Power supply circuit, voltage conversion circuit, charging equipment and electronic equipment

Abstract

The utility model relates to a power supply circuit, a voltage conversion circuit, charging equipment and electronic equipment. The power supply circuit comprises a first switch unit, the first end of which is used for being coupled with an alternating current power supply, and the first switch unit is used for rectifying alternating current voltage output by the alternating current power supply to obtain direct current voltage; the first end of the first conversion circuit is used for being coupled with an alternating current power supply, the second end of the first conversion circuit is used for being coupled with the second end of the first switch unit, the third end of the first conversion circuit is coupled with the control end of the first switch unit, and the first conversion circuit is used for controlling on and off of the first switch unit; the first end of the voltage stabilizing circuit is coupled with an alternating current power supply, the second end of the voltage stabilizing circuit is coupled with the second end of the first switch unit, the third end of the voltage stabilizing circuit is coupled with a control circuit, and the voltage stabilizing circuit is used for stabilizing the direct current voltage to supply power to the control circuit. As the conduction power consumption of the first switch unit is low, the power consumption of the power supply circuit is reduced by rectifying through the first switch unit.

Description

Technical Field

[0001] The present disclosure relates to the field of power supply technology, and in particular to a power supply circuit, a voltage conversion circuit, a charging device and an electronic device. Background Art

[0002] At present, the power supply circuit rectifies the AC voltage of the AC power source and then supplies power to the control circuit, so that the control circuit is in operation to control the voltage output to the load. However, in the process of rectifying the AC voltage by the power supply circuit, the power supply circuit has a large power consumption, resulting in low efficiency of the power supply circuit. Utility Model Content

[0003] In order to overcome the problems existing in the related art, the present disclosure provides a power supply circuit, a voltage conversion circuit, a charging device and an electronic device.

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

[0005] a first switch unit, wherein a first end of the first switch unit is used to couple with an AC power source, and the first switch unit is used to rectify an AC voltage output by the AC power source to obtain a DC voltage;

[0006] a first conversion circuit, wherein a first end of the first conversion circuit is used to couple with the AC power supply, a second end of the first conversion circuit is coupled with a second end of the first switch unit, a third end of the first conversion circuit is coupled with a control end of the first switch unit, and the first conversion circuit is used to control the conduction and disconnection of the first switch unit;

[0007] A voltage stabilizing circuit, wherein the first end of the voltage stabilizing circuit is used to couple with the AC power supply, the second end of the voltage stabilizing circuit is coupled with the second end of the first switch unit, the third end of the voltage stabilizing circuit is used to couple with the control circuit, and the voltage stabilizing circuit is used to stabilize the DC voltage to power the control circuit.

[0008] In some embodiments of the present disclosure, the first switch unit includes:

[0009] A first transistor, wherein a first end of the first transistor is used to couple with a first end of the AC power supply, a second end of the first transistor is coupled with a second end of the voltage stabilizing circuit, and a control end of the first transistor is coupled with a third end of the first conversion circuit.

[0010] In some embodiments of the present disclosure, the first conversion circuit includes:

[0011] A voltage divider circuit, wherein the first end of the voltage divider circuit is used to couple with the second end of the AC power supply, the second end of the voltage divider circuit is coupled with the second end of the first switch unit, and the third end of the voltage divider circuit is coupled with the control end of the first switch unit.

[0012] In some embodiments of the present disclosure, the voltage divider circuit includes:

[0013] a first resistor, wherein a first end of the first resistor is used to be coupled to a second end of the AC power source, and a second end of the first resistor is coupled to a control end of the first switch unit;

[0014] a second resistor, wherein a first end of the second resistor is coupled to a second end of the first resistor, and a second end of the second resistor is coupled to a second end of the first switch unit; or

[0015] A variable resistor, wherein the first fixed end of the variable resistor is used to couple with the second end of the AC power supply, the second fixed end of the variable resistor is coupled with the second end of the first switch unit, and the variable end of the variable resistor is coupled with the control end of the first switch unit.

[0016] In some embodiments of the present disclosure, the voltage stabilizing circuit includes:

[0017] A first capacitor, wherein a first end of the first capacitor is used to couple to a second end of the AC power supply and a first end of the control circuit, and a second end of the first capacitor is coupled to a second end of the first switch unit and a second end of the control circuit.

[0018] In some embodiments of the present disclosure, the voltage stabilizing circuit further includes:

[0019] an emitter follower circuit, wherein a first end of the emitter follower circuit is coupled to a first end of the first capacitor, and a second end of the emitter follower circuit is used to couple to a first end of the control circuit;

[0020] A first voltage regulator tube, wherein a cathode of the first voltage regulator tube is coupled to the third end of the emitter follower circuit, and an anode of the first voltage regulator tube is used to couple to the second end of the control circuit.

[0021] In some embodiments of the present disclosure, the emitter follower circuit includes:

[0022] A transistor, wherein the base of the transistor is coupled to the cathode of the first voltage regulator tube, the collector of the transistor is coupled to the first end of the first capacitor, and the emitter of the transistor is used to couple to the first end of the control circuit;

[0023] A third resistor, wherein a first end of the third resistor is coupled to the collector of the transistor, and a second end of the third resistor is coupled to the base of the transistor.

