CN111817409A - Fast charging protection circuit and method, fast charging chip, and fast charging power supply device - Google Patents

Abstract

The present application provides a fast charging protection circuit and method, a fast charging chip, and a fast charging power supply device. The fast charging protection circuit includes a voltage conversion module, a fast charging control module, and a plug-in detection module. The fast charging control module controls the voltage conversion module to output the corresponding fast charging voltage according to the fast charging protocol signal of the external device. The plug-in detection module outputs a pull-out signal when detecting that the fast-charging protocol signal disappears, wherein the fast-charging protocol signal disappears when the external device starts to be pulled out. The fast charging control module controls the voltage conversion module to reduce the output voltage to a preset voltage according to the pull-out signal. Among them, the time required from detecting the disappearance of the fast charging protocol signal to starting to reduce the output voltage is less than the time required for the external device to be pulled out from the beginning to being completely pulled out. In this way, the pull-out action of the external device can be detected in advance. And reduce the output voltage before the external device is completely unplugged, thereby effectively reducing the overshoot of the output voltage.

Description

Fast charging protection circuit and method, fast charging chip, and fast charging power supply device

technical field

The present application relates to the technical field of charging, and in particular, to a fast charging protection circuit and method, a fast charging chip, and a fast charging power supply device having the fast charging protection circuit or the fast charging chip.

Background technique

In recent years, with the development of fast charging technology, various fast charging technologies have become more and more widely used. Mobile terminals, such as mobile phones, tablet computers, etc., will apply for fast charging voltage to fast charging power supply devices with fast charging chips, such as fast charging mobile power supplies or fast charging adapters, through the fast charging protocol during fast charging. charging time. Taking a fast-charging mobile power supply with a fast-charging chip as an example, the current fast-charging mobile power supply can output voltages of different voltage levels such as 9V, 12V, and 15V according to the fast-charging protocol. For example, the QC protocol 2.0 can apply for a voltage of 9V or 12V, and the PD protocol can apply for a voltage of 9V, 12V, or 15V. When using the fast charging mobile power supply to charge the mobile terminal, if the mobile terminal is suddenly unplugged during the fast charging process, the output voltage will overshoot due to the power transient response characteristics of the fast charging mobile power supply. If the overshoot voltage is too large, it will have a certain impact on the safety of the fast charging mobile power supply, and even damage the fast charging mobile power supply in serious cases.

SUMMARY OF THE INVENTION

The present application provides a fast-charging protection circuit and method, a fast-charging chip, and a fast-charging power supply device, which can quickly detect the pulling-out action of the external device in advance in response to the sudden pulling-out of the external device during the fast-charging process. And the output voltage is reduced in advance before the external device is completely unplugged, so that the overshoot of the output voltage can be effectively reduced, and the safety of fast-charging power supply devices, such as fast-charging mobile power supplies or fast-charging adapters, can be improved.

A first aspect of the present application provides a fast charging protection circuit, the fast charging protection circuit includes a USB interface, a voltage conversion module, a fast charging control module, and a plug-in detection module. The USB interface is used for electrical connection with external devices. The voltage conversion module is electrically connected to the USB interface. The fast charge control module is electrically connected to the voltage conversion module and the USB interface, respectively, and the fast charge control module is used to obtain the fast charge protocol signal of the external device through the USB interface, and according to the fast charge The charging protocol signal identifies a fast charging voltage request of the external device, and controls the voltage conversion module to output a corresponding fast charging voltage to the USB interface according to the fast charging voltage request, so as to rapidly charge the external device. The plug-in detection module is electrically connected with the USB interface, and is used for real-time detection of the fast-charging protocol signal through the USB interface, and outputting a pulling-out signal when it is detected that the fast-charging protocol signal disappears. Wherein, the fast charging protocol signal disappears when the external device starts to be pulled out. The fast charging control module is also electrically connected to the output end of the plugging detection module, and the fast charging control module is further configured to control the voltage conversion module to change the output voltage from the output voltage to the output terminal when receiving the pullout signal. The fast charging voltage is reduced to a preset voltage. Wherein, the time required from when the plugging detection module detects that the fast charging protocol signal disappears to when the voltage conversion module starts to reduce the output voltage is less than the time from when the external device is initially pulled out to when it is completely pulled out. time needed.

A second aspect of the present application provides a fast charging chip, which is used in a fast charging power supply device. The fast-charging power supply device includes a USB interface that is electrically connected to an external device. The fast charging chip includes a voltage conversion module, a fast charging control module, and a plug-in detection module. The voltage conversion module is electrically connected to the USB interface. The fast charge control module is electrically connected to the voltage conversion module and the USB interface, respectively, and the fast charge control module is used to obtain the fast charge protocol signal of the external device through the USB interface, and according to the fast charge The charging protocol signal identifies a fast charging voltage request of the external device, and controls the voltage conversion module to output a corresponding fast charging voltage to the USB interface according to the fast charging voltage request, so as to rapidly charge the external device. The plug-in detection module is electrically connected with the USB interface, and is used for real-time detection of the fast-charging protocol signal through the USB interface, and outputting a pulling-out signal when it is detected that the fast-charging protocol signal disappears. Wherein, the fast charging protocol signal disappears when the external device starts to be pulled out. The fast charging control module is also electrically connected to the output end of the plugging detection module, and the fast charging control module is further configured to control the voltage conversion module to change the output voltage from the output voltage to the output terminal when receiving the pullout signal. The fast charging voltage is reduced to a preset voltage. Wherein, the time required from when the plugging detection module detects that the fast charging protocol signal disappears to when the voltage conversion module starts to reduce the output voltage is less than the time from when the external device is initially pulled out to when it is completely pulled out. time needed.

A third aspect of the present application provides a fast charging protection circuit, where the fast charging protection circuit includes a USB interface electrically connected to an external device, and the fast charging chip described in the second aspect above. Wherein, the voltage conversion module, the fast charging control module and the plug-in detection module of the fast charging chip are all electrically connected to the USB interface.

A fourth aspect of the present application provides a fast charging power supply device, wherein the fast charging power supply device includes the fast charging protection circuit described in the first aspect or the third aspect and a power input interface. Wherein, the fast charging protection circuit is used for charging external devices. The power input interface is electrically connected to the fast charging protection circuit, and the power input interface is used for receiving an external power supply to provide an input voltage to the fast charging protection circuit.

