Switched capacitor voltage converter capable of preventing reverse electric leakage, chip and electronic equipment

Abstract

The invention provides a reverse electric leakage prevention switched capacitor voltage converter, chip and electronic equipment, and the converter comprises a logic control circuit, a first switching circuit, a second switching circuit, and a switched capacitor voltage conversion circuit which comprises an input voltage end, an output voltage end, and two electric leakage paths. Each electric leakage path comprises two electric leakage branches, and each electric leakage branch comprises two switch tubes; when the switched capacitor voltage converter is in a non-working state and the input voltage is lower than the output voltage, the logic control circuit controls the first switching circuit, so that the anodes of the body diodes of the first target switching tube and the second target switching tube are both connected with the ground; and the second switching circuit is controlled, so that the control ends of the first target switching tube and the second target switching tube are conducted with the ground. By cutting off the body diode of the switching tube and the path of electric leakage of the channel, reverse electric leakage is prevented, the chip area is reduced, the cost is reduced, and the charging efficiency is improved.

Description

Technical Field

[0001] The present application relates to the technical field of power management chips, and in particular to a reverse leakage-proof switched capacitor voltage converter, chip, and electronic device. Background Art

[0002] A switched capacitor voltage converter is a DC-DC converter that uses capacitors to store energy. Compared to inductors, capacitors have higher energy density. Therefore, the conversion efficiency of a switched capacitor voltage converter that uses capacitors to achieve energy transmission is much higher than that of a voltage converter that uses inductors to achieve energy transmission. Switched capacitor voltage converters are widely used in various charging scenarios due to their high energy conversion efficiency to achieve voltage and current conversion between inputs and outputs of different proportions. Switched capacitor voltage converters achieve higher power density and multiple output functions with a smaller overall circuit solution.

[0003] See also Figure 1 , Figure 1 A single-input multi-output switched capacitor voltage converter is provided for related technologies, such as Figure 1 As shown, the switched capacitor voltage converter can control the connection relationship of capacitors C1A, C1B, C2A, and C2B by controlling the on or off state of power tubes M1 to M16, thereby realizing conversion of different proportions between input and output. Figure 1 In the example, the input terminal IN_1 is connected to the voltage VIN, the first output terminal OUT_1 outputs the first voltage VOUT, and the second output terminal VO1_1 outputs the second voltage VMID, thus realizing the function of single input and multiple output. Figure 1 , by controlling the power tubes M1, M4, M7, M9, M11, M12, M14 and M15 to be turned on, and controlling the power tubes M2, M3, M5, M6, M8, M10, M13 and M16 to be turned off, through the series-parallel relationship between the capacitors C1A, C1B, C2A and C2B, a 4:1 voltage reduction function can be achieved, that is, VIN=4*VOUT.

[0004] In actual application of the switched capacitor voltage converter, when the voltage VIN leaks to a low voltage, the first voltage VOUT will leak to VIN through the switched capacitor voltage converter, resulting in a waste of electric energy. Summary of the invention

[0005] The present application provides a reverse leakage-proof switched capacitor voltage converter, chip, and electronic device to reduce chip area, reduce costs, and improve charging efficiency. The specific technical solution is as follows:

[0006] In a first aspect, the present application provides a reverse leakage-proof switched capacitor voltage converter, the switched capacitor voltage converter comprising: a logic control circuit, a first switch circuit, a second switch circuit, and a switched capacitor voltage conversion circuit, the switched capacitor voltage conversion circuit comprising an input voltage terminal, an output voltage terminal, a first leakage path, and a second leakage path, the first leakage path comprising a first leakage branch and a second leakage branch, the second leakage path comprising a third leakage branch and a fourth leakage branch, the first leakage branch, the second leakage branch, the third leakage branch, and the fourth leakage branch each comprising two switch tubes;

[0007] When the switched capacitor voltage converter is in a non-operating state, and the input voltage connected to the input voltage terminal is lower than the output voltage output by the output voltage terminal, and the absolute value of the difference between the input voltage and the output voltage is greater than a preset threshold:

[0008] The logic control circuit is used to control the first switch circuit so that the anodes of the body diodes of the first target switch tube and the second target switch tube are both connected to the ground; and to control the second switch circuit so that the control ends of the first target switch tube and the second target switch tube are both connected to the ground; wherein the first target switch tube is any one of the switch tubes in the first leakage branch, and the second target switch tube is any one of the switch tubes in the third leakage branch, or the first target switch tube is any one of the switch tubes in the second leakage branch, and the second target switch tube is any one of the switch tubes in the fourth leakage branch.

[0009] In a possible design, for any of the target switch tubes:

[0010] The common end of the first switch circuit is electrically connected to the anode of the body diode of the target switch tube, the first end of the first switch circuit is grounded, and the second end of the first switch circuit is electrically connected to the first end of the target switch tube;

[0011] The common end of the second switch circuit is electrically connected to the control end of the target switch tube, the first end of the second switch circuit is grounded, and the second end of the second switch circuit is electrically connected to the driving voltage end.

[0012] In one possible design, when the switched capacitor voltage converter is in an operating state, the logic control circuit is used to control the first switch circuit so that the anodes of the body diodes of the first target switch tube and the second target switch tube are both connected to the first end of the target switch tube; and control the second switch circuit so that the control ends of the first target switch tube and the second target switch tube are both connected to the driving voltage end, wherein the driving voltage end is electrically connected to the logic control circuit.