[0024] In some embodiments of the present disclosure, the voltage stabilizing circuit further includes:

[0025] A second capacitor, wherein a first end of the second capacitor is coupled to a second end of the emitter follower circuit, and a second end of the second capacitor is coupled to an anode of the first voltage regulator tube.

[0026] In some embodiments of the present disclosure, the power supply circuit further includes:

[0027] A current limiting circuit is coupled between the first conversion circuit and the voltage stabilizing circuit.

[0028] In some embodiments of the present disclosure, the current limiting circuit includes:

[0029] A fourth resistor, wherein a first end of the fourth resistor is coupled to the first end of the first conversion circuit, and a second end of the fourth resistor is coupled to the first end of the voltage stabilizing circuit.

[0030] In some embodiments of the present disclosure, the power supply circuit further includes:

[0031] A second voltage regulator tube, wherein a cathode of the second voltage regulator tube is coupled to the control end of the first switch unit, and an anode of the second voltage regulator tube is coupled to the second end of the first switch unit.

[0032] In some embodiments of the present disclosure, the power supply circuit further includes:

[0033] An absorption circuit is coupled in parallel with the first switch unit.

[0034] In some embodiments of the present disclosure, the absorption circuit includes:

[0035] a fifth resistor, a first end of the fifth resistor being coupled to the first end of the first switch unit;

[0036] A third capacitor, wherein a first end of the third capacitor is coupled to the second end of the fifth resistor, and a second end of the third capacitor is coupled to the second end of the first switch unit.

[0037] According to a second aspect of the present disclosure, a voltage conversion circuit is provided, wherein the voltage conversion circuit comprises the power supply circuit as described above.

[0038] In some embodiments of the present disclosure, the voltage conversion circuit further includes:

[0039] A transformer, the transformer comprising a primary winding and an auxiliary winding, the auxiliary winding being coupled to the power supply circuit as the AC power source;

[0040] a second conversion circuit, wherein an input end of the second conversion circuit is used to couple with an input power supply, an output end of the second conversion circuit is coupled with the primary winding, and the second conversion circuit is used to convert an input voltage of the input power supply and output it to the primary winding;

[0041] The power supply circuit is used to rectify the AC voltage transmitted from the primary winding to the auxiliary winding and output it to the control circuit.

[0042] In some embodiments of the present disclosure, the second conversion circuit includes:

[0043] 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;

[0044] a second switch unit, wherein a first end of the second switch unit is coupled to a second end of the primary winding, and a second end of the second switch unit is coupled to a second output end of the rectifier and filter circuit;

[0045] The control circuit is coupled to a control terminal of the second switch unit.

[0046] In some embodiments of the present disclosure, the transformer further includes a secondary winding; and the voltage conversion circuit further includes:

[0047] A third conversion circuit, wherein the input end of the third conversion circuit is coupled to the secondary winding, the output end of the third conversion circuit is used to couple to a load, and the third conversion circuit is used to rectify the voltage transmitted from the primary winding to the secondary winding and output it to the load.

[0048] In some embodiments of the present disclosure, the voltage conversion circuit includes a flyback circuit, a forward circuit, a half-bridge circuit or a full-bridge circuit.

[0049] According to a third aspect of the present disclosure, a charging device is provided, the charging device comprising the power supply circuit as described above, or the voltage conversion circuit as described above.

[0050] According to a fourth aspect of the present disclosure, an electronic device is provided, the electronic device comprising the power supply circuit as described above, or the voltage conversion circuit as described above.

[0051] The technical solution provided by the embodiments of the present disclosure may have the following beneficial effects:

[0052] The power supply circuit includes a first switch unit, a first conversion circuit and a voltage stabilizing circuit. The first switch unit is coupled between the voltage stabilizing circuit and the AC power supply to rectify the AC voltage output by the AC power supply and output the DC voltage obtained after rectification to the voltage stabilizing circuit. The first conversion circuit is coupled to both the first switch unit and the AC power supply to control the on and off of the first switch unit through the DC voltage. The voltage stabilizing circuit is coupled to both the first switch unit, the AC power supply and the control circuit to stabilize the DC voltage to supply power to the control circuit. Since the on-state power consumption of the first switch unit is low, the power consumption of the power supply circuit is reduced by rectifying with the first switch unit to improve the power supply efficiency of the power supply circuit. In addition, the on and off of the first switch unit is controlled by the first conversion circuit, and the time required for the on and off switching of the first switch unit is short to reduce the possibility of damage to the power supply circuit, thereby improving the reliability of the power supply circuit. At the same time, by stabilizing the DC voltage with the voltage stabilizing circuit, the DC voltage fluctuation caused by the instability of the AC voltage is avoided to reduce the possibility of damage to the control circuit, thereby improving the safety of the power supply circuit.

[0053] 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

[0054] 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.