A fifth aspect of the present application provides a fast charging protection method, where the fast charging protection method is applied to the fast charging protection circuit described in the first aspect or the third aspect, or the fast charging protection circuit described in the second aspect. In the charging chip, or in the fast charging power supply device described in the fourth aspect. The fast charging protection method includes: during the fast charging process, real-time detection of the fast charging protocol signal by the plugging detection module; when the plugging detection module detects that the fast charging protocol signal disappears, the plugging detection module detects The module outputs a pull-out signal, wherein the fast-charging protocol signal disappears when the external device starts to be pulled out; and the voltage conversion module is controlled to reduce the output voltage from the fast-charging voltage to a preset voltage according to the pull-out signal. Wherein, the time required from when the plugging detection module detects that the fast charging protocol signal disappears to when the voltage conversion module starts to reduce the output voltage is less than the time from when the external device is initially pulled out to when it is completely pulled out. time needed.

The fast charging protection circuit and method proposed in the present application can detect the fast charging protocol signal in real time through the plug-in detection module during the fast charging process, the response speed is fast, the pull-out action of the external device can be quickly detected in advance, and the external device can be detected in the external device. The output voltage of the voltage conversion module is reduced in advance before being completely unplugged, so that the overshoot of the output voltage can be effectively reduced, thereby improving the reliability of fast-charging power supply devices, such as fast-charging mobile power supplies or fast-charging adapters.

Description of drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings that are used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present application, and for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

FIG. 1 is a schematic structural diagram of a fast charging circuit provided in the prior art.

FIG. 2 is a schematic diagram illustrating a voltage overshoot of the output voltage of the fast charging circuit shown in FIG. 1 when an external device is pulled out.

FIG. 3 is a schematic diagram of functional modules of a fast charging protection circuit according to the first embodiment of the present application.

FIG. 4 is a schematic diagram of a circuit structure of the fast charging protection circuit shown in FIG. 3 .

Figure 5 is a schematic diagram of the pin structure of two USB interfaces, wherein the structure (A) in Figure 5 is the pin structure of the USB TYPE-A interface; the structure (B) in Figure 5 is the lead structure of the USB TYPE-C interface. The structure of the foot.

FIG. 6 is a schematic diagram of another circuit structure of the fast charging protection circuit shown in FIG. 3 .

7 is a schematic diagram illustrating a voltage overshoot of the output voltage of the fast charging protection circuit shown in FIG. 3 , FIG. 4 or FIG. 6 when the external device is pulled out.

FIG. 8 is a schematic diagram of functional modules of a fast charging protection circuit according to a second embodiment of the present application.

FIG. 9 is a schematic diagram of functional modules of a fast charging power supply device according to an embodiment of the present application.

FIG. 10 is a schematic diagram of functional modules of a fast-charging mobile power supply according to an embodiment of the present application.

FIG. 11 is a schematic diagram of functional modules of a fast charging adapter provided by an embodiment of the present application.

FIG. 12 is a flowchart of a fast charging protection method provided by an embodiment of the present application.

Description of main component symbols

The following specific embodiments will further illustrate the present application in conjunction with the above drawings.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Wherein, the accompanying drawings are only used for exemplary description, and are only schematic diagrams, which should not be construed as limitations on the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art. The terms used in the specification of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application.

The following is a brief introduction to the fast charging circuit in the existing fast charging power supply equipment (not shown).

As shown in FIG. 1 , the existing fast charging circuit 100 generally includes a voltage conversion module 11 , a fast charging control module 12 , and a USB interface 13 . The USB interface 13 is used for electrical connection with an external device 200 , such as a mobile phone, through the USB charging cable 21 . The voltage conversion module 11 is electrically connected to the VBUS pin of the USB interface 13 , and outputs a charging voltage to the external device 200 through the VBUS pin of the USB interface 13 . Under normal circumstances, for example, when the external device 200 is not inserted into the USB interface 13 , the voltage conversion module 11 outputs a preset normal charging voltage Vout, such as a normal charging voltage of 5V, to the VBUS pin of the USB interface 13 . . Wherein, the voltage conversion module 11 may be a DC-DC BOOST boosting module. It can be understood that the fast charging control module 12, or the voltage conversion module 11 and the fast charging control module 12 may be provided in the fast charging chip.

The fast charging control module 12 is electrically connected to the voltage conversion module 11 and the USB interface 13 respectively. When the external device 200 is inserted into the USB interface 13, the voltage conversion module 11 outputs a preset normal charging voltage Vout to charge the external device 200, and at this time, the external device 200 enters the normal charging mode. After the external device 200 is inserted into the USB interface 13 , the fast charging control module 12 can communicate with the external device 200 through the USB interface 13 to obtain the fast charging protocol signal of the external device 200 .

The fast charging control module 12 is further configured to identify the fast charging voltage request of the external device 200 according to the fast charging protocol signal, and control the voltage conversion module 11 to the USB interface 13 according to the fast charging voltage request. The VBUS pin outputs the corresponding fast charging voltage, so as to quickly charge the external device 200, and at this time, the external device 200 enters the fast charging mode.

For example, the external device 200 applies for a fast charging voltage of 12V, and the fast charging control module 12 controls the voltage conversion module 11 to output a voltage Vout of 12V to the VBUS pin of the USB interface 13, so as to provide the external device with a voltage Vout of 12V. 200 for fast charging. Wherein, the fast charging control module 12 can obtain the fast charging protocol signal through the DP pin and the DM pin of the USB interface 13 .

When the USB charging cable 21 is suddenly pulled out from the USB interface 13, or the USB charging cable 21 is suddenly pulled out from the external device 200, the fast charging protocol signal disappears. When the fast charging control module 12 recognizes that the fast charging protocol signal disappears, the fast charging control module 12 controls the voltage conversion module 11 to reduce the output voltage Vout to a preset voltage, such as 5V.

Since each connection pin of the USB interface 13 and the USB input interface of the USB charging cable 21 has a certain length in mechanical structure, it takes a certain time to separate the two. As shown in FIG. 2 , the process of unplugging the external device 200 during the fast charging process is as follows: starting to unplug the external device 200 at time t1, and completely unplugging the external device 200 at time t2. That is, the time ΔT1 required from when the external device 200 is pulled out to when it is completely pulled out is about 10 to 20 ms. When the external device 200 is pulled out until the fast charging control module 12 recognizes that the fast charging protocol signal disappears, the response time required by the fast charging control module 12 is also about 10-20 ms. That is to say, the response time for the fast charging control module 12 to recognize the disappearance of the fast charging protocol signal is approximately equal to the time required for the external device 200 to be completely pulled out. In this way, when the fast charging control module 12 controls the voltage conversion module 11 to reduce the output voltage Vout to a preset voltage, the external device 200 has been completely pulled out.