[0013] In a possible design, the switched capacitor voltage conversion circuit includes: a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a fifth switch tube, a sixth switch tube, a seventh switch tube, an eighth switch tube, a ninth switch tube, a tenth switch tube, an eleventh switch tube, a twelfth switch tube, a thirteenth switch tube, a fourteenth switch tube, a fifteenth switch tube, a sixteenth switch tube, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, and a sixth capacitor;

[0014] The first end of the first switch tube is electrically connected to the first end of the first capacitor and the second end of the third switch tube respectively, and the second end of the first switch tube is electrically connected to the second end of the sixteenth switch tube and the input voltage end respectively;

[0015] The first end of the second switch tube is grounded, and the second end of the second switch tube is electrically connected to the second end of the first capacitor and the first end of the fourth switch tube respectively;

[0016] The first end of the third switch tube is electrically connected to the second end of the fifth switch tube, the first end of the fifth capacitor, the second end of the twelfth switch tube and the first end of the fourteenth switch tube respectively;

[0017] The second end of the fourth switch tube is electrically connected to the first end of the twelfth switch tube, the second end of the sixth switch tube, and the first end of the second capacitor respectively;

[0018] The first end of the fifth switch tube is electrically connected to the second end of the thirteenth switch tube, the second end of the eleventh switch tube, and the first end of the fourth capacitor respectively;

[0019] The first end of the sixth switch tube is electrically connected to the second end of the seventh switch tube, the first end of the eleventh switch tube, the second end of the tenth switch tube and the first end of the sixth capacitor respectively;

[0020] The first end of the seventh switch tube is electrically connected to the second end of the second capacitor and the second end of the eighth switch tube respectively;

[0021] The first end of the eighth switch tube is grounded;

[0022] The first end of the ninth switch tube is grounded, and the second end of the ninth switch tube is electrically connected to the first end of the tenth switch tube and the second end of the fourth capacitor respectively;

[0023] The first end of the thirteenth switch tube is electrically connected to the second end of the third capacitor and the second end of the fifteenth switch tube respectively;

[0024] The second end of the fourteenth switch tube is electrically connected to the first end of the third capacitor and the first end of the sixteenth switch tube respectively;

[0025] The first end of the fifteenth switch is grounded, the second end of the fifth capacitor is grounded, and the second end of the sixth capacitor is grounded;

[0026] Control ends of the first switch tube, the second switch tube, the third switch tube, the fourth switch tube, the fifth switch tube, the sixth switch tube, the seventh switch tube, the eighth switch tube, the ninth switch tube, the tenth switch tube, the eleventh switch tube, the twelfth switch tube, the thirteenth switch tube, the fourteenth switch tube, the fifteenth switch tube and the sixteenth switch tube are all electrically connected to the logic control circuit.

[0027] In a possible design, the first leakage path includes: the first switch tube, the third switch tube, the fifth switch tube and the eleventh switch tube, and the second leakage path includes: the sixth switch tube, the twelfth switch tube, the fourteenth switch tube and the sixteenth switch tube.

[0028] In one possible design, the first leakage branch includes: the first switch tube and the third switch tube, the second leakage branch includes: the fifth switch tube and the eleventh switch tube, the third leakage branch includes: the fourteenth switch tube and the sixteenth switch tube, and the fourth leakage branch includes: the sixth switch tube and the twelfth switch tube.

[0029] In a possible design, the preset threshold is a minimum value of four times the sum of the forward conduction threshold of the body diode and the conduction thresholds of the four switch tubes on the leakage path.

[0030] In a possible design, the first switch tube, the second switch tube, the third switch tube, the fourth switch tube, the fifth switch tube, the sixth switch tube, the seventh switch tube, the eighth switch tube, the ninth switch tube, the tenth switch tube, the eleventh switch tube, the twelfth switch tube, the thirteenth switch tube, the fourteenth switch tube, the fifteenth switch tube and the sixteenth switch tube are all N-type switch tubes.

[0031] In a second aspect, the present application provides a chip, comprising: a switched capacitor voltage converter as described in the first aspect.

[0032] In a third aspect, the present application provides an electronic device, comprising: the chip as described in the second aspect.

[0033] Beneficial effects of the embodiments of the present application:

[0034] In an embodiment of the present application, when the switched capacitor voltage converter is in a non-operating state, and the input voltage connected to the input voltage terminal is lower than the output voltage outputted by the output voltage terminal, and the absolute value of the difference between the input voltage and the output voltage is greater than a preset threshold value, the first switch circuit is controlled by the logic control circuit so that the anodes of the body diodes of the first target switch tube and the second target switch tube are both connected to the ground, cutting off the path for leakage through the body diode of the switch tube; and the second switch circuit is controlled so that the control terminals of the first target switch tube and the second target switch tube are both connected to the ground, cutting off the path for reverse leakage through the channel of the switch tube. By cutting off the path for leakage of the body diode and the channel of the switch tube, the leakage path from the output voltage terminal OUT to the input voltage terminal IN is completely cut off, preventing reverse leakage of the switched capacitor voltage converter. Since there is no need to introduce additional power tubes in the present application, the chip area is reduced, the cost is reduced, and the charging efficiency is improved.

