Current control circuit, wireless charging receiving circuit, system, chip and equipment

Abstract

The invention provides a current control circuit, a wireless charging receiving circuit, a system, a chip and equipment. Under the condition that the output voltage is greater than or equal to the preset voltage, when the first high-side tube is opened, the current control circuit controls the first low-side tube to be opened, so that a pull-down path formed by the first high-side tube and the first low-side tube exists in the rectifying circuit. Therefore, the input current of the rectifying circuit is shunted through the pull-down path, so that the current flowing to the load in the wireless charging receiving circuit from the first high-side tube is reduced, and the output voltage is reduced. Therefore, the current control circuit controls the turn-on current of the first low-side tube and pulls down the output voltage. Furthermore, compared with the related technology, the current control circuit provided by the invention can perform pull-down on the output voltage without additionally introducing a pull-down resistor and increasing PIN output. Therefore, the application cost of the wireless charging receiving circuit can be saved, and PIN constraint is reduced.

Description

Technical Field

[0001] The present application relates to the field of wireless charging technology, and in particular to a current control circuit, a wireless charging receiving circuit, a chip, a system, and a device. Background Art

[0002] The principle of wireless charging technology is to achieve wireless transmission of electrical energy through electromagnetic field coupling between the transmitting coil in the transmitter end (TX) circuit and the receiving coil in the receiver end (RX) circuit. When the TX circuit supplies too much energy or the load of the RX circuit is light, the output voltage of the rectifier circuit in the RX circuit increases, making the output voltage of the rectifier circuit too high. In this way, the excessive output voltage of the rectifier circuit will break down the power tube and the module circuit used to control the power tube in the RX circuit chip. Therefore, in the related art, when the output voltage of the rectifier circuit is too high, the RX circuit will trigger overvoltage protection, allowing the RX circuit to pull down the output voltage of the rectifier circuit through an additional pull-down resistor to reduce the output voltage of the rectifier circuit.

[0003] However, in the related art, the RX circuit chip needs to introduce an additional pull-down resistor, i.e., an off-chip resistor, and increase the PIN pin output, which results in an increase in the application cost of the RX circuit chip and an increase in the PIN pin constraints. Summary of the Invention

[0004] The present application provides a current control circuit, a wireless charging receiving circuit, a system, a chip, and a device, which can save the application cost of the RX circuit and reduce PIN pin constraints.

[0005] In a first aspect, the present application provides a current control circuit, which is applied to a wireless charging receiving circuit. The wireless charging receiving circuit includes: a rectifier circuit, the rectifier circuit including: two high-side tubes and two low-side tubes, the first high-side tube being one of the two high-side tubes, and the first low-side tube being one of the two low-side tubes; a first end of the current control circuit is electrically connected to the gate of the first low-side tube, a second end of the current control circuit is electrically connected to the source of the first low-side tube, a drain of the first low-side tube is electrically connected to the source of the first high-side tube, and the drain of the first high-side tube is used to output the output voltage of the rectifier circuit;

[0006] The current control circuit is used to control the turn-on current of the first low-side tube when the first high-side tube is turned on, so as to pull down the output voltage when the output voltage is greater than or equal to a preset voltage.

[0007] Through the current control circuit provided in the first aspect, when the output voltage is greater than or equal to the preset voltage, when the first high-side tube is turned on, the current control circuit can control the first low-side tube to turn on, so that there is a pull-down path composed of the first high-side tube and the first low-side tube in the rectifier circuit. In this way, the input current of the rectifier circuit will be shunted through the pull-down path, so that the current flowing from the first high-side tube to the load in the wireless charging receiving circuit is reduced, so that the output voltage is reduced. In this way, the current control circuit can control the turn-on current of the first low-side tube, so that the current flowing from the first high-side tube to the load in the wireless charging receiving circuit is reduced, so that the output voltage is reduced. Furthermore, compared with the related art, the current control circuit provided in the present application can pull down the output voltage without the need to introduce an additional pull-down resistor and increase the PIN pin output. Therefore, it is possible to save the application cost of the wireless charging receiving circuit and reduce the PIN pin constraints.