As shown in FIG. 2 , within the time ΔT1, for example, within 10 ms, the fast charging control module 12 has not recognized the disappearance of the fast charging protocol signal, and the output voltage Vout of the voltage conversion module 11 is maintained at the setting of 12V. Value. The external device 200 is completely pulled out at time t2, due to the sudden change of the output load current of the voltage conversion module 11 (the external device 200 is suddenly pulled out, which is equivalent to the sudden change of the output load current to 0), and the fast charging The power transient response characteristics of the power supply equipment will cause the output voltage Vout of the voltage conversion module 11 to overshoot. In severe cases, the overshoot voltage will overshoot to about 15.5V, and the overshoot amplitude ΔV1=3.5V , which seriously affects the safety of fast charging power supply equipment.

The current general approach to solve this problem is to reduce the magnitude of the overshoot voltage by improving the transient response of the voltage conversion module 11 , for example, by increasing the capacity of the filter capacitor Cout, or by changing the analog circuit of the voltage conversion module 11 itself parameters (such as increasing the DC-DC switching frequency, or changing control loop parameters, etc.). However, in the existing methods for improving the overshoot voltage, the cost of the fast charging power supply equipment will be increased by increasing the capacity of the filter capacitor Cout, and the method of modifying the analog circuit parameters of the voltage conversion module 11 itself is complicated and not easy to implement. .

In view of the above problems existing in the prior art, the embodiments of the present application provide a fast charging protection circuit and method, and a fast charging mobile power supply and a fast charging adapter having the fast charging protection circuit, which can prevent the occurrence of problems in the fast charging process. If the external device is suddenly pulled out, it can quickly detect the pull-out action of the external device in advance, and reduce the output voltage in advance before the external device is completely pulled out, so as to effectively reduce the overshoot of the output voltage and improve the speed. The safety of charging power bank / fast charging adapter.

FIG. 3 is a schematic diagram of functional modules of a fast charging protection circuit according to the first embodiment of the present application. As shown in FIG. 3 , the fast charging protection circuit 300 includes a voltage conversion module 31 , a fast charging control module 32 , a USB interface 33 , and a plug-in detection module 34 . For the specific technical details of the voltage conversion module 31 , the fast charging control module 32 and the USB interface 33 , please refer to the relevant specific descriptions of the voltage conversion module 11 , the fast charging control module 12 and the USB interface 13 in FIG. 1 above. , in order to save space and avoid repetition, no repetition is repeated here. It can be understood that some or all of the structures of the voltage conversion module 31 , the fast charging control module 32 , and the plugging detection module 34 may be provided in the fast charging chip.

In this embodiment, the plug-in detection module 34 is electrically connected to the USB interface 33 for real-time detection of the fast charging protocol signal through the USB interface 33, and when it is detected that the fast charging protocol signal disappears When the pull-out signal is output. The fast charging control module 32 is also electrically connected to the output end of the plug-in detection module 34, and the fast-charge control module 32 is further configured to control the voltage conversion module 31 to convert the voltage conversion module 31 to The output voltage is reduced from the fast charging voltage to a preset voltage, eg, a normal charging voltage of 5V.

Wherein, the fast charging protocol signal disappears when the external device 200 starts to be pulled out. The fast charging protocol signals include but are not limited to the DP/DM signals of the fast charging protocol, and/or the CC1/CC2 signals of the Type-C protocol.

In this embodiment, the plug-in detection module 34 is electrically connected to a preset pin of the USB interface 33 for acquiring the fast charging protocol signal, and the plug-in detection module 34 is used for real-time detection of the The voltage of the preset pin changes, and it is determined whether the voltage change of the preset pin satisfies the preset condition, and when the voltage change of the preset pin satisfies the preset condition, it is determined that the external device 200 starts to be used. Unplug and the fast charge protocol signal disappears, and output the unplug signal.

In this embodiment, the USB interface 33 includes a USB TYPE-A interface and a USB TYPE-C interface, and the preset pins are the DP pins of the USB TYPE-A interface or the USB TYPE-C interface the CC1/CC2 pins.

The plug-in detection module 34 includes a comparison module 341, the input end of the comparison module 341 is electrically connected with the preset pins of the USB interface 33, and the comparison module 341 is used to compare the preset pins of the USB interface 33. The voltage of the pin is compared with a preset reference voltage to determine whether the voltage change of the preset pin of the USB interface 33 satisfies the preset condition.

In this embodiment, the plug detection module 34 further includes a debounce (Debounce) module 342 , and the debounce module 342 is electrically connected between the output end of the comparison module 341 and the fast charge control module 32 , the de-jitter module 342 is configured to transmit the pull-out signal to the fast charge control module 32 when the pull-out signal is continuously received within a preset time period. Wherein, the preset duration is less than the time required for the external device to be pulled out from the beginning to being pulled out completely. The preset time can be set to 1 ms, for example. It can be understood that, by setting the debounce module 342 to set a debounce time of 1 ms, misoperations caused by disturbances such as glitches can be prevented.

In this embodiment, the time required from the plugging detection module 34 detecting that the fast charging protocol signal disappears to the voltage conversion module 31 starting to reduce the output voltage Vout is less than the time the external device 200 is The time it takes to be pulled out completely. In this way, when the voltage conversion module 31 starts to reduce the output voltage, the electrical connection between the USB interface 33 and the external device 200 has not been completely disconnected, and the voltage conversion module 31 passes the USB interface 33 Continue to output the charging voltage for the external device 200 . That is, the fast charging control module 32 controls the voltage conversion module 31 to reduce the output voltage before the external device 200 is completely pulled out.

The fast charging protection circuit 300 proposed in the present application detects the fast charging protocol signal in real time through the plug-in detection module 34 during the fast charging process, has a fast response speed, and can quickly detect the pull-out action of the external device 200 in advance, and detect the external device 200 in the external Before the device 200 is completely pulled out, that is, before the external device 200 is completely disconnected from the fast charging mobile power supply or the fast charging adapter, the output voltage of the voltage conversion module 31 is reduced in advance, so that the overshoot of the output voltage can be effectively reduced range, thereby improving the reliability of the fast-charging power bank or fast-charging adapter.

FIG. 4 is a schematic diagram of a circuit structure of the fast charging protection circuit shown in FIG. 3 . As shown in FIG. 4 , the fast charging protection circuit 400 includes a voltage conversion module 41 , a fast charging control module 42 , a USB interface 43 , and a plug-in detection module 44 . The voltage conversion module 41 , the fast charging control module 42 , the USB interface 43 , and the plug-in detection module 44 are the same as the voltage conversion module 31 , the fast-charge control module 32 , the USB interface 33 , and the plug-in detection module shown in FIG. 3 . The modules 34 are in one-to-one correspondence.

In this embodiment, the USB interface 43 is a USB TYPE-A interface, including a VBUS pin, a DM pin, a DP pin, and a GND pin. The preset pin is the DP pin of the USB interface.

