Non-isolation switch converter and control method thereof

Abstract

The invention discloses a non-isolation switch converter and a control method thereof. In response to a forward mode, a first voltage is received between the first voltage terminal and the first voltage return terminal, and a second voltage lower than the first voltage is provided between the second voltage terminal and the second voltage return terminal. In response to a reverse mode, a first voltage is provided between the first voltage terminal and the first voltage return terminal, and a second voltage is received between the second voltage terminal and the second voltage return terminal. The non-isolated switching converter includes a high-voltage side circuit and a low-voltage side circuit. The high-voltage side circuit comprises a first switching tube and a second switching tube which are coupled in series between the first end and the second end of the high-voltage side circuit, and the first end of the high-voltage side circuit is coupled to a first voltage terminal through a protection switching tube. The low voltage side circuit includes a third switching tube coupled between the second end of the high voltage side circuit and the second voltage return terminal. The non-isolation switch converter has the advantages of high efficiency, high power density and high reliability.

Description

Technical Field

[0001] This invention relates to an electronic circuit, and more specifically, to a non-isolated switch converter and its control method. Background Technology

[0002] A DC-DC switching converter converts a DC input voltage into a regulated DC output voltage. For example, a boost converter provides a DC output voltage higher than the input voltage, a buck converter provides a DC output voltage lower than the input voltage, a buck-boost converter can provide a DC output voltage higher or lower than the input voltage, and a regulated DC output voltage at the same level as the input voltage can also be provided.

[0003] Several circuit topologies exist for implementing the aforementioned DC-DC switching converters, including hard-switching bridge circuits, phase-shifted soft-switching bridge circuits, soft-switching bridge circuits with series resonant slots, and switched-capacitor converters. The problems with currently available DC-DC switching converters include low efficiency, low power density, and relatively high manufacturing costs. Summary of the Invention

[0004] Therefore, the purpose of this invention is to solve the above-mentioned technical problems of the prior art, and to propose a non-isolated switch converter and its control method.

[0005] According to an embodiment of the present invention, a non-isolated switching converter is provided, comprising: a first voltage terminal and a first voltage return terminal; a second voltage terminal and a second voltage return terminal, wherein the second voltage return terminal is coupled to the first voltage return terminal; a first protection switch coupled to the first voltage terminal; a high-voltage side circuit including a first terminal, a second terminal, and a first switch and a second switch connected in series between the first terminal and the second terminal of the high-voltage side circuit, wherein the first terminal of the high-voltage side circuit is coupled to the first voltage terminal through the first protection switch, and the first protection switch and the first switch form a back-to-back switch pair; and a low-voltage side circuit coupled to the second voltage terminal and the second voltage return terminal, wherein the low-voltage side circuit includes a third switch coupled between the second terminal and the second voltage return terminal of the high-voltage side circuit; wherein, in a forward mode, the non-isolated switching converter receives a first voltage between the first voltage terminal and the first voltage return terminal, and provides a second voltage lower than the first voltage between the second voltage terminal and the second voltage return terminal; and in a reverse mode, the non-isolated switching converter provides the first voltage between the first voltage terminal and the first voltage return terminal, and receives the second voltage between the second voltage terminal and the second voltage return terminal.

[0006] According to an embodiment of the present invention, a non-isolated switch converter is also provided, comprising: a first voltage terminal and a first voltage return terminal; a second voltage terminal and a second voltage return terminal, wherein the second voltage return terminal is coupled to the first voltage return terminal; a first protection switch coupled to the first voltage terminal; a second protection switch coupled to the first voltage terminal; a high-voltage side circuit including a first terminal, a second terminal, a third terminal, a fourth terminal, a first switch and a second switch connected in series between the first terminal and the second terminal of the high-voltage side circuit, and a third switch and a fourth switch connected in series between the third terminal and the fourth terminal of the high-voltage side circuit, wherein the first terminal of the high-voltage side circuit is coupled to the first voltage terminal through the first protection switch, and the third terminal of the high-voltage side circuit is coupled to the first voltage terminal through the second protection switch, wherein the first protection switch and the first switch form a back-to-back switch pair, and the second protection switch and the third switch form a back-to-back switch pair; a low-voltage side circuit, coupled to the first voltage terminal; and a second voltage return terminal and a third voltage return terminal. The low-voltage side circuit includes a fifth switch coupled between the second terminal of the high-voltage side circuit and the second voltage return terminal, and a sixth switch coupled between the fourth terminal of the high-voltage side circuit and the second voltage return terminal; and an energy storage circuit including a first terminal and a second terminal, wherein the first terminal of the energy storage circuit is coupled to a common terminal of the first and second switches, and the second terminal of the energy storage circuit is coupled to a common terminal of the third and fourth switches; wherein, in a forward mode, the non-isolated switching converter receives a first voltage between its first voltage terminal and the first voltage return terminal, and provides a second voltage lower than the first voltage between its second voltage terminal and the second voltage return terminal; and in a reverse mode, the non-isolated switching converter provides the first voltage between its first voltage terminal and the first voltage return terminal, and receives the second voltage between its second voltage terminal and the second voltage return terminal.

