An output voltage follow feedback circuit and fast charger

Abstract

The embodiment of the application discloses an output voltage following feedback circuit and a fast charging charger, and belongs to the fast charging technical field, wherein the output voltage following feedback circuit comprises: a diode sampling subcircuit for collecting the voltage of the output end of a fast charging adapter, the output end of the diode sampling subcircuit is electrically connected with the input end of a voltage stabilizing diode feedback circuit, the output end of the voltage stabilizing diode feedback circuit is electrically connected with the control end of a switching tube subcircuit, the switching tube subcircuit is electrically connected with an optocoupler transmission subcircuit, and the optocoupler transmission subcircuit outputs a sampling voltage, wherein the sampling voltage is used for controlling an AD-DC power supply to adjust the direct current voltage output to the fast charging adapter, so that the pressure difference between the direct current voltage output to the fast charging adapter and the current highest output voltage of the output end of the fast charging adapter is within a preset pressure difference range, the input voltage of the fast charging adapter is adjusted by following the output voltage of the fast charging adapter, and the energy consumption and heat generation of the fast charging charger are reduced.

Description

Technical Field

[0001] This invention mainly relates to the field of fast charging technology, specifically to an output voltage follower feedback circuit and a fast charger. Background Technology

[0002] Generally, fast charging requires an AD-DC power supply and a fast charging adapter. The AD-DC power supply converts AC to DC, and its output voltage to the fast charging adapter is fixed. This fixed voltage powers the fast charging adapter to perform boost or buck conversion to the output. Since the output voltage conversion range is relatively wide (e.g., PD fast charging, with an output voltage range of 3.3V to 20V), the fixed supply voltage of the AD-DC power supply must be greater than the maximum output voltage, i.e., greater than 20V. This limitation means that when the output voltage is relatively low (e.g., 9V, 5V, 3.3V, etc.), the fixed supply voltage of the AD-DC power supply (greater than 20V) results in a large voltage difference between the input and output voltages of the fast charging adapter. This leads to a rapid decrease in the fast charging adapter's conversion efficiency, severe heat generation, and increased temperature.

[0003] Therefore, a voltage follower feedback circuit and a fast charger are needed to provide feedback on the output voltage of the fast charger adapter, and also to facilitate the adjustment of the input voltage of the fast charger adapter by following the output voltage of the fast charger adapter, thereby reducing the energy consumption and heat generation of the fast charger adapter. Summary of the Invention

[0004] One embodiment of this specification provides an output voltage follower feedback circuit, including: a diode sampling sub-circuit, a Zener diode feedback circuit, a switching transistor circuit, and an optocoupler transmission sub-circuit. The diode sampling sub-circuit is used to collect the voltage at the output terminal of the fast charging adapter. The output terminal of the diode sampling sub-circuit is electrically connected to the input terminal of the Zener diode feedback circuit. The output terminal of the Zener diode feedback circuit is electrically connected to the control terminal of the switching transistor circuit. The switching transistor circuit is electrically connected to the optocoupler transmission sub-circuit. The optocoupler transmission sub-circuit is used to output a feedback voltage. This feedback voltage is used to control the AD-DC power supply to adjust the DC voltage output to the fast charging adapter, ensuring that the voltage difference between the DC voltage output to the fast charging adapter and the current highest output voltage at the fast charging adapter's output terminal is within a preset voltage difference range.

[0005] In some embodiments, the diode sampling sub-circuit includes at least one diode, the number of diodes being the same as the number of output terminals of the fast charging adapter, the anode of the diode being electrically connected to the output terminal of the fast charging adapter, and the cathode of the diode being electrically connected to the Zener diode feedback circuit.

[0006] In some embodiments, the Zener diode feedback circuit includes a Zener diode, the cathodes of the at least one diode are electrically connected to the cathode of the Zener diode, and the anode of the Zener diode is electrically connected to the control terminal of the switching transistor circuit.