The comparison module includes a comparator 441, and the comparator 441 includes two input terminals, one of which is electrically connected to the DP pin of the USB interface 43, and the other input terminal is used to receive the first reference voltage, so the The output end of the comparator 441 is electrically connected to the fast charging control module 42 through the debounce module 442 .

Figure 5 shows the structure of the pins of the two USB interfaces. Among them, the structure (A) in FIG. 5 is the pin structure of the USB TYPE-A interface, and the structure (B) in FIG. 5 is the structure of the pins of the USB TYPE-C interface. Due to the special structure of the USB interface, its VBUS pin and GND pin are longer in mechanical structure than the DP/DM pins and CC1/CC2 pins.

For the USB interface 33, when the USB charging cable 21 is pulled out, the DP/DM/CC1/CC2 pins of the two will be disconnected first. At this time, the fast charging protocol signal disappears, and then the VBUS/GND pin will be disconnected. The foot is disconnected, and this time interval is generally about 10-20ms. That is to say, the moment when the DP/DM/CC1/CC2 pins are disconnected corresponds to the moment when the external device 200 starts to be pulled out, and the moment when the VBUS/GND pin is disconnected corresponds to the moment when the external device 200 is completely disconnected. The moment to pull out.

For the USB TYPE-A interface, when an external device 200 is inserted, according to the characteristics of the fast charging protocol, when the fast charging connection is successful, the voltage on the DP pin is generally above 0.325V. When the external device 200 is pulled out , that is, after the fast charging connection is disconnected, the voltage on the DP pin will be pulled down to less than 0.325V.

In this embodiment, the comparator 441 is configured to output the pull-out signal when the voltage of the DP pin is lower than the first reference voltage, that is, the preset condition is the DP pin voltage is lower than the first reference voltage. Wherein, the first reference voltage may be set to 0.325V. In this way, when it is detected that the voltage of the DP pin is less than 0.325V and lasts for more than 1ms (to prevent interference such as glitches, a debounce time of 1ms is set), it can be determined that the external device 200 is pulled out.

In one embodiment, as shown in FIG. 4 , the positive input terminal of the comparator 441 is electrically connected to the DP pin of the USB interface 43 , and the negative input terminal receives the first reference voltage of 0.325V. According to the working principle of the comparator, when the external device 200 is in the fast charging state, the voltage of the DP pin is higher than 0.325V, and the comparator outputs a high level; when the external device 200 is pulled out, the voltage of the DP pin is higher than 0.325V. When the voltage is lower than 0.325V, the comparator 441 outputs a low level. That is, in the one embodiment, the pull-out signal is a low-level signal.

Optionally, in another implementation manner, the negative input terminal of the comparator 441 is electrically connected to the DP pin of the USB interface 43, and the positive input terminal receives the first reference voltage of 0.325V. It can be understood that, in the another implementation manner, the pull-out signal is a high-level signal.

FIG. 6 is a schematic diagram of another circuit structure of the fast charging protection circuit shown in FIG. 3 . As shown in FIG. 6 , the fast charging protection circuit 500 includes a voltage conversion module 51 , a fast charging control module 52 , a USB interface 53 , and a plug-in detection module 54 . The voltage conversion module 51 , the fast charging control module 52 , the USB interface 53 , and the plug-in detection module 54 are the same as the voltage conversion module 31 , the fast-charge control module 32 , the USB interface 33 , and the plug-in detection module shown in FIG. 3 . The modules 34 are in one-to-one correspondence.

In this embodiment, the USB interface 53 is a USB TYPE-C interface, including a VBUS pin, a DM pin, a DP pin, a CC1 pin, a CC2 pin, and a GND pin. The preset pins are the CC1 pin and the CC2 pin of the USB interface.

The comparison module includes a first comparator 5411 and a second comparator 5412, wherein the first comparator 5411 includes two input terminals, one of which is electrically connected to the CC1 pin of the USB interface 53, and the other is electrically connected to the CC1 pin of the USB interface 53. An input terminal is used to receive the second reference voltage. The second comparator 5412 includes two input terminals, one of which is electrically connected to the CC2 pin of the USB interface 53, and the other input terminal is used for receiving a third reference voltage.

For the USB TYPE-C interface, when an external device 200 is inserted, according to the characteristics of the fast charging protocol, when the fast charging connection is successful, the voltage on the CC1 pin or the CC2 pin is generally lower than 2V. When the external device 200 is pulled out, that is, after the fast charging connection is disconnected, the voltage on the CC1 pin or the CC2 pin will be pulled up to 3.3V.

In this embodiment, the first comparator 5411 is configured to output the pull-out signal when the voltage of the CC1 pin is higher than the second reference voltage. The second comparator 5412 is configured to output the pull-out signal when the voltage of the CC2 pin is higher than the third reference voltage.

Wherein, the second reference voltage and the third reference voltage may both be set to 2.9V. Therefore, by detecting and judging whether the voltage of the CC1 pin or the CC2 pin is higher than 2.9V, it can be judged whether the external device 200 is pulled out.

The plug detection module 54 further includes a logic gate circuit 543, the logic gate circuit 543 includes two input terminals, one of which is electrically connected to the output terminal of the first comparator 5411, and the other input terminal is electrically connected to the output terminal of the first comparator 5411. The output end of the second comparator 5412 is electrically connected, and the output end of the logic gate circuit 543 is electrically connected to the fast charging control module 52, and the logic gate circuit 543 is used for the first comparator 5411, the second The signals output by the two comparators 5412 are subjected to logical operations, so as to output the voltage when the voltage of the CC1 pin is higher than the second reference voltage, or the voltage of the CC2 pin is higher than the third reference voltage Unplug the signal. That is, the preset condition is that the voltage of the CC1 pin is higher than the second reference voltage, or the voltage of the CC2 pin is higher than the third reference voltage.

In an embodiment, as shown in FIG. 6 , the positive input terminal of the first comparator 5411 is electrically connected to the CC1 pin of the USB interface 53 , and the negative input terminal receives the second reference voltage of 2.9V. The positive input terminal of the second comparator 5412 is electrically connected to the CC2 pin of the USB interface 53, and the negative input terminal receives a third reference voltage of 2.9V. According to the working principle of the comparator, when the external device 200 is in the fast charging state, and the voltage of the CC1 pin or the CC2 pin is lower than 2.9V, the first comparator 5411 and the second comparator 5412 both output low voltage level; when the external device 200 is pulled out, the voltage of the CC1 pin or the CC2 pin is higher than 2.9V, and both the first comparator 5411 and the second comparator 5412 output a high level. That is, in the one embodiment, the pull-out signal is a high-level signal.

