Reconfigurable wide load range switched capacitor dc-dc converter and control method thereof

Abstract

The application discloses a reconfigurable wide load range switched capacitor DC-DC converter and a control method thereof. For the DC-DC converter, a flying capacitor with a low capacitance value is selected at light load to reduce the parasitic capacitance loss of the flying capacitor lower stage plate, so that high efficiency is realized, and a flying capacitor with a high capacitance value is selected at heavy load to realize a wide load range. Meanwhile, a double clock circuit is adopted, a low-frequency clock signal is adopted at light load, so that high efficiency is realized, and a high-frequency clock signal is selected at heavy load to realize a wide load range.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of switched-capacitor DC-DC converter, and particularly relates to a reconfigurable wide load range switched-capacitor DC-DC converter and a control method thereof. BACKGROUND

[0002] The switched-capacitor DC-DC converter can provide high efficiency, low power consumption, wide input voltage range, small size, high integration and fast dynamic response, and can provide stable, efficient and reliable power supply for Internet of Things devices and meet the specific power management requirements. The switched-capacitor DC-DC converter is mainly composed of a switched-capacitor topology structure and a feedback loop. The series-parallel structure can realize different conversion ratios according to the connection mode of the switch, thereby improving the efficiency. The switched-capacitor DC-DC converter has various topologies, including Dickson structure, ladder structure, Fibonacci structure, series-parallel structure and the like. Although the structures are different, the basic working principles are similar. Each structure has its own advantages, such as the Dickson structure and the ladder structure which have good adjustability, and the series-parallel structure which has strong load capacity. The above characteristics have attracted more and more attention in portable devices and energy harvesting systems.

[0003] The patent with publication number CN108539981A discloses that the input port of the switched-capacitor DC-DC converter and the switching converter is connected in series or parallel, and the output port is connected in another way in series or parallel to improve the efficiency of the circuit system. The switched-capacitor DC-DC converter adopts an open-loop design, and the switching converter adopts a closed-loop design. The switched-capacitor DC-DC converter and the switching converter simultaneously deliver power to the output to improve the system efficiency. In order to realize the electrical isolation of the switched-capacitor DC-DC converter and the switching converter, an isolation capacitor is used to isolate the input port and the output port, which increases the chip area and also increases the economic cost. At the same time, the switching converter needs to control the inductor L, so that high integration cannot be realized.

[0004] The authorized patent with publication number CN108923643B discloses a reconfigurable boost charge pump without threshold voltage loss. The switch tube group and the floating capacitor group are used to realize the charge pump with different multiplication. The problem of serious device waste in realizing different multiplication of the charge pump is solved, and the clock supercharging circuit is used. The threshold voltage loss of the power tube in the switch capacitor DC-DC converter is reduced through the level converter switching in two different working states. In the process of realizing reconfiguration of the power stage circuit, although the level converter can eliminate the threshold voltage drop of the switch capacitor DC-DC converter, when the output voltage swing of the level converter is large, the high energy loss will still be introduced on the MOS gate capacitor due to the large voltage swing. While eliminating the threshold voltage drop and improving the efficiency, the additional energy loss is introduced. The efficiency improvement is not as obvious as the ideal case. SUMMARY

[0005] In view of the deficiencies in the prior art, the purpose of the present application is to provide a reconfigurable wide load range switch capacitor DC-DC converter and its control method, which can improve the overall efficiency of the converter system.

[0006] The first aspect of the present disclosure provides a reconfigurable wide load range switch capacitor DC-DC converter, comprising:

[0007] an input end configured to receive an input voltage;

[0008] an output end configured to deliver an output voltage;

[0009] a switch body arranged between each branch and module of the control circuit, the switch body being configured to change the ratio of the output voltage to the input voltage of the DC-DC converter by changing the working mode of the switch body to meet different load requirements;

[0010] a first flying capacitor body and a second flying capacitor body connected in series through a bootstrap switch, the first flying capacitor body and the second flying capacitor body are both gated capacitor arrays, and the gated capacitor array comprises one or more gated capacitors;

[0011] an output end capacitor arranged between the output end and the ground.

[0012] Optionally, the switch body comprises a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a seventh switch, an eighth switch, a ninth switch, a tenth switch and an eleventh switch.

[0013] The first switch and the fifth switch are electrically connected with the input end, and the first switch is connected in parallel with the fifth switch; the third switch and the seventh switch are electrically connected with the ground end; the second switch, the fourth switch, the sixth switch and the eighth switch are electrically connected with the output end.