[0007] According to an embodiment of the present invention, a control method for a non-isolated switching converter is also provided, comprising: in response to a forward mode, the non-isolated switching converter receiving a first voltage between a first voltage terminal and a first voltage return terminal, and providing a second voltage lower than the first voltage between a second voltage terminal and a second voltage return terminal; in response to a reverse mode, the non-isolated switching converter providing the first voltage between the first voltage terminal and the first voltage return terminal, and receiving the second voltage between the second voltage terminal and the second voltage return terminal; and coupling a high-voltage side circuit to the first voltage terminal via a protection switch, wherein the high-voltage side circuit includes a first terminal and a second terminal. The circuit includes a first switch and a second switch connected in series between the first and second terminals of the high-voltage side circuit, with the protection switch and the first switch forming a back-to-back switch pair; the non-isolated switch converter is coupled to a second voltage terminal via a low-voltage side circuit, the low-voltage side circuit including a third switch coupled between the second terminal and the second voltage return terminal of the high-voltage side circuit; and a first drive signal for driving the protection switch is provided by a first driver, a second drive signal for driving the first switch is provided by a second driver, a third drive signal for driving the second switch is provided by a third driver, and a fourth drive signal for driving the third switch is provided by a fourth driver.

[0008] The non-isolated switch converter of this invention has high efficiency, high power density, and high reliability. Attached Figure Description

[0009] To better understand this invention, it will be described in detail with reference to the following figures:

[0010] Figure 1 This is a circuit diagram of a power supply system 100 according to an embodiment of the present invention;

[0011] Figure 2 This is a circuit diagram of a non-isolated switch converter 200 according to an embodiment of the present invention;

[0012] Figure 3 This is a circuit diagram of a non-isolated switch converter 300 according to an embodiment of the present invention;

[0013] Figure 4A This is a schematic diagram of a non-isolated switch converter 300 according to the present invention operating in a first switching mode;

[0014] Figure 4B This is a schematic diagram of a non-isolated switch converter 300 according to the present invention operating in a second switching mode;

[0015] Figure 5 This is a schematic diagram of a non-isolated switch converter 300 according to the present invention operating in a third switching mode;

[0016] Figure 6 This is a circuit diagram of a non-isolated switching converter 400 according to an embodiment of the present invention;

[0017] Figure 7 This is a circuit diagram of the charging circuit 246 according to an embodiment of the present invention;

[0018] Figure 8 This is a circuit diagram of a non-isolated switch converter 500 according to an embodiment of the present invention;

[0019] Figure 9 This is a circuit diagram of a non-isolated switching converter 600 according to an embodiment of the present invention;

[0020] Figure 10 This is a circuit diagram of a non-isolated switching converter 700 according to an embodiment of the present invention;

[0021] Figure 11 This is a circuit diagram of a non-isolated switch converter 700B according to an embodiment of the present invention;

[0022] Figure 12 This is a circuit diagram of a non-isolated switching converter 800 according to an embodiment of the present invention;

[0023] Figure 13 This is a circuit diagram of a non-isolated switching converter 900 according to an embodiment of the present invention;

[0024] Figure 14A This is a schematic diagram of a non-isolated switch converter 900 according to the present invention operating in a first switching mode;