In one implementation manner, the logic gate circuit 543 is an OR gate, and the OR gate is used to perform a logical OR operation on the signals output by the first comparator 5411 and the second comparator 5412, so as to perform a logical OR operation in all When the voltage of the CC1 pin is higher than the second reference voltage, or the voltage of the CC2 pin is higher than the third reference voltage, the high-level signal, that is, the pull-out signal, is output.

In another embodiment, the negative input terminal of the first comparator 5411 is electrically connected to the CC1 pin of the USB interface 53, and the positive input terminal receives the second reference voltage of 2.9V. The negative input terminal of the second comparator 5412 is electrically connected to the CC2 pin of the USB interface 53, and the positive input terminal receives a third reference voltage of 2.9V. It can be understood that, in the another implementation manner, the pull-out signal is a low-level signal.

In the other embodiment, the logic gate circuit 543 is an AND gate, and the AND gate is used to perform a logical AND operation on the signals output by the first comparator 5411 and the second comparator 5412, so as to be in the When the voltage of the CC1 pin is higher than the second reference voltage, or the voltage of the CC2 pin is higher than the third reference voltage, the low-level signal, that is, the pull-out signal, is output.

As shown in FIG. 6 , the plugging detection module 54 includes two debounce modules 5421 and 5422, one of the debounce modules 5421 is electrically connected to the output end of the first comparator 5411 and the logic gate circuit Between one input terminal of the second comparator 5412 and the other input terminal of the logic gate circuit 543, the other debounce module 5422 is electrically connected.

In another implementation manner, the plugging detection module 54 may include a debounce module, and the debounce module is electrically connected between the output end of the logic gate circuit 543 and the fast charge control module 52 .

7 is a schematic diagram illustrating a voltage overshoot of the output voltage Vout of the fast charging protection circuit shown in FIG. 3 , FIG. 4 or FIG. 6 when the external device 200 is pulled out.

As mentioned earlier, the VBUS and GND pins of the USB interface are mechanically longer than the DP/DM pins and CC1/CC2 pins. In this way, as shown in FIG. 7 , the process of unplugging the external device 200 during the fast charging process is: starting to unplug the external device 200 at time t1, at this time, the DP/DM/CC1 of the USB interface 33 The /CC2 pin is disconnected from the DP/DM/CC1/CC2 pin of the USB charging cable 21 of the external device 200, and the fast charging protocol signal disappears; when the external device 200 is completely pulled out at time t2, this , the VBUS/GND pin of the USB interface 33 is disconnected from the VBUS/GND pin of the USB charging cable 21 .

During the process of pulling out the external device 200, when the DP/DM/CC1/CC2 pins of the USB interface 33 are disconnected from the DP/DM/CC1/CC2 pins of the USB charging cable 21, the The fast charging protocol signal disappears. After a delay of ΔT2, such as a debounce time of 1 ms, that is, at time t3, the fast charging control module 32 controls the voltage conversion module 31 to reduce the output voltage Vout. At this time, since ΔT2<ΔT1, the USB interface 33 The VBUS/GND pin of the USB charging cable 21 is not disconnected from the VBUS/GND pin of the USB charging cable 21, and the external device 200 continues to draw current from the VBUS pin. Therefore, the output voltage Vout of the voltage conversion module 31 There will be no overshoot. Please refer to FIG. 3 again, the output terminal of the voltage conversion module 31 is connected to the ground through the filter capacitor Cout. It can be understood that although the fast charge control module 32 controls the voltage conversion module 31 to reduce the output voltage Vout from 12V To 5V, but due to the existence of the filter capacitor Cout, the output voltage Vout will not undergo a sudden change in voltage, that is, it will not change from the fast charge voltage of 12V to the normal voltage of 5V, but will decrease linearly from the fast charge voltage of 12V.

When the external device 200 or the USB charging cable 21 is completely pulled out, the output load current of the voltage conversion module 31 suddenly changes to 0, and the output voltage Vout starts to rush up due to the transient response. The output voltage Vout has been continuously reduced for a period of time ΔT3=ΔT1-ΔT2, the voltage value of the output voltage Vout has been reduced a lot, and the overshoot voltage that appears will no longer overshoot the original overshoot voltage value at the 12V or 9V output voltage .

Taking the fast charging voltage of 12V as an example, in a fast charging power supply device (such as a fast charging mobile power supply or a fast charging adapter) that does not use the fast charging protection circuit of the present application, as shown in Figure 2, the overshoot voltage can reach 15.5V, the overshoot amplitude ΔV1 is 3.5V. In contrast, in the fast charging structure using the fast charging protection circuit of the present application, as shown in FIG. 7 , the overshoot voltage is 13.2V, the overshoot amplitude ΔV2 is 1.2V, and the overshoot amplitude is greatly reduced .

It can be seen that, compared with the existing fast charging circuit, the fast charging protection circuit proposed in the present application detects the DP signal on the USB interface in real time during the fast charging process, or the voltage characteristics of the CC1 and CC2 signals to determine in advance whether the external device is unplugged. Take action and reduce the output voltage of the boost boost circuit to 5V in advance before the external device is completely disconnected from the fast charging mobile power supply/fast charging adapter. In this way, the output voltage of the boost boost circuit will be lower than the initial speed. The charging voltage can effectively reduce the overshoot of the output voltage Vout even if the boost transient response is not improved, thereby improving the reliability of the fast charging mobile power supply/fast charging adapter.

In addition, the fast charging protection circuit proposed in this application detects the fast charging protocol signal by plugging and unplugging the detection module, and the response speed is fast, and it does not need to be improved by increasing the capacity of the filter capacitor at the output end or changing the analog circuit parameters of the boost booster circuit itself. By boosting the transient response, the purpose of effectively reducing the overshoot amplitude of the output voltage Vout can be achieved, thereby realizing a significant reduction in the overshoot voltage amplitude in a low-cost method.

FIG. 8 is a schematic diagram of functional modules of a fast charging protection circuit according to a second embodiment of the present application. The fast charging protection circuit 600 includes a USB interface 61 and a fast charging chip 62 . As shown in FIG. 8 , in this embodiment, the fast charging chip 62 includes a voltage conversion module 621 , a fast charging control module 622 , and a plug-in detection module 623 . Wherein, the voltage conversion module 621 , the fast charging control module 622 , and the plug-in detection module 623 are all electrically connected to the USB interface 61 . The USB interface 61 , the voltage conversion module 621 , the fast charging control module 622 , and the plugging detection module 623 are the same as the USB interface 33 , the voltage conversion module 31 , the fast charging control module 32 , and the plugging detection module 34 shown in FIG. 3 . One-to-one correspondence. For the specific technical details of the USB interface 61 , the voltage conversion module 621 , the fast charging control module 622 , and the plug-in detection module 623 , please refer to the USB interface 33 , the voltage conversion module 31 , and the fast charging control module 32 in FIG. 3 . , and the relevant specific descriptions of the plugging detection module 34 , for the sake of saving space and avoiding repetition, repeated descriptions are not repeated here.