[0035] The beneficial effects provided in the above-mentioned second aspect and various possible designs of the above-mentioned second aspect can refer to the beneficial effects brought about by the above-mentioned first aspect and various possible implementation methods of the first aspect, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other embodiments can also be obtained based on these drawings.

[0037] Figure 1 A schematic diagram of the structure of a single-input multi-output switched capacitor voltage converter provided in the related art;

[0038] Figure 2 A leakage prevention circuit provided for related technologies;

[0039] Figure 3 A schematic diagram of the structure of a reverse leakage-proof switched capacitor voltage converter provided in an embodiment of the present application;

[0040] Figure 4 A circuit diagram of a reverse leakage-proof switched capacitor voltage converter provided in an embodiment of the present application. DETAILED DESCRIPTION

[0041] In this application, "at least one" means one or more, and "plurality" means 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: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects 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 items or plural items. For example, at least one of a, b, or c alone can represent: a, b, c, a and b, a and c, or a, b, and c, where a, b, and c can be single or multiple. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0042] 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, and therefore should not be understood as a limitation on the present application.

[0043] The terms "connected" and "connected" should be understood in a broad sense. For example, the "connected" or "connected" of a circuit structure can refer to not only physical connection, but also electrical connection or signal connection. For example, it can be directly connected, that is, physically connected, or indirectly connected through at least one intermediate element, as long as the circuit is connected, or it can be the internal connection of two elements; signal connection can refer to signal connection through a circuit or through a media medium, such as radio waves. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] In the related art, in order to prevent the output end of the switched capacitor voltage converter from leaking to the input end, causing a waste of electric energy, a leakage prevention circuit is provided, see Figure 2 ,like Figure 2 As shown, the solution inserts a power tube QB between the input terminal IN_1 and the switched capacitor voltage converter, and the body diode of the power tube QB points from VIN to PMID. When the power tube QB is turned off, the reverse leakage channel from the output terminal OUT_1 to the input terminal IN_1 in the switched capacitor voltage converter can be directly cut off.

[0045] See also Figure 2The technical solution of additionally inserting the power tube QB can prevent the output terminal OUT_1 in the switched capacitor voltage converter from leaking to the input terminal IN_1, but the additionally inserted power tube QB requires additional area overhead, which will increase the chip area and increase the cost. In addition, during the normal operation of the switched capacitor voltage converter, the charging current flowing in from the input terminal IN_1 will flow through the power tube QB, generating additional power loss, resulting in a decrease in charging efficiency and increased chip heat generation.

[0046] In order to solve the problems of large chip area, high cost and low charging efficiency caused by the introduction of additional power tubes in the related technology, an embodiment of the present application provides a reverse leakage-proof switched capacitor voltage converter, which can prevent the reverse leakage of the switched capacitor voltage converter without introducing a power tube.

[0047] In order to reduce chip area, lower costs, and improve charging efficiency, the embodiments of the present application provide a reverse leakage-proof switched capacitor voltage converter, chip, and electronic device.

[0048] The reverse leakage-proof switched capacitor voltage converter may be a chip or a circuit module.

[0049] The chip may include a switched capacitor voltage converter that is protected against reverse leakage.

[0050] In this application, electronic devices may include, but are not limited to: adapters, chargers, tablet computers, smart home devices, vehicles, and wearable devices.

[0051] See also Figure 3 , Figure 3 A schematic diagram of a reverse leakage-proof switched capacitor voltage converter 1000 provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, the reverse leakage-proof switched capacitor voltage converter 1000 includes: a logic control circuit 100, a first switch circuit 200, a second switch circuit 300, and a switched capacitor voltage conversion circuit 400. The switched capacitor voltage conversion circuit 400 includes an input voltage terminal IN, an output voltage terminal OUT, a first leakage path and a second leakage path. The first leakage path includes a first leakage branch and a second leakage branch. The second leakage path includes a third leakage branch and a fourth leakage branch. The first leakage branch, the second leakage branch, the third leakage branch, and the fourth leakage branch each include two switching tubes.

[0052] When the switched capacitor voltage converter is in a non-operating state, and the input voltage Vin connected to the input voltage terminal IN is lower than the output voltage Vout outputted by the output voltage terminal OUT, and the absolute value of the difference between the input voltage Vin and the output voltage Vout is greater than a preset threshold:

[0053] The logic control circuit 100 is used to control the first switch circuit 200 so that the anodes of the body diodes of the first target switch tube and the second target switch tube are both connected to the ground; and control the second switch circuit 300 so that the control ends of the first target switch tube and the second target switch tube are both connected to the ground; wherein the first target switch tube is any one of the switch tubes in the first leakage branch, and the second target switch tube is any one of the switch tubes in the third leakage branch, or the first target switch tube is any one of the switch tubes in the second leakage branch, and the second target switch tube is any one of the switch tubes in the fourth leakage branch.

[0054] When the input voltage Vin of the switched capacitor voltage converter leaks to a low voltage, making the input voltage Vin lower than the output voltage Vout, and when the absolute value of the difference between the input voltage Vin and the output voltage Vout is greater than a preset threshold, there will be a problem of the output voltage Vout leaking back to the input voltage Vin.

