Charging circuit and charging equipment

Abstract

The utility model relates to a charging circuit and charging equipment, and the charging circuit comprises a voltage conversion circuit, the input end of the voltage conversion circuit is used for being coupled with an input power supply, and the voltage conversion circuit is used for converting the input voltage of the input power supply and outputting the converted input voltage; the first filter circuit comprises a first magnetic bead, a second magnetic bead and a first capacitor, the first magnetic bead is coupled with the first capacitor in parallel, the second magnetic bead is coupled with the first magnetic bead and the first capacitor which are connected in parallel in series, and the first filter circuit is arranged on the voltage conversion circuit. Due to the fact that noise is generated in the voltage conversion process of the voltage conversion circuit, the noise of the preset frequency can be effectively restrained through the first filter circuit composed of the first magnetic bead, the second magnetic bead and the first capacitor, electromagnetic interference in the charging circuit is reduced, and the possibility that the charging circuit breaks down is reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of charging technology, and in particular to a charging circuit and a charging device. Background Art

[0002] Currently, a charging device converts an input voltage of an input power source through a charging circuit to charge an electronic device. However, during the charging process of the electronic device, the charging circuit may generate electromagnetic interference (EMI), causing the charging circuit to malfunction. Utility Model Content

[0003] In order to overcome the problems existing in the related art, the present disclosure provides a charging circuit and a charging device.

[0004] According to a first aspect of the present disclosure, a charging circuit is provided, the charging circuit comprising:

[0005] A voltage conversion circuit, wherein the input end of the voltage conversion circuit is used to couple with an input power supply, and the voltage conversion circuit is used to convert the input voltage of the input power supply and then output it;

[0006] A first filter circuit, the first filter circuit includes a first magnetic bead, a second magnetic bead and a first capacitor, the first magnetic bead is coupled in parallel with the first capacitor, the second magnetic bead is coupled in series with the first magnetic bead and the first capacitor after the parallel connection, and the first filter circuit is arranged in the voltage conversion circuit.

[0007] In some embodiments of the present disclosure, the voltage conversion circuit includes:

[0008] A transformer, the transformer comprising a primary winding and a secondary winding;

[0009] a first conversion circuit, wherein an input end of the first conversion circuit is used to couple with the input power supply, an output end of the first conversion circuit is coupled with the primary winding, and the first conversion circuit is used to convert the input voltage and output it to the primary winding;

[0010] A second conversion circuit, wherein an input end of the second conversion circuit is coupled to the secondary winding, and the second conversion circuit is used for converting and outputting a voltage transmitted from the primary winding to the secondary winding.

[0011] In some embodiments of the present disclosure, the first filter circuit is coupled between the first conversion circuit and the primary winding; and / or the first filter circuit is coupled between the second conversion circuit and the secondary winding.

[0012] In some embodiments of the present disclosure, the first conversion circuit includes:

[0013] A rectifier and filter circuit, wherein an input end of the rectifier and filter circuit is used to couple with the input power supply, and a first output end of the rectifier and filter circuit is coupled with a first end of the primary winding;

[0014] A first switch unit, wherein a first end of the first switch unit is coupled to a first end of the first filter circuit, and a second end of the first switch unit is coupled to a second output end of the rectifier filter circuit and a first ground end;

[0015] Wherein, the second end of the first filter circuit is coupled to the second end of the primary winding.

[0016] In some embodiments of the present disclosure, the first conversion circuit further includes:

[0017] A second filter circuit, wherein the input end of the second filter circuit is used to couple with the input power supply, and the output end of the second filter circuit is coupled with the input end of the rectifier filter circuit.

[0018] In some embodiments of the present disclosure, the input end of the rectification and filtering circuit includes a first input end and a second input end; the second filtering circuit includes:

[0019] A common-mode inductor, wherein a first input end of the common-mode inductor is used to couple with a first end of the input power supply, a second input end of the common-mode inductor is used to couple with a second end of the input power supply, a first output end of the common-mode inductor is coupled with a first input end of the rectifier and filter circuit, and a second output end of the common-mode inductor is coupled with a second input end of the rectifier and filter circuit;

[0020] A differential mode capacitor, wherein a first end of the differential mode capacitor is coupled to a first output end of the common mode inductor, and a second end of the differential mode capacitor is coupled to a second output end of the common mode inductor.

[0021] In some embodiments of the present disclosure, the first conversion circuit further includes:

[0022] An absorption circuit is coupled in parallel with the primary winding.