[0055] Figure 1 is a structural schematic diagram of a power supply circuit provided by an exemplary embodiment of the present disclosure;

[0056] Figure 2 is a structural schematic diagram of a power supply circuit provided by another exemplary embodiment of the present disclosure;

[0057] Figure 3-1 is a structural schematic diagram of a power supply circuit provided by another exemplary embodiment of the present disclosure;

[0058] Figure 3-2 is a structural schematic diagram of a power supply circuit provided by another exemplary embodiment of the present disclosure;

[0059] Figure 4 is a structural schematic diagram of a power supply circuit provided by another exemplary embodiment of the present disclosure;

[0060] Figure 5 is a structural schematic diagram of a power supply circuit provided by another exemplary embodiment of the present disclosure;

[0061] Figure 6 is a structural schematic diagram of a power supply circuit provided by another exemplary embodiment of the present disclosure;

[0062] Figure 7 is a schematic structural diagram of a voltage conversion circuit provided by an exemplary embodiment of the present disclosure;

[0063] Figure 8 is a system block diagram of an electronic device provided by an exemplary embodiment of the present disclosure.

[0064] In the figure:

[0065] 10-first switch unit; 20-first conversion circuit; 21-voltage divider circuit; 30-voltage stabilizing circuit; 31-emitter follower circuit; 40-control circuit; 50-second conversion circuit; 51-rectifier filter circuit; 60-third conversion circuit; 70-load; 400-electronic device; 402-processing component; 404-memory; 406-power component; 408-multimedia component; 410-audio component; 412-input and output interface; 414-sensor component; 416-communication component; 420-processor; AC1-AC power supply; AC2-input power supply; C1-first capacitor; C2-second capacitor Capacitor; C3-third capacitor; C4-fourth capacitor; C5-fifth capacitor; R1-first resistor; R2-second resistor; R3-third resistor; R4-fourth resistor; R5-fifth resistor; RX-variable resistor; T-transformer; N1-primary winding; N2-auxiliary winding; N3-secondary winding; GND1-first ground terminal; GND2-second ground terminal; Q-transistor; T1-first transistor; T2-second transistor; T3-third transistor; D1-first diode; D2-second diode; D3-third diode; D4-fourth diode; ZD1-first voltage regulator; ZD2-second voltage regulator. DETAILED DESCRIPTION

[0066] 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.

[0067] At present, the power supply circuit rectifies the AC voltage of the AC power supply and supplies power to the control circuit, so that the control circuit is in operation to control the voltage output to the load. For example, the control circuit can control the conduction and disconnection of the switch unit in the voltage conversion circuit to control the voltage output to the load by the voltage conversion circuit.

[0068] In the related art, a power supply circuit is provided, including a diode and a capacitor. The diode is coupled between the AC power supply and the control circuit, and the AC voltage output by the AC power supply is rectified, and the control circuit is powered by the rectified DC voltage. The capacitor is coupled between the diode and the AC power supply, and is used to stabilize the DC voltage. However, since the power consumption of the diode is large during the conduction process, the power consumption of the power supply circuit is increased, resulting in low efficiency of the power supply circuit. In addition, since the diode has a reverse recovery time, a large reverse recovery time may cause damage to the power supply circuit, resulting in low reliability of the power supply circuit.

[0069] Based on this, the present disclosure provides a power supply circuit. Since the power consumption of the first switch unit when it is turned on is less than the power consumption of the diode when it is turned on, the power consumption of the power supply circuit is reduced by replacing the diode for rectification with the first switch unit to improve the efficiency of the power supply circuit. In addition, the first switch unit is controlled to be turned on and off by the first conversion circuit. The time required for the first switch unit to be turned on and off is short to avoid damage to the power supply circuit caused by a long reverse recovery time, thereby improving the reliability of the power supply circuit.

[0070] An exemplary embodiment of the present disclosure provides a power supply circuit, such as Figure 1 As shown, the power supply circuit includes a first switch unit 10, a first conversion circuit 20 and a voltage stabilizing circuit 30. The first end of the first switch unit 10 is used to couple with the AC power source AC1, and the first switch unit 10 is used to rectify the AC voltage output by the AC power source AC1 to obtain a DC voltage. The first end of the first conversion circuit 20 is used to couple with the AC power source AC1, the second end of the first conversion circuit 20 is coupled with the second end of the first switch unit 10, the third end of the first conversion circuit 20 is coupled with the control end of the first switch unit 10, and the first conversion circuit 20 is used to control the conduction and disconnection of the first switch unit 10. The first end of the voltage stabilizing circuit 30 is used to couple with the AC power source AC1, the second end of the voltage stabilizing circuit 30 is coupled with the second end of the first switch unit 10, the third end of the voltage stabilizing circuit 30 is used to couple with the control circuit 40, and the voltage stabilizing circuit 30 is used to stabilize the DC voltage to power the control circuit 40.