[0055] The leakage path from the output voltage terminal OUT to the input voltage terminal IN of the switched capacitor voltage converter includes a first leakage path and a second leakage path, the first leakage path includes a first leakage branch and a second leakage branch, the second leakage path includes a third leakage branch and a fourth leakage branch, and the first leakage branch, the second leakage branch, the third leakage branch, and the fourth leakage branch each include two switch tubes. That is, the first leakage path and the second leakage path each include four switch tubes, and the output voltage Vout of the output voltage terminal OUT needs to pass through four switch tubes before it can leak to the input voltage terminal IN. The preset threshold is related to the forward conduction threshold of the body diode of the switch tube and the conduction threshold of the switch tube, and the relationship between the preset threshold and the two will be described in detail later.

[0056] The main reasons for reverse leakage in the switched capacitor voltage converter include two aspects: first, leakage from the output voltage Vout to the input voltage Vin occurs through the body diode of the switch tube; second, in conventional designs, since the gate voltage of the switch tube will be biased to the source of the switch tube, when the input voltage Vin is too low, the voltage difference between the gate and the drain of the switch tube will be greater than the switch threshold voltage, causing the output voltage Vout to leak from the output voltage Vout to the input voltage Vin through the channel of the switch tube. That is, reverse leakage in the switched capacitor voltage converter mainly occurs through the body diode of the switch tube, and when the voltage difference between the gate and the drain of the switch tube is greater than the switch threshold voltage, reverse leakage occurs through the channel of the switch tube.

[0057] Based on the analysis of the causes of reverse leakage in the switched capacitor voltage converter, when the switched capacitor voltage converter is in a non-working state, in order to prevent reverse leakage of the switched capacitor voltage converter, the present application controls the first switching circuit through a logic control circuit so that the anodes of the body diodes of the first target switching tube and the second target switching tube are both connected to the ground, thereby cutting off the leakage path through the body diodes of the switching tubes; and controls the second switching circuit so that the control ends of the first target switching tube and the second target switching tube are both connected to the ground. At this time, the voltage difference between the gate and the drain of the switching tube is less than the switching threshold voltage, thereby cutting off the reverse leakage path through the channel of the switching tube.

[0058] In order to effectively prevent reverse leakage of the switched capacitor voltage converter, it is necessary to cut off all leakage paths from the output voltage terminal OUT to the input voltage terminal IN, that is, it is necessary to cut off the first leakage path and the second leakage path. Since the first leakage path includes the first leakage branch and the second leakage branch, the second leakage path includes the third leakage branch and the fourth leakage branch, the first leakage branch, the second leakage branch, the third leakage branch and the fourth leakage branch all include two switching tubes. Therefore, at least two switching tubes need to be selected to completely cut off the first leakage path and the second leakage path to prevent the occurrence of reverse leakage.

[0059] To this end, the first target switch tube can be any switch tube in the first leakage branch, the second target switch tube can be any switch tube in the third leakage branch, or the first target switch tube can be any switch tube in the second leakage branch, and the second target switch tube can be any switch tube in the fourth leakage branch.

[0060] In an embodiment of the present application, when the switched capacitor voltage converter is in a non-operating state, and the input voltage connected to the input voltage terminal is lower than the output voltage outputted by the output voltage terminal, and the absolute value of the difference between the input voltage and the output voltage is greater than a preset threshold value, the first switch circuit is controlled by the logic control circuit so that the anodes of the body diodes of the first target switch tube and the second target switch tube are both connected to the ground; and the second switch circuit is controlled so that the control terminals of the first target switch tube and the second target switch tube are both connected to the ground. By cutting off the leakage path of the body diode and the channel of the switch tube, the leakage path from the output voltage terminal OUT to the input voltage terminal IN is completely cut off, thereby preventing reverse leakage of the switched capacitor voltage converter. Since no additional power tubes need to be introduced in the present application, the chip area is reduced, the cost is reduced, and the charging efficiency is improved.

[0061] In one possible embodiment, see Figure 4 , Figure 4 A reverse leakage-proof switched capacitor voltage converter is provided in an embodiment of the present application, such as Figure 4As shown, for any target switch (for example, Q6 or Q11):

[0062] The common end of the first switch circuit 200 is electrically connected to the anode of the body diode of the target switch tube (Q6 or Q11), the first end of the first switch circuit 200 is grounded, and the second end of the first switch circuit 200 is electrically connected to the first end of the target switch tube (Q6 or Q11).

[0063] The common end of the second switch circuit 300 is electrically connected to the control end of the target switch tube (Q6 or Q11), the first end of the second switch circuit 300 is grounded, and the second end of the second switch circuit 300 is electrically connected to the driving voltage end DRV.

[0064] The driving voltage terminal DRV is used to provide voltage for the control terminal of the target switch tube. In actual project applications, the voltage range of the driving voltage terminal DRV is usually set to: Vout~Vout+5V. The voltage of the driving voltage terminal DRV is controlled by the logic control circuit to switch between Vout and Vout+5V to achieve control of the on or off state of the target switch tube. Those skilled in the art can understand that when the voltage of the driving voltage terminal DRV is greater than Vout+Vth, the target switch tube will be turned on, where Vth is the switching threshold voltage between the gate and the source of the target switch tube. Usually, Vth is less than 5V. For example, when the voltage of the driving voltage terminal DRV is Vout, since the source voltage of the target switch tube is Vout, the target switch tube is turned off at this time; when the voltage of the driving voltage terminal DRV is Vout+Vth, since the source voltage of the target switch tube is Vout, the target switch tube is turned on at this time.