[0007] In some embodiments, the Zener diode feedback circuit includes two or more Zener diodes connected in parallel, the cathode of at least one of the diodes is electrically connected to the cathode of the two or more Zener diodes connected in parallel, the anode of the two or more Zener diodes connected in parallel is electrically connected to the control terminal of the switching transistor circuit, and the number of Zener diodes is consistent with the number of output voltage levels of the fast charging adapter.

[0008] In some embodiments, the switching transistor circuit includes two or more switching transistor units connected in parallel, the number of switching transistor units being the same as the number of Zener diodes, one Zener diode corresponding to one switching transistor unit, and the positive terminal of the Zener diode being electrically connected to the control terminal of the corresponding switching transistor unit.

[0009] In some embodiments, the switching transistor unit includes a switching transistor and a resistor, the anode of the Zener diode is electrically connected to the control terminal of the switching transistor, one end of the resistor is electrically connected to the optocoupler transmission sub-circuit, and the switching transistor is connected in series between the other end of the resistor and the ground terminal.

[0010] In some embodiments, the switching transistor is a MOSFET or an NPN transistor.

[0011] One embodiment of this specification provides a fast charger, comprising: an AD-DC power supply for AC-DC conversion to provide DC power to a fast charger adapter; the fast charger adapter for voltage conversion of the DC power provided by the AD-DC power supply to fast charge a load; the charger further comprising an output voltage following feedback circuit as described in any one of claims 1-7, wherein the input terminal of the output voltage following feedback circuit is electrically connected to the output terminal of the fast charger adapter, and the output terminal of the output voltage following feedback circuit is electrically connected to the input terminal of the AD-DC power supply; the output voltage following feedback circuit is used to sample the voltage at the output terminal of the fast charger adapter and output a feedback voltage; the AD-DC power supply is further used to adjust the DC voltage output to the fast charger adapter according to the feedback voltage, such that the voltage difference between the DC voltage output to the fast charger adapter and the current highest output voltage at the output terminal of the fast charger adapter is within a preset voltage difference range. Attached Figure Description

[0012] This application will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting; in these embodiments, the same reference numerals denote the same structures, wherein:

[0013] Figure 1 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 1 of this application;

[0014] Figure 2 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 2 of this application;

[0015] Figure 3 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 3 of this application;

[0016] Figure 4 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 4 of this application;

[0017] Figure 5 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 5 of this application;

[0018] Figure 6 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment Six of this application;

[0019] Figure 7 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 7 of this application;

[0020] Figure 8 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 8 of this application.

[0021] In the diagram, 110 is the diode sampling sub-circuit; 120 is the Zener diode feedback circuit; 130 is the switching transistor sub-circuit; 131 is the switching transistor unit; and 140 is the optocoupler transmission sub-circuit. Detailed Implementation

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. It should be understood that these exemplary embodiments are given merely to enable those skilled in the art to better understand and implement the present invention, and are not intended to limit the scope of the present invention in any way. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0023] It should be understood that the terms “system,” “device,” “unit,” and / or “module” used herein are one way to distinguish different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they may be replaced by other expressions.

[0024] As illustrated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list; the method or apparatus may also include other steps or elements. While this application makes various references to certain modules or units in systems according to embodiments of this application, any number of different modules or units may be used and run on clients and / or servers. The modules are merely illustrative, and different aspects of the systems and methods may use different modules.

[0025] In some embodiments, the circuit includes a diode sampling sub-circuit 110, a Zener diode feedback circuit 120, a switching transistor circuit 130, and an optocoupler transmission sub-circuit 140. The diode sampling sub-circuit 110 is used to collect the voltage at the output terminal of the fast charging adapter. The output terminal of the diode sampling sub-circuit 110 is electrically connected to the input terminal of the Zener diode feedback circuit 120. The output terminal of the Zener diode feedback circuit 120 is electrically connected to the control terminal of the switching transistor circuit 130. The switching transistor circuit 130 is electrically connected to the optocoupler transmission sub-circuit 140. The optocoupler transmission sub-circuit 140 is used to output a feedback voltage. This feedback voltage is used to control the AD-DC power supply to adjust the DC voltage output to the fast charging adapter, ensuring that the voltage difference between the DC voltage output to the fast charging adapter and the current highest output voltage at the output terminal of the fast charging adapter is within a preset voltage difference range.