[0071] In this embodiment, the power supply circuit includes a first switch unit, a first conversion circuit and a voltage stabilizing circuit. The first switch unit is coupled between the voltage stabilizing circuit and the AC power supply to rectify the AC voltage output by the AC power supply and output the DC voltage obtained after rectification to the voltage stabilizing circuit. The first conversion circuit is coupled to both the first switch unit and the AC power supply to control the on and off of the first switch unit through the DC voltage. The voltage stabilizing circuit is coupled to both the first switch unit, the AC power supply and the control circuit to stabilize the DC voltage to supply power to the control circuit. Since the on-state power consumption of the first switch unit is low, the power consumption of the power supply circuit is reduced by rectifying with the first switch unit to improve the power supply efficiency of the power supply circuit. In addition, the on and off of the first switch unit is controlled by the first conversion circuit, and the time required for the on and off switching of the first switch unit is short to reduce the possibility of damage to the power supply circuit, thereby improving the reliability of the power supply circuit. At the same time, by stabilizing the DC voltage with the voltage stabilizing circuit, the DC voltage fluctuation caused by the instability of the AC voltage is avoided to reduce the possibility of damage to the control circuit, thereby improving the safety of the power supply circuit.

[0072] In one embodiment, if Figure 2 As shown, the first switch unit 10 includes a first transistor T1. The first end of the first transistor T1 is used to couple with the first end of the AC power source AC1, the second end of the first transistor T1 is coupled with the second end of the voltage stabilizing circuit 30, and the control end of the first transistor T1 is coupled with the third end of the first conversion circuit 20. The first end of the first transistor T1 is also used to couple with the first ground terminal GND1.

[0073] In this embodiment, since the on-state power consumption of the first transistor is less than the on-state power consumption of the diode, the power consumption of the power supply circuit can be reduced during the rectification of the AC voltage, thereby improving the efficiency of the power supply circuit. At the same time, since the first transistor can be turned on and off quickly, the possibility of damage to the power supply circuit is reduced, thereby improving the reliability of the power supply circuit.

[0074] Exemplarily, the first transistor T1 may be an N-type field effect transistor. The first terminal of the first transistor T1 may be a drain, the second terminal of the first transistor T1 may be a source, and the control terminal of the first transistor T1 may be a gate.

[0075] It is understandable that the first transistor T1 may also be a P-type field effect transistor.

[0076] In one embodiment, the first conversion circuit 20 includes a voltage divider circuit 21. A first end of the voltage divider circuit 21 is used to couple with a second end of the AC power source AC1, a second end of the voltage divider circuit 21 is coupled with a second end of the first switch unit 10, and a third end of the voltage divider circuit 21 is coupled with a control end of the first switch unit 10.

[0077] In this embodiment, when the voltage at the control end of the first switch unit is too large, the first switch unit may be damaged. By dividing the DC voltage through the voltage divider circuit and outputting it to the control end of the first switch unit, the voltage at the control end of the first switch unit can be reduced to avoid damage to the first switch unit, thereby improving the reliability of the power supply circuit. At the same time, by controlling the on and off of the first switch unit through the voltage divider circuit, the structure of the first conversion circuit is simple, thereby reducing the complexity of the power supply circuit structure.

[0078] In one embodiment, if Figure 3-1 As shown, the voltage divider circuit 21 includes a first resistor R1 and a second resistor R2. The first end of the first resistor R1 is used to couple with the second end of the AC power source AC1, and the second end of the first resistor R1 is coupled with the control end of the first switch unit 10. The first end of the second resistor R2 is coupled with the second end of the first resistor R1, and the second end of the second resistor R2 is coupled with the second end of the first switch unit 10.

[0079] In this embodiment, since the structure of the resistor is simple, the complexity of the power supply circuit structure is reduced by forming a voltage divider circuit with the first resistor and the second resistor.

[0080] In one embodiment, if Figure 3-2 As shown, the voltage divider circuit 21 includes a variable resistor RX. A first fixed end of the variable resistor RX is used to couple with a second end of the AC power source AC1, a second fixed end of the variable resistor RX is coupled with a second end of the first switch unit 10, and a variable end of the variable resistor RX is coupled with a control end of the first switch unit 10.

[0081] In this embodiment, since the resistance of the variable resistor is adjustable, controlling the on and off of the first switch unit by using the variable resistor can prevent the voltage at the control end of the first switch unit from being too large, thereby improving the reliability of the power supply circuit.

[0082] In one embodiment, if Figure 4 As shown, the voltage stabilizing circuit 30 includes a first capacitor C1. A first end of the first capacitor C1 is coupled to a second end of the AC power source AC1 and a first end of the control circuit 40, and a second end of the first capacitor C1 is coupled to a second end of the first switch unit 10 and a second end of the control circuit 40.

[0083] In this embodiment, since the rectified DC voltage has large voltage fluctuations, the DC voltage is stabilized by the first capacitor to avoid damage to the control circuit, thereby improving the reliability of the power supply circuit.

[0084] Exemplarily, when the voltage stabilizing circuit 30 includes only the first capacitor C1 , the first end of the first capacitor C1 is the first end and the third end of the voltage stabilizing circuit 30 .