[0023] In some embodiments of the present disclosure, the absorption circuit includes:

[0024] a second capacitor, a first end of the second capacitor being coupled to a first end of the primary winding;

[0025] A first resistor, the first resistor is coupled in parallel with the second capacitor;

[0026] a second resistor, a first end of the second resistor being coupled to a second end of the second capacitor;

[0027] a third resistor, the third resistor being coupled in parallel with the second resistor;

[0028] A unidirectional conduction unit, wherein the first end of the unidirectional conduction unit is coupled to the second end of the second resistor, the second end of the unidirectional conduction unit is coupled to the second end of the primary winding, and the unidirectional conduction unit is used to allow current to flow unidirectionally from the primary winding to the second resistor and the third resistor.

[0029] In some embodiments of the present disclosure, the transformer further includes:

[0030] A shielding winding, one end of which is used to be coupled to the first grounding end.

[0031] In some embodiments of the present disclosure, the second conversion circuit includes:

[0032] a second switch unit, wherein a first end of the second switch unit is coupled to a first end of the secondary winding;

[0033] A third capacitor, wherein the first end of the third capacitor is coupled to the second end of the second switch unit, the second end of the third capacitor is coupled to the second end of the secondary winding and the second ground end, and the first end and the second end of the third capacitor are both used to couple to the interface.

[0034] In some embodiments of the present disclosure, the first switch unit includes a first transistor, a drain of the first transistor is coupled to a first end of the first filter circuit, and a source of the first transistor is coupled to a second output end of the rectifier filter circuit and the first ground end;

[0035] The second switch unit comprises a second transistor, a drain of the second transistor is coupled to the first end of the third capacitor, and a source of the second transistor is coupled to the first end of the secondary winding;

[0036] Wherein, the first end of the primary winding and the second end of the secondary winding are the same-named ends.

[0037] According to a second aspect of the present disclosure, a charging device is provided, comprising the charging circuit as described above.

[0038] The technical solution provided by the embodiments of the present disclosure may have the following beneficial effects:

[0039] The charging circuit includes a voltage conversion circuit and a first filtering circuit. The first filtering circuit includes a first magnetic bead, a second magnetic bead and a first capacitor. The first magnetic bead is coupled in parallel with the first capacitor, and the second magnetic bead is coupled in series with the first magnetic bead and the first capacitor after the parallel connection. The first filtering circuit is used to suppress the noise of a preset frequency in the voltage conversion circuit. Since the voltage conversion circuit generates noise during the voltage conversion process, the first filtering circuit composed of the first magnetic bead, the second magnetic bead and the first capacitor can effectively suppress the noise of the preset frequency, thereby reducing the electromagnetic interference in the charging circuit to reduce the possibility of failure of the charging circuit. In addition, since the magnetic beads exhibit resistance characteristics at high frequencies and can consume noise in the form of heat energy, and exhibit inductance characteristics at low frequencies and do not consume energy, the power consumption of the charging circuit is reduced.

[0040] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings herein are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present utility model, and together with the description, are used to explain the principles of the present utility model.

[0042] Figure 1 is a structural schematic diagram of a charging circuit provided by an exemplary embodiment of the present disclosure;

[0043] Figure 2 is a structural schematic diagram of a charging circuit provided by another exemplary embodiment of the present disclosure;

[0044] Figure 3-1 is a structural schematic diagram of a charging circuit provided by another exemplary embodiment of the present disclosure;

[0045] Figure 3-2 is a structural schematic diagram of a charging circuit provided by another exemplary embodiment of the present disclosure;

[0046] Figure 3-3 is a structural schematic diagram of a charging circuit provided by another exemplary embodiment of the present disclosure;

[0047] Figure 4 is a structural schematic diagram of a charging circuit provided by another exemplary embodiment of the present disclosure;

[0048] Figure 5 is a structural schematic diagram of a charging circuit provided by another exemplary embodiment of the present disclosure;

[0049] Figure 6 is a structural schematic diagram of a charging circuit provided by another exemplary embodiment of the present disclosure;

[0050] Figure 7is a structural schematic diagram of a charging circuit provided by another exemplary embodiment of the present disclosure;

[0051] Figure 8-1 is a curve diagram of radiation emission noise and frequency provided by an exemplary embodiment of the present disclosure;

[0052] Figure 8-2 is a curve diagram of radiation emission noise and frequency provided by another exemplary embodiment of the present disclosure;

[0053] Fig. 9 is a system block diagram of an electronic device provided by an exemplary embodiment of the present disclosure.