[0014] The ninth switch is configured to connect the first flying capacitor body and the second flying capacitor body in series; an input end of the first flying capacitor body is electrically connected with the tenth switch, and an output end of the second flying capacitor body is electrically connected with an output end of the eleventh switch.

[0015] Optionally, the working mode of the switch body includes a first working mode, a second working mode and a third working mode; in the first working mode, the ratio of the output voltage to the input voltage of the DC-DC converter is 1; in the second working mode, the ratio of the output voltage to the input voltage of the DC-DC converter is 2 / 3; in the third working mode, the ratio of the output voltage to the input voltage of the DC-DC converter is 1 / 2.

[0016] Optionally, the first working mode is configured as:

[0017] The third switch is kept constant conduction;

[0018] When the first switch and the third switch are turned on, the first flying capacitor body is charged;

[0019] When the second switch and the third switch are turned on, the first flying capacitor body charges the output capacitor.

[0020] Optionally, the second working mode is configured as:

[0021] When the first switch, the fourth switch, the fifth switch and the eighth switch are turned on, the first flying capacitor body and the second flying capacitor body are charged at the same time;

[0022] When the second switch, the fourth switch and the eighth switch are turned on, the first flying capacitor body and the second flying capacitor body charge the output capacitor at the same time.

[0023] Optionally, the third working mode is configured as:

[0024] When the first switch, the fourth switch, the fifth switch and the eighth switch are turned on, the first flying capacitor body and the second flying capacitor body are charged at the same time;

[0025] When the second switch, the third switch, the sixth switch and the seventh switch are turned on, the first flying capacitor body and the second flying capacitor body simultaneously charge the output end capacitor.

[0026] Optionally, the first flying capacitor body and the second flying capacitor body are configured to:

[0027] When the DC-DC converter is in a light load state, the first flying capacitor body and the second flying capacitor body both select a capacitor with a small capacitance value and a low frequency clock signal.

[0028] When the DC-DC converter is in a heavy load state, the first flying capacitor body and the second flying capacitor body both select a capacitor with a large capacitance value and a high frequency clock signal.

[0029] Optionally, the tenth switch and the eleventh switch are multi-path selection switches.

[0030] The second aspect of the present disclosure provides a control method applied in the reconfigurable wide load range switched capacitor DC-DC converter of the first aspect, the method comprising:

[0031] When the DC-DC converter is in a light load state, the first flying capacitor body and the second flying capacitor body are controlled to both select a capacitor with a small capacitance value and a low frequency clock signal; and

[0032] When the DC-DC converter is in a heavy load state, the first flying capacitor body and the second flying capacitor body are controlled to both select a capacitor with a large capacitance value and a high frequency clock signal.

[0033] The third aspect of the present disclosure provides a reconfigurable wide load range switched capacitor DC-DC converter system, the system comprising:

[0034] The switched capacitor DC-DC converter of the first aspect;

[0035] a processing unit; and

[0036] a non-transitory readable storage medium storing instructions which, when executed by the processing unit, cause the processing unit to perform the following steps:

[0037] When the DC-DC converter is in a light load state, the first flying capacitor body and the second flying capacitor body are controlled to both select a capacitor with a small capacitance value and a low frequency clock signal; and

[0038] When the DC-DC converter is in a heavy load state, the first flying capacitor main body and the second flying capacitor main body are controlled to select the capacitor with a large capacitance value, and the high-frequency clock signal is selected.

[0039] The above scheme has the following beneficial effects:

[0040] In the present disclosure, the reconfigurable technology and the frequency hopping technology in the switched capacitor DC-DC converter are innovatively combined. For the application in the light load condition, the switched capacitor DC-DC converter selects the flying capacitor with a small capacitance value and the clock signal with a low frequency, thereby improving the overall efficiency of the entire converter system.

[0041] Compared with the traditional structure, the flying capacitor with a selectable capacitance value is used. In the light load condition, the flying capacitor with a low capacitance value is selected to reduce the parasitic capacitance loss of the flying capacitor lower stage plate and achieve high efficiency. In the heavy load condition, the flying capacitor with a high capacitance value is selected to achieve a wide load range. The double clock circuit is used. In the light load condition, the low-frequency clock signal is used to achieve high efficiency. In the heavy load condition, the high-frequency clock signal is selected to achieve a wide load range. The reconfigurable series-parallel structure is used to adaptively select the 1x, 2 / 3x, 1 / 2x, and 1 / 3x four gain modes according to different input voltage ranges to achieve a wide input voltage range. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 The circuit structure schematic diagram of the DC-DC converter of the present application is shown.

