CN222191895U - Charging circuit and charging device - Google Patents
Charging circuit and charging device Download PDFInfo
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- CN222191895U CN222191895U CN202323239217.1U CN202323239217U CN222191895U CN 222191895 U CN222191895 U CN 222191895U CN 202323239217 U CN202323239217 U CN 202323239217U CN 222191895 U CN222191895 U CN 222191895U
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Abstract
The embodiment of the application discloses a charging circuit and a charging device, wherein the charging circuit comprises a transformer, a first output circuit, a second output circuit and a control circuit, the transformer is provided with a primary winding, a first secondary winding and a second secondary winding, the first secondary winding and the second secondary winding are arranged corresponding to the primary winding, the first output circuit comprises a first output port connected with the output end of the first secondary winding, the second output circuit comprises a direct current-to-direct current converter and a second output port which are connected with each other, the input end of the direct current-to-direct current converter is connected with the output end of the second secondary winding, and the control circuit is connected with the output end of the first secondary winding, the first output circuit and the second output circuit.
Description
Technical Field
The application relates to the technical field of charging devices, in particular to a charging circuit and a charging device.
Background
Nowadays, intelligent devices needing to be charged in daily life are increasingly increased, and intelligent devices such as smart phones, notebook computers, tablet computers and the like, and electric tools, cordless dust collectors, vehicle dust collectors and the like supporting mainstream fast charging protocols are required to be charged rapidly, so that a multi-port charging device is derived from the technology of the traditional single-port charging device. Because the required voltage of the electric equipment connected to each charging port is different, a direct current-to-direct current converter needs to be arranged on the circuit corresponding to each charging port, so that the output voltage of each charging port can be changed according to the required voltage of the electric equipment, but the output efficiency of the charging equipment is lower due to the fact that more direct current-to-direct current converters are arranged.
Disclosure of utility model
The embodiment of the application provides a charging circuit and a charging device, which aim to save line loss caused by a direct current-to-direct current converter without using the direct current-to-direct current converter in a first output circuit, so that the output efficiency of the first output circuit can be improved, and the output efficiency of the charging circuit is further improved.
The embodiment of the application provides a charging circuit which comprises a transformer, a first output circuit, a second output circuit and a control circuit, wherein the transformer is provided with a primary winding, a first secondary winding and a second secondary winding, the first secondary winding and the second secondary winding are arranged corresponding to the primary winding, the first output circuit comprises a first output port connected with the output end of the first secondary winding, the second output circuit comprises a direct current-direct current converter and a second output port which are connected with each other, the input end of the direct current-direct current converter is connected with the output end of the second secondary winding, the control circuit is connected with the output end of the first secondary winding, the first output circuit and the second output circuit, and the control circuit is used for adjusting the bus voltage of the output end of the first secondary winding according to the output voltage of the first output circuit and the output voltage of the second output circuit.
Based on the above embodiment, since the first output circuit is not provided with the dc-dc converter compared with the output circuit in the related art, the line loss caused by the dc-dc converter can be saved, so that the output efficiency of the first output circuit can be improved to improve the overall output efficiency of the charging circuit, and since the first output circuit is not provided with the dc-dc converter, the space occupation of the first output circuit can be reduced to reduce the volume of the charging circuit, so that the volume of the charging device can be reduced. When the control circuit detects that at least one of the output voltage of the first output circuit and the output voltage of the second output circuit is larger than the bus voltage of the output end of the first secondary winding, the bus voltage of the output end of the first secondary winding can be boosted, so that the bus voltage of the first secondary winding is closer to the output voltage of the first output end, the output efficiency of the first output circuit is improved, and further, the bus voltage of the output end of the first secondary winding is increased, the magnetic flux of the first secondary winding in the iron core is increased according to the electromagnetic induction principle, the bus voltage of the second secondary winding is synchronously increased, the increasing proportion is the turn ratio of the first secondary winding to the second secondary winding, and when the bus voltage of the second secondary winding is increased, the bus voltage of the second secondary winding is close to the output voltage of the second output end, so that the output efficiency of the second output circuit is improved, and the output efficiency of the charging circuit is improved.
The embodiment of the application also provides a charging device which comprises a shell, a circuit board and a charging circuit, wherein the circuit board is arranged in the shell, and the charging circuit is arranged on the circuit board.