[0054] In the figure:

[0055] 10-voltage conversion circuit; 11-first conversion circuit; 111-rectifier filter circuit; 112-second filter circuit; 113-absorption circuit; 12-second conversion circuit; 20-first filter circuit; 30-interface; 400-electronic device; 402-processing component; 404-memory; 406-power supply component; 408-multimedia component; 410-audio component; 412-input and output interface; 414-sensor component; 416-communication component; 420-processor; AC-input power supply; L1-first magnetic bead; L2-second magnetic bead; C1-first electric Capacitor; C2-second capacitor; C3-third capacitor; C4-fourth capacitor; R1-first resistor; R2-second resistor; R3-third resistor; T-transformer; N1-primary winding; N2-secondary winding; N3-shielding winding; GND1-first ground terminal; GND2-second ground terminal; T1-first transistor; T2-second transistor; D1-first diode; D2-second diode; D3-third diode; D4-fourth diode; D5-fifth diode; D6-sixth diode; D7-seventh diode; Lcm-common mode inductor; Cd-differential mode capacitor. DETAILED DESCRIPTION

[0056] Here, exemplary embodiments will be described in detail, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the utility model. On the contrary, they are only examples of devices and methods consistent with some aspects of the utility model as detailed in the attached claims. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0057] At present, charging devices convert the input voltage of the input power supply through the charging circuit to charge the electronic device. The transformer in the charging circuit can adjust the voltage output to the electronic device on the one hand, and isolate the input power supply and the electronic device on the other hand to prevent the electronic device from being affected. However, in the process of charging the electronic device, the frequent switching of the transistor in the charging circuit and the operation of the transformer will generate electromagnetic interference, causing the charging circuit to malfunction.

[0058] In the related art, a circuit structure for reducing electromagnetic interference is provided, which includes a common-mode inductor and a differential-mode capacitor, which are arranged between the input power supply and the charging circuit. The common-mode inductor is used to suppress the common-mode interference, and the differential-mode capacitor is used to suppress the differential-mode interference, thereby reducing the electromagnetic interference in the charging circuit. However, it is difficult to suppress the radiated emission (RE) noise in the charging circuit with this circuit structure, and the charging circuit may still fail.

[0059] Based on this, the present disclosure provides a charging circuit. A first filter circuit composed of a first magnetic bead, a second magnetic bead and a first capacitor suppresses noise of a preset frequency in a voltage conversion circuit, and can suppress radiated emission noise, thereby reducing electromagnetic interference in the charging circuit and reducing the possibility of failure of the charging circuit.

[0060] An exemplary embodiment of the present disclosure provides a charging circuit, such as Figure 1 As shown, the charging circuit includes a voltage conversion circuit 10 and a first filtering circuit 20. The input end of the voltage conversion circuit 10 is used to couple with the input power supply AC, and the voltage conversion circuit 10 is used to convert the input voltage of the input power supply AC and output it. The first filtering circuit 20 includes a first magnetic bead L1, a second magnetic bead L2 and a first capacitor C1. The first magnetic bead L1 is coupled in parallel with the first capacitor C1, and the second magnetic bead L2 is coupled in series with the first magnetic bead L1 and the first capacitor C1 after being connected in parallel. The first filtering circuit 20 is arranged in the voltage conversion circuit 10, and the first filtering circuit 20 is used to suppress the noise of a preset frequency in the voltage conversion circuit 10.

[0061] In this embodiment, the charging circuit includes a voltage conversion circuit and a first filtering circuit. The first filtering circuit includes a first magnetic bead, a second magnetic bead and a first capacitor. The first magnetic bead is coupled in parallel with the first capacitor, and the second magnetic bead is coupled in series with the first magnetic bead and the first capacitor after the parallel connection. The first filtering circuit is used to suppress the noise of a preset frequency in the voltage conversion circuit. Since the voltage conversion circuit generates noise during the voltage conversion process, the first filtering circuit composed of the first magnetic bead, the second magnetic bead and the first capacitor can effectively suppress the noise of the preset frequency, thereby reducing the electromagnetic interference in the charging circuit to reduce the possibility of failure of the charging circuit. In addition, since the magnetic beads exhibit resistance characteristics at high frequencies and can consume noise in the form of heat energy, and exhibit inductance characteristics at low frequencies and do not consume energy, the power consumption of the charging circuit is reduced.

[0062] Exemplarily, the input power source AC may be an alternating current power source, for example, an industrial frequency alternating current power source. The first magnetic bead L1 and the second magnetic bead L2 may be ferrite magnetic beads. The specifications of the first magnetic bead L1 and the second magnetic bead L2 may be the same or different.

[0063] It is understandable that due to the special properties of the magnetic beads, for the high-frequency noise in the voltage conversion circuit 10, the magnetic beads show resistance characteristics. For the low-frequency noise in the voltage conversion circuit 10, the magnetic beads show inductance characteristics. Since the radiated emission noise at high frequencies is strong, the magnetic beads can consume the noise in the form of heat energy, thereby reducing electromagnetic interference. Since the radiated emission noise at low frequencies will be enhanced after the first magnetic bead L1 is added to the voltage conversion circuit 10, the radiated emission noise at low frequencies can be suppressed by connecting the first capacitor C1 in parallel, thereby reducing electromagnetic interference. After the first capacitor C1 is added, the radiated emission noise at high frequencies will be enhanced, and the radiated emission noise at high frequencies can be suppressed by connecting the second magnetic bead L2 in series, thereby reducing electromagnetic interference. Among them, the frequency of the noise suppressed by the first magnetic bead L1 and the second magnetic bead L2 can be 150MHz~1000MHz, and the frequency of the noise suppressed by the first capacitor C1 can be 30MHz~100MHz. That is, the first filter circuit 20 can be a bandpass filter circuit, and the preset frequency can be part or all of the frequencies in 30MHz~100MHz and 150MHz~1000MHz.