[0026] In some embodiments, the diode sampling sub-circuit 110 may include at least one diode, the number of diodes being the same as the number of output terminals of the fast charging adapter. For example, Figure 1 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 1 of this application. Figure 2 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 2 of this application. Figure 3 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 3 of this application, as shown below. Figures 1 to 3As shown, when the number of output terminals of the fast charging adapter is 2, the number of diodes is also 2; when the number of output terminals of the fast charging adapter is 3, the number of diodes is also 3; when the number of output terminals of the fast charging adapter is 5, the number of diodes is also 5. The positive terminal of the diode is electrically connected to the output terminal of the fast charging adapter, and the negative terminal of the diode is electrically connected to the Zener diode feedback circuit 120. The voltage of the output terminal of the fast charging adapter is transmitted to the Zener diode feedback circuit 120 through the diode.

[0027] like Figures 1 to 3 As shown, in some embodiments, when the output voltage level of the fast charging adapter is unique, the Zener diode feedback circuit 120 may include a Zener diode, with the negative terminal of at least one diode electrically connected to the negative terminal of the Zener diode, and the positive terminal of the Zener diode electrically connected to the control terminal of the switching transistor circuit 130. The voltage of each output terminal of the fast charging adapter is transmitted to the Zener diode through the diode.

[0028] like Figures 1 to 3 As shown, when the output voltage level of the fast charging adapter is unique, the switching transistor sub-circuit 130 includes only one switching transistor unit 131. The switching transistor unit 131 may include a switching transistor and a resistor. The positive terminal of the Zener diode is electrically connected to the control terminal of the switching transistor. One end of the resistor is electrically connected to the optocoupler transmission sub-circuit 140. The switching transistor is connected in series between the other end of the resistor and the ground terminal.

[0029] Understandably, when the output voltage levels of the fast charging adapter are not unique, the number of Zener diodes included in the Zener diode feedback circuit 120 is also not unique. In some embodiments, the Zener diode feedback circuit 120 includes two or more Zener diodes connected in parallel, wherein the number of Zener diodes is consistent with the number of output voltage levels of the fast charging adapter. The cathode of at least one diode is electrically connected to the cathode of the two or more Zener diodes connected in parallel, and the anode of the two or more Zener diodes connected in parallel is electrically connected to the control terminal of the switching transistor circuit 130. For example, Figure 4 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 4 of this application, as shown below. Figure 4 As shown, when the fast charging adapter has two output voltage levels, the number of Zener diodes is also two. For example, Figure 5 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 5 of this application. Figure 6 This is a circuit diagram of the output voltage follower feedback circuit shown in Embodiment Six of this application. Figure 7 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 7 of this application. Figure 8 This is a circuit diagram of the output voltage follower feedback circuit according to Embodiment 8 of this application, as shown below. Figures 5-8As shown, when the fast charging adapter has 5 output voltage levels, the number of Zener diodes is also 5.

[0030] like Figure 7 , Figure 8 As shown, the switching transistor can be an N-MOS transistor or an NPN transistor.