FIG. 9 is a schematic diagram of functional modules of a fast charging power supply device according to an embodiment of the present application. As shown in FIG. 9 , the fast charging power supply device 700 includes a power input interface 71 and a fast charging protection circuit 72 . The power input interface 71 is electrically connected to the fast charging protection circuit 72 , and the power input interface 71 is used to receive an external power supply, such as 220V AC mains, to provide an input voltage to the fast charging protection circuit 72 . . The fast charging protection circuit 72 is used for charging the external device 200 .

The fast charging protection circuit 72 may correspond to the fast charging protection circuits 300 , 400 , 500 and 600 shown in FIG. 3 , FIG. 4 , FIG. 6 or FIG. 8 , and the specific technical details of the fast charging protection circuit 72 Please refer to the relevant detailed descriptions of the fast charging protection circuits 300 , 400 , 500 , and 600 shown in FIG. 3 , FIG. 4 , FIG. 6 or FIG. 8 . In order to save space and avoid repetition, repeated descriptions are not repeated here.

The fast-charging power supply device 700 may be the fast-charging mobile power supply 800 shown in FIG. 10 or the fast-charging adapter 900 shown in FIG. 11 .

FIG. 10 is a schematic diagram of functional modules of a fast-charging mobile power supply according to an embodiment of the present application. As shown in FIG. 10 , the fast charging mobile power supply 800 includes a power input interface 81 , a battery 82 and a fast charging protection circuit 83 . The fast charging protection circuit 83 may correspond to the fast charging protection circuits 300 , 400 , 500 and 600 shown in FIG. 3 , FIG. 4 , FIG. 6 or FIG. 8 . For the specific technical details of the fast charging protection circuit 83 , please refer to the related specific descriptions of the fast charging protection circuits 300 , 400 , 500 , and 600 . In order to save space and avoid repetition, repeated descriptions are not repeated here.

Wherein, the power input interface 81 is used for receiving an external power source, such as 220V AC mains power. The battery 82 is electrically connected to the power input interface 81 and the fast charging protection circuit 83 respectively, and the battery 82 is used for receiving the input voltage of the external power source for charging. The voltage conversion module of the fast charging protection circuit 83 is used to convert the voltage of the battery 82 into a preset voltage or a fast charging voltage corresponding to the fast charging protocol signal, so as to charge external devices.

The fast-charging mobile power supply proposed in the present application, by using the fast-charging protection circuit 83, can achieve a significant reduction in the amplitude of the overshoot voltage with a simple circuit design at low cost, and has high reliability.

FIG. 11 is a schematic diagram of functional modules of a fast charging adapter provided by an embodiment of the present application. As shown in FIG. 11 , the fast charging adapter 900 includes a power input interface 91 , an AC-DC conversion module 92 , and a fast charging protection circuit 93 . The fast charging protection circuit 93 may correspond to the fast charging protection circuits 300 , 400 , 500 and 600 shown in FIG. 3 , FIG. 4 , FIG. 6 or FIG. 8 . For the specific technical details of the fast charging protection circuit 93 , please refer to the relevant specific descriptions of the fast charging protection circuits 300 , 400 , 500 , and 600 . In order to save space and avoid repetition, repeated descriptions are not repeated here.

Wherein, the power input interface 91 is used for receiving an external power supply, such as 220V AC mains power. The AC-DC conversion module 92 is electrically connected to the power input interface 91 and the fast charging protection circuit 93 respectively, and the AC-DC conversion module 92 is used to convert the input voltage of the external power source into a DC voltage. The voltage conversion module of the fast charging protection circuit 93 can be used to convert the DC voltage into a preset voltage or a fast charging voltage corresponding to the fast charging protocol signal, so as to charge an external device.

The fast charging adapter proposed in the present application, by using the fast charging protection circuit 93, can achieve a significant reduction in the amplitude of the overshoot voltage with a simple circuit design at low cost, and has high reliability.

FIG. 12 is a flowchart of a fast charging protection method provided by an embodiment of the present application. The fast charging protection method can be applied to the fast charging protection circuits 300 , 400 , 500 and 600 shown in FIG. 3 , FIG. 4 , FIG. 6 or FIG. 8 .

In this embodiment, as shown in FIG. 12 , the fast charging protection method includes the following steps.

Step 1001: During the fast charging process, the fast charging protocol signal is detected in real time by the plugging and unplugging detection module.

In this embodiment, the step 1001 may specifically include:

During the fast charging process, the voltage change of the preset pins of the USB interface for obtaining the fast charging protocol signal is detected in real time by the plugging detection module;

Determine whether the voltage change of the preset pin satisfies the preset condition; and

When it is detected that the voltage change of the preset pin satisfies the preset condition, it is determined that the external device starts to be pulled out, and the fast charging protocol signal disappears.

In this embodiment, the USB interface includes a USB TYPE-A interface and a USB TYPE-C interface, and the preset pin is the DP pin of the USB TYPE-A interface or the DP pin of the USB TYPE-C interface. CC1/CC2 pins.

The step of judging whether the voltage change of the preset pin satisfies the preset condition may specifically include: comparing the voltage of the preset pin of the USB interface with a preset reference voltage to determine the preset voltage of the USB interface. Set whether the voltage change of the pin satisfies the preset condition.

Step 1002, when the plugging detection module detects that the fast charging protocol signal disappears, outputting a plugging signal through the plugging detection module.

Step 1003: Control the voltage conversion module to reduce the output voltage from the fast charging voltage to a preset voltage according to the pull-out signal.

Wherein, the time required from when the plugging detection module detects that the fast charging protocol signal disappears to when the voltage conversion module starts to reduce the output voltage is less than the time from when the external device is initially pulled out to when it is completely pulled out. time needed.

For the specific technical details of steps 1001 to 1003 in this embodiment, reference may be made to the description of the related technical details of the embodiments shown in FIG. 3 to FIG. 8 , which will not be repeated here.

The fast charging protection method proposed in the present application detects the fast charging protocol signal in real time through the plug-in detection module during the fast charging process, so that the pull-out action of the external device can be quickly detected in advance, and the external device can be completely pulled out before the external device is completely pulled out. By reducing the output voltage of the voltage conversion module in advance, the overshoot of the output voltage can be effectively reduced, thereby improving the reliability of fast-charging power supply equipment, such as fast-charging mobile power supplies or fast-charging adapters.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application rather than limitations. Although the present application has been described in detail with reference to the above preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present application can be Any modification or equivalent replacement of the solution should not depart from the spirit and scope of the technical solution of the present application.