[0085] In one embodiment, the voltage stabilizing circuit 30 further includes an emitter follower circuit 31 and a first voltage stabilizing tube ZD1. The first end of the emitter follower circuit 31 is coupled to the first end of the first capacitor C1, and the second end of the emitter follower circuit 31 is used to couple to the first end of the control circuit 40. The cathode of the first voltage stabilizing tube ZD1 is coupled to the third end of the emitter follower circuit 31, and the anode of the first voltage stabilizing tube ZD1 is used to couple to the second end of the control circuit 40.

[0086] In this embodiment, since the emitter follower circuit has a higher input impedance and a lower output impedance, it helps to improve the stability of the voltage output to the control circuit. By coupling the first voltage regulator tube with the emitter follower circuit, the output voltage of the emitter follower circuit is approximately equal to the reverse breakdown voltage of the first voltage regulator tube, thereby improving the reliability of the power supply circuit.

[0087] In one embodiment, the emitter follower circuit 31 includes a transistor Q and a third resistor R3. The base of the transistor Q is coupled to the cathode of the first voltage regulator ZD1, the collector of the transistor Q is coupled to the first end of the first capacitor C1, and the emitter of the transistor Q is used to couple to the first end of the control circuit 40. The first end of the third resistor R3 is coupled to the collector of the transistor Q, and the second end of the third resistor R3 is coupled to the base of the transistor Q.

[0088] In this embodiment, the third resistor is used to provide a proper bias voltage for the transistor, which can ensure that the transistor works in the amplification region, thereby improving the reliability of the power supply circuit.

[0089] Exemplarily, when the reverse breakdown voltage of the first voltage regulator ZD1 is U1 and the threshold voltage of the transistor Q is U2, the output voltage U3 of the emitter follower circuit 31 is U2-U1. Therefore, the voltage output by the voltage regulator circuit 30 to the control circuit 40 is always kept near U3.

[0090] Exemplarily, a first terminal of the control circuit 40 is coupled to the emitter of the transistor Q, and a second terminal of the control circuit 40 is coupled to the anode of the first voltage regulator tube ZD1.

[0091] In one embodiment, if Figure 4 As shown, the voltage stabilizing circuit 30 further includes a second capacitor C2. A first end of the second capacitor C2 is coupled to a second end of the emitter follower circuit 31, and a second end of the second capacitor C2 is coupled to an anode of the first voltage stabilizing tube ZD1.

[0092] In this embodiment, due to the fluctuation of the voltage of the first capacitor, the voltage outputted from the emitter follower circuit to the control circuit still fluctuates. By coupling the second capacitor with the emitter follower circuit and the first voltage regulator, the voltage outputted from the emitter follower circuit to the control circuit is stabilized, thereby improving the reliability of the power supply circuit.

[0093] In one embodiment, the power supply circuit further includes a current limiting circuit coupled between the first conversion circuit 20 and the voltage stabilizing circuit 30 .

[0094] In this embodiment, since the current output by the AC power supply may be too large, which may cause damage to the voltage stabilizing circuit and the control circuit, the current output by the AC power supply is limited by the current limiting circuit to avoid damage to the control circuit due to excessive current output to the control circuit, thereby improving the reliability of the power supply circuit.

[0095] In one embodiment, if Figure 5 As shown, the current limiting circuit includes a fourth resistor R4 . A first end of the fourth resistor R4 is coupled to a first end of the first conversion circuit 20 , and a second end of the fourth resistor R4 is coupled to a first end of the voltage stabilizing circuit 30 .

[0096] In this embodiment, since the structure of the resistor is simple, the complexity of the power supply circuit structure is reduced by using the fourth resistor to limit the current.

[0097] In one embodiment, the power supply circuit further includes a second voltage regulator tube ZD2 , a cathode of the second voltage regulator tube ZD2 is coupled to the control end of the first switch unit 10 , and an anode of the second voltage regulator tube ZD2 is coupled to the second end of the first switch unit 10 .

[0098] In this embodiment, since the rectified DC voltage has voltage fluctuations, when the voltage fluctuations are too large, the first switch unit may be damaged. By coupling the second voltage regulator tube to the control end of the first switch unit, the maximum voltage of the control end of the first switch unit can be limited to avoid damage to the power supply circuit, thereby improving the reliability of the power supply circuit.

[0099] In one embodiment, the power supply circuit further includes an absorption circuit. The absorption circuit is coupled in parallel with the first switch unit 10 .

[0100] In this embodiment, since a voltage spike will occur 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 coupling the absorption circuit in parallel with the first switch unit to prevent the first switch unit from being damaged, thereby improving the reliability of the power supply circuit.

[0101] In one embodiment, if Figure 6 As shown, the absorption circuit includes a fifth resistor R5 and a third capacitor C3. The first end of the fifth resistor R5 is coupled to the first end of the first switch unit 10. The first end of the third capacitor C3 is coupled to the second end of the fifth resistor R5, and the second end of the third capacitor C3 is coupled to the second end of the first switch unit 10.