[0064] In one embodiment, if Figure 2As shown, the voltage conversion circuit includes a transformer T, a first conversion circuit 11 and a second conversion circuit 12. The transformer T includes a primary winding N1 and a secondary winding N2. The input end of the first conversion circuit 11 is used to couple with the input power supply AC, the output end of the first conversion circuit 11 is coupled with the primary winding N1, and the first conversion circuit 11 is used to convert the input voltage and output it to the primary winding N1. The input end of the second conversion circuit 12 is coupled with the secondary winding N2, and the second conversion circuit 12 is used to convert the voltage transmitted from the primary winding N1 to the secondary winding N2 and output it.

[0065] In this embodiment, the first conversion circuit and the second conversion circuit are coupled by a transformer, so that the voltage converted to the primary winding is changed according to a certain ratio and then output from the secondary winding to the second conversion circuit, thereby providing a suitable charging voltage to improve the performance of the charging circuit. At the same time, since the transformer can isolate the first conversion circuit from the second conversion circuit, the second conversion circuit is prevented from being affected by the first conversion circuit, thereby improving the reliability of the charging circuit.

[0066] In one embodiment, if Figure 3-1 As shown, the first filter circuit 20 is coupled between the first conversion circuit 11 and the primary winding N1 .

[0067] In this embodiment, since the first conversion circuit generates radiation emission noise when performing voltage conversion and affects the charging circuit, the radiation emission noise generated by the first conversion circuit can be suppressed by the first filter circuit, thereby reducing the electromagnetic interference in the charging circuit to reduce the possibility of failure of the charging circuit. In addition, since the voltage of the primary winding is higher than the voltage of the secondary winding, the radiation emission noise in the first conversion circuit is stronger than the radiation emission noise in the second conversion circuit. By coupling the first filter circuit between the first conversion circuit and the primary winding, the effect of suppressing the radiation emission noise can be improved as much as possible while occupying the same volume of the charging circuit, thereby improving the reliability of the charging circuit. In addition, since the number of the first filter circuits is small, the volume of the charging circuit can be reduced, thereby improving the portability of the charging device.

[0068] In one embodiment, if Figure 3-2 As shown, the first filter circuit 20 is coupled between the second conversion circuit 12 and the secondary winding N2 .

[0069] In this embodiment, since the second conversion circuit generates radiated emission noise when performing voltage conversion and affects the charging circuit, the radiated emission noise generated by the second conversion circuit can be suppressed by the first filtering circuit, thereby reducing electromagnetic interference in the charging circuit to reduce the possibility of malfunction of the charging circuit. In addition, since the number of first filtering circuits is small, the volume of the charging circuit can be reduced, thereby improving the portability of the charging device.

[0070] In one embodiment, if Figure 3-3 As shown, there are two first filter circuits 20. One first filter circuit 20 is coupled between the first conversion circuit 11 and the primary winding N1, and another first filter circuit 20 is coupled between the second conversion circuit 12 and the secondary winding N2.

[0071] In this embodiment, since the first conversion circuit and the second conversion circuit generate radiation emission noise when performing voltage conversion and affect the charging circuit, the radiation emission noise generated by the first conversion circuit and the second conversion circuit can be suppressed by the first filtering circuit, thereby reducing electromagnetic interference in the charging circuit and reducing the possibility of malfunction of the charging circuit.

[0072] In one embodiment, if Figure 4 As shown, the first conversion circuit 11 includes a rectifier filter circuit 111 and a first switch unit. The input end of the rectifier filter circuit 111 is used to couple with the input power supply AC, and the first output end of the rectifier filter circuit 111 is coupled with the first end of the primary winding N1. The first end of the first switch unit is coupled with the first end of the first filter circuit 20, and the second end of the first switch unit is coupled with the second output end of the rectifier filter circuit 111 and the first ground terminal GND1. Among them, the second end of the first filter circuit 20 is coupled with the second end of the primary winding N1.