[0025] Figure 14B This is a schematic diagram of a non-isolated switch converter 900 according to the present invention operating in a second switching mode;

[0026] Figure 15A This is a schematic diagram of a non-isolated switch converter 900 according to the present invention operating in a third switching mode;

[0027] Figure 15B This is a schematic diagram of a non-isolated switch converter 900 according to the present invention operating in a fourth switching mode;

[0028] Figure 16 This is a circuit diagram of a non-isolated switch converter 900A according to an embodiment of the present invention;

[0029] Figure 17 This is a circuit diagram of a non-isolated switch converter 1000 according to an embodiment of the present invention;

[0030] Figure 18This is a circuit diagram of a non-isolated switch converter 1100 according to an embodiment of the present invention;

[0031] Figure 19 This is a circuit diagram of the driver chip 111 according to an embodiment of the present invention;

[0032] Figure 20 According to the embodiments of the present invention Figure 18 Waveform diagram 230 of the non-isolated switch converter 1100 shown;

[0033] Figure 21 This is a circuit diagram of a non-isolated switch converter 1200 according to an embodiment of the present invention;

[0034] Figure 22 This is a circuit diagram of the driver chip 81 according to an embodiment of the present invention;

[0035] Figure 23 This is a flowchart of a control method 26 for a non-isolated switching converter according to an embodiment of the present invention.

[0036] In the accompanying drawings, the same or corresponding reference numerals are used to denote the same or corresponding elements. Detailed Implementation

[0037] Specific embodiments of the present invention will now be described in detail. It should be noted that the embodiments described herein are for illustrative purposes only and are not intended to limit the invention. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other instances, well-known circuits, materials, or methods have not been specifically described to avoid obscuring the invention.

[0038] Throughout this specification, references to “an embodiment,” “an example,” or “an example” mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases “in an embodiment,” “in an embodiment,” “an example,” or “an example” appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the accompanying drawings provided herein are for illustrative purposes and are not necessarily drawn to scale. It should be understood that when an element is referred to as “coupled to” or “connected to” another element, it can be directly coupled to or coupled to the other element, or there may be intermediate elements. Conversely, when an element is referred to as “directly coupled to” or “directly connected to” another element, there are no intermediate elements. The same reference numerals indicate the same elements. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0039] Figure 1 This is a circuit diagram of a power supply system 100 according to an embodiment of the present invention. The power supply system 100 includes a three-level power supply. For example... Figure 1 As shown, the AC-to-DC converter 10 provides the first-stage power supply, the non-isolated switch converter 20 provides the second-stage power supply, and the voltage regulator 14 and point-of-load converters 15-16 provide the third-stage power supply, offering different supply voltages to multiple loads. For example, the voltage regulator 14 provides the processor load with supply voltage VO1, and the point-of-load converters 15-16 provide supply voltages VO2-VO3 to multiple point-of-load loads respectively. Those skilled in the art will understand that the circuit structure of the third-stage power supply is not limited to... Figure 1The illustrated embodiments may include, for example, different numbers of voltage regulators or point-of-load converters, or other types of converters. In one embodiment, AC-to-DC converter 10 receives an AC input voltage VAC and converts it to a DC voltage VH. The AC input voltage VAC may be, for example, AC mains power. Non-isolated switching converter 20 receives the DC voltage VH and converts it to a DC voltage VL to supply power to the next stage, wherein the DC voltage VL is lower than the DC voltage VH. The DC voltage VH may be, for example, equal to 48V, and the DC voltage VL may be, for example, equal to 5V. In one embodiment, non-isolated switching converter 20 may operate in a positive mode, i.e., receiving the DC voltage VH between voltage terminal 101 and voltage return terminal 102, and supplying the DC voltage VL between voltage terminal 103 and voltage return terminal 104. In one embodiment, voltage return terminal 104 and voltage return terminal 102 are both coupled to reference ground GND. In one embodiment, the non-isolated switch converter 20 can also operate in reverse mode, i.e., receiving a DC voltage VL between voltage terminal 103 and voltage return terminal 104, and providing a DC voltage VH between voltage terminal 101 and voltage return terminal 102.

