supplies power to the control module 2 through VBUS1 and the voltage regulator module LDO, the control module 2 can continue to monitor the temperature of the cable, and keep the power supply switch S6 in the disconnected state when the temperature of the cable is too high, avoiding repeated alternation of power supply and power-off between the Source end and the Sink end. Or, the control module 2 is also provided with a configuration control port for connecting the non-powered weak conduction module 1. When the control module 2 sends an over-temperature protection signal to the controlled end of the power supply switch S6, it sends a disconnection signal to the non-powered weak conduction module 1 through the configuration control port of the control module 2 to control the non-powered weak conduction module 1 to disconnect; when both the non-powered weak conduction module 1 and the power supply switch S6 are closed, the Source end turns off VBUS1 to stop supplying power to the control module 2. However, since the non-powered weak conduction module 1 is in a weakly conductive state when there is no power, the Source end re-implements the Type-C connection detection with the Sink end. After the connection detection is completed, the Source end re-supplies power to the control module 2 through the voltage regulator module LDO, and the control module 2 can continue to monitor the temperature of the cable, and keep the power supply switch S6 in the disconnected state when the temperature of the cable is too high, avoiding repeated alternation of power supply and power-off between the Source end and the Sink end.

[0030] Compared with the prior art, the cable over-temperature protection circuit provided by the embodiment of the present invention includes a non-powered weak conduction module 1, a voltage regulator power supply module LDO, a control module 2, and a power supply switch S6. Both ends of the non-powered weak conduction module 1 are used to be connected to the configuration channel port CCB of the first cable plug PLUG-A and the second cable plug PLUG-B to realize connection detection between two devices so that the power supply device can supply power; the input end and the output end of the voltage regulator power supply module LDO are respectively used to be connected to the power bus port VBUS1 of the first cable plug PLUG-A and the power bus port VCC' of the control module 2, and the ground end of the voltage regulator power supply module LDO is used for grounding. The first cable plug PLUG-A supplies power to the control module 2 through the voltage regulator power supply module LDO; the temperature monitoring port NTC of the control module 2 is used to receive the temperature signal of the cable, and the power supply control port C_S6 is connected to the controlled end of the power supply switch S6 arranged between the power bus port VBUS1 of the first cable plug PLUG-A and the power bus port VBUS2 of the second cable plug PLUG-B. In the embodiment of the present invention, the control module 2 is used to send a normal power supply signal to the controlled end of the power supply switch S6 through the power supply control port C_S6 when it is determined that the cable temperature is normal according to the temperature signal, and send an over-temperature protection signal to the controlled end of the power supply switch S6 through the power supply control port C_S6 when it is determined that the cable is over-temperature, so as to control the power supply switch S6 to disconnect. Using the cable over-temperature protection circuit can avoid the phenomenon of alternating power on and off during the over-temperature protection of the cable, and prolong the life of the device port.

[0031] In a preferred embodiment, referring to Figure 2 , on the basis of the above embodiment, the non-powered weak conduction module 1 includes a first non-powered weak conduction switch S3. The first end of the first non-powered weak conduction switch S3 is respectively connected to the first end of the non-powered weak conduction module 1 and the first end of the grounding module. The second end of the first non-powered weak conduction switch S3 is respectively connected to the second end of the non-powered weak conduction module 1 and the first end of the first pull-up module. The controlled end of the first non-powered weak conduction switch S3 is connected to the first configuration control port C_S3 of the control module 2;

[0032] The circuit further includes the grounding module and the first pull-up module; the grounding module includes a serially connected grounding resistor Rd and a grounding switch S5, the second end of the grounding module is used for grounding, and the controlled end of the grounding resistor Rd is connected to the grounding control port C_S5 of the control module 2; the first pull-up module includes a serially connected first pull-up resistor Rp-B and a first pull-up switch S4, the second end of the first pull-up module is used for connecting to the regulated power supply module LDO, and the controlled end of the first pull-up switch S4 is connected to the first pull-up control port C_S4 of the control module 2;

[0033] Wherein, the control module 2 is further configured to: when sending the over-temperature protection signal to the controlled end of the power supply switch S6 through the power supply control port C_S6, send a disconnection signal to the controlled end of the first non-powered weak conduction switch S3 through the first configuration control port C_S3 to control the first non-powered weak conduction switch S3 to disconnect; after the first non-powered weak conduction switch S3 automatically resumes the weak conduction state from the disconnected state, if it is determined that the cable is over-temperature, send a disconnection signal to the controlled end of the first non-powered weak conduction switch S3 through the first configuration control port C_S3, send a closing signal to the controlled end of the first pull-up switch S4 through the first pull-up control port C_S4, and send a closing signal to the controlled end of the grounding switch S5 through the grounding control port C_S5, so as to control the first non-powered weak conduction switch S3 to disconnect, and the first pull-up switch S4 and the grounding switch S5 to close;

[0034] The first device connected to the first cable plug PLUG-A is configured to output a low-level voltage through the power bus port VBUS1 of the first cable plug PLUG-A when the first non-powered weak conduction switch S3 is in the disconnected state and the first pull-up switch S4 and the grounding switch S5 are in the closed state;

[0035] The control module 2 is further configured to: when the power bus port VBUS1 of the first cable plug PLUG-A outputs the low-level voltage, control the power supply switch S6 to close.

[0036] Specifically, in Figure 2In the shown circuit, the first cable plug PLUG-A side is the Source end, and the second cable plug PLUG-B is the Sink end. When the control module 2 determines that the cable temperature is abnormal, it will control the power supply switch S6 to disconnect, and send a disconnection signal to the controlled end of the first non-powered weakly-conductive switch S3 through the first configuration control port C_S3 to control the first non-powered weakly-conductive switch S3 to disconnect. Subsequently, the first cable plug PLUG-A will stop supplying power externally. When the control module 2 loses power, the first non-powered weakly-conductive switch S3 automatically resumes the weakly-conductive state from the disconnected state. Subsequently, the Source end and the Sink end will perform a reconnection detection. When it is determined that the Source end and the Sink end are in a connected state, the Source end will re-power the control module 2 through VBUS1 and the voltage stabilization power supply module LDO. The control module 2 will continue to detect the cable temperature after power-on. If it is determined that the cable is over-temperature, the control module 2 can perform one of the following operations: 1. Control the power supply switch S6 to remain in the disconnected state and not supply power to the Sink end; 2. Control the first non-powered weakly-conductive switch S3 to disconnect, control the grounding switch S5 and the first pull-up switch S4 to close, ensuring that the cable exposes a grounding resistance Rd to the Source end and a first pull-up resistance Rp-B to the Sink end, ensuring that the Source end can provide an output to VBUS to ensure that the control module 2 has power, and provide a low-level voltage (such as 5V) to the Sink end through VBUS1. When the control module 2 determines that the Source end provides a low-level voltage, it controls the power supply switch S6 to close, and the low-level voltage provided by the Source end is transmitted to the Sink end through the power supply switch S6. This can not only make the temperature rise rate of the cable much smaller than the temperature drop rate, so that the overall temperature of the cable no longer rises, but also continue to supply power to the Sink end.