[0073] In this embodiment, the input voltage is converted into a DC voltage by a rectifier filter circuit, and the DC voltage is converted into a high-frequency AC voltage by using the high-frequency switching of the first switch unit, thereby reducing the size of the transformer. In addition, since the high-frequency switching of the first switch unit and the transmission of electric energy through the transformer will generate strong radiation emission noise, by arranging the first filter circuit between the primary winding and the first switch unit, the effect of the first filter circuit in suppressing the radiation emission noise can be improved to reduce the possibility of failure of the charging circuit.

[0074] Exemplarily, the first end of the first magnetic bead L1 is coupled to the first end of the first capacitor C1, and the first end of the second magnetic bead L2 is coupled to the second end of the first magnetic bead L1 and the second end of the first capacitor C1. The first end of the first filter circuit 20 may be the first end of the first magnetic bead L1 and the first end of the first capacitor C1, or the second end of the second magnetic bead L2. The second end of the first filter circuit 20 may be the second end of the second magnetic bead L2, or the first end of the first magnetic bead L1 and the first end of the first capacitor C1.

[0075] Exemplarily, the first conversion circuit 11 further includes a first diode D1 , an anode of the first diode D1 is coupled to the second end of the first switch unit, and a cathode of the first diode D1 is coupled to the first end of the first switch unit.

[0076] Exemplarily, in addition to being coupled between the primary winding N1 and the first switch unit, the first filter circuit 20 can also be coupled between the first output end of the rectifier filter circuit 111 and the first end of the primary winding N1, and can also be coupled between the second end of the first switch unit and the second output end of the rectifier filter circuit 111.

[0077] Exemplarily, the rectifier and filter circuit 111 may include a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5 and a fourth capacitor C4. The anode of the second diode D2 is coupled to the first end of the input power supply AC and the cathode of the fourth diode D4, and the cathode of the second diode D2 is coupled to the cathode of the third diode D3, the first end of the fourth capacitor C4 and the first end of the primary winding N1. The anode of the third diode D3 is coupled to the second end of the input power supply AC and the cathode of the fifth diode D5. The anode of the fourth diode D4 is coupled to the anode of the fifth diode D5, the second end of the fourth capacitor C4, the second end of the first switch unit and the first ground terminal GND1.

[0078] In one embodiment, if Figure 5 As shown, the first conversion circuit 11 further includes a second filter circuit 112. The input end of the second filter circuit 112 is used to couple with the input power source AC, and the output end of the second filter circuit 112 is coupled with the input end of the rectifier filter circuit 111.

[0079] In this embodiment, the electromagnetic interference of the input power supply can be suppressed by the second filter circuit, thereby further reducing the electromagnetic interference in the charging circuit, thereby reducing the possibility of failure of the charging circuit.

[0080] In one embodiment, the input end of the rectifier and filter circuit 111 includes a first input end and a second input end. The second filter circuit 112 includes a common mode inductor Lcm and a differential mode capacitor Cd. The first input end of the common mode inductor Lcm is used to couple with the first end of the input power supply AC, the second input end of the common mode inductor Lcm is used to couple with the second end of the input power supply AC, the first output end of the common mode inductor Lcm is coupled with the first input end of the rectifier and filter circuit 111, and the second output end of the common mode inductor Lcm is coupled with the second input end of the rectifier and filter circuit 111. The first end of the differential mode capacitor Cd is coupled with the first output end of the common mode inductor Lcm, and the second end of the differential mode capacitor Cd is coupled with the second output end of the common mode inductor Lcm.

[0081] In this embodiment, the common-mode interference and differential-mode interference of the input power supply are filtered out respectively by the common-mode inductor and the differential-mode capacitor, thereby further reducing the electromagnetic interference in the charging circuit, thereby reducing the possibility of failure of the charging circuit.

[0082] Exemplarily, the first input end of the rectifying and filtering circuit 111 may be the anode of the second diode D2 and the cathode of the fourth diode D4, or the anode of the third diode D3 and the cathode of the fifth diode D5. The second input end of the rectifying and filtering circuit 111 may be the anode of the third diode D3 and the cathode of the fifth diode D5, or the anode of the second diode D2 and the cathode of the fourth diode D4.

[0083] In one embodiment, the first conversion circuit 11 further includes an absorption circuit 113. The absorption circuit 113 is coupled in parallel with the primary winding N1.

[0084] In this embodiment, since a voltage spike will appear in the primary winding when the first switch unit is turned on and off, an excessively high voltage spike may cause the first switch unit to be overstressed and damaged. The voltage spike is suppressed by the absorption circuit connected in parallel with the primary winding to prevent the first switch unit from being damaged, thereby improving the reliability of the charging circuit.