[0040] exist Figure 1 In the illustrated embodiment, the non-isolated switching converter 20 further includes a protection switch 11 coupled to voltage terminal 101, a high-voltage side circuit 12, and a low-voltage side circuit 13. The protection switch 11 prevents current from flowing from voltage terminal 103 into voltage terminal 101, thereby preventing damage to the non-isolated switching converter 20 due to the failure of its internal protection function in the event of a short circuit at voltage terminal 101. The high-voltage side circuit 12 includes a first terminal 121, a second terminal 122, and at least two switches, such as switches 123 and 124, connected in series between the first terminal 121 and the second terminal 122. In another embodiment, the high-voltage side circuit 12 may also include multiple switches connected in series between the first terminal 121 and the second terminal 122, and is not limited to this embodiment. Figure 1 The two switching transistors are shown. The first terminal 121 of the high-voltage side circuit 12 is coupled to the voltage terminal 101 via a protection switching transistor 11. The low-voltage side circuit 13 is coupled to the voltage terminal 103 and the voltage return terminal 104. The low-voltage side circuit 13 includes at least one switching transistor 131 coupled between the second terminal 122 of the high-voltage side circuit 12 and the voltage return terminal 104. In another embodiment, multiple switching transistors may also be included between the second terminal 122 of the high-voltage side circuit 12 and the voltage return terminal 104. In one embodiment, the switching transistor 131 may be directly coupled to the second terminal 122 of the high-voltage side circuit 12, or it may be coupled to the second terminal 122 of the high-voltage side circuit 12 via other components. Figure 1The non-isolated switching converter 20 shown serves as an intermediate-stage voltage conversion circuit, enabling the power supply system to achieve higher conversion efficiency and power density. It can also be flexibly applied in situations where reverse power supply from voltage terminal 103 to voltage terminal 101 is required, exhibiting high reliability.

[0041] Figure 2 This is a circuit diagram of a non-isolated switching converter 200 according to an embodiment of the present invention. Figure 2 In the illustrated embodiment, the non-isolated switchgear 200 includes a protection switch Q5, a high-voltage side circuit 22, and a low-voltage side circuit 23. When the non-isolated switchgear 200 operates in forward mode, voltage terminal 101 receives voltage VH, and voltage terminal 103 provides a voltage VL lower than VH. Current can flow from voltage terminal 101 to voltage terminal 103, as shown by dashed line 201. When the non-isolated switchgear 200 operates in reverse mode, voltage terminal 101 provides voltage VH, and voltage terminal 103 receives voltage VL. Current can flow from voltage terminal 103 to voltage terminal 101, as shown by solid line 202. In one embodiment, capacitor Cin is coupled between voltage terminal 101 and voltage return terminal 102 to stabilize voltage VH, and capacitor Co is coupled between voltage terminal 103 and voltage return terminal 104 to stabilize voltage VL.

[0042] exist Figure 2 In the illustrated embodiment, the high-voltage side circuit 22 includes a first terminal 221, a second terminal 222, and switching transistors Q1 to Q2 connected in series between the first terminal 221 and the second terminal 222 of the high-voltage side circuit 22. The first terminal 221 of the high-voltage side circuit 22 is coupled to the voltage terminal 101 through a protection switching transistor Q5. Those skilled in the art will understand that the switching transistors Q1 to Q2 and the protection switching transistor Q5 may include, for example, controllable switching devices such as metal-oxide-semiconductor field-effect transistors (MOSFETs), crystal field-effect transistors (JFETs), bipolar junction transistors (BJTs), superjunction transistors (SJTs), and insulated-gate bipolar transistors (IGBTs). In one embodiment, the protection switching transistor Q5 and the switching transistor Q1 form a back-to-back switching pair, such that the drain terminal of the protection switching transistor Q5 and the drain terminal of the switching transistor Q1 are coupled together, so that the cathode terminal of the parasitic diode of the protection switching transistor Q5 and the cathode terminal of the parasitic diode of the switching transistor Q1 are opposite each other.