[0037] Further, the circuit further includes a first voltage comparison module 4. The first input end of the first voltage comparison module 4 is connected to the power bus port VBUS1 of the first cable plug PLUG-A, the second input end of the first voltage comparison module 4 is connected to the output end of the voltage stabilization power supply module LDO, and the output end of the first voltage comparison module 4 is connected to the first receiving port VBUSA of the control module 2;

[0038] Controlling the power supply switch S6 to close when the low-level voltage is output at the power bus port VBUS1 of the first cable plug PLUG-A includes: when it is determined according to the signal received by the first receiving port VBUSA that the low-level voltage is output at the power bus port VBUS1 of the first cable plug PLUG-A, controlling the power supply switch S6 to close.

[0039] Specifically, the two input terminals of the first voltage comparison module 4 are respectively connected to the power bus port VBUS1 of the first cable plug PLUG-A and the output terminal of the voltage regulator power supply module LDO. When the cable temperature is too high, the input voltages of the two input terminals are compared, and the comparison result is output to the first receiving port VBUSA of the control module 2. The control module 2 analyzes the data received by the first receiving port VBUSA to determine whether the voltage output by the power bus port VBUS1 of the first cable plug PLUG-A is a low-level voltage. If so, the power supply switch S6 is controlled to close through the power supply control port C_S6, so that the first cable plug PLUG-A provides a low-level voltage to the second cable plug PLUG-B. If not, the power supply switch S6 remains in the off state.

[0040] Exemplarily, as Figure 3 shown, it is assumed that the first voltage comparison module 4 includes a first operational amplifier U_VBUS1, a first feedback resistor R7, a first voltage dividing resistor R8, a second feedback resistor R3, and a second voltage dividing resistor R4. The first end of the first feedback resistor R7 is connected to the power bus port VBUS1 of the first cable plug PLUG-A, and the second end of the first feedback resistor R7 is respectively connected to the non-inverting input terminal of the first operational amplifier U_VBUS1 and the first end of the first voltage dividing resistor R8; the second end of the first voltage dividing resistor R8 is used for grounding; the output terminal of the first operational amplifier U_VBUS1 is connected to the first receiving port VBUSA of the control module 2; the first end of the second feedback resistor R3 is connected to the output terminal VCC of the voltage regulator power supply module LDO, and the second end of the second feedback resistor R3 is respectively connected to the inverting input terminal of the first operational amplifier U_VBUS1 and the first end of the second voltage dividing resistor R4; the second end of the second voltage dividing resistor R4 is used for grounding. The voltage input to the inverting input terminal of the first operational amplifier U_VBUS1 is about 5.5V, and the low-level voltage is about 5V.

[0041] In a preferred embodiment, the controlled end of the non-powered weak conduction module 1 is connected to the configuration control port of the control module 2; the control module 2 is further configured to: after sending the normal power supply signal to the controlled end of the power supply switch S6 through the power supply control port C_S6, send a strong conduction signal to the controlled end of the non-powered weak conduction module 1 through the configuration control port to control the non-powered weak conduction module 1 to be in a strong conduction state.

[0042] Specifically, the non-powered weak conduction module 1 further has a controlled end, which is connected to the configuration control port of the control module 2. When the control module 2 determines that the cable temperature is normal, it controls the non-powered weak conduction module 1 to be in a strong conduction state, facilitating the subsequent passage of PD message communication signals, where the full Chinese name of PD is the Power Delivery protocol message, and the full English name is Power Delivery.

[0043] In a preferred embodiment, as Figure 4 shown, on the basis of the Figure 1 circuit, the circuit further includes a first unidirectional conduction module D1 and a second unidirectional conduction module D2;

[0044] The voltage regulator power supply module LDO, whose input end is used to be connected to the power bus port VBUS1 of the first cable plug PLUG-A, and whose output end is connected to the power bus port VCC' of the control module 2, includes:

[0045] The input end of the first unidirectional conduction module D1 is used to be connected to the power bus port VBUS1 of the first cable plug PLUG-A, the output end of the first unidirectional conduction module D1 is connected to the input end of the voltage regulator power supply module LDO, and the output end of the voltage regulator power supply module LDO is connected to the power bus port VCC' of the control module 2; wherein, one of the first cable plug PLUG-A and the second cable plug PLUG-B is used to connect to the power supply device, and the other is used to connect to the power receiving device.

[0046] Specifically, assuming that the first unidirectional conduction module D1 and the second unidirectional conduction module D2 are diodes, in this embodiment, the power supply device can be the first cable plug PLUG-A or the second cable plug PLUG-B. When the power supply device is the first cable plug PLUG-A, the power bus port VBUS1 of the first cable plug PLUG-A outputs voltage, which is transmitted to the voltage regulator power supply module LDO through the first unidirectional conduction module D1, and the voltage regulator power supply module LDO provides a stable voltage for the control module 2. When the power supply device is the second cable plug PLUG-B, the power bus port VBUS2 of the second cable plug PLUG-B outputs voltage, which is transmitted to the voltage regulator power supply module LDO through the second unidirectional conduction module D2, and the voltage regulator power supply module LDO provides a stable voltage for the control module 2.

[0047] Furthermore, as Figure 5As shown, the non-electroweak conduction module 1 includes a first non-electroweak conduction switch S3 and a second non-electroweak conduction switch S2. The first end of the second non-electroweak conduction switch S2 is respectively used to connect to the configuration channel port CCA of the first cable plug PLUG-A and the first end of the second pull-up module. The second end of the second non-electroweak conduction switch S2 is respectively connected to the first end of the first non-electroweak conduction switch S3, the power supply orientation detection module 3, and the first end of the grounding module. The first end of the first non-electroweak conduction switch S3 is also respectively connected to the power supply orientation detection module 3 and the first end of the grounding module. The second end of the first non-electroweak conduction switch S3 is used to respectively connect to the first end of the first pull-up module and the configuration channel port CCB of the second cable plug PLUG-B;

[0048] The circuit further includes the first pull-up module, the second pull-up module, the grounding module, and the power supply orientation detection module 3. The grounding module includes a series-connected grounding resistor Rd and a grounding switch S5. The second end of the grounding module is used for grounding. The controlled end of the grounding resistor Rd is connected to the grounding control port C_S5 of the control module 2. The first pull-up module includes a series-connected first pull-up resistor Rp-B and a first pull-up switch S4. The second end of the first pull-up module is connected to the output end of the voltage regulator power supply module LDO. The controlled end of the first pull-up switch S4 is connected to the first pull-up control port C_S4 of the control module 2. The second pull-up module includes a series-connected second pull-up resistor Rp-A and a second pull-up switch S1. The second end of the second pull-up module is connected to the output end of the voltage regulator power supply module LDO. The controlled end of the second pull-up switch S1 is connected to the second pull-up control port C_S1 of the control module 2. The first input end of the power supply orientation detection module 3 is respectively connected to the first end of the first non-electroweak conduction switch S3 and the second end of the second non-electroweak conduction switch S2. The second input end of the power supply orientation detection module 3 is connected to the output end of the voltage regulator power supply module LDO. The output end of the power supply orientation detection module 3 is connected to the orientation signal receiving port COMP_CC of the control module 2.