[0065] In one possible embodiment, see Figure 4 When the switched capacitor voltage converter is in working state, the logic control circuit 100 is used to control the first switch circuit 200 so that the anodes of the body diodes of the first target switch tube and the second target switch tube are both connected to the first end of the target switch tube; and control the second switch circuit 300 so that the control ends of the first target switch tube and the second target switch tube are both connected to the driving voltage end DRV, wherein the driving voltage end DRV is connected to the logic control circuit 100.

[0066] The reverse leakage protection switched capacitor voltage converter in the present application is in a non-working state, and the input voltage connected to the input voltage terminal is lower than the output voltage output by the output voltage terminal, and the absolute value of the difference between the input voltage and the output voltage is greater than a preset threshold value, and the reverse leakage protection operation is performed. Therefore, when the switched capacitor voltage converter is in a working state, the anodes of the body diodes of the first target switch tube and the second target switch tube do not need to be grounded, and the control ends of the first target switch tube and the second target switch tube do not need to be grounded.

[0067] In one possible embodiment, see Figure 4 The switched capacitor voltage conversion circuit 400 includes: a first switch tube Q1, a second switch tube Q2, a third switch tube Q3, a fourth switch tube Q4, a fifth switch tube Q5, a sixth switch tube Q6, a seventh switch tube Q7, an eighth switch tube Q8, a ninth switch tube Q9, a tenth switch tube Q10, an eleventh switch tube Q11, a twelfth switch tube Q12, a thirteenth switch tube Q13, a fourteenth switch tube Q14, a fifteenth switch tube Q15, a sixteenth switch tube Q16, a first capacitor CF1A, a second capacitor CF2A, a third capacitor CF1B, a fourth capacitor CF2B, a fifth capacitor COUT1, and a sixth capacitor COUT2.

[0068] The first end of the first switch tube Q1 is electrically connected to the first end of the first capacitor CF1A and the second end of the third switch tube Q3 , and the second end of the first switch tube Q1 is electrically connected to the second end of the sixteenth switch tube Q16 and the input voltage terminal IN.

[0069] A first end of the second switch tube Q2 is grounded, and a second end of the second switch tube Q2 is electrically connected to a second end of the first capacitor CF1A and a first end of the fourth switch tube Q4 respectively.

[0070] The first end of the third switch tube Q3 is electrically connected to the second end of the fifth switch tube Q5 , the first end of the fifth capacitor COUT1 , the second end of the twelfth switch tube Q12 , and the first end of the fourteenth switch tube Q14 , respectively.

[0071] The second end of the fourth switch tube Q4 is electrically connected to the first end of the twelfth switch tube Q12 , the second end of the sixth switch tube Q6 , and the first end of the second capacitor CF2A respectively.

[0072] The first end of the fifth switch tube Q5 is electrically connected to the second end of the thirteenth switch tube Q13 , the second end of the eleventh switch tube Q11 , and the first end of the fourth capacitor CF2B respectively.

[0073] The first end of the sixth switch tube Q6 is electrically connected to the second end of the seventh switch tube Q7 , the first end of the eleventh switch tube Q11 , the second end of the tenth switch tube Q10 , and the first end of the sixth capacitor COUT2 , respectively.

[0074] The first end of the seventh switch tube Q7 is electrically connected to the second end of the second capacitor CF2A and the second end of the eighth switch tube Q8 respectively.

[0075] A first terminal of the eighth switch tube Q8 is grounded.

[0076] A first end of the ninth switch tube Q9 is grounded, and a second end of the ninth switch tube Q9 is electrically connected to a first end of the tenth switch tube Q10 and a second end of the fourth capacitor CF2B respectively.

[0077] The first end of the thirteenth switch tube Q13 is electrically connected to the second end of the third capacitor CF1B and the second end of the fifteenth switch tube Q15 respectively.

[0078] The second end of the fourteenth switch tube Q14 is electrically connected to the first end of the third capacitor CF1B and the first end of the sixteenth switch tube Q16 respectively.

[0079] A first end of the fifteenth switch tube Q15 is grounded, a second end of the fifth capacitor COUT1 is grounded, and a second end of the sixth capacitor COUT2 is grounded.

[0080] Control ends of the first switch tube Q1, the second switch tube Q2, the third switch tube Q3, the fourth switch tube Q4, the fifth switch tube Q5, the sixth switch tube Q6, the seventh switch tube Q7, the eighth switch tube Q8, the ninth switch tube Q9, the tenth switch tube Q10, the eleventh switch tube Q11, the twelfth switch tube Q12, the thirteenth switch tube Q13, the fourteenth switch tube Q14, the fifteenth switch tube Q15 and the sixteenth switch tube Q16 are all electrically connected to the logic control circuit 100.

[0081] In one possible embodiment, see Figure 4 The first leakage path includes: the first switch tube Q1, the third switch tube Q3, the fifth switch tube Q5 and the eleventh switch tube Q11, and the second leakage path includes: the sixth switch tube Q6, the twelfth switch tube Q12, the fourteenth switch tube Q14 and the sixteenth switch tube Q16.