[0102] In this embodiment, the fifth resistor and the third capacitor form an RC absorption circuit to suppress voltage spikes. The structure of the absorption circuit is simple, thereby reducing the complexity of the power supply circuit structure.

[0103] For example, in addition to suppressing the voltage spike by using an RC absorption circuit, the voltage spike may also be suppressed by using an RCD absorption circuit, an LC absorption circuit, etc.

[0104] An exemplary embodiment of the present disclosure provides a power supply circuit, which includes a first transistor T1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first capacitor C1, a second capacitor C2, a third capacitor C3, a first voltage regulator ZD1, a second voltage regulator ZD2 and a transistor Q. The first end of the first transistor T1 is coupled to the first end of the AC power source AC1, the first ground terminal GND1 and the first end of the fifth resistor R5, the second end of the first transistor T1 is coupled to the second end of the second resistor R2, the anode of the first voltage regulator ZD1, the anode of the second voltage regulator ZD2, the second end of the first capacitor C1, the second end of the second capacitor C2, the second end of the third capacitor C3 and the second end of the control circuit 40, and the control end of the first transistor T1 is coupled to the second end of the first resistor R1, the first end of the second resistor R2 and the cathode of the second voltage regulator ZD2. The first end of the first resistor R1 is used to be coupled to the second end of the AC power source AC1 and the first end of the fourth resistor R4. The first end of the third resistor R3 is coupled to the collector of the transistor Q, the second end of the fourth resistor R4 and the first end of the first capacitor C1, and the second end of the third resistor R3 is coupled to the base of the transistor Q and the cathode of the first voltage regulator ZD1. The second end of the fifth resistor R5 is coupled to the first end of the third capacitor C3. The emitter of the transistor Q is coupled to the first end of the second capacitor C2 and the first end of the control circuit 40.

[0105] By way of example, the working principle of the power supply circuit is described. When the voltage at the first end of the AC power source AC1 is negative and the voltage at the second end is positive, the first transistor T1 is turned on. When the voltage at the first end of the AC power source AC1 is positive and the voltage at the second end is negative, the first transistor T1 is turned off. By turning the first transistor T1 on and off, rectification of the AC voltage is achieved.

[0106] In an exemplary embodiment, a voltage conversion circuit is provided. The voltage conversion circuit includes the power supply circuit as described above.

[0107] In one embodiment, if Figure 7As shown, the voltage conversion circuit includes a transformer T and a second conversion circuit 50. The transformer T includes a primary winding N1 and an auxiliary winding N2, and the auxiliary winding N2 is coupled to the power supply circuit as an AC power supply AC1. The input end of the second conversion circuit 50 is used to couple with the input power supply AC2, and the output end of the second conversion circuit 50 is coupled with the primary winding N1. The second conversion circuit 50 is used to convert the input voltage of the input power supply AC2 and output it to the primary winding N1. The power supply circuit is used to rectify the AC voltage transmitted from the primary winding N1 to the auxiliary winding N2 and output it to the control circuit 40. The first end of the auxiliary winding N2 is the first end of the AC power supply AC1, and the second end of the auxiliary winding N2 is the second end of the AC power supply AC1.

[0108] In this embodiment, the second conversion circuit and the first conversion circuit are coupled through a transformer so that the voltage converted to the primary winding is changed according to a certain proportion and then output from the auxiliary winding to the first conversion circuit to provide a suitable voltage for the control circuit, thereby improving the reliability of the voltage conversion circuit.

[0109] Exemplarily, the input power source AC2 may be an alternating current power source, for example, an industrial frequency alternating current power source.

[0110] In one embodiment, the second conversion circuit 50 includes a rectifier filter circuit 51, a second switch unit and a control circuit 40. The input end of the rectifier filter circuit 51 is used to couple with the input power supply AC2, and the first output end of the rectifier filter circuit 51 is coupled with the first end of the primary winding N1. The first end of the second switch unit is coupled with the second end of the primary winding N1, and the second end of the second switch unit is coupled with the second output end of the rectifier filter circuit 51. The control circuit 40 is coupled with the control end of the second switch unit.

[0111] In this embodiment, the input voltage is converted into a DC voltage through a rectifier and filter circuit, and the control circuit controls the second switch unit to convert the DC voltage into a high-frequency AC voltage and output it to the auxiliary winding, thereby reducing the size of the transformer and the size of the voltage conversion circuit.

[0112] Exemplarily, the first end of the primary winding N1 and the first end of the auxiliary winding N2 are the same-named ends.

[0113] Exemplarily, the second switch unit includes a second transistor T2. A first terminal of the second transistor T2 is coupled to the second terminal of the primary winding N1, a second terminal of the second transistor T2 is coupled to the second output terminal of the rectifier filter circuit 51, and a control terminal of the second transistor T2 is coupled to the third terminal of the control circuit 40.