[0049] Specifically, in this embodiment, the non-powered weak conduction module 1 includes a first non-powered weak conduction switch S3 and a second non-powered weak conduction switch S2. The circuit further includes the first pull-up module, the second pull-up module, the grounding module, and the power supply orientation detection module 3. Among them, the first input end of the power supply orientation detection module 3 is connected between the connection lines of the first non-powered weak conduction switch S3 and the second non-powered weak conduction switch S2. The control module 2 determines which of the first cable plug PLUG-A and the second cable plug PLUG-B is the power supply device and which is the powered device by controlling the on-off states of the grounding switch S5, the first non-powered weak conduction switch S3, and the first non-powered weak conduction switch S3 and collecting the output of the power supply orientation detection module 3. After identifying the power supply device, when the control module 2 determines that the cable temperature is abnormal, it can control the on-off of the grounding switch S5, the second pull-up switch S1, and the first pull-up switch S4 to make the power supply device output a low-level voltage, and control the power supply switch S6 to close, so that the power supply device provides a low-level voltage for the powered device.

[0050] Further, as Figure 5 shown, the controlled end of the first non-powered weak conduction switch S3 is connected to the first configuration control port C_S3 of the control module 2, and the controlled end of the second non-powered weak conduction switch S2 is connected to the second configuration control port C_S2 of the control module 2. The control module 2 is further configured to:

[0051] When sending the over-temperature protection signal to the controlled end of the power supply switch S6 through the power supply control port C_S6, send disconnection signals to the controlled ends of the first non-powered weak conduction switch S3 and the second non-powered weak conduction switch S2 through the first configuration control port C_S3 and the second configuration control port C_S2 respectively, so as to control the first non-powered weak conduction switch S3 and the second non-powered weak conduction switch S2 to disconnect;

[0052] After the first non-powered weak conduction switch S3 and the second non-powered weak conduction switch S2 automatically resume the weak conduction state from the disconnected state, if it is determined that the cable is over-temperature and the first device connected to the first cable plug PLUG-A is the power supply device, send a disconnection signal to the controlled end of the first non-powered weak conduction switch S3 through the first configuration control port C_S3, send a closing signal to the controlled end of the first pull-up switch S4 through the first pull-up control port C_S4, send a closing signal to the controlled end of the grounding switch S5 through the grounding control port C_S5, and send a closing signal to the controlled end of the second non-powered weak conduction switch S2 through the second configuration control port C_S2, so as to control the first non-powered weak conduction switch S3 to disconnect, the second non-powered weak conduction switch S2, the first pull-up switch S4, and the grounding switch S5 to close;

[0053] After the first non-powered weak conduction switch S3 and the second non-powered weak conduction switch S2 automatically resume the weak conduction state from the off state, if it is determined that the cable is overheated and the second device connected to the second cable plug PLUG-B is the power supply device, the disconnect signal is sent to the controlled end of the second non-powered weak conduction switch S2 through the second configuration control port C_S2, the close signal is sent to the controlled end of the second pull-up switch S1 through the second pull-up control port C_S1, the close signal is sent to the controlled end of the ground switch S5 through the ground control port C_S5, and the close signal is sent to the controlled end of the first non-powered weak conduction switch S3 through the first configuration control port C_S3, so as to control the second non-powered weak conduction switch S2 to disconnect, and the first non-powered weak conduction switch S3, the second pull-up switch S1 and the ground switch S5 to close.

[0054] The first device connected to the first cable plug PLUG-A is used to output a low-level voltage through the power bus port of the first cable plug PLUG-A when the first non-powered weak conduction switch S3 is in the off state, the second non-powered weak conduction switch S2, the first pull-up switch S4 and the ground switch S5 are in the on state; or, the second device connected to the second cable plug PLUG-B is used to output a low-level voltage through the power bus port of the second cable plug PLUG-B when the second non-powered weak conduction switch S2 is in the off state, the first non-powered weak conduction switch S3, the second pull-up switch S1 and the ground switch S5 are in the on state.

[0055] The control module 2 is further configured to: control the power supply switch S6 to close when the power bus port of the power supply device outputs the low-level voltage.

[0056] Specifically, the working principle of the cable over-temperature protection circuit further includes: when the control module 2 determines that the cable temperature is abnormal, it controls the power supply switch S6, the first non-powered weak conduction switch S3, the second non-powered weak conduction switch S2, the first pull-up switch S4, the second pull-up switch S1, and the grounding switch S5 to disconnect, the power supply device stops supplying power externally, the control module 2 loses power, the first non-powered weak conduction switch S3 and the second non-powered weak conduction switch S2 automatically resume the weak conduction state from the disconnected state. Then, the power supply device and the power-receiving device re-determine the connection relationship, the power supply device supplies power to the control module 2. After the control module 2 is re-powered on, if it determines that the power supply device is on the PLUG-A side of the first cable plug and the cable temperature is abnormal, it controls the first non-powered weak conduction switch S3 to disconnect, the second non-powered weak conduction switch S2, the first pull-up switch S4, and the grounding switch S5 to close; if it determines that the power supply device is on the PLUG-B side of the second cable plug and the cable temperature is abnormal, it controls the second non-powered weak conduction switch S2 to disconnect, the first non-powered weak conduction switch S3, the second pull-up switch S1, and the grounding switch S5 to close. After performing the above operations, the power bus port of the power supply device outputs a low-level voltage, and the control module 2 controls the power supply switch S6 to close, and transmits the low-level voltage output by the power bus port of the power supply device to the power-receiving device.

[0057] Further, as Figure 6 shown, the circuit further includes a first voltage comparison module 4 and a second voltage comparison module 5; the first input terminal of the first voltage comparison module 4 is connected to the power bus port VBUS1 of the first cable plug PLUG-A, the second input terminal of the first voltage comparison module 4 is connected to the output terminal of the voltage stabilization power supply module LDO, and the output terminal of the first voltage comparison module 4 is connected to the first receiving port VBUSA of the control module 2; the first input terminal of the second voltage comparison module 5 is connected to the power bus port VBUS2 of the second cable plug PLUG-B, the second input terminal of the second voltage comparison module 5 is connected to the output terminal of the voltage stabilization power supply module LDO, and the output terminal of the second voltage comparison module 5 is connected to the second receiving port VBUSB of the control module 2;

[0058] When the power bus port of the power supply device outputs the low-level voltage, controlling the power supply switch S6 to close includes: when it is determined according to the signals received by the first receiving port VBUSA and the second receiving port VBUSB that the power bus port of the power supply device outputs the low-level voltage, controlling the power supply switch S6 to close.