[0008] In one possible design, the current control circuit includes: a switch tube, a clamping circuit, and a current regulating circuit;

[0009] The first end of the switch tube is electrically connected to the gate of the first low-side tube, the control end of the switch tube is used to receive a control signal, and the control signal is used to control the switching tube to be turned on or off, the second end of the switch tube is electrically connected to the first end of the clamping circuit, the second end of the clamping circuit is electrically connected to the first end of the current regulating circuit, and the second end of the current regulating circuit is electrically connected to the source of the first low-side tube;

[0010] The clamping circuit is configured to clamp the gate voltage of the first low-side transistor to be equal to the voltage of the first terminal of the current regulating circuit through the turned-on switching transistor, so that the turn-on current of the first low-side transistor is correlated with the current of the transistor in the current regulating circuit;

[0011] The current regulating circuit is used to regulate the current of the transistor to control the turn-on current of the first low-side transistor.

[0012] In one possible design, the clamping circuit includes: an operational amplifier, wherein the operational amplifier is a unity-gain operational amplifier;

[0013] The output end of the operational amplifier and the negative phase input end of the operational amplifier are both electrically connected to the second end of the switch tube, and the positive phase input end of the operational amplifier is electrically connected to the first end of the current regulating circuit.

[0014] In one possible design, the current regulating circuit includes: a transistor and a current source;

[0015] The current source is electrically connected to the drain of the transistor, the gate of the transistor is electrically connected to the second end of the clamping circuit, and the source of the transistor is electrically connected to the source of the first low-side transistor;

[0016] The current source is used to provide current to the transistor.

[0017] In one possible design, the rectifier circuit further includes: two drivers, the first driver being one of the two drivers, and the first driver being electrically connected to the gate of the first low-side tube;

[0018] When the current control circuit controls the turn-on current of the first low-side tube, the first driver stops driving the first low-side tube;

[0019] Alternatively, when the current control circuit does not control the turn-on current of the first low-side transistor, the first driver drives the first low-side transistor.

[0020] In a second aspect, the present application provides a wireless charging receiving circuit, comprising: a rectifier circuit, a receiving coil, a first capacitor, a second capacitor, and two current control circuits in the first aspect and in each possible design of the first aspect;

[0021] The first end of the receiving coil is electrically connected to the upper plate of the first capacitor, the lower plate of the first capacitor is electrically connected to the upper plate of the second capacitor and the first input end of the rectifier circuit respectively, the second end of the receiving coil and the lower plate of the second capacitor are both electrically connected to the second input end of the rectifier circuit, the first ends of the two current control circuits are electrically connected to the gate of the low-side tube in the rectifier circuit, the output end of the rectifier circuit is used to output the output voltage of the rectifier circuit, and the second ends of the two current control circuits are electrically connected to the source of the low-side tube.

[0022] In one possible design, the rectifier circuit includes: two high-side transistors, two low-side transistors, and two drivers;

[0023] The drain of the high-side tube is used to output the output voltage, the gate of the high-side tube is used to access a drive signal, and the drive signal is used to drive the high-side tube to be turned on or off. The source of the high-side tube is electrically connected to the drain of the low-side tube one by one, and the first end of the driver and the current control circuit are both electrically connected to the gate of the low-side tube one by one. The input end of the rectifier circuit is electrically connected between the source of the high-side tube and the drain of the low-side tube, and the second end of the current control circuit is electrically connected to the source of the low-side tube one by one.

[0024] The beneficial effects of the wireless charging receiving circuit provided in the second aspect and each possible design of the second aspect can be referred to the beneficial effects brought about by the first aspect and each possible implementation method of the first aspect, and will not be repeated here.

[0025] In a third aspect, the present application provides a wireless charging system, comprising: a wireless charging transmitting circuit and a wireless charging receiving circuit in the above second aspect and various possible designs of the above second aspect.

[0026] In a fourth aspect, the present application provides a chip, comprising: the current control circuit in the first aspect and each possible design of the first aspect, and the wireless charging receiving circuit in the second aspect and each possible design of the second aspect.

[0027] In a fifth aspect, the present application provides an electronic device, comprising: the chip in the fourth aspect above.