Claims (23)

1. A fast charging protection circuit, comprising: USB interface for electrical connection with external devices; a voltage conversion module, electrically connected to the USB interface; A fast charging control module, which is electrically connected to the voltage conversion module and the USB interface respectively, and the fast charging control module is used for acquiring the fast charging protocol signal of the external device through the USB interface, and according to the fast charging The protocol signal identifies a fast charging voltage request of the external device, and controls the voltage conversion module to output a corresponding fast charging voltage to the USB interface according to the fast charging voltage request, so as to quickly charge the external device; and The plug-in detection module is electrically connected to the USB interface, and is used for real-time detection of the fast-charging protocol signal through the USB interface, and when detecting that the fast-charging protocol signal disappears, outputting a pull-out signal, wherein the The fast charging protocol signal disappears when the external device starts to be pulled out; The fast charging control module is also electrically connected to the output end of the plugging detection module, and the fast charging control module is further configured to control the voltage conversion module to change the output voltage from the output voltage to the output terminal when receiving the pullout signal. the fast charging voltage is reduced to a preset voltage; Wherein, the time required from when the plugging detection module detects that the fast charging protocol signal disappears to when the voltage conversion module starts to reduce the output voltage is less than the time from when the external device is initially pulled out to when it is completely pulled out. time needed. 2 . The fast charging protection circuit according to claim 1 , wherein the plug detection module is electrically connected to a preset pin of the USB interface for obtaining the fast charging protocol signal, and the plug The pull detection module is used to detect the voltage change of the preset pin in real time, and judge whether the voltage change of the preset pin satisfies the preset condition, and when the voltage change of the preset pin satisfies the preset condition , determine that the external device starts to be pulled out and the fast charging protocol signal disappears, and output the pull-out signal. 3 . The fast charging protection circuit according to claim 2 , wherein the plug-in detection module comprises a comparison module, and an input end of the comparison module is electrically connected to a preset pin of the USB interface, and the The comparison module is configured to compare the voltage of the preset pin of the USB interface with a preset reference voltage to determine whether the voltage change of the preset pin of the USB interface satisfies the preset condition. 4 . The fast charging protection circuit according to claim 3 , wherein the plugging detection module further comprises a debounce module, and the debounce module is electrically connected to the output end of the comparison module and the fast charging module. 5 . Between control modules, the debounce module is configured to transmit the pull-out signal to the fast charge control module when the pull-out signal is continuously received within a preset time period, wherein the preset time period is less than The time required for the external device to be completely unplugged from when it was initially unplugged. 5. The fast charging protection circuit of claim 4, wherein the USB interface is a USB TYPE-A interface, including a VBUS pin, a DM pin, a DP pin, and a GND pin; the preset The pin is the DP pin of the USB interface; The comparison module includes a comparator, the comparator includes two input ends, one of the input ends of the comparator is electrically connected to the DP pin of the USB interface, and the other input end of the comparator is used for receiving a first reference voltage, and the output end of the comparator is electrically connected to the fast charging control module through the debounce module; Wherein, the comparator is configured to output the pull-out signal when the voltage of the DP pin is lower than the first reference voltage. 6. The fast charging protection circuit of claim 4, wherein the USB interface is a USB TYPE-C interface, comprising a VBUS pin, a DM pin, a DP pin, a CC1 pin, a CC2 pin, GND pin; the preset pin is the CC1 pin and the CC2 pin of the USB interface; The comparison module includes: The first comparator includes two input terminals, one of the input terminals of the first comparator is electrically connected to the CC1 pin of the USB interface, and the other input terminal of the first comparator is used to receive the second input terminal. a reference voltage, wherein the first comparator is configured to output the pull-out signal when the voltage of the CC1 pin is higher than the second reference voltage; and The second comparator includes two input terminals, one of the input terminals of the second comparator is electrically connected to the CC2 pin of the USB interface, and the other input terminal of the second comparator is used to receive the third a reference voltage, wherein the second comparator is configured to output the pull-out signal when the voltage of the CC2 pin is higher than the third reference voltage; The plug-in detection module further includes a logic gate circuit, the logic gate circuit includes two input ends, one of the input ends of the logic gate circuit is electrically connected with the output end of the first comparator, and the logic gate circuit is electrically connected to the output end of the first comparator. The other input end of the circuit is electrically connected to the output end of the second comparator, the output end of the logic gate circuit is electrically connected to the fast charging control module, and the logic gate circuit is used for comparing the first Logic operation is performed on the signals output by the comparator and the second comparator, so that when the voltage of the CC1 pin is higher than the second reference voltage, or the voltage of the CC2 pin is higher than the third reference voltage, output the unplug signal. 7 . The fast charging protection circuit according to claim 6 , wherein the plug detection module comprises two debounce modules, and one of the debounce modules is electrically connected to the first comparator. 8 . Between the output end and one of the input ends of the logic gate circuit, the other debounce module is electrically connected between the output end of the second comparator and the other input end of the logic gate circuit. 8 . The fast charging protection circuit according to claim 6 , wherein the debounce module is electrically connected between the output end of the logic gate circuit and the fast charging control module. 9 . 9. A fast-charging chip, applied in a fast-charging power supply device, the fast-charging power supply device comprising a USB interface electrically connected to an external device, wherein the fast-charging chip comprises: a voltage conversion module, electrically connected to the USB interface; A fast charging control module, which is electrically connected to the voltage conversion module and the USB interface respectively, and the fast charging control module is used for acquiring the fast charging protocol signal of the external device through the USB interface, and according to the fast charging The protocol signal identifies a fast charging voltage request of the external device, and controls the voltage conversion module to output a corresponding fast charging voltage to the USB interface according to the fast charging voltage request, so as to quickly charge the external device; and The plug-in detection module is electrically connected to the USB interface, and is used for real-time detection of the fast-charging protocol signal through the USB interface, and when detecting that the fast-charging protocol signal disappears, outputting a pull-out signal, wherein the The fast charging protocol signal disappears when the external device starts to be pulled out; The fast charging control module is also electrically connected to the output end of the plugging detection module, and the fast charging control module is further configured to control the voltage conversion module to change the output voltage from the output voltage to the output terminal when receiving the pullout signal. the fast charging voltage is reduced to a preset voltage; Wherein, the time required from when the plugging detection module detects that the fast charging protocol signal disappears to when the voltage conversion module starts to reduce the output voltage is less than the time from when the external device is initially pulled out to when it is completely pulled out. time needed. 