[0059] Specifically, in this embodiment, a first voltage comparison module 4 and a second voltage comparison module 5 are added to the circuit. Two input terminals of the first voltage comparison module 4 are respectively connected to the power bus port VBUS1 of the first cable plug PLUG-A and the output terminal of the voltage regulator power supply module LDO, and are used to compare the voltage at the power bus port VBUS1 of the first cable plug PLUG-A with the voltage at the output terminal of the voltage regulator power supply module LDO. Two input terminals of the second voltage comparison module 5 are respectively connected to the power bus port VBUS2 of the second cable plug PLUG-B and the output terminal of the voltage regulator power supply module LDO, and are used to compare the voltage at the power bus port VBUS2 of the second cable plug PLUG-B with the voltage at the output terminal of the voltage regulator power supply module LDO. Whether the power supply device outputs a low-level voltage is determined according to the two comparison results. When the control device determines that the power supply device outputs a low-level voltage, it controls the power supply switch S6 to close, and the power supply device provides low-voltage power supply service for the power receiving device.

[0060] Further, as Figure 7 shown, the first voltage comparison module 4 includes a first operational amplifier U_VBUS1, a first feedback resistor R7, a first voltage-dividing resistor R8, a second feedback resistor R3, and a second voltage-dividing resistor R4. The second voltage comparison module 5 includes a second operational amplifier U_VBUS2, a third feedback resistor R9, a third voltage-dividing resistor R10, a fourth feedback resistor R5, and a fourth voltage-dividing resistor R6;

[0061] The first end of the first feedback resistor R7 is connected to the power bus port VBUS1 of the first cable plug PLUG-A. The second end of the first feedback resistor R7 is respectively connected to the non-inverting input terminal of the first operational amplifier U_VBUS1 and the first end of the first voltage-dividing resistor R8. The second end of the first voltage-dividing resistor R8 is used for grounding. The output terminal of the first operational amplifier U_VBUS1 is connected to the first receiving port VBUSA of the control module 2. The first end of the second feedback resistor R3 is connected to the output terminal of the voltage regulator power supply module LDO. The second end of the second feedback resistor R3 is respectively connected to the inverting input terminal of the first operational amplifier U_VBUS1 and the first end of the second voltage-dividing resistor R4. The second end of the second voltage-dividing resistor R4 is used for grounding;

[0062] The first end of the third feedback resistor R9 is connected to the power bus port VBUS2 of the second cable plug PLUG-B. The second end of the third feedback resistor R9 is respectively connected to the non-inverting input terminal of the second operational amplifier U_VBUS2 and the first end of the third voltage-dividing resistor R10. The second end of the third voltage-dividing resistor R10 is used for grounding. The output terminal of the second operational amplifier U_VBUS2 is connected to the second receiving port VBUSB of the control module 2. The first end of the fourth feedback resistor R5 is connected to the output terminal of the voltage regulator power supply module LDO. The second end of the fourth feedback resistor R5 is respectively connected to the inverting input terminal of the second operational amplifier U_VBUS2 and the first end of the fourth voltage-dividing resistor R6. The second end of the fourth voltage-dividing resistor R6 is used for grounding.

[0063] Specifically, an operational amplifier is a direct-coupled multi-stage amplifier circuit with a very high voltage amplification factor and is widely used in electronic circuits. In this embodiment, the voltage comparison function of the operational amplifier is utilized to compare the output voltages of the first cable plug PLUG-A and the second cable plug PLUG-B with the output voltage of the voltage regulator power supply module LDO respectively. If the output results of the first voltage comparison module 4 and the second voltage comparison module 5 are both 0, it indicates that the output voltage of the power supply device is within the safe range and is a low-level voltage.

[0064] In a preferred implementation manner, as Figure 8 shown, on the basis of Figure 5 the power supply orientation detection module 3 includes a third operational amplifier U_CC, a fifth feedback resistor R1, and a fifth voltage-dividing resistor R2. The non-inverting input terminal of the third operational amplifier U_CC is respectively connected to the first end of the first non-powered weak conduction switch S3 and the second end of the second non-powered weak conduction switch S2. The output terminal of the third operational amplifier U_CC is connected to the orientation signal receiving port COMP_CC of the control module 2. The inverting input terminal of the third operational amplifier U_CC is respectively connected to the second end of the fifth feedback resistor R1 and the first end of the fifth voltage-dividing resistor R2. The first end of the fifth feedback resistor R1 is used for connecting to the output terminal of the voltage regulator power supply module LDO. The second end of the fifth voltage-dividing resistor R2 is used for grounding.

[0065] The control module 2 is further configured to determine the power supply device in the following manner:

[0066] Control the second non-powered weak conduction switch S2 and the grounding switch S5 to be closed, and control the first non-powered weak conduction switch S3 to be open, or control the first non-powered weak conduction switch S3 and the grounding switch S5 to be closed, and control the second non-powered weak conduction switch S2 to be open.

[0067] Receive the output signal of the third operational amplifier U_CC, and determine whether the power supply device is the first device connected to the first cable plug PLUG-A or the second device connected to the second cable plug PLUG-B according to the output signal of the third operational amplifier U_CC.

[0068] Specifically, the detection of the left and right side positions of the power supply device on the cable is because the cable has two Type-C connectors, and it is impossible to know in advance which end is connected to the power supply device. Therefore, in this embodiment, a power supply position detection module 3 including a third operational amplifier U_CC, a fifth feedback resistor R1, and a fifth voltage-dividing resistor R2 is provided in the circuit. First, try to close the second non-powered weak conduction switch S2 and the grounding switch S5, and open the first non-powered weak conduction switch S3, and detect the output result of the third operational amplifier U_CC. If the output result is 1, it means that the Plug-A side is the power supply device; if the output is 0, it means that the Plug-B side is the power supply device.

[0069] To facilitate understanding of the structure and working principle of the circuit, the following uses a specific example to introduce the circuit structure and working process. Please refer to Figure 9 The structural schematic diagram of the cable over-temperature protection circuit shown. The circuit uses six switches: a second pull-up switch S1, a second non-powered weak conduction switch S2, a first non-powered weak conduction switch S3, a first pull-up switch S4, a grounding switch S5, and a power supply switch S6; fourteen resistors: a second pull-up resistor Rp-A, a first pull-up resistor Rp-B, a grounding resistor Rd, a fifth feedback resistor R1, a fifth voltage-dividing resistor R2, a second feedback resistor R3, a second voltage-dividing resistor R4, a fourth feedback resistor R5, a fourth voltage-dividing resistor R6, a thermistor Rntc, a first feedback resistor R7, a first voltage-dividing resistor R8, a third feedback resistor R9, and a fifth feedback resistor third voltage-dividing resistor R10; two diodes: a first unidirectional conduction module D1 and a second unidirectional conduction module D2; a control module 2 (i.e., the control module 2); a voltage regulator power supply module LDO (such as a low-dropout linear regulator); three comparators: a third operational amplifier U_CC, a first operational amplifier U_VBUS1, and a second operational amplifier U_VBUS2.