[0028] The above description is only an overview of the technical solutions of the embodiments of the present application. In order to more clearly understand the technical means of the embodiments of the present application, they can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiments of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present application, a brief introduction will be given below to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0030] Figure 1 Schematic diagram of the structure of a wireless charging system in related technology;

[0031] Figure 2 A schematic structural diagram of a current control circuit provided in one embodiment of the present application;

[0032] Figure 3 A schematic structural diagram of a current control circuit provided in one embodiment of the present application;

[0033] Figure 4 A schematic structural diagram of a current control circuit provided in one embodiment of the present application;

[0034] Figure 5 A schematic structural diagram of a current control circuit provided in one embodiment of the present application;

[0035] Figure 6A schematic structural diagram of a current control circuit provided in one embodiment of the present application;

[0036] Figure 7 A schematic diagram of the structure of a wireless charging receiving circuit provided in one embodiment of the present application. DETAILED DESCRIPTION

[0037] In this application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a alone, b alone, or c alone can represent: a alone, b alone, c alone, a and b in combination, a and c in combination, b and c in combination, or a, b, and c in combination, where a, b, and c can be single or multiple. In addition, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance.

[0038] The directions or positional relationships indicated by terms such as "center", "longitudinal", "lateral", "up", "down", "left", "right", "front", and "back" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the present application.

[0039] The terms "connected" and "connect" should be interpreted broadly. For example, "connected" or "connected" in a circuit structure can refer not only to a physical connection, but also to an electrical connection or a signal connection. For example, it can be a direct connection, i.e., a physical connection, or an indirect connection through at least one intermediate component, as long as the circuit is interconnected. It can also refer to internal connectivity between two components. Signal connection can refer not only to signal connection through circuits but also to signal connection through media, such as radio waves. Those skilled in the art will understand the specific meanings of the above terms in this application on a case-by-case basis.

[0040] Reference Figure 1 , Figure 1 FIG. 1 is a schematic diagram of the structure of a wireless charging system in the related art. Figure 1As shown, in the RX circuit of the related art, when the output voltage Vrect' of the rectifier circuit is too high, the RX circuit triggers overvoltage protection. Thus, the switch S1' in the RX circuit turns on, allowing the pull-down resistor RCLAMP' to pull down the output voltage Vrect' of the rectifier circuit, thereby reducing the output voltage Vrect' of the rectifier circuit.

[0041] However, the RX circuit chip in the related art needs to introduce an additional pull-down resistor RCLAMP' and increase the PIN pin output, which results in an increase in the application cost of the RX circuit chip and an increase in the PIN pin constraints.

[0042] In order to solve the above technical problems, the present application provides a current control circuit. Figure 2 , Figure 2 This is a schematic diagram of the structure of a current control circuit provided by an embodiment of the present application. Figure 2 As shown, the current control circuit is applied to the wireless charging receiving circuit 1000, and the wireless charging receiving circuit 1000 may include: a rectifier circuit 200. The rectifier circuit 200 may include: two high-side transistors and two low-side transistors.

[0043] The first high-side tube is either one of the two high-side tubes, that is, the first high-side tube can be the second high-side tube QH1 or the third high-side tube QH3. The first low-side tube is either one of the two low-side tubes, that is, the first low-side tube can be the second low-side tube QL2 or the third low-side tube QL4.

[0044] The current control circuit may be a first current control circuit 100 - 1 or a second current control circuit 100 - 2 .

[0045] The first end of the current control circuit is electrically connected to the gate of the first low-side tube, the second end of the current control circuit is electrically connected to the source of the first low-side tube, the drain of the first low-side tube is electrically connected to the source of the first high-side tube, and the drain of the first high-side tube is used to output the output voltage Vrect of the rectifier circuit 200.

[0046] When the first low-side tube is the second low-side tube QL2 , the corresponding first high-side tube is the second high-side tube QH1 . When the first low-side tube is the third low-side tube QL4 , the corresponding first high-side tube is the third high-side tube QH3 .

[0047] When the output voltage Vrect is greater than or equal to the preset voltage, that is, when the output voltage Vrect is too high, when the first high-side tube is turned on, the current control circuit can control the first low-side tube to turn on, so that there is a pull-down path composed of the first high-side tube and the first low-side tube in the rectifier circuit 200. In this way, the input current of the rectifier circuit 200 will be shunted through the pull-down path, so that the current flowing from the first high-side tube to the load in the wireless charging receiving circuit 1000 is reduced. In this way, the current control circuit can control the turn-on current of the first low-side tube, so that the current flowing from the first high-side tube to the load in the wireless charging receiving circuit 1000 is reduced, so that the output voltage Vrect is reduced. Furthermore, compared with the related art, the current control circuit provided in the present application can pull down the output voltage Vrect without the need to additionally introduce a pull-down resistor RCLAMP' and increase the PIN pin output. Thus, the application cost of the wireless charging receiving circuit 1000 can be saved, and the PIN pin constraints can be reduced.