[0043] Figure 2 The circuit principle schematic diagram of the reconfigurable step-down switched capacitor DC-DC converter of the present application is shown.

[0044] Figure 3 The circuit diagram of the pulse hopping modulation circuit of the present application is shown. DETAILED DESCRIPTION

[0045] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application will be described in further detail below with reference to the drawings. The described embodiments should not be regarded as limiting the present application. All other embodiments obtained by those skilled in the art without making creative efforts fall within the scope of protection of the present application.

[0046] In the following description, “some embodiments”, “examples” are related to a subset of all possible embodiments, but it can be understood that “some embodiments” and “examples” can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0047] In the following description, the terms "first", "second", "third", "fourth", "fifth", "sixth", "seventh", "eighth", and "ninth" are merely used to distinguish similar objects, and do not represent a specific order or sequence. It is understood that the "first", "second", "third", "fourth", "fifth", "sixth", "seventh", "eighth", and "ninth" can be interchanged in a specific order or sequence as permitted, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein.

[0048] In the embodiments of the present application, the term "module" or "unit" refers to a control program or a part of a control program with a predetermined function, and works together with other related parts to achieve a predetermined target, and can be implemented entirely or partially by using software, hardware (such as a processing circuit or a memory), or a combination thereof. Similarly, one processing unit (or multiple processing units or memories) can be used to implement one or more modules or units. In addition, each module or unit can be a part of an overall module or unit that includes the functions of the module or unit.

[0049] Unless otherwise defined, all technical and scientific terms used in the embodiments of the present application have the same meanings as commonly understood by one of ordinary skill in the art. For example, "flying capacitor" refers to a capacitor used for charging and discharging in a switched capacitor DC-DC converter, which can be one or more; "pulse skipping modulation" refers to a method used for loop modulation of a DC-DC converter, which is commonly used to reduce the power consumption of a switching power supply under low load conditions by skipping certain pulse periods to control the output voltage. The terms used in the embodiments of the present application are only for the purpose of describing the embodiments of the present application, and are not intended to limit the present application.

[0050] Figure 1 is a schematic circuit structure diagram of a direct current-direct current converter of a first embodiment of the present application. As shown in Figure 1 The reconfigurable wide load range switched capacitor DC-DC converter of the present embodiment includes MOS switch, bootstrap switch, first flying capacitor C1 and second flying capacitor C2, wherein the first flying capacitor C1 and the second flying capacitor C2 are a gated capacitor array, and the flying capacitors C1 and C2 select capacitors with small capacitance values under light load, and select capacitors with large capacitance values under heavy load. The first capacitor C1 and the second capacitor C2 are connected in series through the bootstrap switch S9.

[0051] Wherein the light load is relative to the full load, refers to in the load range of the circuit, the load rate is below 50% of the load. The load rate is above 80% is considered to be heavy load. To distinguish between light load and heavy load, can be determined by measuring the current, voltage, power and other parameters of the converter. Generally speaking, in the case of light load, the current and voltage of the converter are small, and the power is relatively small; in the case of heavy load, the current and voltage of the converter are large, and the power is relatively large.

[0052] The reconfigurable wide load range DC-DC converter of the embodiment can realize three voltage conversion ratios:

[0053] The first voltage conversion ratio

[0054] Wherein in the first working mode, MOS switch S1 and bootstrap switch S2 are controlled by clock signal, and MOS switch S3 is kept constant conduction. Wherein S1 and S3 are turned on, the first capacitor is charged, S2 and S3 are turned on, the first capacitor charges the output capacitor. So that the ratio of the output voltage Vout1 of the switched capacitor DC-DC converter to Vin1 is a fixed value, that is, the output voltage Vout1 of the switched capacitor converter and Vin1 satisfy the following relationship:

[0055]

[0056] Wherein one end of phase1 switch S1 in the first working mode is connected in series with Vin, and one end of switch S3 is connected in series with the ground end. Switches S1 and S3 are connected in series between Vin and Vout, and first capacitor C1 is connected in series at the middle end of switches S1 and S3. In the first working mode, one end of phase2 switch S3 is connected in series with the ground end, switches S2 and S3 are connected in series between the ground end and Vout, and first capacitor C1 is connected in series at the middle end of switches S2 and S3.