[0031] When the output voltage levels of the fast charging adapter are not unique, the switching transistor circuit 130 may include two or more parallel switching transistor units 131. The number of switching transistor units 131 is the same as the number of Zener diodes, with one Zener diode corresponding to one switching transistor unit 131. The anode of the Zener diode is electrically connected to the control terminal of the corresponding switching transistor unit 131. For example, as... Figure 4 As shown, the output terminal of the first Zener diode ZD1 is electrically connected to the control terminal of the switch transistor in a switching unit 131, and the output terminal of the second Zener diode ZD2 is also electrically connected to the control terminal of the switch transistor in the switching unit 131. For example, as... Figure 5 As shown, the output terminal of the first Zener diode ZD1 is electrically connected to the control terminal of the switch of a switching transistor unit 131; the output terminal of the second Zener diode ZD2 is electrically connected to the control terminal of the switch of a switching transistor unit 131; the output terminal of the third Zener diode ZD3 is electrically connected to the control terminal of the switch of a switching transistor unit 131; the output terminal of the fourth Zener diode ZD4 is electrically connected to the control terminal of the switch of a switching transistor unit 131; and the output terminal of the fifth Zener diode ZD5 is electrically connected to the control terminal of the switch of a switching transistor unit 131.

[0032] In some embodiments, a fast charger may include: an AD-DC power supply, a fast charger adapter, and an output voltage follower feedback circuit. The various parts of the fast charger will be described in turn below.

[0033] AD-DC power supplies can be used to perform AC-DC conversion and provide DC power to fast charging adapters.

[0034] Fast charging adapters can be used to convert the DC power supplied by an AD-DC power supply to fast charge the load.

[0035] The input terminal of the output voltage follower feedback circuit is electrically connected to the output terminal of the fast charging adapter, and the output terminal of the output voltage follower feedback circuit is electrically connected to the input terminal of the AD-DC power supply. The output voltage follower feedback circuit is used to sample the voltage at the output terminal of the fast charging adapter and output a feedback voltage.

[0036] The AD-DC power supply can also be used to adjust the DC voltage output to the fast charging adapter based on the feedback voltage, so that the voltage difference between the DC voltage output to the fast charging adapter and the current highest output voltage at the output terminal of the fast charging adapter is within a preset voltage difference range.

[0037] Understandably, a fast charging adapter can be electrically connected to a terminal device (e.g., a mobile phone, computer, etc.) via a port. The terminal device can send the required charging voltage value to the fast charging adapter's protocol chip or circuit through the port. After receiving the required charging voltage value from the terminal device, the protocol chip or circuit can adjust the output voltage of the fast charging adapter accordingly. When the terminal device does not send the required charging voltage value to the fast charging adapter's protocol chip or circuit, the output voltage of the fast charging adapter can be a preset low voltage. When the protocol chip or protocol circuit receives a charging voltage value from the terminal device that is higher than the preset low voltage, the voltage at the output terminal of the fast charging adapter (e.g., one or any combination of VOUT1, VOUT2, VOUT3, VOUT4, VOUT5, etc.) increases. The voltages at each output terminal of the fast charging adapter are directionally transmitted to the Zener diode via diodes. After the output voltage at the fast charging adapter increases and exceeds the rated voltage of the Zener diode, the Zener diode reverse-biased conduction occurs, applying a turn-on voltage to the gate (G) of the N-MOS transistor or the base (B) of the NPN transistor in the switching transistor unit 131. The switching transistor then turns on, thus enabling the optocoupler transmission sub-circuit. The fifth resistor R5 of 140 is connected in parallel with the resistor of the switching transistor unit 131. This changes the output voltage sampling bias of the feedback voltage, changes the feedback of U2, and changes the transmission of the optocoupler U1. The AD-DC power supply adjusts the DC voltage output to the fast charging adapter according to the feedback voltage, so that the voltage difference between the DC voltage output to the fast charging adapter and the output voltage of the fast charging adapter is within a preset voltage difference range. In this way, the AD-DC power supply adjusts the DC voltage output to the fast charging adapter according to the feedback voltage, and changes it with the voltage VOUT of the fast charging adapter's output terminal, adjusting it to a suitable supply voltage to improve the efficiency of different voltage ranges, reduce heat generation, and reduce energy consumption.