[0048] The following combination Figure 3 and Figure 4 , Figure 3 and Figure 4 Each of the diagrams is a schematic diagram of a current control circuit according to an embodiment of the present application. The working principles of the current control circuit are described in detail using the first current control circuit 100-1 and the second current control circuit 100-2 as examples. The contents are as follows:

[0049] like Figure 3 As shown, when the output voltage Vrect is greater than or equal to a preset voltage, when the rectifier circuit 200 is in the on-phase of the second high-side transistor QH1 and the third low-side transistor QL4, the first current control circuit 100-1 can control the second low-side transistor QL2 to turn on, creating a pull-down path in the rectifier circuit 200 formed by the second high-side transistor QH1 and the second low-side transistor QL2. In this way, the input current IAC1 of the rectifier circuit 200 is shunted through this pull-down path, reducing the current flowing from the second high-side transistor QH1 to the load in the wireless charging receiving circuit 1000. In this way, the first current control circuit 100-1 can control the on-current of the second low-side transistor QL2 to reduce the current flowing from the second high-side transistor QH1 to the load in the wireless charging receiving circuit 1000, thereby reducing the output voltage Vrect of the rectifier circuit 200. Consequently, the current control circuit 100-1 can control the on-current of the second low-side transistor QL2 to pull down the output voltage Vrect.

[0050] The third high-side tube QH3 is turned off.

[0051] like Figure 4As shown, when the output voltage Vrect is greater than or equal to a preset voltage, when the rectifier circuit 200 is in the on-phase of the third high-side transistor QH3 and the second low-side transistor QL2, the second current control circuit 100-2 can control the third low-side transistor QL4 to turn on, creating a pull-down path formed by the third high-side transistor QH3 and the third low-side transistor QL4 in the rectifier circuit 200. In this way, the input current IAC2 of the rectifier circuit 200 is shunted through this pull-down path, reducing the current flowing from the third high-side transistor QH3 to the load in the wireless charging receiving circuit 1000. In this way, the second current control circuit 100-2 can control the on-current of the third low-side transistor QL4 to reduce the current flowing from the third high-side transistor QH3 to the load in the wireless charging receiving circuit 1000, thereby reducing the output voltage Vrect of the rectifier circuit 200. Consequently, the second current control circuit 100-2 can control the on-current of the third low-side transistor QL4 to pull down the output voltage Vrect.

[0052] The second high-side tube QH1 is turned off.

[0053] In some examples, the rectifier circuit 200 may further include: two drivers, where the first driver is any one of the two drivers, that is, the first driver may be the second driver DRIVER1 or the third driver DRIVER2 .

[0054] The first driver is electrically connected to the gate of the first low-side transistor.

[0055] When the current control circuit controls the turn-on current of the first low-side tube, that is, when the output voltage Vrect is greater than or equal to the preset voltage and the output voltage Vrect needs to be pulled down, the first driver stops driving the first low-side tube, that is, the first driver is in a non-working state.

[0056] Alternatively, when the current control circuit does not control the turn-on current of the first low-side transistor, that is, when the output voltage Vrect does not need to be pulled down, the first driver drives the first low-side transistor, that is, the first driver is in a working state.

[0057] Based on this, it can be seen that the current control circuit and the driver do not work at the same time, that is, when the current control circuit is working, the driver is not working. Or, when the current control circuit is not working, the driver is working.

[0058] like Figure 3As shown, when the first current control circuit 100-1 controls the turn-on current of the second low-side transistor QL2, the second driver DRIVER1 does not operate, that is, the second driver DRIVER1 does not drive the gate voltage of the second low-side transistor QL2. When the second current control circuit 100-2 does not control the turn-on current of the third low-side transistor QL4, the third driver DRIVER2 operates, that is, the third driver DRIVER2 drives the gate voltage of the third low-side transistor QL4.