[0070] As Figure 9 shown, the connection logic of the circuit provided by the embodiment of the present invention is as follows:

[0071] 1. The first end of the power supply switch S6 is connected to the power bus port VBUS1 of the first cable plug PLUG-A, the second end of the power supply switch S6 is connected to the VBUS of the PLUG-B plug, and the controlled end of the power supply switch S6 is connected to the power supply control port C_S6 of the control module 2.

[0072] 2. The input terminal of the first unidirectional conduction module D1 is connected to the first terminal of the power supply switch S6, and the output terminal is connected to the input terminal of the voltage regulator power supply module LDO; the input terminal of the second unidirectional conduction module D2 is connected to the second terminal of the power supply switch S6, and the output terminal is connected to the input terminal of the voltage regulator power supply module LDO.

[0073] 3. The first terminal of the first feedback resistor R7 is connected to the first terminal of the power supply switch S6. The first terminal of the first voltage dividing resistor R8 is connected to the second terminal of the first feedback resistor R7 and is connected to the + terminal of the first operational amplifier U_VBUS1. The second terminal of the first voltage dividing resistor R8 is grounded. The first terminal of the second feedback resistor R3 is connected to the output terminal VCC of the voltage regulator power supply module LDO. The second terminal of the second feedback resistor R3 is connected to the first terminal of the second voltage dividing resistor R4 and is connected to the - terminal of the first operational amplifier U_VBUS1. The second terminal of the second voltage dividing resistor R4 is grounded. The O terminal of the first operational amplifier U_VBUS1 is connected to the first receiving port VBUSA of the control module 2.

[0074] 4. The first terminal of the third feedback resistor R9 is connected to the second terminal of the power supply switch S6. The first terminal of the third voltage dividing resistor R10 is connected to the second terminal of the third feedback resistor R9 and is connected to the + terminal of the second operational amplifier U_VBUS2. The second terminal of the third voltage dividing resistor R10 is grounded. The first terminal of the fourth feedback resistor R5 is connected to the output terminal VCC of the voltage regulator power supply module LDO. The second terminal of the fourth feedback resistor R5 is connected to the first terminal of the fourth voltage dividing resistor R6 and is connected to the - terminal of the second operational amplifier U_VBUS2. The second terminal of the fourth voltage dividing resistor R6 is grounded. The O terminal of the second operational amplifier U_VBUS2 is connected to the second receiving port VBUSB of the control module 2.

[0075] 5. The first terminal of the thermistor Rntc is connected to the temperature monitoring port NTC of the control module 2, and the second terminal of the thermistor Rntc is grounded.

[0076] 6. The second terminal of the second non-powered weak conduction switch S2 is connected to the + terminal of the third operational amplifier U_CC. The first terminal of the fifth feedback resistor R1 is connected to the output terminal VCC of the LDO. The second terminal of the fifth feedback resistor R1 is connected to the first terminal of the fifth voltage dividing resistor R2 and is connected to the - terminal of the third operational amplifier U_CC. The second terminal of the fifth voltage dividing resistor R2 is grounded. The O terminal of the third operational amplifier U_CC is connected to the azimuth signal receiving port COMP_CC of the control module 2.

[0077] 7. The first end of the second pull-up resistor Rp-A is connected to the output terminal VCC of the voltage regulator power supply module LDO. The second end of the second pull-up resistor Rp-A is connected to the first end of the second pull-up switch S1. The controlled terminal of the second pull-up switch S1 is connected to the second pull-up control port C_S1 of the control module 2. The second end of the second pull-up switch S1 is connected to the first end of the second non-powered weak conduction switch S2 and is also connected to the CCA of the first cable plug PLUG-A. The controlled terminal of the second non-powered weak conduction switch S2 is connected to the second configuration control port C_S2 of the control module 2. The second end of the second non-powered weak conduction switch S2 is connected to the first end of the first non-powered weak conduction switch S3. The controlled terminal of the first non-powered weak conduction switch S3 is connected to the first configuration control port C_S3 of the control module 2. The second end of the first non-powered weak conduction switch S3 is connected to the CCB of the second cable plug PLUG-B. The second end of the first pull-up switch S4 is connected to the second end of the first non-powered weak conduction switch S3. The controlled terminal of the first pull-up switch S4 is connected to the first pull-up control port C_S4 of the control module 2. The first end of the first pull-up switch S4 is connected to the second end of the first pull-up resistor Rp-B. The first end of the first pull-up resistor Rp-B is connected to the output terminal VCC of the voltage regulator power supply module LDO.

[0078] 8. The first end of the ground switch S5 is connected to the second end of the second non-powered weak conduction switch S2, the first end of the first non-powered weak conduction switch S3, and the + terminal of the third operational amplifier U_CC. The controlled terminal of the ground switch S5 is connected to the ground control port C_S5 of the control module 2. The second end of the ground switch S5 is connected to the first end of the ground resistor Rd. The second end of the ground resistor Rd is grounded.

[0079] The working principle of the cable over-temperature protection circuit is as follows:

[0080] The second no-power weak-conduction switch S2 and the first no-power weak-conduction switch S3 are in weak conduction when the cable is without power. Therefore, in the case where the control module 2 has no power supply, the configuration channel signal (Configuration Channel, CC) at the Source end can reach the Sink end through the second no-power weak-conduction switch S2 and the first no-power weak-conduction switch S3, thereby completing the connection detection of Type-C. Then, the Source end inputs through the VBUS path to the voltage regulator power supply module LDO to start power supply to the control module 2. After the control module 2 is powered on, it will first detect the temperature. If the temperature is normal, it will turn on the power supply switch S6 to allow the Source end to supply normal power to the Sink end. The second no-power weak-conduction switch S2 and the first no-power weak-conduction switch S3 give clear control signals to close, enabling the CCA and CCB signals to pass directly, that is, the second no-power weak-conduction switch S2 and the first no-power weak-conduction switch S3 are in strong conduction state, facilitating the subsequent passage of PD message communication signals. The second pull-up switch S1, the first pull-up switch S4, and the ground switch S5 are turned off without performing any resistance pull-up and pull-down processing on the channel between CCA and CCB; if the temperature is abnormal, the power supply switch S6 will remain closed, prohibiting the Source end from directly supplying power to the Sink end (or after determining the left or right side position of the Source end on the cable, the corresponding pull-up resistor (second pull-up resistor Rp-A / first pull-up resistor Rp-B) and pull-down (ground resistor Rd) resistor are turned on, and when it is determined that the VBUS voltage (i.e., the voltage output by the power supply device) is within the safe 5V range, the power supply switch S6 is turned on to allow the Source end to supply power to the Sink end through VBUS).