[0057] The second voltage conversion ratio

[0058] In the second working mode of the DC-DC converter of the embodiment, MOS switches S1, S5, S7, bootstrap switches S2, S4, S8, S9. Among them, S1, S4, S5, S8 are turned on, first capacitor C1 and second capacitor C2 are charged at the same time, S2, S4, S8 are turned on, first capacitor C1 and second capacitor C2 charge the output capacitor at the same time. So that the ratio of the output voltage Vout2 of the switched capacitor DC-DC converter to Vin2 is a fixed value, that is, the output voltage Vout2 of the switched capacitor converter and Vin2 satisfy the following relationship:

[0059]

[0060] In the second working mode, one end of phase 1 switch S1 and S5 is connected in series with Vin, S1 and S5 are connected in parallel, one end of S1 is connected in series with the first capacitor C1, and the other end of the first capacitor is connected in series with S4 to Vout. The other end of S5 is connected in series with the second capacitor C2, and the other end of the second capacitor is connected in series with S4 to Vout. One end of phase 2 switch S7 in the second working mode is connected in series with the ground, and the other end is connected in series with the second capacitor, and the other end of the second capacitor is connected in series with S9, and S9 is connected in series with the first capacitor C1, and the first capacitor C1 is connected in series with S2 to Vout.

[0061] Third voltage conversion ratio

[0062] In the third working mode of the DC-DC converter of the embodiment, MOS switches S1, S3, S5, S7, bootstrap switches S2, S4, S8. Among them, S1, S4, S5, S8 are turned on, the first capacitor C1 and the second capacitor C2 are charged at the same time, S2, S3, S6, S7 are turned on, and the first capacitor C1 and the second capacitor C2 are charged at the same time. The output capacitor. So that the ratio of the output voltage Vout3 of the switched capacitor DC-DC converter to Vin3 is a fixed value, that is, the output voltage Vout3 of the switched capacitor converter and Vin3 satisfy the following relationship:

[0063]

[0064] In the second working mode, one end of phase 1 switch S1 and S5 is connected in series with Vin, S1 and S5 are connected in parallel, one end of S1 is connected in series with the first capacitor C1, and the other end of the first capacitor is connected in series with S4 to Vout. The other end of S5 is connected in series with the second capacitor C2, and the other end of the second capacitor is connected in series with S4 to Vout. One end of phase 2 switch S3 and S7 in the second working mode is connected in series with the ground, and S3 and S7 are connected in parallel, one end of S3 is connected in series with the first capacitor C1, and the other end of the first capacitor is connected in series with S2 to Vout. The other end of S7 is connected in series with the second capacitor C2, and the other end of the second capacitor is connected in series with S6 to Vout.

[0065] As Figure 1 shown, optionally, the switched capacitor DC-DC converter can also achieve 1 / 3x according to design requirements through a logic circuit, while achieving four conversion ratios, further increasing the input voltage range.

[0066] Figure 2The application provides a reconfigurable step-down switch capacitor DC-DC converter circuit principle diagram, which comprises a gain selection circuit, a mode selection circuit, a clock circuit, a level converter and a logic control module. An input voltage is connected to three hysteresis comparators through three resistors, and a suitable voltage conversion ratio is selected by dividing different intervals to improve the system efficiency. The hysteresis comparators are used for preventing the gain jump module from continuously jumping when the input voltage swings around the interval point, so that the system is more stable. The output result is b3, b2 and b1. A clock signal is connected to the input end of the logic control module to form a 4-bit control signal for controlling nine switches of the switch capacitor DC-DC converter to generate different voltage conversion ratios. The output is connected to the input end of the dynamic comparator through a feedback resistor and compared with a reference voltage. When the feedback voltage is higher than the reference voltage, the PSM frequency modulation circuit is used to skip several periods until the feedback voltage is lower than the reference voltage. The mode selection circuit can select a light load clock signal when the load is light, and select a flying capacitor with a small capacitance value, and select a heavy load clock signal when the load is heavy, and select a flying capacitor with a large capacitance value.

[0067] Optionally, the loop control of the switch capacitor DC-DC converter is pulse skipping modulation technology, and the PWM+PSM control can be realized according to the size of the load current, so that the efficiency of the switch capacitor DC-DC converter is further improved.