10 . The fast charging chip according to claim 9 , wherein the plugging detection module is electrically connected to a preset pin of the USB interface for acquiring the fast charging protocol signal, and the plugging and unplugging The detection module is used to detect the voltage change of the preset pin in real time, and judge whether the voltage change of the preset pin satisfies the preset condition, and when the voltage change of the preset pin satisfies the preset condition, It is determined that the external device starts to be pulled out and the fast charging protocol signal disappears, and the pull-out signal is output. 11 . The fast charging chip according to claim 10 , wherein the plug-in detection module comprises a comparison module, an input end of the comparison module is electrically connected to a preset pin of the USB interface, and the comparison module is electrically connected to a preset pin of the USB interface. The module is configured to compare the voltage of the preset pin of the USB interface with a preset reference voltage to determine whether the voltage change of the preset pin of the USB interface satisfies the preset condition. 12 . The fast charging chip according to claim 11 , wherein the plugging detection module further comprises a debounce module, and the debounce module is electrically connected to the output end of the comparison module and the fast charging control module. 13 . Between modules, the debounce module is configured to transmit the pull-out signal to the fast charge control module when continuously receiving the pull-out signal within a preset time period, wherein the preset time period is less than the preset time period. The time required for the external device to be unplugged from the beginning to fully unplugged. 13. The fast charging chip according to claim 12, wherein the USB interface is a USB TYPE-A interface, including a VBUS pin, a DM pin, a DP pin, and a GND pin; The pin is the DP pin of the USB interface; The comparison module includes a comparator, the comparator includes two input ends, one of the input ends of the comparator is electrically connected to the DP pin of the USB interface, and the other input end of the comparator is used for receiving a first reference voltage, and the output end of the comparator is electrically connected to the fast charging control module through the debounce module; Wherein, the comparator is configured to output the pull-out signal when the voltage of the DP pin is lower than the first reference voltage. 14. The fast charging chip of claim 12, wherein the USB interface is a USB TYPE-C interface, including a VBUS pin, a DM pin, a DP pin, a CC1 pin, a CC2 pin, and a GND pin; the preset pin is the CC1 pin and the CC2 pin of the USB interface; The comparison module includes: The first comparator includes two input terminals, one of the input terminals of the first comparator is electrically connected to the CC1 pin of the USB interface, and the other input terminal of the first comparator is used to receive the second input terminal. a reference voltage, wherein the first comparator is configured to output the pull-out signal when the voltage of the CC1 pin is higher than the second reference voltage; and The second comparator includes two input terminals, one of the input terminals of the second comparator is electrically connected to the CC2 pin of the USB interface, and the other input terminal of the second comparator is used to receive the third a reference voltage, wherein the second comparator is configured to output the pull-out signal when the voltage of the CC2 pin is higher than the third reference voltage; The plug-in detection module further includes a logic gate circuit, the logic gate circuit includes two input ends, one of the input ends of the logic gate circuit is electrically connected with the output end of the first comparator, and the logic gate circuit is electrically connected to the output end of the first comparator. The other input end of the circuit is electrically connected to the output end of the second comparator, the output end of the logic gate circuit is electrically connected to the fast charging control module, and the logic gate circuit is used for comparing the first Logic operation is performed on the signals output by the comparator and the second comparator, so that when the voltage of the CC1 pin is higher than the second reference voltage, or the voltage of the CC2 pin is higher than the third reference voltage, output the unplug signal. 15 . The fast charging chip according to claim 14 , wherein the plug detection module comprises two debounce modules, and one of the debounce modules is electrically connected to the output of the first comparator. 16 . The other debounce module is electrically connected between the output end of the second comparator and the other input end of the logic gate circuit. 16 . The fast charging chip of claim 14 , wherein the debounce module is electrically connected between the output end of the logic gate circuit and the fast charging control module. 17 . 17. A fast charging protection circuit, comprising: USB interface for electrical connection with external devices; and The fast charging chip according to any one of claims 9-16, wherein a voltage conversion module, a fast charging control module and a plug-in detection module of the fast charging chip are all electrically connected to the USB interface. 18. A fast charging power supply device, comprising: The fast charging protection circuit according to any one of claims 1-8 or 17, the fast charging protection circuit is used for charging an external device; and A power input interface is electrically connected to the fast charging protection circuit, and the power input interface is used for receiving an external power supply to provide an input voltage to the fast charging protection circuit. 19. The fast-charging power supply device according to claim 18, wherein the fast-charging power supply device is a fast-charging mobile power supply, and the fast-charging mobile power supply further comprises an input interface with the power supply and the fast-charging protection a battery electrically connected to the circuit respectively, the battery is used for receiving the input voltage of the external power source to be charged; The voltage conversion module of the fast charging protection circuit is used to convert the voltage of the battery into a preset voltage or a fast charging voltage corresponding to the fast charging protocol signal, so as to charge the external device. 20 . The fast-charging power supply device according to claim 18 , wherein the fast-charging power supply device is a fast-charging adapter, and the fast-charging adapter further comprises a power input interface and the fast-charging protection circuit, respectively. an AC-DC conversion module electrically connected, the AC-DC conversion module is used to convert the input voltage of the external power supply into a DC voltage; The voltage conversion module of the fast charging protection circuit is used for converting the DC voltage into a preset voltage or a fast charging voltage corresponding to the fast charging protocol signal, so as to charge the external device. 21. A fast charging protection method, wherein the fast charging protection method is applied to the fast charging protection circuit according to any one of claims 1-8 or 17, and the fast charging protection method comprises: During the fast charging process, the fast charging protocol signal is detected in real time through the plug-in detection module; When the plugging detection module detects that the fast charging protocol signal disappears, the plugging detection module outputs a pulling signal, wherein the fast charging protocol signal disappears when the external device starts to be pulled out; as well as Controlling the voltage conversion module to reduce the output voltage from the fast charging voltage to a preset voltage according to the pull-out signal; Wherein, the time required from when the plugging detection module detects that the fast charging protocol signal disappears to when the voltage conversion module starts to reduce the output voltage is less than the time from when the external device is initially pulled out to when it is completely pulled out. time needed. 22. The fast charging protection method according to claim 21, wherein the real-time detection of the fast charging protocol signal by the plug-in detection module comprises: Detect the voltage change of the preset pin of the USB interface for obtaining the fast charging protocol signal in real time by the plugging detection module; Determine whether the voltage change of the preset pin satisfies the preset condition; and When it is detected that the voltage change of the preset pin satisfies the preset condition, it is determined that the external device starts to be pulled out and the fast charging protocol signal disappears. 23. The fast charging protection method according to claim 22, wherein the USB interface comprises a USB TYPE-A interface and a USB TYPE-C interface, and the preset pins are the ones of the USB TYPE-A interface. DP pin or CC1/CC2 pin of the USB TYPE-C interface; judging whether the voltage change of the preset pin satisfies the preset condition includes: The voltage of the preset pin of the USB interface is compared with a preset reference voltage to determine whether the voltage change of the preset pin of the USB interface satisfies the preset condition.

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