[0081] When the temperature of the cable reaches the protection threshold during normal operation, the second pull-up switch S1, the second non-powered weak conduction switch S2, the first non-powered weak conduction switch S3, the first pull-up switch S4, the ground switch S5, and the power supply switch S6 will all be disconnected, which can disconnect the power supply from the Source end to the Sink end to achieve temperature protection. At the same time, since the second pull-up switch S1, the second non-powered weak conduction switch S2, the first non-powered weak conduction switch S3, the first pull-up switch S4, the ground switch S5, and the power supply switch S6 are all disconnected, the Source end will turn off VBUS and stop supplying power to the control module 2 (this is the first protection action taken when the temperature anomaly is just detected. After the Source end turns off the power bus port and stops supplying power to the control module 2, since the second non-powered weak conduction switch S2 and the first non-powered weak conduction switch S3 can directly connect CCA and CCB in the power-off state, the Source end will re-provide the VBUS voltage to the control module 2 according to the Type-C protocol definition. However, if the cable temperature is still too high at this time, the corresponding pull-up (second pull-up resistor Rp-A / first pull-up resistor Rp-B) and pull-down (ground resistor Rd) resistors will be turned on after determining the left or right side position of the Source end on the cable as described above, and when it is determined that the VBUS voltage is within the safe 5V range, the power supply switch S6 will be turned on to allow the Source end to supply power to the Sink end), and the Type-C connection detection with the Sink end will be re-implemented. Since the cable temperature will not drop immediately, after the Source end and the Sink end are re-connected, the control module 2 will be powered again. When the cable control module 2 is powered, it will first detect the temperature. If the temperature is normal, the power supply switch S6 will be closed, and the Source end will supply power to the Sink end normally. If the temperature is too high, the power supply switch S6 will remain closed, or the corresponding pull-up resistor and ground resistor will be controlled after determining the left or right side position of the Source end, and the power supply switch S6 will be turned on only when it is determined that the VBUS voltage is within the safe 5V range to supply power to the Sink end safely at 5V. This ensures that when the cable temperature is abnormal, the Source end does not supply the normal VBUS power to the Sink end or provides a safe 5V power supply.

[0082] When the cable is under temperature protection (when the temperature is detected to be abnormal at the beginning, after the second non-powered weak conduction switch S2 and the first non-powered weak conduction switch S3 are turned off, the Source end will actively turn off the VBUS output according to the Type-C protocol. After the VBUS output is turned off, the entire cable circuit will lose power. However, since the second non-powered weak conduction switch S2 and the first non-powered weak conduction switch S3 can directly connect the CCA and CCB signals in the power-off state, according to the Type-C protocol, the Source end will detect the Sink end again (if the Sink end is not unplugged) and provide VBUS voltage output. At this time, for the cable, it is the initial power-on. But when initially powered on, the temperature will continue to be detected. If the temperature is still too high, it is determined to be under temperature protection) (the power supply switch S6 is turned off to stop the Source end from supplying power to the Sink end or only supply power to the Sink end with a 5V safe voltage), and after detecting that the cable temperature has returned to the normal range, the second pull-up switch S1, the second non-powered weak conduction switch S2, the first non-powered weak conduction switch S3, the first pull-up switch S4, the grounding switch S5, and the power supply switch S6 will all be disconnected. Since the second pull-up switch S1, the second non-powered weak conduction switch S2, the first non-powered weak conduction switch S3, the first pull-up switch S4, the grounding switch S5, and the power supply switch S6 are all disconnected, the Source end will turn off the VBUS and stop supplying power to the cable control module 2, and re-perform the Type-C connection detection with the Sink end. Since the temperature has returned to the normal range, after the connection detection is completed again, when the control module 2 is powered on again, the cable will be in a normal working state, allowing the Source end to supply power to the Sink end normally.

[0083] The detection of the position of the Source end on the left and right sides of the cable is because the cable has two Type-C connectors, and it is impossible to know in advance which end is connected to the Source end. When protection occurs, if the Source end is connected to the PLUG-A end of the first cable plug, the second non-powered weak conduction switch S2 and the ground switch S5 need to be closed, and the first non-powered weak conduction switch S3 needs to be opened, ensuring that the cable exposes a grounding resistance Rd to the ground for the Source end, ensuring that the Source end can normally provide the VBUS voltage to ensure that the control module 2 of the cable is powered. If a safe 5V VBUS voltage needs to be provided to the Sink end during protection, the first pull-up switch S4 needs to be closed simultaneously to expose a pull-up resistance to the Sink end; when protection occurs, if the Source end is connected to the PLUG-B end of the second cable plug, the first non-powered weak conduction switch S3 and the ground switch S5 need to be closed, and the second non-powered weak conduction switch S2 needs to be opened, ensuring that the cable exposes a grounding resistance Rd to the ground for the Source end, ensuring that the Source end can normally provide the VBUS voltage to ensure that the control module 2 is powered. If a safe 5V VBUS voltage needs to be provided to the Sink end during protection, the second pull-up switch S1 needs to be closed simultaneously to expose a pull-up resistance to the Sink end.

[0084] The method for detecting the position of the Source end on the left and right sides of the cable is as follows: First, try to close the second non-powered weak conduction switch S2 and the ground switch S5, and open the first non-powered weak conduction switch S3, and detect the output result of the third operational amplifier U_CC. If the output is 1, it means that the PLUG-A end of the first cable plug is connected to the Source end. If the output is 0, it means that the PLUG-B end of the second cable plug is connected to the Source end.

[0085] The method for judging whether the VBUS voltage is within the safe 5V range is as follows: Detect the output results of the first operational amplifier U_VBUS1 and the second operational amplifier U_VBUS2. If the output results of both comparators are 0, it means that it is within the safe 5V range. The positive terminal input of the first operational amplifier U_VBUS1 samples the VBUS1 voltage of the PLUG-A end of the first cable plug through the first feedback resistor R7 and the first voltage-dividing resistor R8. The negative terminal input of the first operational amplifier U_VBUS1 generates a comparison reference voltage by comparing the voltage division of the second feedback resistor R3 and the second voltage-dividing resistor R4 with the output of the voltage regulator power supply module LDO; the positive terminal input of the second operational amplifier U_VBUS2 samples the VBUS2 voltage of the PLUG-B end of the second cable plug through the third feedback resistor R9 and the fifth feedback resistor and the third voltage-dividing resistor R10. The negative terminal input of the second operational amplifier U_VBUS2 generates a comparison reference voltage by comparing the voltage division of the fourth feedback resistor R5 and the fourth voltage-dividing resistor R6 with the output of the voltage regulator power supply module LDO.