According to the charging circuit, the transformer comprises the primary winding and the first winding and the second winding which are arranged corresponding to the primary winding, the first winding and the second winding are respectively connected with the first output circuit and the second output circuit, and compared with the output circuit in the related art, the first output circuit is not provided with the direct current-to-direct current converter, so that the circuit loss caused by the direct current-to-direct current converter can be reduced, the output efficiency of the first output circuit can be improved, the overall output efficiency of the charging circuit can be improved, and the space occupation of the first output circuit can be reduced due to the fact that the direct current-to-direct current converter is not arranged in the first output circuit, the size of the charging circuit can be reduced, and the size of the charging device can be reduced.
Drawings
In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings that are necessary for the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the application and that other drawings may be obtained from them without inventive effort for a person skilled in the art.
Fig. 1 is a schematic structural diagram of a charging device according to an embodiment of the present application;
FIG. 2 is a schematic diagram of a frame structure of a charging circuit according to an embodiment of the application;
fig. 3 is a schematic diagram of a charging circuit according to an embodiment of the application.
The reference numerals indicate 1, a charging device, 11, a shell, 12, a circuit board, 13, a charging circuit, 131, a transformer, 132, a first output circuit, 132A, a first output port, 1321, a first protocol chip, 133, a second output circuit, 133A, a second output port, 1331, a direct current-to-direct current converter, 1332, a second protocol chip, 134, a control circuit, 1341, a controller, 1342, a boosting circuit, 13421, a sampling circuit, 13421A, a sampling output end, 13422, a voltage stabilizing circuit, 13423, a switching circuit, N0, a primary winding, N1, a first secondary winding, N2, a second secondary winding, R1, a first resistor, R2, a second resistor, R3, a third resistor, R4, a fourth resistor, R5, a fifth resistor, K1, a controllable precision voltage stabilizing source, Q1 and a switching element.
Detailed Description
The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.
Referring to fig. 1, an embodiment of the present application provides a charging device 1, which includes a housing 11, a circuit board 12 and a charging circuit 13.
The shell 11 can support and protect the electronic components in the shell 11, and the material of shell 11 can be plastics or metal, and specifically, the material of shell 11 can be plastics to make shell 11 insulating, thereby can reduce the risk of user's electric shock, and because plastics material quality is lighter, so that shell 11 quality is lighter, thereby makes charging device 1 holistic quality lighter, in order to portable charging device 1. Specifically, the casing 11 may be integrally injection molded, so that the casing 11 has higher structural strength, so that the casing 11 is not easy to be damaged, and other parts in the casing 11 can be protected, so that the probability of damage of other parts is reduced, and the charging device 1 has a longer service life.
The housing 11 further has A plurality of charging ports, and the charging device 1 can be connected to the mains supply and supply power to electric equipment viA the charging ports, wherein the electric equipment comprises, but is not limited to, A mobile phone, A tablet computer and A smart watch, and the charging ports comprise at least one of A USB-A interface, A Micro USB interface, A USB Type-C interface or A Lightning interface.
The charging circuit 13 may be formed on the circuit board 12 by an etching process, so that the manufacturing efficiency of the charging circuit 13 may be improved, and the manufacturing cost of the charging circuit 13 may be reduced.
Referring to fig. 1 and 2, in a specific embodiment, the charging circuit 13 includes a transformer 131, a first output circuit 132, a second output circuit 133, and a control circuit 134.
The transformer 131 has a primary winding N0, a first secondary winding N1, and a second secondary winding N2, and the first secondary winding N1 and the second secondary winding N2 are disposed corresponding to the primary winding N0. When the charging device 1 is connected with alternating current, the alternating current is connected with the primary winding N0 through the rectifier and the filter, and a magnetic field is generated in the magnetic core, and the alternating current is electromagnetically induced to the first secondary winding N1 and the second secondary winding N2, so that the first secondary winding N1 and the second secondary winding N2 can output voltage. It can be understood that the primary winding N0 is further connected to a frequency modulation circuit, so that the output voltage of the primary winding N0 can be changed, which is not described herein.
The first output circuit 132 includes a first output port 132A connected to the output of the first secondary winding N1, such that the first output port 132A may supply power to a powered device. The first output port 132A includes at least one of A USB Type-C port and A USB-A port.