[0114] Exemplarily, the rectifier and filter circuit 51 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4 and a fourth capacitor C4. The anode of the first diode D1 is coupled to the first end of the input power supply AC2 and the cathode of the third diode D3, and the cathode of the first diode D1 is coupled to the cathode of the second diode D2, the first end of the fourth capacitor C4 and the first end of the primary winding N1. The anode of the second diode D2 is coupled to the second end of the input power supply AC2 and the cathode of the fourth diode D4. The anode of the third diode D3 is coupled to the anode of the fourth diode D4, the second end of the fourth capacitor C4, the second end of the second switch unit and the first ground terminal GND1.

[0115] In one embodiment, the transformer T further includes a secondary winding N3. The voltage conversion circuit further includes a third conversion circuit 60. An input end of the third conversion circuit 60 is coupled to the secondary winding N3, and an output end of the third conversion circuit 60 is used to couple to a load 70. The third conversion circuit 60 is used to rectify the voltage transmitted from the primary winding N1 to the secondary winding N3 and output it to the load 70.

[0116] In this embodiment, the second conversion circuit and the third 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 third conversion circuit to provide a suitable voltage for the load, thereby improving the reliability of the voltage conversion circuit. At the same time, since the transformer can isolate the second conversion circuit from the third conversion circuit, the third conversion circuit is prevented from being affected by the second conversion circuit, thereby improving the safety of the third conversion circuit.

[0117] Exemplarily, the third conversion circuit 60 includes a third transistor T3 and a fifth capacitor C5. The first end of the third transistor T3 is coupled to the first end of the secondary winding N3, and the second end of the third transistor T3 is coupled to the first end of the fifth capacitor C5, the first end of the load 70, and the second ground terminal GND2. The second end of the fifth capacitor C5 is coupled to the second end of the secondary winding N3 and the second end of the load 70.

[0118] Exemplarily, the first end of the primary winding N1 and the first end of the secondary winding N3 are the same-named ends.

[0119] In one embodiment, the voltage conversion circuit includes a flyback circuit, a forward circuit, a half-bridge circuit or a full-bridge circuit.

[0120] In this embodiment, since the flyback circuit, the forward circuit, the half-bridge circuit, and the full-bridge circuit all have transformers and the control circuits all need to be powered, the power consumption of the voltage conversion circuit is reduced by rectifying with the first switch unit to improve the efficiency of the voltage conversion circuit. In addition, by rectifying with the first switch unit, it is avoided that the first switch unit and the second switch unit are turned on at the same time in the flyback circuit and the first switch unit and the second switch unit are turned on alternately in the forward circuit, thereby improving the reliability of the voltage conversion circuit.

[0121] In an exemplary embodiment, a charging device is provided. The charging device includes the power supply circuit or the voltage conversion circuit as described above.

[0122] In an exemplary embodiment, an electronic device is provided, the electronic device comprising the power supply circuit or the voltage conversion circuit as described above. The electronic device is, for example, a mobile phone, a laptop computer, a tablet computer, a wearable device, and the like.

[0123] refer to Figure 8 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 .

[0124] 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.

[0125] 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.

[0126] 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.

[0127] 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.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] 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.

[0133] 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.

[0134] 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.

[0135] 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 description and examples are to be regarded as exemplary only, and the true scope and spirit of the present disclosure are indicated by the claims.

[0136] 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 power supply circuit, characterized in that: The power supply circuit comprises: a first switch unit, wherein a first end of the first switch unit is used to couple with an AC power source, and the first switch unit is used to rectify an AC voltage output by the AC power source to obtain a DC voltage; a first conversion circuit, wherein a first end of the first conversion circuit is used to couple with the AC power supply, a second end of the first conversion circuit is coupled with a second end of the first switch unit, a third end of the first conversion circuit is coupled with a control end of the first switch unit, and the first conversion circuit is used to control the conduction and disconnection of the first switch unit; A voltage stabilizing circuit, wherein the first end of the voltage stabilizing circuit is used to couple with the AC power supply, the second end of the voltage stabilizing circuit is coupled with the second end of the first switch unit, the third end of the voltage stabilizing circuit is used to couple with the control circuit, and the voltage stabilizing circuit is used to stabilize the DC voltage to power the control circuit.

2. The power supply circuit according to claim 1, characterized in that: The first switch unit comprises: A first transistor, wherein a first end of the first transistor is used to couple with a first end of the AC power supply, a second end of the first transistor is coupled with a second end of the voltage stabilizing circuit, and a control end of the first transistor is coupled with a third end of the first conversion circuit.

3. The power supply circuit according to claim 1, characterized in that: The first conversion circuit comprises: A voltage divider circuit, wherein the first end of the voltage divider circuit is used to couple with the second end of the AC power supply, the second end of the voltage divider circuit is coupled with the second end of the first switch unit, and the third end of the voltage divider circuit is coupled with the control end of the first switch unit.