[0068] Figure 3 The application provides a pulse skipping modulation circuit used in the first embodiment, wherein the output voltage Vout is connected to the positive end of a dynamic comparator, the negative end of the dynamic comparator is connected to a reference voltage, and the output end is connected to the input of an XOR gate. The OUTP and the output of the XOR gate are used as the inputs of an NAND gate, and the output signal is connected to the input of a D flip-flop. An EN enabling signal is generated through the D flip-flop, and the EN enabling signal and a clock signal are used as the input signals of an AND gate. The EN enabling signal is used for controlling whether the clock signal skips several pulses. The pulse skipping modulation circuit used in the first embodiment adjusts the pulse signal of the switch capacitor DC-DC converter to adjust the output voltage, realizes a stable output voltage, and realizes the reconfigurable switch capacitor DC-DC converter together with the gain selection module.

[0069] In combination Figure 1 The following examples are given.

[0070] Example 1: a reconfigurable wide load range switch capacitor DC-DC converter, comprising:

[0071] an input end configured to receive an input voltage;

[0072] an output end configured to deliver an output voltage;

[0073] A switch body is arranged between each branch and module of the control circuit, and the switch body is configured to change its working mode to make the ratio of the output voltage to the input voltage of the DC-DC converter meet different load requirements;

[0074] The first flying capacitor body and the second flying capacitor body are connected in series through a bootstrap switch, and the first flying capacitor body and the second flying capacitor body are both gated capacitor arrays, and the gated capacitor array includes one or more gated capacitors;

[0075] An output capacitor is arranged between the output terminal and the ground.

[0076] Example 2: The DC-DC converter according to example 1, the switch body includes a first switch S1, a second switch S2, a third switch S3, a fourth switch S4, a fifth switch S5, a sixth switch S6, a seventh switch S7, an eighth switch S8, a ninth switch S9, a tenth switch S10 and an eleventh switch S11;

[0077] The first switch S1 and the fifth switch S5 are both electrically connected to the input terminal, and the first switch S1 and the fifth switch S5 are connected in parallel; the third switch S3 and the seventh switch S7 are both electrically connected to the ground terminal; the second switch S2, the fourth switch S4, the sixth switch S6 and the eighth switch S8 are all electrically connected to the output terminal;

[0078] The ninth switch S9 is configured to connect the first flying capacitor body and the second flying capacitor body in series; the input terminal of the first flying capacitor body is electrically connected to the tenth switch S10, and the output terminal of the second flying capacitor body is electrically connected to the output terminal of the eleventh switch S11.

[0079] Example 3: The DC-DC converter according to example 2, the working mode of the switch body includes a first working mode, a second working mode and a third working mode; in the first working mode, the ratio of the output voltage to the input voltage of the DC-DC converter is 1; in the second working mode, the ratio of the output voltage to the input voltage of the DC-DC converter is 2 / 3; in the third working mode, the ratio of the output voltage to the input voltage of the DC-DC converter is 1 / 2.

[0080] Example 4: The DC-DC converter according to example 3, the first working mode is configured to:

[0081] The third switch S3 remains constant and is turned on;

[0082] When the first switch S1 and the third switch S3 are turned on, the first flying capacitor body is charged;

[0083] The first flying capacitor body charges the output capacitor when the second switch S2 and the third switch S3 are turned on.

[0084] Example 5: The DC-DC converter according to any one of examples 3 or 4, the second working mode is configured to:

[0085] The first flying capacitor body and the second flying capacitor body are simultaneously charged when the first switch S1, the fourth switch S4, the fifth switch S5 and the eighth switch S8 are turned on;

[0086] The first flying capacitor body and the second flying capacitor body simultaneously charge the output capacitor when the second switch S2, the fourth switch S4 and the eighth switch S8 are turned on.

[0087] Example 6: The DC-DC converter according to any one of examples 3-5, the third working mode is configured to:

[0088] The first flying capacitor body and the second flying capacitor body are simultaneously charged when the first switch S1, the fourth switch S4, the fifth switch S5 and the eighth switch S8 are turned on;

[0089] The first flying capacitor body and the second flying capacitor body simultaneously charge the output capacitor when the second switch S2, the third switch S3, the sixth switch S6 and the seventh switch S7 are turned on.

[0090] Example 7: The DC-DC converter according to any one of examples 1-6, the first flying capacitor body and the second flying capacitor body are configured to:

[0091] When the DC-DC converter is in a light load state, the first flying capacitor body and the second flying capacitor body both select a capacitor with a small capacitance value and a low frequency clock signal;

[0092] When the DC-DC converter is in a heavy load state, the first flying capacitor body and the second flying capacitor body both select a capacitor with a large capacitance value and a high frequency clock signal.