The second output circuit 133 includes a dc-dc converter 1331 and a second output port 133A, which are connected to each other, wherein an input end of the dc-dc converter 1331 is connected to an output end of the second secondary winding N2, and the dc-dc converter 1331 can convert the secondary winding into an output voltage required by the second output port 133A and supply power to the second output port 133A, so that the second output port 133A supplies power to the electric device. It will be appreciated that the output end of the second secondary winding N2 may be connected in parallel with a plurality of second output circuits 133, so as to have a plurality of second output ports 133A, so as to be able to supply power to different electric devices. It is understood that the transformer 131 may have a plurality of second secondary windings N2, and the output terminals of the plurality of second secondary windings N2 may be connected to at least one second output circuit 133. In the embodiment of the present application, the number of the second secondary windings N2 is not particularly limited, and the number of the second output circuits 133 is not particularly limited either. The second output port 133A includes at least one of A USB Type-C port and A USB-A port.
The control circuit 134 is connected to the output terminal of the first secondary winding N1, the first output circuit 132 and the second output circuit 133, and the control circuit 134 is configured to adjust the bus voltage of the output terminal of the first secondary winding N1 according to the output voltages of the first output circuit 132 and the second output circuit 133, so as to raise the bus voltage of the output terminal of the first secondary winding N1, and raise the bus voltage of the output terminal of the second secondary winding N2. When the multiple ports are simultaneously output differently, the pressure difference of the whole voltage range is reduced, and the efficiency of the whole system is improved.
In another embodiment, the control circuit 134 may also be connected to the output terminal of the second secondary winding N2, for adjusting the bus voltage of the output terminal of the second secondary winding N2 according to the output voltages of the first output circuit 132 and the second output circuit 133, so as to raise the bus voltage of the output terminal of the second secondary winding N2, and raise the bus voltage of the output terminal of the first secondary winding N1. The circuit composition structure is the same as that of the above embodiment, and the description of this embodiment is omitted.
In the embodiment of the present application, compared with the output circuit in the related art, the first output circuit 132 is not provided with the dc-dc converter 1331, so that the line loss caused by the dc-dc converter 1331 can be saved, the output efficiency of the first output circuit 132 can be improved, the overall output efficiency of the charging circuit 13 can be improved, and the space occupation of the first output circuit 132 can be reduced due to the fact that the first output circuit 132 is not provided with the dc-dc converter 1331, the volume of the charging circuit 13 can be reduced, and the volume of the charging device 1 can be reduced. When the control circuit 134 detects that at least one of the output voltage of the first output circuit 132 and the output voltage of the second output circuit 133 is greater than the bus voltage of the output end of the first secondary winding N1, the bus voltage of the output end of the first secondary winding N1 may be boosted, so that the bus voltage of the first secondary winding N1 is closer to the output voltage of the first output port 132A, so as to improve the output efficiency of the first output circuit 132, and further, since the first secondary winding N1 and the second secondary winding N2 are wound on the same core, the bus voltage of the output end of the first secondary winding N1 is increased according to the electromagnetic induction principle. The magnetic flux of the first secondary winding N1 in the iron core is increased, so that the bus voltage of the second secondary winding N2 is synchronously increased, the increasing ratio is the turn ratio of the first secondary winding N1 to the second secondary winding N2, and when the bus voltage of the second secondary winding N2 is increased, the bus voltage of the second secondary winding N2 is also close to the output voltage of the second output port 133A, so that the output efficiency of the second output circuit 133 is also improved, and the output efficiency of the charging circuit 13 is further improved.
Referring to fig. 1-3, in a specific embodiment, the first output circuit 132 includes a first protocol chip 1321, the first protocol chip 1321 is connected in series between the first secondary winding N1 and the first output port 132A, the second output circuit 133 includes a second protocol chip 1332, and the second protocol chip 1332 is connected in series between the dc-dc converter 1331 and the second output port 133A. When the electric device is connected with the first output port 132A, information interaction is performed between the electric device and the first protocol chip 1321, so that the first protocol chip 1321 controls the first output circuit 132 to output a power supply voltage required by the electric device within a preset range, and when the electric device is connected with the second output port 133A, information interaction is performed between the electric device and the second protocol chip 1332, so that the second protocol chip 1332 controls the output end of the direct current-to-direct current converter 1331 to output the power supply voltage required by the electric device.