[0059] like Figure 4 As shown, when the second current control circuit 100-2 controls the turn-on current of the third low-side transistor QL4, the third driver DRIVER2 does not operate, that is, the third driver DRIVER2 does not drive the gate voltage of the third low-side transistor QL4. When the first current control circuit 100-1 does not control the turn-on current of the second low-side transistor QL2, the second driver DRIVER1 operates, that is, the second driver DRIVER1 drives the gate voltage of the second low-side transistor QL2.

[0060] The present application provides a current control circuit. When the output voltage is greater than or equal to a preset voltage, when the first high-side tube is turned on, the current control circuit can control the first low-side tube to turn on, so that a pull-down path composed of the first high-side tube and the first low-side tube exists in the rectifier circuit. In this way, the input current of the rectifier circuit will be shunted through the pull-down path, so that the current flowing from the first high-side tube to the load in the wireless charging receiving circuit is reduced, so that the output voltage is reduced. In this way, the current control circuit can control the turn-on current of the first low-side tube, so that the current flowing from the first high-side tube to the load in the wireless charging receiving circuit is reduced, so that the output voltage is reduced. Furthermore, compared with the related art, the current control circuit provided by the present application can pull down the output voltage without the need to introduce an additional pull-down resistor or increase the PIN pin output. Therefore, it is possible to save the application cost of the wireless charging receiving circuit and reduce the PIN pin constraints.

[0061] Based on the description of the above embodiment, a possible implementation of the current control circuit is exemplified. Figure 2-4 As shown, the current control circuit may include: a switch tube, a clamping circuit and a current regulating circuit.

[0062] The first end of the switching tube is electrically connected to the gate of the first low-side tube, the control end of the switching tube is used to receive a control signal, and the control signal is used to control the switching tube to be turned on or off, the second end of the switching tube is electrically connected to the first end of the clamping circuit, the second end of the clamping circuit is electrically connected to the first end of the current regulating circuit, and the second end of the current regulating circuit is electrically connected to the source of the first low-side tube.

[0063] Among them, the switch tube, the clamping circuit and the current regulation circuit can be set separately or integrated, and the embodiments of the present application do not make specific limitations on this.

[0064] When the current control circuit is the first current control circuit 100-1, the switch is the first switch S1, the current regulation circuit is the first current regulation circuit 110-1, and the clamping circuit is the first clamping circuit 120-1. When the current control circuit is the second current control circuit 100-2, the switch is the second switch S2, the current regulation circuit is the second current regulation circuit 110-2, and the clamping circuit is the second clamping circuit 120-2.

[0065] The first end of the switch tube is the first end of the current control circuit, and the second end of the current regulating circuit is the second end of the current control circuit.

[0066] Among them, the switching transistors may include but are not limited to gallium nitride transistors, bipolar junction transistors, insulated gate bipolar transistors, metal-oxide semiconductor field effect transistors, field-controlled thyristors, gate turn-off thyristors and transmission gates.

[0067] For example, when the switch tube is a gallium nitride transistor, the control end of the switch tube refers to the gate of the gallium nitride transistor, the first end of the switch tube can be the drain or source of the gallium nitride transistor, and correspondingly, the second end of the switch tube can be the source or drain of the gallium nitride transistor.

[0068] For example, when the control end of the switch tube refers to the base of the bipolar junction transistor, the first end of the switch tube can be the collector or emitter of the bipolar junction transistor, and correspondingly, the second end of the switch tube can be the emitter or collector of the bipolar junction transistor.

[0069] For example, when the control end of the switch tube refers to the gate of the insulated gate bipolar transistor, the first end of the switch tube can be the collector or emitter of the insulated gate bipolar transistor, and correspondingly, the second end of the switch tube can be the emitter or collector of the insulated gate bipolar transistor.

[0070] For example, when the switching tube is a metal-oxide semiconductor field-effect transistor, the control end of the switching tube refers to the gate of the metal-oxide semiconductor field-effect transistor, the first end of the switching tube can be the drain or source of the metal-oxide semiconductor field-effect transistor, and correspondingly, the second end of the switching tube can be the source or drain of the metal-oxide semiconductor field-effect transistor.

[0071] For example, when the switch tube is a field-controlled thyristor, the control end of the switch tube refers to the gate of the field-controlled thyristor, the first end of the switch tube S can be the drain or source of the field-controlled thyristor, and correspondingly, the second end of the switch tube can be the source or drain of the field-controlled thyristor.