[0082] See also Figure 4 The switch tubes involved in the leakage path from the output voltage terminal OUT of the switched capacitor voltage converter to the input voltage terminal IN are: the first switch tube Q1, the third switch tube Q3, the fifth switch tube Q5, the eleventh switch tube Q11, the sixth switch tube Q6, the twelfth switch tube Q12, the fourteenth switch tube Q14 and the sixteenth switch tube Q16. The above-mentioned switch tubes can be divided into a first leakage path and a second leakage path. The output voltage terminal OUT of the switched capacitor voltage converter to the input voltage terminal IN can leak through the first leakage path or through the second leakage path.

[0083] In one possible embodiment, see Figure 4 The first leakage branch includes: a first switch tube Q1 and a third switch tube Q3, the second leakage branch includes: a fifth switch tube Q5 and an eleventh switch tube Q11, the third leakage branch includes: a fourteenth switch tube Q14 and a sixteenth switch tube Q16, and the fourth leakage branch includes: a sixth switch tube Q6 and a twelfth switch tube Q12.

[0084] Figure 4The circuit includes two output terminals, namely, an output voltage terminal OUT and an intermediate voltage terminal VO1, which are used to output voltages Vout and Vmid respectively. With the intermediate voltage terminal VO1 as the intermediate node, the first leakage path can be divided into a first leakage branch and a second leakage branch, and the second leakage path can be divided into a third leakage branch and a fourth leakage branch.

[0085] See also Figure 4 The topology of the switched capacitor voltage converter that prevents reverse leakage. In order to effectively prevent reverse leakage of the switched capacitor voltage converter, it is necessary to cut off all leakage paths from the output voltage terminal OUT to the input voltage terminal IN, that is, it is necessary to cut off the first leakage path and the second leakage path. Therefore, at least two switching tubes need to be selected, and the original electrical connection relationship between the body diode and the control terminal of the switching tube is cut off and pulled down to the ground, so that the first leakage path and the second leakage path can be completely cut off to prevent the occurrence of reverse leakage.

[0086] Therefore, when selecting the first target switch tube and the second target switch tube, the first target switch tube can be any switch tube in the first leakage branch, and the second target switch tube can be any switch tube in the third leakage branch, or the first target switch tube can be any switch tube in the second leakage branch, and the second target switch tube can be any switch tube in the fourth leakage branch. The following lists 8 selection combinations of the first target switch tube and the second target switch tube: Combination 1, the first target switch tube and the second target switch tube are: Q1 and Q16; Combination 2, the first target switch tube and the second target switch tube are: Q1 and Q14; Combination 3, the first target switch tube and the second target switch tube are: Q3 and Q16; Combination 4, the first target switch tube and the second target switch tube are: Q3 and Q14; Combination 5, the first target switch tube and the second target switch tube are: Q5 and Q12; Combination 6, the first target switch tube and the second target switch tube are: Q5 and Q6; Combination 7, the first target switch tube and the second target switch tube are: Q11 and Q12; Combination 8, the first target switch tube and the second target switch tube are: Q11 and Q6. In order to facilitate and clearly introduce the working principle of the circuit, Figure 4 In the figure, only combination 8 (the first target switch tube and the second target switch tube are: Q11 and Q6) is taken as an example to draw the electrical connection relationship of the relevant circuits, and the electrical connection relationship of all combinations is not drawn. It can be understood that the electrical connection relationship of other combinations is the same as the connection relationship of combination 8.

[0087] In a possible embodiment, the preset threshold is a minimum value of a sum of four times the forward conduction threshold of the body diode and the conduction thresholds of four switch tubes on the leakage path.

[0088] See also Figure 4The leakage path from the output voltage terminal OUT to the input voltage terminal IN of the switched capacitor voltage converter includes two leakage paths, each leakage path includes four switch tubes, and reverse leakage from the output voltage terminal OUT to the input voltage terminal IN can leak through the body diodes of the four switch tubes or through the channels of the four switch tubes. Specifically, when the absolute value of the difference between the input voltage and the output voltage is greater than 4 times the forward conduction threshold of the body diode, leakage can occur through the body diodes of the four switch tubes; when the absolute value of the difference between the input voltage and the output voltage is greater than the sum of the conduction thresholds of the four switch tubes, leakage can occur through the channels of the four switch tubes. The occurrence of reverse leakage depends on the minimum value of 4 times the forward conduction threshold of the body diode and the sum of the conduction thresholds of the four switches on the leakage path, that is, when the preset threshold reaches the minimum value of 4 times the forward conduction threshold of the body diode and the sum of the conduction thresholds of the four switches on the leakage path, reverse leakage from the output voltage terminal OUT to the input voltage terminal IN will occur, and a logic control circuit is required to control the target switch tube to cut off the leakage path of the body diode and the channel of the switch tube, so that the leakage path from the output voltage terminal OUT to the input voltage terminal IN is completely cut off, thereby preventing reverse leakage of the switched capacitor voltage converter.