Referring to fig. 1-3, in a specific embodiment, the control circuit 134 further includes a controller 1341 and a boost circuit 1342, the controller 1341 may be the controller 1341 of the charging circuit 13, or may be the controller 1341 of the charging device 1, and in this embodiment, the specific form of the controller 1341 is not limited. The controller 1341 is connected to the first output circuit 132 and the second output circuit 133, and is configured to detect an output voltage of the first output circuit 132. For example, the controller 1341 may be connected to the first output port 132A and the second output port 133A to detect output voltages of the first output port 132A and the second output port 133A. The controller 1341 may be further connected to the first protocol chip 1321 and the second protocol chip 1332, so that the controller 1341 may obtain the protocol information of the first protocol chip 1321 and the second protocol chip 1332, and may also obtain the output voltages of the first output port 132A and the second output port 133A. In the embodiment of the present application, the form in which the controller 1341 obtains the output voltage from the first output circuit 132 and the second output circuit 133 is not particularly limited.
Referring to fig. 3, the boost circuit 1342 is connected to the output end of the first secondary winding N1 and the controller 1341, when the controller 1341 detects that the voltages of the first output port 132A and the second output port 133A are higher than the bus voltage of the first secondary winding N1, the controller 1341 controls the boost circuit 1342 to operate so as to raise the bus voltage of the first secondary winding N1, so that when the output voltage of the first output port 132A is higher than the bus voltage of the first secondary winding N1, the bus voltage of the first secondary winding N1 is closer to the output voltage of the first output port 132A, and the output efficiency of the first output circuit 132 is improved, and because the bus voltage of the first secondary winding N1 is raised, the bus voltage of the second secondary winding N2 is also raised, so that the bus voltage of the second secondary winding N2 is closer to the output voltage of the second output port 133A, and the output efficiency of the second output circuit 133 is improved.
Referring to fig. 3, in a specific embodiment, the boost circuit 1342 includes a sampling circuit 13421, a voltage stabilizing circuit 13422 and a switching circuit 13423, wherein the sampling circuit 13421 is connected to the output end of the first secondary winding N1 and has a sampling output end 13421A, and the voltage stabilizing circuit 13422 is connected to the output end of the first secondary winding N1 and is connected to the sampling output end 13421A, so as to dynamically stabilize the bus voltage of the output end of the first secondary winding N1 according to the voltage of the sampling output end 13421A. The switching circuit 13423 is connected to the sampling output 13421A and to the controller 1341, and is controlled by the controller 1341 to raise the bus voltage when the switching circuit 13423 is controlled to be turned on.
Referring to fig. 3, in a specific embodiment, the sampling circuit 13421 includes a first resistor R1 and a second resistor R2, a first end of the first resistor R1 is connected to an output end of the first secondary winding N1, a first end of the second resistor R2 is connected to a second end of the first resistor R1, a second end of the second resistor R2 is grounded, a first end of the second resistor R2 is a sampling output end 13421A, and a sampling voltage is output from the sampling output end 13421A after the bus voltage of the first secondary winding N1 is divided by the first resistor R1 and the second resistor R2.
Referring to fig. 3, in a specific embodiment, the voltage stabilizing circuit 13422 includes a third resistor R3 and a controllable precise voltage stabilizing source K1, wherein a first end of the third resistor R3 is connected to an output end of the first secondary winding N1, a negative electrode of the controllable precise voltage stabilizing source K1 is connected to a second end of the third resistor R3, a positive electrode of the controllable precise voltage stabilizing source K1 is grounded, a reference electrode of the controllable precise voltage stabilizing source K1 is connected to the sampling output end 13421A, and the third resistor R3 is used for limiting the current of the controllable precise voltage stabilizing source K1 to prevent the controllable precise voltage stabilizing source K1 from being burned out by a large current, so that the controllable precise voltage stabilizing source K1 has a longer service life.
Referring to fig. 3, an exemplary controllable precision voltage-stabilizing source K1 may be a TL431 controllable precision voltage-stabilizing source K1, when the bus voltage at the output end of the first secondary winding N1 is higher than a preset value, after the voltage is divided by the first resistor R1 and the second resistor R2, the sampled voltage at the output end 13421A is increased, so that the reference level voltage of the controllable precision voltage-stabilizing source K1 is increased, when the sampled voltage is higher than the reference level voltage, the negative electrode and the positive electrode of the controllable precision voltage-stabilizing source K1 are conducted, so that the bus voltage at the output end of the first secondary winding N1 is reduced, so that the sampled voltage at the sampling output end 13421A is reduced, and when the sampled voltage is lower than the reference voltage, the bus voltage at the output end of the first secondary winding N1 is increased, the above process is repeated, so that the sampled voltage is dynamically stabilized at the reference voltage, so that the preset voltage at the output end of the first secondary winding N1 is dynamically stabilized at the first secondary winding dynamically, and the bus voltage is dynamically stabilized at the preset value of the first secondary winding N1 is realized.