[0085] In one embodiment, if Figure 6 As shown, the absorption circuit 113 includes a second capacitor C2, a first resistor R1, a second resistor R2, a third resistor R3 and a unidirectional conduction unit. The first end of the second capacitor C2 is coupled to the first end of the primary winding N1. The first resistor R1 is coupled in parallel with the second capacitor C2. The first end of the second resistor R2 is coupled to the second end of the second capacitor C2. The third resistor R3 is coupled in parallel with the second resistor R2. The first end of the unidirectional conduction unit is coupled to the second end of the second resistor R2, the second end of the unidirectional conduction unit is coupled to the second end of the primary winding N1, and the unidirectional conduction unit is used to make the current flow from the primary winding N1 to the second resistor R2 and the third resistor R3 in one direction.

[0086] In this embodiment, the first resistor, the second resistor, the third resistor, the second capacitor and the unidirectional conductive unit constitute an RCD absorption circuit to suppress voltage spikes and prevent the first switch unit from being damaged, thereby improving the reliability of the charging circuit.

[0087] Exemplarily, the unidirectional conducting unit may include a sixth diode D6. A cathode of the sixth diode D6 is coupled to the second end of the second resistor R2, and an anode of the sixth diode D6 is coupled to the second end of the primary winding N1.

[0088] For example, in addition to suppressing the voltage spike by using an RCD absorption circuit, the voltage spike may also be suppressed by using an RC absorption circuit, an LC absorption circuit, etc.

[0089] In one embodiment, if Figure 7 As shown, the transformer further includes a shielding winding N3. One end of the shielding winding N3 is used to couple to the first ground terminal GND1.

[0090] In this embodiment, by grounding one end of the shielding winding, electromagnetic interference in the charging circuit can be reduced, thereby reducing the possibility of malfunction of the charging circuit.

[0091] In one embodiment, if Figures 4 to 7 As shown, the second conversion circuit 12 includes a second switch unit and a third capacitor C3. The first end of the second switch unit is coupled to the first end of the secondary winding N2. The first end of the third capacitor C3 is coupled to the second end of the second switch unit, the second end of the third capacitor C3 is coupled to the second end of the secondary winding N2 and the second ground terminal GND2, and the first end and the second end of the third capacitor C3 are both used to couple with the interface 30.

[0092] In this embodiment, the high-frequency AC voltage of the secondary winding is converted into a DC voltage and output to the interface through the second switch unit, so that the function of synchronous rectification can be realized, thereby reducing the power consumption of the charging circuit.

[0093] In one embodiment, if Figures 4 to 7 As shown, the first switch unit includes a first transistor T1. The drain of the first transistor T1 is coupled to the first end of the first filter circuit 20, and the source of the first transistor T1 is coupled to the second output end of the rectifier filter circuit 111 and the first ground terminal GND1. The second switch unit includes a second transistor T2. The drain of the second transistor T2 is coupled to the first end of the third capacitor C3, and the source of the second transistor T2 is coupled to the first end of the secondary winding N2. The first end of the primary winding N1 and the second end of the secondary winding N2 are the same end.

[0094] In this embodiment, since the voltage conversion circuit is a flyback circuit, the size of the transformer is small and the withstand voltage required by the first transistor is low, thereby reducing the size and cost of the charging device.

[0095] Exemplarily, the second conversion circuit 12 further includes a seventh diode D7. An anode of the seventh diode D7 is coupled to the first end of the second switch unit, and a cathode of the seventh diode D7 is coupled to the second end of the second switch unit.

[0096] Exemplarily, the first diode D1 may be a body diode of the first transistor T1 , and the seventh diode D7 may be a body diode of the second transistor T2 .

[0097] Exemplarily, the first filtering circuit 20 may be coupled between a first end of the second switch unit and a first end of the secondary winding N2 .

[0098] Exemplarily, the voltage conversion circuit 10 can be a flyback circuit as well as a forward circuit, a half-bridge circuit, a full-bridge circuit, or other circuits with a transformer; it can also be a boost circuit (Boost circuit), a buck circuit (Buck circuit), a buck-boost circuit (Buck-Boost circuit), or other circuits without a transformer.

[0099] For example, Figure 8-1 and Figure 8-2 As shown in the figure, in the charging circuit, the radiated emission noise at different frequencies is tested. The horizontal axis represents the frequency in MHz, and the vertical axis represents the gain of the radiated noise in dB. S1 is the standard line, and S2 is the 6dB margin line. Figure 8-1 As shown, when the charging circuit does not include the first filter circuit 20, when the frequency is around 200 MHz, the gain of the radiated emission noise is between the standard line and the margin line, and the electromagnetic interference does not meet the requirements and may cause the charging circuit to malfunction. Figure 8-2 As shown, when the charging circuit includes the first filter circuit 20, the gain of the radiated emission noise at each frequency is less than the margin line, and the electromagnetic interference meets the requirements and will not cause the charging circuit to malfunction.

[0100] In an exemplary embodiment, a charging device is provided. The charging device includes the charging circuit as described above.