[0089] In a possible embodiment, the first switch tube Q1, the second switch tube Q2, the third switch tube Q3, the fourth switch tube Q4, the fifth switch tube Q5, the sixth switch tube Q6, the seventh switch tube Q7, the eighth switch tube Q8, the ninth switch tube Q9, the tenth switch tube Q10, the eleventh switch tube Q11, the twelfth switch tube Q12, the thirteenth switch tube Q13, the fourteenth switch tube Q14, the fifteenth switch tube Q15 and the sixteenth switch tube Q16 are all N-type switch tubes.

[0090] In the embodiment of the present application, the first switch tube Q1, the second switch tube Q2, the third switch tube Q3, the fourth switch tube Q4, the fifth switch tube Q5, the sixth switch tube Q6, the seventh switch tube Q7, the eighth switch tube Q8, the ninth switch tube Q9, the tenth switch tube Q10, the eleventh switch tube Q11, the twelfth switch tube Q12, the thirteenth switch tube Q13, the fourteenth switch tube Q14, the fifteenth switch tube Q15 and the sixteenth switch tube Q16 can all be N-type field effect transistors, wherein the control end of the first switch tube Q1, the second switch tube Q2, the third switch tube Q3, the fourth switch tube Q4, the fifth switch tube Q5, the sixth switch tube Q6, the seventh switch tube Q7, the eighth switch tube Q8, the ninth switch tube Q9, the tenth switch tube Q10, the eleventh switch tube Q11, the twelfth switch tube Q12, the thirteenth switch tube Q13, the fourteenth switch tube Q14, the fifteenth switch tube Q15 and the sixteenth switch tube Q16 refers to the gate of the field effect transistor. the first end of the first switch tube Q1, the second switch tube Q2, the third switch tube Q3, the fourth switch tube Q4, the fifth switch tube Q5, the sixth switch tube Q6, the seventh switch tube Q7, the eighth switch tube Q8, the ninth switch tube Q9, the tenth switch tube Q10, the eleventh switch tube Q11, the twelfth switch tube Q12, the thirteenth switch tube Q13, the fourteenth switch tube Q14, the fifteenth switch tube Q15 and the sixteenth switch tube Q16 refers to the source of the field effect transistor; correspondingly, the second end of the first switch tube Q1, the second switch tube Q2, the third switch tube Q3, the fourth switch tube Q4, the fifth switch tube Q5, the sixth switch tube Q6, the seventh switch tube Q7, the eighth switch tube Q8, the ninth switch tube Q9, the tenth switch tube Q10, the eleventh switch tube Q11, the twelfth switch tube Q12, the thirteenth switch tube Q13, the fourteenth switch tube Q14, the fifteenth switch tube Q15 and the sixteenth switch tube Q16 refers to the drain of the field effect transistor.

[0091] See also Figure 4, taking combination 8 as an example, when the switched capacitor voltage converter is in a non-operating state, at this time, the input voltage Vin connected to the input voltage terminal IN is lower than the output voltage Vout outputted by the output voltage terminal OUT, and the input voltage Vin is lower than the output voltage Vout, and the difference between the two reaches the minimum value of the sum of the forward conduction threshold of the body diode 4 times and the conduction threshold of the four switch tubes on the leakage path (that is, when the absolute value of the difference between the input voltage and the output voltage is greater than the preset threshold): the anode of the body diode of the switch tube Q11 and the switch tube Q6 is controlled by the logic control circuit to be disconnected from the output voltage terminal OUT and connected to the ground, thereby cutting off the path of leakage through the body diode of the switch tube; and the gate of the switch tube Q11 and the switch tube Q6 is controlled to be disconnected from the driving voltage terminal and connected to the ground, thereby cutting off the path of reverse leakage through the channel of the switch tube. By cutting off the path of leakage of the body diode and the channel of the switch tube, the leakage path from the output voltage terminal OUT to the input voltage terminal IN is completely cut off, thereby preventing reverse leakage of the switched capacitor voltage converter. Since there is no need to introduce additional power tubes in this application, the chip area is reduced, the cost is reduced, and the charging efficiency is improved.

[0092] An embodiment of the present application also provides a chip, including: the above-mentioned switched capacitor voltage converter.

[0093] An embodiment of the present application also provides an electronic device, including: the above-mentioned chip.

[0094] Finally, it should be noted that the above embodiments are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto, and any changes or substitutions within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A reverse leakage-proof switched capacitor voltage converter, characterized in that: The switched capacitor voltage converter comprises: a logic control circuit, a first switch circuit, a second switch circuit, and a switched capacitor voltage conversion circuit, wherein the switched capacitor voltage conversion circuit comprises an input voltage terminal, an output voltage terminal, a first leakage path and a second leakage path, wherein the first leakage path comprises a first leakage branch and a second leakage branch, wherein the second leakage path comprises a third leakage branch and a fourth leakage branch, wherein the first leakage branch, the second leakage branch, the third leakage branch, and the fourth leakage branch each comprise two switch tubes; When the switched capacitor voltage converter is in a non-operating state, and the input voltage connected to the input voltage terminal is lower than the output voltage output by the output voltage terminal, and the absolute value of the difference between the input voltage and the output voltage is greater than a preset threshold: The logic control circuit is used to control the first switch circuit so that the anodes of the body diodes of the first target switch tube and the second target switch tube are both connected to the ground; and to control the second switch circuit so that the control ends of the first target switch tube and the second target switch tube are both connected to the ground; wherein the first target switch tube is any one of the switch tubes in the first leakage branch, and the second target switch tube is any one of the switch tubes in the third leakage branch, or the first target switch tube is any one of the switch tubes in the second leakage branch, and the second target switch tube is any one of the switch tubes in the fourth leakage branch.