[0093] Example 8: The DC-DC converter according to example 2, the tenth switch S10 and the eleventh switch S11 are multipath selection switches. The first switch S1, the third switch S3, the fifth switch S5 and the seventh switch S7 are MOS switch tubes, and the second switch S2, the fourth switch S4, the sixth switch S6, the eighth switch S8 and the ninth switch S9 are bootstrap switches.

[0094] Example 9: A control method applied in the switched-capacitor DC-DC converter as claimed in any one of examples 1-8, the method comprising:

[0095] when the DC-DC converter is in a light load state, controlling the first flying capacitor body and the second flying capacitor body to select a capacitor with a small capacitance value and a low frequency clock signal; and

[0096] when the DC-DC converter is in a heavy load state, the first flying capacitor body and the second flying capacitor body select a capacitor with a large capacitance value and a high frequency clock signal.

[0097] Example 10: The method as claimed in example 9, further comprising:

[0098] keeping the third switch S3 constantly on;

[0099] controlling the first switch S1 and the third switch S3 to be on, charging the first flying capacitor body;

[0100] controlling the second switch S2 and the third switch S3 to be on, so that the first flying capacitor body charges the output capacitor; and

[0101] the ratio of the output voltage to the input voltage of the DC-DC converter is configured to be 1.

[0102] Example 11: The method as claimed in example 9, further comprising:

[0103] controlling the first switch S1, the fourth switch S4, the fifth switch S5 and the eighth switch S8 to be on, simultaneously charging the first flying capacitor body and the second flying capacitor body;

[0104] controlling the second switch S2, the fourth switch S4 and the eighth switch S8 to be on, so that the first flying capacitor body and the second flying capacitor body simultaneously charge the output capacitor; and

[0105] the ratio of the output voltage to the input voltage of the DC-DC converter is configured to be 2 / 3.

[0106] Example 12: The method as claimed in example 9, further comprising:

[0107] controlling the first switch S1, the fourth switch S4, the fifth switch S5 and the eighth switch S8 to be on, simultaneously charging the first flying capacitor body and the second flying capacitor body;

[0108] controlling the second switch S2, the third switch S3, the sixth switch S6, and the seventh switch S7 to be conductive such that the first flying capacitor body and the second flying capacitor body simultaneously charge the output terminal capacitor; and

[0109] a ratio of an output voltage to an input voltage of the DC-DC converter is configured to be 1 / 2.

[0110] Example 13: A switched capacitor DC-DC converter system, the system comprising:

[0111] The switched capacitor DC-DC converter of any one of examples 1-8;

[0112] a processing unit; and

[0113] a non-transitory readable storage medium having stored instructions that, when executed by the processing unit, cause the processing unit to perform the following steps:

[0114] when the DC-DC converter is in a light load state, controlling the first flying capacitor body and the second flying capacitor body to select a capacitor with a small capacitance value; and

[0115] when the DC-DC converter is in a heavy load state, the first flying capacitor body and the second flying capacitor body select a capacitor with a large capacitance value.

[0116] Example 14: The system of example 13, wherein the steps further comprise:

[0117] maintaining the third switch S3 constantly conductive;

[0118] controlling the first switch S1 and the third switch S3 to be conductive to charge the first flying capacitor body;

[0119] controlling the second switch S2 and the third switch S3 to be conductive such that the first flying capacitor body charges the output terminal capacitor; and

[0120] a ratio of an output voltage to an input voltage of the DC-DC converter is configured to be 1.

[0121] Example 15: The system of example 13, wherein the steps further comprise:

[0122] controlling the first switch S1, the fourth switch S4, the fifth switch S5, and the eighth switch S8 to be conductive to simultaneously charge the first flying capacitor body and the second flying capacitor body;

[0123] controlling the second switch S2, the fourth switch S4, and the eighth switch S8 to be conductive such that the first flying capacitor body and the second flying capacitor body simultaneously charge the output capacitor; and

[0124] The ratio of the output voltage to the input voltage of the DC-DC converter is configured to be 2 / 3.

[0125] Example 16: The system of example 13, wherein the steps further comprise:

[0126] controlling the first switch S1, the fourth switch S4, the fifth switch S5, and the eighth switch S8 to be conductive to simultaneously charge the first flying capacitor body and the second flying capacitor body;

[0127] controlling the second switch S2, the third switch S3, the sixth switch S6, and the seventh switch S7 to be conductive such that the first flying capacitor body and the second flying capacitor body simultaneously charge the output capacitor; and

[0128] The ratio of the output voltage to the input voltage of the DC-DC converter is configured to be 1 / 2.