[0101] In an exemplary embodiment, an electronic device is provided, and the electronic device is, for example, a mobile phone, a laptop computer, a tablet computer, a wearable device, etc. The electronic device includes an interface 30 , and a charging device charges the electronic device through the interface 30 .

[0102] refer to Fig. 9 As shown, electronic device 400 may include one or more of the following components: a processing component 402 , a memory 404 , a power component 406 , a multimedia component 408 , an audio component 410 , an input / output (I / O) interface 412 , a sensor component 414 , and a communication component 416 .

[0103] The processing component 402 generally controls the overall operation of the electronic device 400, such as operations associated with display, phone calls, data communications, camera operations, and recording operations. The processing component 402 may include one or more processors 420 to execute instructions to complete all or part of the steps of the above-mentioned method. In addition, the processing component 402 may include one or more modules to facilitate the interaction between the processing component 402 and other components. For example, the processing component 402 may include a multimedia module to facilitate the interaction between the multimedia component 408 and the processing component 402.

[0104] The memory 404 is configured to store various types of data to support operations on the electronic device 400. Examples of such data include instructions for any application or method operating on the electronic device 400, contact data, phone book data, messages, pictures, videos, etc. The memory 404 can be implemented by any type of volatile or non-volatile storage terminal or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0105] The power supply component 406 provides power to the various components of the electronic device 400. The power supply component 406 may include a power management system, one or more power supplies, and other components associated with generating, managing, and distributing power to the electronic device 400.

[0106] The multimedia component 408 includes a screen that provides an output interface between the electronic device 400 and the user. In some embodiments, the screen may include a liquid crystal display (LCD) and a touch panel (TP). If the screen includes a touch panel, the screen may be implemented as a touch screen to receive input signals from the user. The touch panel includes one or more touch sensors to sense touch, slide, and gestures on the touch panel. The touch sensor may not only sense the boundaries of the touch or slide action, but also detect the duration and pressure associated with the touch or slide operation. In some embodiments, the multimedia component 408 includes a front camera module and / or a rear camera module. When the electronic device 400 is in an operating mode, such as a shooting mode or a video mode, the front camera module and / or the rear camera module may receive external multimedia data. Each front camera module and the rear camera module may be a fixed optical lens system or have a focal length and optical zoom capability.

[0107] The audio component 410 is configured to output and / or input audio signals. For example, the audio component 410 includes a microphone (MIC), and when the electronic device 400 is in an operating mode, such as a call mode, a recording mode, and a voice recognition mode, the microphone is configured to receive an external audio signal. The received audio signal can be further stored in the memory 404 or sent via the communication component 416. In some embodiments, the audio component 410 also includes a speaker for outputting audio signals.

[0108] I / O interface 412 provides an interface between processing component 402 and peripheral interface modules, such as keyboards, click wheels, buttons, etc. These buttons may include but are not limited to: a home button, a volume button, a start button, and a lock button.

[0109] The sensor assembly 414 includes one or more sensors for providing various aspects of status assessment for the electronic device 400. For example, the sensor assembly 414 can detect the open / closed state of the electronic device 400, the relative positioning of components, such as the display and keypad of the electronic device 400, and the sensor assembly 414 can also detect the position change of the electronic device 400 or a component of the electronic device 400, the presence or absence of user contact with the electronic device 400, the orientation or acceleration / deceleration of the electronic device 400, and the temperature change of the electronic device 400. The sensor assembly 414 may include a proximity sensor configured to detect the presence of nearby objects without any physical contact. The sensor assembly 414 may also include an optical sensor, such as a CMOS or CCD image sensor, for use in imaging applications. In some embodiments, the sensor assembly 414 may also include an accelerometer, a gyroscope sensor, a magnetic sensor, a pressure sensor, or a temperature sensor.

[0110] The communication component 416 is configured to facilitate wired or wireless communication between the electronic device 400 and other terminals. The electronic device 400 can access a wireless network based on a communication standard, such as WiFi, 2G, 3G, 4G, 5G, or a combination thereof. In an exemplary embodiment, the communication component 416 receives a broadcast signal or broadcast-related information from an external broadcast management system via a broadcast channel. In an exemplary embodiment, the communication component 416 also includes a near field communication (NFC) module to facilitate short-range communication. For example, the NFC module can be implemented based on radio frequency identification (RFID) technology, infrared data association (IrDA) technology, ultra-wideband (UWB) technology, Bluetooth (BT) technology and other technologies.

[0111] In an exemplary embodiment, the electronic device 400 may be implemented by one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing terminals (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components.

[0112] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0113] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0114] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the utility model disclosed herein. The present disclosure is intended to cover any variations, uses or adaptations of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and examples are to be regarded as exemplary only, and the true scope and spirit of the present disclosure are indicated by the claims.