4. The power supply circuit according to claim 3, characterized in that: The voltage divider circuit comprises: a first resistor, wherein a first end of the first resistor is used to be coupled to a second end of the AC power source, and a second end of the first resistor is coupled to a control end of the first switch unit; a second resistor, wherein a first end of the second resistor is coupled to a second end of the first resistor, and a second end of the second resistor is coupled to a second end of the first switch unit; or A variable resistor, wherein the first fixed end of the variable resistor is used to couple with the second end of the AC power supply, the second fixed end of the variable resistor is coupled with the second end of the first switch unit, and the variable end of the variable resistor is coupled with the control end of the first switch unit.

5. The power supply circuit according to claim 1, characterized in that: The voltage stabilizing circuit comprises: A first capacitor, wherein a first end of the first capacitor is used to couple to a second end of the AC power supply and a first end of the control circuit, and a second end of the first capacitor is coupled to a second end of the first switch unit and a second end of the control circuit.

6. The power supply circuit according to claim 5, characterized in that: The voltage stabilizing circuit further comprises: an emitter follower circuit, wherein a first end of the emitter follower circuit is coupled to a first end of the first capacitor, and a second end of the emitter follower circuit is used to couple to a first end of the control circuit; A first voltage regulator tube, wherein a cathode of the first voltage regulator tube is coupled to the third end of the emitter follower circuit, and an anode of the first voltage regulator tube is used to couple to the second end of the control circuit.

7. The power supply circuit according to claim 6, characterized in that: The emitter follower circuit comprises: A transistor, wherein the base of the transistor is coupled to the cathode of the first voltage regulator tube, the collector of the transistor is coupled to the first end of the first capacitor, and the emitter of the transistor is used to couple to the first end of the control circuit; A third resistor, wherein a first end of the third resistor is coupled to the collector of the transistor, and a second end of the third resistor is coupled to the base of the transistor.

8. The power supply circuit according to claim 6, characterized in that: The voltage stabilizing circuit further includes: A second capacitor, wherein a first end of the second capacitor is coupled to a second end of the emitter follower circuit, and a second end of the second capacitor is coupled to an anode of the first voltage regulator tube.

9. The power supply circuit according to claim 1, characterized in that: The power supply circuit also includes: A current limiting circuit is coupled between the first conversion circuit and the voltage stabilizing circuit.

10. The power supply circuit according to claim 9, characterized in that: The current limiting circuit comprises: A fourth resistor, wherein a first end of the fourth resistor is coupled to the first end of the first conversion circuit, and a second end of the fourth resistor is coupled to the first end of the voltage stabilizing circuit.

11. The power supply circuit according to claim 1, characterized in that: The power supply circuit also includes: A second voltage regulator tube, wherein a cathode of the second voltage regulator tube is coupled to the control end of the first switch unit, and an anode of the second voltage regulator tube is coupled to the second end of the first switch unit.

12. The power supply circuit according to claim 1, characterized in that: The power supply circuit also includes: An absorption circuit is coupled in parallel with the first switch unit.

13. The power supply circuit according to claim 12, characterized in that: The absorption circuit comprises: a fifth resistor, a first end of the fifth resistor being coupled to the first end of the first switch unit; A third capacitor, wherein a first end of the third capacitor is coupled to the second end of the fifth resistor, and a second end of the third capacitor is coupled to the second end of the first switch unit.

14. A voltage conversion circuit, characterized in that: The voltage conversion circuit comprises the power supply circuit according to any one of claims 1 to 13.

15. The voltage conversion circuit according to claim 14, characterized in that: The voltage conversion circuit further includes: A transformer, the transformer comprising a primary winding and an auxiliary winding, the auxiliary winding being coupled to the power supply circuit as the AC power source; a second conversion circuit, wherein an input end of the second conversion circuit is used to couple with an input power supply, an output end of the second conversion circuit is coupled with the primary winding, and the second conversion circuit is used to convert an input voltage of the input power supply and output it to the primary winding; The power supply circuit is used to rectify the AC voltage transmitted from the primary winding to the auxiliary winding and output it to the control circuit.

16. The voltage conversion circuit according to claim 15, characterized in that: The second 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 second switch unit, wherein a first end of the second switch unit is coupled to a second end of the primary winding, and a second end of the second switch unit is coupled to a second output end of the rectifier and filter circuit; The control circuit is coupled to a control terminal of the second switch unit.

17. The voltage conversion circuit according to claim 15, characterized in that: The transformer further includes a secondary winding; and the voltage conversion circuit further includes: A third conversion circuit, wherein the input end of the third conversion circuit is coupled to the secondary winding, the output end of the third conversion circuit is used to couple to a load, and the third conversion circuit is used to rectify the voltage transmitted from the primary winding to the secondary winding and output it to the load.

18. The voltage conversion circuit according to claim 14, characterized in that: The voltage conversion circuit includes a flyback circuit, a forward circuit, a half-bridge circuit or a full-bridge circuit.

19. A charging device, characterized in that: The charging device comprises the power supply circuit according to any one of claims 1 to 13, or the voltage conversion circuit according to any one of claims 14 to 18.

20. An electronic device, characterized in that: The electronic device comprises the power supply circuit according to any one of claims 1 to 13, or the voltage conversion circuit according to any one of claims 14 to 18.

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