[0086] Compared with the prior art, the embodiment of the present invention provides a cable over-temperature protection circuit, which includes a non-powered weak conduction module 1, a voltage stabilizing power supply module LDO, a control module 2, and a power supply switch S6. Both ends of the non-powered weak conduction module 1 are used to be connected to the configuration channel port CCB of the first cable plug PLUG-A and the second cable plug PLUG-B to realize connection detection between two devices so that the power supply device can supply power. The input end and the output end of the voltage stabilizing power supply module LDO are respectively used to be connected to the power bus port VBUS1 of the first cable plug PLUG-A and the power bus port VCC' of the control module 2, and the grounding end of the voltage stabilizing power supply module LDO is used for grounding. The first cable plug PLUG-A supplies power to the control module 2 through the voltage stabilizing power supply module LDO. The temperature monitoring port NTC of the control module 2 is used to receive the temperature signal of the cable, and the power supply control port C_S6 is connected to the controlled end of the power supply switch S6 arranged between the power bus port VBUS1 of the first cable plug PLUG-A and the power bus port VBUS2 of the second cable plug PLUG-B. In the embodiment of the present invention, the control module 2 is used to send a normal power supply signal to the controlled end of the power supply switch S6 through the power supply control port C_S6 when it is determined that the cable temperature is normal according to the temperature signal, and send an over-temperature protection signal to the controlled end of the power supply switch S6 through the power supply control port C_S6 when it is determined that the cable is over-temperature, so as to control the power supply switch S6 to disconnect. Using the cable over-temperature protection circuit can avoid the phenomenon of alternating power on and off during the over-temperature protection of the cable and extend the service life of the device port.

[0087] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications are also regarded as the protection scope of the present invention.

Claims

1. A cable over-temperature protection circuit, characterized in that: include: A non-power weak conduction module, wherein the first end is used to connect to the configuration channel port of the first cable plug, and the second end is used to connect to the configuration channel port of the second cable plug; wherein the non-power weak conduction module is in a weak conduction state when there is no power; A voltage-stabilized power supply module, whose input end is used to be connected to the power bus port of the first cable plug, and whose output end is connected to the power bus port of the control module; The control module, whose temperature monitoring port is used to receive a temperature signal about the cable, and whose power supply control port is connected to the controlled end of the power supply switch; wherein the control module is used to send an over-temperature protection signal to the controlled end of the power supply switch through the power supply control port when it is determined that the cable is over-temperature according to the temperature signal, so as to control the power supply switch to be disconnected; the control module is also used to send a normal power supply signal to the controlled end of the power supply switch through the power supply control port when it is determined that the cable temperature is normal according to the temperature signal, so as to control the power supply switch to be closed; The power switch has a first end for connecting to the power bus port of the first cable plug, and a second end for connecting to the power bus port of the second cable plug.

2. The cable over-temperature protection circuit according to claim 1, characterized in that: The non-electrical weak conduction module comprises a first non-electrical weak conduction switch, wherein a first end of the first non-electrical weak conduction switch is respectively connected to a first end of the non-electrical weak conduction module and a first end of a grounding module, a second end of the first non-electrical weak conduction switch is respectively connected to a second end of the non-electrical weak conduction module and a first end of a first pull-up module, and a controlled end of the first non-electrical weak conduction switch is connected to a first configuration control port of the control module; The circuit further includes the grounding module and the first pull-up module; The grounding module comprises a grounding resistor and a grounding switch connected in series, the second end of the grounding module is used for grounding, and the controlled end of the grounding resistor is connected to the grounding control port of the control module; the first pull-up module comprises a first pull-up resistor and a first pull-up switch connected in series, the second end of the first pull-up module is used for connecting the voltage-stabilized power supply module, and the controlled end of the first pull-up switch is connected to the first pull-up control port of the control module; Wherein, the control module is further used for: when sending the over-temperature protection signal to the controlled end of the power switch through the power supply control port, sending a disconnection signal to the controlled end of the first non-electric weak conduction switch through the first configuration control port to control the first non-electric weak conduction switch to disconnect; after the first non-electric weak conduction switch automatically restores the weak conduction state from the disconnected state, if it is determined that the cable is over-temperature, sending a disconnection signal to the controlled end of the first non-electric weak conduction switch through the first configuration control port, sending a closing signal to the controlled end of the first pull-up switch through the first pull-up control port, and sending a closing signal to the controlled end of the grounding switch through the grounding control port, so as to control the first non-electric weak conduction switch to disconnect and the first pull-up switch and the grounding switch to close; The first device connected to the first cable plug is used to output a low level voltage through the power bus port of the first cable plug when the first non-electrical weak conduction switch is in an open state and the first pull-up switch and the grounding switch are in a closed state; The control module is further configured to control the power switch to be closed when the power bus port of the first cable plug outputs the low level voltage.

3. The cable over-temperature protection circuit according to claim 2, characterized in that: The circuit further comprises a first voltage comparison module, wherein a first input end of the first voltage comparison module is connected to a power bus port of the first cable plug, a second input end of the first voltage comparison module is connected to an output end of the voltage-stabilized power supply module, and an output end of the first voltage comparison module is connected to a first receiving port of the control module; The controlling the power switch to close when the power bus port of the first cable plug outputs the low level voltage includes: controlling the power switch to close when it is determined according to a signal received by the first receiving port that the power bus port of the first cable plug outputs the low level voltage.

4. The cable over-temperature protection circuit according to claim 1, characterized in that: The controlled end of the non-electrical weak conduction module is connected to the configuration control port of the control module; The control module is also used to: after sending the normal power supply signal to the controlled end of the power switch through the power supply control port, send a strong conduction signal to the controlled end of the non-power weak conduction module through the configuration control port to control the non-power weak conduction module to be in a strong conduction state.

5. The cable over-temperature protection circuit according to claim 1, characterized in that: Also includes a first unidirectional conductive module and a second unidirectional conductive module; The voltage-stabilized power supply module, whose input end is used to be connected to the power bus port of the first cable plug, and whose output end is connected to the power bus port of the control module, includes: The input end of the first unidirectional conductive module is used to connect to the power bus port of the first cable plug, the output end of the first unidirectional conductive module is connected to the input end of the voltage-stabilized power supply module, and the output end of the voltage-stabilized power supply module is connected to the power bus port of the control module; wherein, one of the first cable plug and the second cable plug is used to connect to a power supply device, and the other is used to connect to a powered device.

6. The cable over-temperature protection circuit according to claim 5, characterized in that: The non-electrical weak conduction module includes a first non-electrical weak conduction switch and a second non-electrical weak conduction switch, wherein the first end of the second non-electrical weak conduction switch is respectively used to connect with the configuration channel port of the first cable plug and the first end of the second pull-up module, and the second end of the second non-electrical weak conduction switch is respectively connected with the first end of the first non-electrical weak conduction switch, the power supply position detection module, and the first end of the grounding module, and the first end of the first non-electrical weak conduction switch is also respectively connected with the power supply position detection module and the first end of the grounding module, and the second end of the first non-electrical weak conduction switch is respectively used to connect with the first end of the first pull-up module and the configuration channel port of the second cable plug; The circuit also includes the first pull-up module, the second pull-up module, the grounding module and the power supply position detection module; the grounding module includes a grounding resistor and a grounding switch connected in series, the second end of the grounding module is used for grounding, and the controlled end of the grounding resistor is connected to the grounding control port of the control module; the first pull-up module includes a first pull-up resistor and a first pull-up switch connected in series, the second end of the first pull-up module is connected to the output end of the voltage-stabilized power supply module, and the controlled end of the first pull-up switch is connected to the first pull-up control port of the control module; the second pull-up module includes a second pull-up resistor and a second pull-up switch connected in series, the second end of the second pull-up module is connected to the output end of the voltage-stabilized power supply module, and the controlled end of the second pull-up switch is connected to the second pull-up control port of the control module; the first input end of the power supply position detection module is respectively connected to the first end of the first non-electric weak conduction switch and the second end of the second non-electric weak conduction switch, the second input end of the power supply position detection module is connected to the output end of the voltage-stabilized power supply module, and the output end of the power supply position detection module is connected to the position signal receiving port of the control module.