2. The switched capacitor voltage converter according to claim 1, wherein: For any of the target switches: The common end of the first switch circuit is electrically connected to the anode of the body diode of the target switch tube, the first end of the first switch circuit is grounded, and the second end of the first switch circuit is electrically connected to the first end of the target switch tube; The common end of the second switch circuit is electrically connected to the control end of the target switch tube, the first end of the second switch circuit is grounded, and the second end of the second switch circuit is electrically connected to the driving voltage end.

3. The switched capacitor voltage converter according to claim 1, wherein: When the switched capacitor voltage converter is in an operating state, the logic control circuit is used to control the first switch circuit so that the anodes of the body diodes of the first target switch tube and the second target switch tube are both connected to the first end of the target switch tube; and control the second switch circuit so that the control ends of the first target switch tube and the second target switch tube are both connected to the driving voltage end, wherein the driving voltage end is electrically connected to the logic control circuit.

4. The switched capacitor voltage converter according to claim 1, wherein: The switch capacitor voltage conversion circuit includes: a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a fifth switch tube, a sixth switch tube, a seventh switch tube, an eighth switch tube, a ninth switch tube, a tenth switch tube, an eleventh switch tube, a twelfth switch tube, a thirteenth switch tube, a fourteenth switch tube, a fifteenth switch tube, a sixteenth switch tube, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, and a sixth capacitor; The first end of the first switch tube is electrically connected to the first end of the first capacitor and the second end of the third switch tube respectively, and the second end of the first switch tube is electrically connected to the second end of the sixteenth switch tube and the input voltage end respectively; The first end of the second switch tube is grounded, and the second end of the second switch tube is electrically connected to the second end of the first capacitor and the first end of the fourth switch tube respectively; The first end of the third switch tube is electrically connected to the second end of the fifth switch tube, the first end of the fifth capacitor, the second end of the twelfth switch tube and the first end of the fourteenth switch tube respectively; The second end of the fourth switch tube is electrically connected to the first end of the twelfth switch tube, the second end of the sixth switch tube, and the first end of the second capacitor respectively; The first end of the fifth switch tube is electrically connected to the second end of the thirteenth switch tube, the second end of the eleventh switch tube, and the first end of the fourth capacitor respectively; The first end of the sixth switch tube is electrically connected to the second end of the seventh switch tube, the first end of the eleventh switch tube, the second end of the tenth switch tube and the first end of the sixth capacitor respectively; The first end of the seventh switch tube is electrically connected to the second end of the second capacitor and the second end of the eighth switch tube respectively; The first end of the eighth switch tube is grounded; The first end of the ninth switch tube is grounded, and the second end of the ninth switch tube is electrically connected to the first end of the tenth switch tube and the second end of the fourth capacitor respectively; The first end of the thirteenth switch tube is electrically connected to the second end of the third capacitor and the second end of the fifteenth switch tube respectively; The second end of the fourteenth switch tube is electrically connected to the first end of the third capacitor and the first end of the sixteenth switch tube respectively; The first end of the fifteenth switch is grounded, the second end of the fifth capacitor is grounded, and the second end of the sixth capacitor is grounded; Control ends of the first switch tube, the second switch tube, the third switch tube, the fourth switch tube, the fifth switch tube, the sixth switch tube, the seventh switch tube, the eighth switch tube, the ninth switch tube, the tenth switch tube, the eleventh switch tube, the twelfth switch tube, the thirteenth switch tube, the fourteenth switch tube, the fifteenth switch tube and the sixteenth switch tube are all electrically connected to the logic control circuit.

5. The switched capacitor voltage converter according to claim 4, wherein: The first leakage path includes: the first switch tube, the third switch tube, the fifth switch tube and the eleventh switch tube, and the second leakage path includes: the sixth switch tube, the twelfth switch tube, the fourteenth switch tube and the sixteenth switch tube.

6. The switched capacitor voltage converter according to claim 5, wherein: The first leakage branch includes: the first switch tube and the third switch tube, the second leakage branch includes: the fifth switch tube and the eleventh switch tube, the third leakage branch includes: the fourteenth switch tube and the sixteenth switch tube, and the fourth leakage branch includes: the sixth switch tube and the twelfth switch tube.

7. The switched capacitor voltage converter according to claim 1, wherein: The preset threshold is the minimum value of the sum of four times the forward conduction threshold of the body diode and the conduction thresholds of the four switch tubes on the leakage path.

8. The switched capacitor voltage converter according to claim 4, wherein: The first switch tube, the second switch tube, the third switch tube, the fourth switch tube, the fifth switch tube, the sixth switch tube, the seventh switch tube, the eighth switch tube, the ninth switch tube, the tenth switch tube, the eleventh switch tube, the twelfth switch tube, the thirteenth switch tube, the fourteenth switch tube, the fifteenth switch tube and the sixteenth switch tube are all N-type switch tubes.

9. A chip, characterized in that: include: A switched capacitor voltage converter as claimed in any one of claims 1 to 8.

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

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