[0072] For example, when the switching tube is a gate-turn-off thyristor, the control end of the switching tube refers to the gate of the gate-turn-off thyristor, the first end of the switching tube can be the cathode or anode of the gate-turn-off thyristor, and correspondingly, the second end of the switching tube can be the cathode or anode of the gate-turn-off thyristor.

[0073] For example, when the control end of the switch tube refers to the port of the transmission gate for accessing the gate control signal, the first end of the switch tube can be the input end or output end of the transmission gate, and correspondingly, the second end of the switch tube can be the input end or output end of the transmission gate.

[0074] When the control signal turns on the switch, the current control circuit can control the turn-on current of the first low-side transistor, that is, the current control circuit is in an operational state. When the control signal turns off the switch, the current control circuit does not control the turn-on current of the first low-side transistor, that is, the current control circuit is in an inoperative state.

[0075] When the output voltage Vrect is greater than or equal to the preset voltage, that is, when the output voltage Vrect needs to be pulled down, the control signal controls the switch tube to turn on, so that the current control circuit is in an operating state. When the output voltage Vrect is less than the preset voltage, that is, when the output voltage Vrect does not need to be pulled down, the control signal controls the switch tube to turn off, so that the current control circuit is in an inoperative state.

[0076] The clamping circuit can clamp the gate voltage of the first low-side tube to be equal to the first terminal voltage of the current regulation circuit through the turned-on switching tube, so that the turn-on current of the first low-side tube is related to the current of the transistor in the current regulation circuit, that is, the turn-on current of the first low-side tube is proportional to the current of the transistor.

[0077] When the first current control circuit 100-1 controls the turn-on current of the second low-side transistor QL2, the first clamping circuit 120-1 can clamp the gate voltage of the second low-side transistor QL2 to be equal to the voltage at the first terminal of the first current regulation circuit 110-1 by turning on the first switch transistor S1. When the second current control circuit 100-2 controls the turn-on current of the third low-side transistor QL4, the second clamping circuit 120-2 can clamp the gate voltage of the third low-side transistor QL4 to be equal to the voltage at the first terminal of the second current regulation circuit 110-2 by turning on the second switch transistor S2.

[0078] In this way, the current regulating circuit can control the turn-on current of the first low-side transistor by regulating the current of the transistor M. Thus, when the first high-side transistor is turned on, the current control circuit can control the turn-on current of the first low-side transistor.

[0079] Reference Figure 5 and Figure 6 , Figure 5 and Figure 6 These are all structural diagrams of a current control circuit provided by an embodiment of the present application. Figure 5 As shown, when the output voltage Vrect is less than the preset voltage, that is, when the output voltage Vrect does not need to be pulled down, when the second low-side transistor QL2 is in the off phase, the second driver DRIVER1 pulls down the gate voltage of the second low-side transistor QL2, turning off the second low-side transistor QL2. When the third low-side transistor QL4 is in the on phase, the third driver DRIVER2 pulls up the gate voltage of the third low-side transistor QL4, turning on the third low-side transistor QL4.

[0080] like Figure 6 As shown, when the output voltage Vrect is less than the preset voltage, that is, when the output voltage Vrect does not need to be pulled down, when the second low-side transistor QL2 is in the on phase, the second driver DRIVER1 pulls up the gate voltage of the second low-side transistor QL2, turning on the second low-side transistor QL2. When the third low-side transistor QL4 is in the off phase, the third driver DRIVER2 pulls down the gate voltage of the third low-side transistor QL4, turning off the third low-side transistor QL4.

[0081] Based on the description of the above embodiment, a possible implementation of the clamping circuit is exemplified. Figure 2-6 As shown, the clamping circuit may include: an operational amplifier.

[0082] The operational amplifier is a unity-gain operational amplifier.

[0083] The output end of the operational amplifier and the negative phase input end of the operational amplifier are both electrically connected to the second end of the switch tube, and the positive phase input end of the operational amplifier is electrically connected to the first end of the current regulating circuit.

[0084] The output terminal of the operational amplifier and the negative phase input terminal of the operational amplifier are both the first terminals of the clamping circuit, and the positive phase input terminal of the operational amplifier is the second terminal of the clamping circuit.