7. The cable over-temperature protection circuit according to claim 6, characterized in that: The controlled end of the first non-electrical weak conduction switch is connected to the first configuration control port of the control module, and the controlled end of the second non-electrical weak conduction switch is connected to the second configuration control port of the control module, and the control module is further used for: When the over-temperature protection signal is sent to the controlled end of the power switch through the power supply control port, a disconnection signal is sent to the controlled ends of the first non-electrical weak conduction switch and the second non-electrical weak conduction switch through the first configuration control port and the second configuration control port respectively, so as to control the first non-electrical weak conduction switch and the second non-electrical weak conduction switch to be disconnected; After the first non-electrical weak conduction switch and the second non-electrical weak conduction switch automatically restore to a weak conduction state from a disconnected state, if it is determined that the cable is over-temperature and it is determined that the first device connected to the first cable plug is the power supply device, a disconnection signal is sent to the controlled end of the first non-electrical weak conduction switch through the first configuration control port, a closing signal is sent to the controlled end of the first pull-up switch through the first pull-up control port, a closing signal is sent to the controlled end of the grounding switch through the grounding control port, and a closing signal is sent to the controlled end of the second non-electrical weak conduction switch through the second configuration control port, so as to control the first non-electrical weak conduction switch to be disconnected, and the second non-electrical weak conduction switch, the first pull-up switch, and the grounding switch to be closed; After the first non-electrical weak conduction switch and the second non-electrical weak conduction switch automatically restore to a weak conduction state from a disconnected state, if it is determined that the cable is over-temperature and it is determined that the second device connected to the second cable plug is the power supply device, the disconnection signal is sent to the controlled end of the second non-electrical weak conduction switch through the second configuration control port, the closing signal is sent to the controlled end of the second pull-up switch through the second pull-up control port, the closing signal is sent to the controlled end of the grounding switch through the grounding control port, and the closing signal is sent to the controlled end of the first non-electrical weak conduction switch through the first configuration control port, so as to control the second non-electrical weak conduction switch to be disconnected and the first non-electrical weak conduction switch, the second pull-up switch and the grounding switch to be closed; The first device connected to the first cable plug is used to output a low level voltage through the power bus port of the first cable plug when the first non-electrical weak conduction switch is in an open state, and the second non-electrical weak conduction switch, the first pull-up switch, and the grounding switch are in a closed state; or the second device connected to the second cable plug is used to output a low level voltage through the power bus port of the second cable plug when the second non-electrical weak conduction switch is in an open state, and the first non-electrical weak conduction switch, the second pull-up switch, and the grounding switch are in a closed state; The control module is further used to control the power switch to close when the power bus port of the power supply device outputs the low level voltage.

8. The cable over-temperature protection circuit according to claim 7, characterized in that: It also includes a first voltage comparison module and a second voltage comparison module; the first input end of the first voltage comparison module is connected to the power bus port of the first cable plug, the second input end of the first voltage comparison module is connected to the output end of the voltage-stabilized power supply module, and the output end of the first voltage comparison module is connected to the first receiving port of the control module; the first input end of the second voltage comparison module is connected to the power bus port of the second cable plug, the second input end of the second voltage comparison module is connected to the output end of the voltage-stabilized power supply module, and the output end of the second voltage comparison module is connected to the second receiving port of the control module; When the power bus port of the power supply device outputs the low level voltage, controlling the power switch to close includes: when it is determined that the power bus port of the power supply device outputs the low level voltage based on signals received by the first receiving port and the second receiving port, controlling the power switch to close.

9. The cable over-temperature protection circuit according to claim 8, characterized in that: The first voltage comparison module includes a first operational amplifier, a first feedback resistor, a first voltage-dividing resistor, a second feedback resistor and a second voltage-dividing resistor, and the second voltage comparison module includes a second operational amplifier, a third feedback resistor, a third voltage-dividing resistor, a fourth feedback resistor and a fourth voltage-dividing resistor; The first end of the first feedback resistor is connected to the power bus port of the first cable plug, and the second end of the first feedback resistor is respectively connected to the in-phase input end of the first operational amplifier and the first end of the first voltage-dividing resistor; the second end of the first voltage-dividing resistor is used for grounding; the output end of the first operational amplifier is connected to the first receiving port of the control module; the first end of the second feedback resistor is connected to the output end of the voltage-stabilized power supply module, and the second end of the second feedback resistor is respectively connected to the inverting input end of the first operational amplifier and the first end of the second voltage-dividing resistor; the second end of the second voltage-dividing resistor is used for grounding; The first end of the third feedback resistor is connected to the power bus port of the second cable plug, and the second end of the third feedback resistor is respectively connected to the in-phase input end of the second operational amplifier and the first end of the third voltage-dividing resistor; the second end of the third voltage-dividing resistor is used for grounding; the output end of the second operational amplifier is connected to the second receiving port of the control module; the first end of the fourth feedback resistor is connected to the output end of the voltage-stabilized power supply module, and the second end of the fourth feedback resistor is respectively connected to the inverting input end of the second operational amplifier and the first end of the fourth voltage-dividing resistor; the second end of the fourth voltage-dividing resistor is used for grounding.

10. The cable over-temperature protection circuit according to claim 7, characterized in that: The power supply position detection module includes a third operational amplifier, a fifth feedback resistor and a fifth voltage-dividing resistor; the non-inverting input terminal of the third operational amplifier is respectively connected to the first end of the first non-electrical weak conduction switch and the second end of the second non-electrical weak conduction switch, the output terminal of the third operational amplifier is connected to the position signal receiving port of the control module, the inverting input terminal of the third operational amplifier is respectively connected to the second end of the fifth feedback resistor and the first end of the fifth voltage-dividing resistor, the first end of the fifth feedback resistor is used to be connected to the output end of the voltage-stabilized power supply module, and the second end of the fifth voltage-dividing resistor is used to be grounded; The control module is also used to determine the power supply device in the following manner: Control the second non-electrical weak conduction switch and the grounding switch to be closed, and control the first non-electrical weak conduction switch to be opened, or control the first non-electrical weak conduction switch and the grounding switch to be closed, and control the second non-electrical weak conduction switch to be opened, An output signal of the third operational amplifier is received, and according to the output signal of the third operational amplifier, it is determined that the power supply device is the first device connected to the first cable plug or the second device connected to the second cable plug.

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