[0038] In some embodiments, when multiple output terminals of the fast charging adapter are connected to loads for charging, and the output voltage of each output terminal is different, the AD-DC power supply adjusts the DC voltage output to the fast charging adapter according to the feedback voltage, so that the voltage difference between the DC voltage output to the fast charging adapter and the current highest output voltage of the fast charging adapter's output terminal is within a preset voltage difference range.

[0039] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.

[0040] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0041] Furthermore, those skilled in the art will understand that aspects of this application can be described and illustrated in several patentable kinds or situations, including any new and useful combination of processes, machines, products or substances, or any new and useful improvements thereto.

[0042] Furthermore, unless expressly stated in the claims, the order of elements and sequences processed in this application, the use of numbers and letters, or the use of other names are not intended to limit the order of the processes and methods of this application. Although the foregoing disclosure has discussed some currently considered useful embodiments of the invention through various examples, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments; rather, the claims are intended to cover all modifications and equivalent combinations that conform to the substance and scope of the embodiments of this application. For example, while the system components described above can be implemented by hardware devices, they can also be implemented solely by software solutions, such as installing the described system on existing servers or mobile devices.

[0043] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0044] Finally, it should be understood that the embodiments described in this application are merely illustrative of the principles of the embodiments of this application. Other modifications may also fall within the scope of this application. Therefore, alternative configurations of the embodiments of this application are considered as examples and not limitations, and are regarded as consistent with the teachings of this application. Accordingly, the embodiments of this application are not limited to the embodiments explicitly described and illustrated in this application.

Claims

1. An output voltage follower feedback circuit, characterized in that, include: The system comprises a diode sampling sub-circuit, a Zener diode feedback circuit, a switching transistor circuit, and an optocoupler transmission sub-circuit. The diode sampling sub-circuit is used to acquire the voltage at the output terminal of the fast charging adapter. The output terminal of the diode sampling sub-circuit is electrically connected to the input terminal of the Zener diode feedback circuit. The output terminal of the Zener diode feedback circuit is electrically connected to the control terminal of the switching transistor circuit. The switching transistor circuit is electrically connected to the optocoupler transmission sub-circuit. The optocoupler transmission sub-circuit is used to output a feedback voltage. This feedback voltage controls the AD-DC power supply to adjust the DC voltage output to the fast charging adapter, ensuring that the voltage difference between the DC voltage output to the fast charging adapter and the current highest output voltage at the fast charging adapter's output terminal is within a preset voltage difference range. When the output voltage of the fast charging adapter is unique, the Zener diode feedback circuit includes a Zener diode, at least one diode's cathode is electrically connected to the cathode of the Zener diode, and the Zener diode's anode is electrically connected to the control terminal of the switching transistor circuit. The voltage of each output terminal of the fast charging adapter is transmitted to the Zener diode through the diode. The switching transistor circuit includes only one switching transistor unit, which includes a switching transistor and a resistor. The anode of the Zener diode is electrically connected to the control terminal of the switching transistor, one end of the resistor is electrically connected to the optocoupler transmission sub-circuit, and the switching transistor is connected in series between the other end of the resistor and the ground terminal. When the output voltage level of the fast charging adapter is not unique, the number of Zener diodes included in the Zener diode feedback circuit is also not unique. The switching transistor circuit includes at least two parallel switching transistor units. The number of switching transistor units is the same as the number of Zener diodes. One Zener diode corresponds to one switching transistor unit. The positive terminal of the Zener diode is electrically connected to the control terminal of the corresponding switching transistor unit. The fast charging adapter is electrically connected to the terminal device via a port. The terminal device sends the required charging voltage value to the protocol chip or protocol circuit of the fast charging adapter through the port. After receiving the required charging voltage value from the terminal device, the protocol chip or protocol circuit adjusts the output voltage of the fast charging adapter according to the required charging voltage value. When the required charging voltage value sent by the terminal device is higher than the preset low voltage, the output voltage of the fast charging adapter increases. The voltages of each output terminal of the fast charging adapter are directionally transmitted to the Zener diode through diodes. After the output voltage of the fast charging adapter increases, it exceeds the rated voltage of the Zener diode. The voltage regulator diode is reverse-biased, and when an on-state voltage is applied to the switching transistor unit, the switching transistor unit conducts. The fifth resistor of the optocoupler transmission sub-circuit is connected in parallel with the resistor of the switching transistor unit. Changing the output voltage sampling bias of the feedback voltage changes the optocoupler transmission. The AD-DC power supply adjusts the DC voltage output to the fast charging adapter according to the feedback voltage, so that the voltage difference between the DC voltage output to the fast charging adapter and the output voltage at the fast charging adapter terminal is within a preset voltage difference range. This achieves the effect that the AD-DC power supply adjusts the DC voltage output to the fast charging adapter according to the feedback voltage, which changes with the voltage VOUT at the output terminal of the fast charging adapter, thus adjusting the supply voltage.