[0085] Based on the description of the above embodiment, a possible implementation of the current regulating circuit is exemplified. Figure 2-6 As shown, the current regulating circuit may include: a transistor and a current source.

[0086] When the current regulating circuit is the first current regulating circuit 110 - 1 , the transistor is the first transistor M2 , and when the current regulating circuit is the second current regulating circuit 110 - 2 , the transistor is the second transistor M4 .

[0087] The current source is electrically connected to the drain of the transistor, the gate of the transistor is electrically connected to the second end of the clamping circuit, and the source of the transistor is electrically connected to the source of the first low-side tube.

[0088] The gate of the transistor is the first end of the current regulating circuit, and the source of the transistor is the second end of the current regulating circuit.

[0089] The current source can provide current to the transistor, so that the current regulating circuit can regulate the current of the transistor to control the turn-on current of the first low-side transistor.

[0090] This application also provides a wireless charging receiving circuit. Figure 7 , Figure 7 This is a schematic diagram of the structure of a wireless charging receiving circuit provided in one embodiment of the present application. Figure 7 As shown, the wireless charging receiving circuit 1000 may include: a rectifier circuit 200 , a receiving coil Ls, a first capacitor Cs, a second capacitor Cd1 and two current control circuits 100 .

[0091] The first end of the receiving coil Ls is electrically connected to the upper plate of the first capacitor Cs, the lower plate of the first capacitor Cs is electrically connected to the upper plate of the second capacitor Cd1 and the first input terminal AC1 of the rectifier circuit 200, respectively. The second end of the receiving coil Ls and the lower plate of the second capacitor Cd1 are both electrically connected to the second input terminal AC2 of the rectifier circuit 200. The first ends of the two current control circuits 100 are electrically connected to the gate of the low-side tube in the rectifier circuit 200. The output end of the rectifier circuit 200 is used to output the output voltage Vrect of the rectifier circuit 200. The second ends of the two current control circuits 100 are electrically connected to the source of the low-side tube.

[0092] Based on the description of the above embodiment, a possible implementation of the rectifier circuit 200 is exemplified. Figure 2-6 As shown, the rectifier circuit 200 may include: two high-side transistors, two low-side transistors and two drivers.

[0093] The drain of the high-side tube is used to output the output voltage Vrect, the gate of the high-side tube is used to access the drive signal, the drive signal is used to drive the high-side tube to turn on or off, the source of the high-side tube is electrically connected to the drain of the low-side tube one by one, the first end of the driver and the current control circuit are both electrically connected to the gate of the low-side tube one by one, the input end of the rectifier circuit 200 is electrically connected between the source of the high-side tube and the drain of the low-side tube, and the second end of the current control circuit is electrically connected to the source of the low-side tube one by one.

[0094] The first input terminal AC1 of the rectifier circuit 200 is electrically connected between the source of the second high-side transistor QH1 and the drain of the second low-side transistor QL2, and the second input terminal AC2 of the rectifier circuit 200 is electrically connected between the source of the third high-side transistor QH3 and the drain of the third low-side transistor QL4.

[0095] The wireless charging receiving circuit provided in the embodiment of the present application has the same beneficial effects as the current control circuit provided in the embodiment of the present application, and will not be described in detail here.

[0096] This application also provides a wireless charging receiving system. Figure 7 As shown, the wireless charging system 10000 may include: a wireless charging transmitting circuit 2000 and a wireless charging receiving circuit 1000 .

[0097] An embodiment of the present application also provides a chip, including: a current control circuit and a wireless charging receiving circuit.

[0098] The current control circuit and the wireless charging receiving circuit may be chips or circuit modules.

[0099] The chip provided in the embodiment of the present application has the same beneficial effects as the current control circuit provided in the embodiment of the present application, which will not be repeated here.

[0100] An embodiment of the present application also provides an electronic device, including: a chip.

[0101] In this application, electronic devices may include but are not limited to: tablet computers, smartphones, smart watches, and home appliances.

[0102] The electronic device provided in the embodiment of the present application has the same beneficial effects as the chip provided in the embodiment of the present application, which will not be repeated here.