[0115] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A charging circuit, characterized in that: The charging circuit comprises: A voltage conversion circuit, wherein the input end of the voltage conversion circuit is used to couple with an input power supply, and the voltage conversion circuit is used to convert the input voltage of the input power supply and then output it; A first filter circuit, the first filter circuit includes a first magnetic bead, a second magnetic bead and a first capacitor, the first magnetic bead is coupled in parallel with the first capacitor, the second magnetic bead is coupled in series with the first magnetic bead and the first capacitor after the parallel connection, and the first filter circuit is arranged in the voltage conversion circuit.

2. The charging circuit according to claim 1, characterized in that: The voltage conversion circuit comprises: A transformer, the transformer comprising a primary winding and a secondary winding; a first conversion circuit, wherein an input end of the first conversion circuit is used to couple with the input power supply, an output end of the first conversion circuit is coupled with the primary winding, and the first conversion circuit is used to convert the input voltage and output it to the primary winding; A second conversion circuit, wherein an input end of the second conversion circuit is coupled to the secondary winding, and the second conversion circuit is used for converting and outputting a voltage transmitted from the primary winding to the secondary winding.

3. The charging circuit according to claim 2, characterized in that: The first filter circuit is coupled between the first conversion circuit and the primary winding; and / or the first filter circuit is coupled between the second conversion circuit and the secondary winding.

4. The charging circuit according to claim 3, characterized in that: The first conversion circuit comprises: A rectifier and filter circuit, wherein an input end of the rectifier and filter circuit is used to couple with the input power supply, and a first output end of the rectifier and filter circuit is coupled with a first end of the primary winding; A first switch unit, wherein a first end of the first switch unit is coupled to a first end of the first filter circuit, and a second end of the first switch unit is coupled to a second output end of the rectifier filter circuit and a first ground end; Wherein, the second end of the first filter circuit is coupled to the second end of the primary winding.

5. The charging circuit according to claim 4, characterized in that: The first conversion circuit further includes: A second filter circuit, wherein the input end of the second filter circuit is used to couple with the input power supply, and the output end of the second filter circuit is coupled with the input end of the rectifier filter circuit.

6. The charging circuit according to claim 5, characterized in that: The input end of the rectifying and filtering circuit includes a first input end and a second input end; the second filtering circuit includes: A common-mode inductor, wherein a first input end of the common-mode inductor is used to couple with a first end of the input power supply, a second input end of the common-mode inductor is used to couple with a second end of the input power supply, a first output end of the common-mode inductor is coupled with a first input end of the rectifier and filter circuit, and a second output end of the common-mode inductor is coupled with a second input end of the rectifier and filter circuit; A differential mode capacitor, wherein a first end of the differential mode capacitor is coupled to a first output end of the common mode inductor, and a second end of the differential mode capacitor is coupled to a second output end of the common mode inductor.

7. The charging circuit according to claim 4, characterized in that: The first conversion circuit further includes: An absorption circuit is coupled in parallel with the primary winding.

8. The charging circuit according to claim 7, characterized in that: The absorption circuit comprises: a second capacitor, a first end of the second capacitor being coupled to a first end of the primary winding; A first resistor, the first resistor is coupled in parallel with the second capacitor; a second resistor, a first end of the second resistor being coupled to a second end of the second capacitor; a third resistor, the third resistor being coupled in parallel with the second resistor; A unidirectional conduction unit, wherein the first end of the unidirectional conduction unit is coupled to the second end of the second resistor, the second end of the unidirectional conduction unit is coupled to the second end of the primary winding, and the unidirectional conduction unit is used to allow current to flow unidirectionally from the primary winding to the second resistor and the third resistor.

9. The charging circuit according to claim 4, characterized in that: The transformer also includes: A shielding winding, one end of which is used to be coupled to the first ground end.

10. The charging circuit according to any one of claims 4 to 9, characterized in that: The second conversion circuit comprises: a second switch unit, wherein a first end of the second switch unit is coupled to a first end of the secondary winding; A third capacitor, wherein the first end of the third capacitor is coupled to the second end of the second switch unit, the second end of the third capacitor is coupled to the second end of the secondary winding and the second ground end, and the first end and the second end of the third capacitor are both used to couple to the interface.

11. The charging circuit according to claim 10, characterized in that: The first switch unit includes a first transistor, a drain of the first transistor is coupled to the first end of the first filter circuit, and a source of the first transistor is coupled to the second output end of the rectifier filter circuit and the first ground end; The second switch unit comprises a second transistor, a drain of the second transistor is coupled to the first end of the third capacitor, and a source of the second transistor is coupled to the first end of the secondary winding; Wherein, the first end of the primary winding and the second end of the secondary winding are the same-named ends.

12. A charging device, characterized in that: The charging device comprises the charging circuit according to any one of claims 1 to 11.

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