[0129] Example 17: The system of example 13, the steps further comprising:

[0130] The ratio of the output voltage to the input voltage of the DC-DC converter is configured to be 1 / 3.

[0131] Example 18: The system of example 13, wherein

[0132] The loop control of the switched-capacitor DC-DC converter is a pulse skip modulation technique that implements PWM+PSM control according to the size of the load current.

[0133] Example 19: The system of example 13, wherein

[0134] The processing unit of the switched-capacitor DC-DC converter includes one or more of a gain selection circuit, a mode selection circuit, a clock circuit, a level shifter, a hysteresis comparator, and a logic control module.

[0135] References to features, advantages, benefits, or similar language throughout the foregoing description do not imply that all features and advantages achievable with this technology should be or are present in any single embodiment of this technology. Rather, references to features and advantages are understood to indicate that a particular feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of this technology. Therefore, the discussion of features and advantages throughout this specification, as well as similar language, may refer to, but are not necessarily, the same embodiment. Furthermore, the features, advantages, and characteristics described in this technology can be combined in one or more embodiments in any suitable manner. Those skilled in the art will recognize that this technology can be practiced without one or more particular features or advantages in a particular embodiment. In other instances, additional features and advantages may be identified in certain embodiments that may not be present in all embodiments of this technology.

[0136] The detailed description of the examples and embodiments of this technology above is not intended to be exhaustive or to limit the technology to the precise forms disclosed above. Although specific examples of the technology have been described above for illustrative purposes, as those skilled in the art will recognize, various equivalent modifications can be made within the scope of the invention. The teachings of the technology provided herein can be applied to other systems, not necessarily those described above. Elements and behaviors of the various examples described above can be combined to provide further implementations of the technology. Some alternative implementations of the technology may include not only additional elements of those implementations described above, but may also include fewer elements. Furthermore, any specific figures mentioned herein are merely examples: alternative implementations may employ different values ​​or ranges.

[0137] As will be understood from the foregoing, specific embodiments of the present technology have been described herein for illustrative purposes, but various modifications may be made without departing from the spirit and scope of the various embodiments of the present technology. Furthermore, while various advantages associated with certain embodiments of the present technology have been described above in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments must exhibit such advantages to fall within the scope of the present technology. Therefore, the present technology is not limited other than by the appended claims.

[0138] Although certain aspects of the present technology are presented below in the form of certain claims, the applicant contemplates multiple aspects of the present technology in any number of claims. Therefore, the applicant reserves the right to seek additional claims after the filing of this application, in the form of such additional claims in this application or a continuation thereof.

Claims

1. A reconfigurable wide load range switched-capacitor DC-DC converter, characterized by, include: The input terminal is configured to receive input voltage; The output terminal is configured to transmit the output voltage; A switch body is disposed between various branches and modules of the control circuit. The switch body is configured to change its operating mode so that the ratio of the output voltage to the input voltage of the DC-DC converter meets different load requirements. A first flying capacitor body and a second flying capacitor body are connected in series via a bootstrap switch. Both the first flying capacitor body and the second flying capacitor body are gating capacitor arrays, and the gating capacitor array includes one or more gating capacitors. The output capacitor is placed between the output terminal and ground. The input voltage is connected to three hysteresis comparators via three resistors, which are used to select a suitable voltage conversion ratio by dividing different intervals; The hysteresis comparator is configured to prevent the control gain switching module from continuously switching when the input voltage swings around the approximate point of the interval. The output result is three signals, which are connected to the input of the logic control module along with the clock signal to form a four-bit control signal to control the various switches of the switched capacitor DC-DC converter to produce different voltage conversion ratios. The output is connected to the input of a dynamic comparator via a feedback resistor and compared with a reference voltage. Through a PSM frequency modulation circuit, when the feedback voltage is higher than the reference voltage, the cycle is skipped as needed until the feedback voltage is lower than the reference voltage. The output voltage is connected to the positive terminal of the dynamic comparator, the negative terminal of the dynamic comparator is connected to the reference voltage, and the output terminal is connected to the input of the XOR gate. The output terminal and the output of the XOR gate are used together as the input of the NAND gate. The output of the NAND gate is connected to the input of the D flip-flop. An enable signal is generated by the D flip-flop and used together with the clock signal as the input signal of the AND gate. The enable signal is used to control the clock signal to jump several pulses.