[0103] Finally, it should be noted that the above embodiments are merely specific implementations of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A current control circuit, characterized in that: The current control circuit is applied to a wireless charging receiving circuit, which includes a rectifier circuit, the rectifier circuit including two high-side tubes and two low-side tubes, the first high-side tube being one of the two high-side tubes, and the first low-side tube being one of the two low-side tubes; a first end of the current control circuit is electrically connected to the gate of the first low-side tube, a second end of the current control circuit is electrically connected to the source of the first low-side tube, a drain of the first low-side tube is electrically connected to the source of the first high-side tube, and the drain of the first high-side tube is used to output the output voltage of the rectifier circuit; The current control circuit is used to control the turn-on current of the first low-side tube when the first high-side tube is turned on, so as to pull down the output voltage when the output voltage is greater than or equal to a preset voltage.

2. The circuit according to claim 1, wherein: The current control circuit includes: a switch tube, a clamping circuit and a current regulating circuit; The first end of the switch tube is electrically connected to the gate of the first low-side tube, the control end of the switch tube is used to receive a control signal, and the control signal is used to control the switching tube to be turned on or off, the second end of the switch tube is electrically connected to the first end of the clamping circuit, the second end of the clamping circuit is electrically connected to the first end of the current regulating circuit, and the second end of the current regulating circuit is electrically connected to the source of the first low-side tube; The clamping circuit is configured to clamp the gate voltage of the first low-side transistor to be equal to the voltage of the first terminal of the current regulating circuit through the turned-on switching transistor, so that the turn-on current of the first low-side transistor is correlated with the current of the transistor in the current regulating circuit; The current regulating circuit is used to regulate the current of the transistor to control the turn-on current of the first low-side transistor.

3. The circuit according to claim 2, characterized in that The clamping circuit includes: an operational amplifier, wherein the operational amplifier is a unity gain operational amplifier; The output end of the operational amplifier and the negative phase input end of the operational amplifier are both electrically connected to the second end of the switch tube, and the positive phase input end of the operational amplifier is electrically connected to the first end of the current regulating circuit.

4. The circuit according to claim 2, characterized in that The current regulating circuit includes: a transistor and a current source; The current source is electrically connected to the drain of the transistor, the gate of the transistor is electrically connected to the second end of the clamping circuit, and the source of the transistor is electrically connected to the source of the first low-side transistor; The current source is used to provide current to the transistor.

5. The circuit according to any one of claims 1 to 4, characterized in that: The rectifier circuit further includes: two drivers, the first driver being one of the two drivers, the first driver being electrically connected to the gate of the first low-side tube; When the current control circuit controls the turn-on current of the first low-side tube, the first driver stops driving the first low-side tube; Alternatively, when the current control circuit does not control the turn-on current of the first low-side transistor, the first driver drives the first low-side transistor.

6. A wireless charging receiving circuit, characterized in that: include: A rectifier circuit, a receiving coil, a first capacitor, a second capacitor, and two current control circuits according to any one of claims 1 to 5; The first end of the receiving coil is electrically connected to the upper plate of the first capacitor, the lower plate of the first capacitor is electrically connected to the upper plate of the second capacitor and the first input end of the rectifier circuit respectively, the second end of the receiving coil and the lower plate of the second capacitor are both electrically connected to the second input end of the rectifier circuit, the first ends of the two current control circuits are electrically connected to the gate of the low-side tube in the rectifier circuit, the output end of the rectifier circuit is used to output the output voltage of the rectifier circuit, and the second ends of the two current control circuits are electrically connected to the source of the low-side tube.

7. The circuit according to claim 6, characterized in that The rectifier circuit includes: two high-side tubes, two low-side tubes and two drivers; The drain of the high-side tube is used to output the output voltage, the gate of the high-side tube is used to access a drive signal, and the drive signal is used to drive the high-side tube to be turned on or off. The source of the high-side tube is electrically connected to the drain of the low-side tube one by one, and the first end of the driver and the current control circuit are both electrically connected to the gate of the low-side tube one by one. The input end of the rectifier circuit is electrically connected between the source of the high-side tube and the drain of the low-side tube, and the second end of the current control circuit is electrically connected to the source of the low-side tube one by one.

8. A wireless charging system, characterized in that: include: A wireless charging transmitting circuit and a wireless charging receiving circuit as claimed in claim 6 or 7.

9. A chip, characterized in that: include: The current control circuit according to any one of claims 1 to 5 and the wireless charging receiving circuit according to claim 6 or 7.

10. An electronic device, characterized in that: include: The chip as claimed in claim 9.

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