It is understood that the bus voltage at the output end of the first secondary winding N1 is determined by the resistances of the first resistor R1 and the second resistor R2, and the resistances of the first resistor R1 and the second resistor R2 can be set according to the maximum output voltage of the first output end 132A, and in the embodiment of the present application, the resistances of the first resistor R1 and the second resistor R2 are not particularly limited.
Referring to fig. 3, in a specific embodiment, the switching circuit 13423 includes a fourth resistor R4 and a switching element Q1 connected in series, and a controlled end of the switching element Q1 is connected to the controller 1341.
When the controller 1341 detects that at least one bus voltage higher than the first secondary winding N1 exists between the output voltage of the first output circuit 132 and the output voltage of the second output circuit 133, the controller 1341 controls the switching element Q1 to be turned on, so that the switching circuit 13423 is turned on, so that the fourth resistor R4 is connected in parallel with the second resistor R2, so that the total resistance of the second resistor R2 and the fourth resistor R4 becomes smaller, so that the voltage of the sampling output end 13421A becomes smaller, and smaller than the reference voltage, so that the voltage between the negative electrode and the positive electrode of the controllable precision voltage stabilizing source K1 is turned off, so that the bus voltage of the output end of the first secondary winding N1 is raised, so that the sampling voltage of the sampling output end 13421A of the sampling circuit 13421 is raised, until the sampling voltage is dynamically balanced at the reference voltage again, so that the bus voltage of the output end of the first secondary winding N1 is dynamically stabilized at the bus voltage after being raised, so as to realize the voltage boosting of the output end of the first secondary winding N1, so that the output efficiency of the first output circuit 132 can be improved, and the output efficiency of the second output circuit 133 can be improved.
It is understood that the switching element Q1 includes at least one of a transistor (Bipolar Junction Transistor, BJT), a field-effect transistor (MOS), and an electromagnetic relay, and in the embodiment of the present application, the specific form of the switching element Q1 is not limited.
The switching element Q1 may be a field effect transistor, for example. Specifically, the switching element Q1 may be an NMOS (N-Metal-Oxide-Semiconductor) transistor, the base of the NMOS transistor is the controlled end of the switching element Q1, the drain of the NMOS transistor is the input end of the switching element Q1, the source of the NMOS transistor is the output end of the switching element Q1, when the controller 1341 sends a high-level signal to the base of the NMOS transistor, the drain and the source of the NMOS transistor are turned on, so that the switching circuit 13423 is turned on, so that the third resistor R3 is connected in parallel with the second resistor R2, and when the controller 1341 sends a low-level signal to the base of the NMOS transistor, the drain and the source of the NMOS transistor are turned off, so that the switching circuit 13423 is turned off.
Further, the switching circuit 13423 further includes a fifth resistor R5, a first end of the fifth resistor R5 is connected to the controlled end of the switching element Q1, a second end of the fifth resistor R5 is connected to the output end of the switching element Q1, and a voltage drop can be generated between the base and the source of the NMOS transistor by using the fifth resistor R5 when the controller 1341 sends a high level to the NMOS transistor, so as to facilitate the conduction of the NMOS transistor.
It is understood that the switching element Q1 may also be a PMOS (P-Metal-Oxide-Semiconductor) transistor, which is not described herein.
In the description of the present application, it should be understood that, if there is an orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", etc. based on the orientation or positional relationship shown in the drawings, it is merely for convenience of describing the present application and simplifying the description, and it is not intended to indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, so that the terms describing the positional relationship in the drawings are merely for exemplary illustration and are not to be construed as limiting the present application, and that the specific meaning of the terms described above should be understood by those of ordinary skill in the art according to the specific circumstances.
The foregoing description of the preferred embodiments of the application is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the application.
Claims (10)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202323239217.1U CN222191895U (en) | 2023-11-29 | 2023-11-29 | Charging circuit and charging device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202323239217.1U CN222191895U (en) | 2023-11-29 | 2023-11-29 | Charging circuit and charging device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN222191895U true CN222191895U (en) | 2024-12-17 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202323239217.1U Active CN222191895U (en) | 2023-11-29 | 2023-11-29 | Charging circuit and charging device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN222191895U (en) |
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- 2023-11-29 CN CN202323239217.1U patent/CN222191895U/en active Active
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