2. The output voltage follower feedback circuit according to claim 1, characterized in that, The diode sampling sub-circuit includes at least one diode, the number of which is the same as the number of output terminals of the fast charging adapter. The positive terminal of the diode is electrically connected to the output terminal of the fast charging adapter, and the negative terminal of the diode is electrically connected to the Zener diode feedback circuit.

3. The output voltage follower feedback circuit according to claim 2, characterized in that, The Zener diode feedback circuit includes a Zener diode, the cathode of each of the at least one diode is electrically connected to the cathode of the Zener diode, and the anode of the Zener diode is electrically connected to the control terminal of the switching transistor circuit.

4. The output voltage follower feedback circuit according to claim 2, characterized in that, The Zener diode feedback circuit includes at least two Zener diodes connected in parallel. The cathode of at least one of the Zener diodes is electrically connected to the cathode of the at least two Zener diodes connected in parallel. The anode of the at least two Zener diodes connected in parallel is electrically connected to the control terminal of the switching transistor circuit. The number of Zener diodes is consistent with the number of output voltage levels of the fast charging adapter.

5. The output voltage follower feedback circuit according to claim 4, characterized in that, The switching transistor sub-circuit includes at least two switching transistor units connected in parallel. The number of switching transistor units is the same as the number of Zener diodes. One Zener diode corresponds to one switching transistor unit. The positive terminal of the Zener diode is electrically connected to the control terminal of the corresponding switching transistor unit.

6. The output voltage follower feedback circuit according to claim 5, characterized in that, The switching transistor unit includes a switching transistor and a resistor. The positive terminal of the Zener diode is electrically connected to the control terminal of the switching transistor. One end of the resistor is electrically connected to the optocoupler transmission sub-circuit. The switching transistor is connected in series between the other end of the resistor and the ground terminal.

7. The output voltage follower feedback circuit according to claim 6, characterized in that, The switching transistor is an N-MOS transistor or an NPN transistor.

8. A fast charger, characterized in that, include: AD-DC power supply is used to perform AC-DC conversion and provide DC power to the fast charging adapter; The fast charging adapter is used to convert the DC power supplied by the AD-DC power supply to a voltage, and to fast charge the load. It also includes the output voltage follower feedback circuit as described in any one of claims 1-7, wherein the input terminal of the output voltage follower feedback circuit is electrically connected to the output terminal of the fast charging adapter, the output terminal of the output voltage follower feedback circuit is electrically connected to the input terminal of the AD-DC power supply, and the output voltage follower feedback circuit is used to sample the voltage at the output terminal of the fast charging adapter and output a feedback voltage; The AD-DC power supply is also used to adjust the DC voltage output to the fast charging adapter according to the feedback voltage, so that the voltage difference between the DC voltage output to the fast charging adapter and the current highest output voltage at the output terminal of the fast charging adapter is within a preset voltage difference range.

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