2. The reconfigurable wide load range switched capacitor DC-DC converter according to claim 1, characterized in that, The switch body includes a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a seventh switch, an eighth switch, a ninth switch, a tenth switch, and an eleventh switch; The first switch and the fifth switch are both electrically connected to the input terminal, and the first switch and the fifth switch are connected in parallel; the third switch and the seventh switch are both electrically connected to the ground terminal; the second switch, the fourth switch, the sixth switch and the eighth switch are all electrically connected to the output terminal. The ninth switch is configured to connect the first flying capacitor body and the second flying capacitor body in series; the input terminal of the first flying capacitor body is electrically connected to the tenth switch, and the output terminal of the second flying capacitor body is electrically connected to the output terminal of the eleventh switch.

3. The reconfigurable wide load range switched-capacitor DC-DC converter of claim 2, wherein, The operating modes of the switch body include a first operating mode, a second operating mode, and a third operating mode; in the first operating mode, the ratio of the output voltage to the input voltage of the DC-DC converter is 1. In the second working mode, a ratio of an output voltage to an input voltage of the DC-DC converter is 2 / 3; In the third working mode, a ratio of an output voltage to an input voltage of the DC-DC converter is 1 / 2.

4. The reconfigurable wide load range switched-capacitor DC-DC converter of claim 3, wherein, The first working mode is configured to: The third switch is kept constant conduction; When the first switch and the third switch are turned on, the first flying capacitor body is charged; When the second switch and the third switch are turned on, the first flying capacitor body charges the output terminal capacitor.

5. The reconfigurable wide load range switched-capacitor DC-DC converter of claim 3, wherein, The second working mode is configured to: When the first switch, the fourth switch, the fifth switch and the eighth switch are turned on, the first flying capacitor body and the second flying capacitor body are simultaneously charged; When the second switch, the fourth switch and the eighth switch are turned on, the first flying capacitor body and the second flying capacitor body simultaneously charge the output terminal capacitor.

6. The reconfigurable wide load range switched-capacitor DC-DC converter of claim 3, wherein, The third working mode is configured to: When the first switch, the fourth switch, the fifth switch and the eighth switch are turned on, the first flying capacitor body and the second flying capacitor body are simultaneously charged; When the second switch, the third switch, the sixth switch and the seventh switch are turned on, the first flying capacitor body and the second flying capacitor body simultaneously charge the output terminal capacitor.

7. The reconfigurable wide load range switched-capacitor DC-DC converter of claim 1, wherein: The first flying capacitor body and the second flying capacitor body are configured to: When the DC-DC converter is in a light load state, the first flying capacitor body and the second flying capacitor body both select a capacitor with a small capacitance value and a low frequency clock signal; When the DC-DC converter is in a heavy load state, the first flying capacitor body and the second flying capacitor body both select a capacitor with a large capacitance value and a high frequency clock signal.

8. The reconfigurable wide load range switched-capacitor DC-DC converter of claim 2, wherein: The tenth switch and the eleventh switch are multiplexing switches.

9. A control method applied in the reconfigurable wide load range switched-capacitor DC-DC converter of any one of claims 1-8, characterized in that, The method comprises: When the DC-DC converter is in a light load state, controlling the first flying capacitor body and the second flying capacitor body to both select a capacitor with a small capacitance value and a low frequency clock signal; and When the DC-DC converter is in a heavy load state, controlling the first flying capacitor body and the second flying capacitor body to both select a capacitor with a large capacitance value and a high frequency clock signal.

10. A reconfigurable wide load range switched capacitor DC-DC converter system, characterized by, The system comprises: The reconfigurable wide load range switched-capacitor DC-DC converter of any one of claims 1-8; a processing unit; and a non-transitory readable storage medium having instructions stored thereon that, when executed by the processing unit, cause the processing unit to perform the following steps: When the DC-DC converter is in a light load state, controlling the first flying capacitor body and the second flying capacitor body to both select a capacitor with a small capacitance value and a low frequency clock signal; and When the DC-DC converter is in a heavy load state, controlling the first flying capacitor body and the second flying capacitor body to both select a capacitor with a large capacitance value and a high frequency clock signal. When the DC-DC converter is in a heavy load state, the first flying capacitor main body and the second flying capacitor main body are controlled to select the capacitor with a large capacitance value and a high frequency clock signal.

Images