[0043] In one embodiment, the source terminal of the protection switch Q5 is coupled to voltage terminal 101, and the drain terminal of the protection switch Q5 is coupled to the drain terminal of the switch Q1. The source terminal of the switch Q1 is coupled to the drain terminal of the switch Q2, forming a common terminal 223 for the switches Q1 and Q2. The source terminal of the switch Q2 serves as the second terminal 222 of the high-voltage side circuit 22 and is coupled to the low-voltage side circuit 23. In one embodiment, the high-voltage side circuit 22 further includes an energy storage circuit 224, one end of which is coupled to the common terminal 223 of the switches Q1 and Q2, and the other end of which is coupled to reference ground GND and / or to the low-voltage side circuit 23 (e.g., ...). Figure 2 (As shown by dashed line 225). In another embodiment, the other end of the energy storage circuit 224 may also be coupled to the voltage terminal 101 via other components or devices. The energy storage circuit 224 may include, for example, a capacitor, or a resonant tank consisting of an inductor and a capacitor. In another embodiment, the high-voltage side circuit 22 may include multiple energy storage circuits.

[0044] The low-voltage side circuit 23 is coupled to voltage terminal 103 and voltage return terminal 104, and provides or receives voltage VL between voltage terminal 103 and voltage return terminal 104. In one embodiment, when the non-isolated switch converter 200 operates in forward mode, the low-voltage side circuit 23 operates as a rectifier circuit, such as a half-wave rectifier circuit, a full-wave rectifier circuit with a center tap, or a bridge rectifier circuit. Figure 2 In the illustrated embodiment, the low-voltage side circuit 23 includes a magnetic element 233, a switching transistor S1, and a switching transistor S2. The magnetic element 233 can be, for example, a magnetic element composed of windings and a magnetic core, including a transformer, an inductor, etc., or it can be a capacitor. Those skilled in the art will understand that the specific circuit structure of the low-voltage side circuit 23 is not limited to... Figure 2 The embodiment shown. The switching transistors S1 to S2 in the low-voltage side circuit 23 can also be directly coupled to the high-voltage side circuit 22 without passing through the magnetic element 233. In one embodiment, the low-voltage side circuit 23 may, for example, not include the magnetic element 233.

[0045] In one embodiment, switch S1 is coupled between magnetic element 233 and voltage return terminal 104, and switch S2 is coupled between magnetic element 233 and voltage return terminal 104. In one embodiment, switch S1 can be coupled to the second terminal 222 of high-voltage side circuit 22 via magnetic element 233, or it can be directly coupled to the second terminal 222 of high-voltage side circuit 22. Figure 2In the illustrated embodiment, the switching transistors S1 to S2 are controllable switching devices with control terminals, such as metal-oxide-semiconductor field-effect transistors (MOSFETs), crystal field-effect transistors (JFETs), bipolar junction transistors (BJTs), superjunction transistors (SJTs), insulated gate bipolar transistors (IGBTs), etc.

[0046] In one embodiment, the non-isolated switching converter 200 further includes a drive circuit 24 that provides drive signals to the switching transistors in the non-isolated switching converter 200. For example, it provides a drive signal Vg1 to the gate terminal of switching transistor Q1 to drive switching transistor Q1, a drive signal Vg2 to the gate terminal of switching transistor Q2 to drive switching transistor Q2, a drive signal Vg5 to the gate terminal of protection switching transistor Q5 to drive protection switching transistor Q5, a drive signal Vgs1 to the gate terminal of switching transistor S1 to drive switching transistor S1, and a drive signal Vgs2 to the gate terminal of switching transistor S2 to drive switching transistor S2. In one embodiment, the drive circuit 24 includes a positive power supply terminal coupled to the supply voltage Vdrv and a negative power supply terminal coupled to the reference ground GND.

[0047] Figure 3 This is a circuit diagram of a non-isolated switching converter 300 according to an embodiment of the present invention. The non-isolated switching converter 300 includes a protection switch Q5, a high-voltage side circuit composed of switches Q1, Q2, and an energy storage circuit 224, a low-voltage side circuit composed of switches S1, S2, and a magnetic element 233, and a drive circuit 34. Figure 3 In the illustrated embodiment, the energy storage circuit 224 includes a resonant slot composed of a resonant inductor Lr, the magnetizing inductance Lm of the primary winding W1 of the transformer, and a resonant capacitor Cr. The resonant inductor Lr can, for example, be formed by the leakage inductance of the primary winding W1 of the transformer. Those skilled in the art will understand that the specific circuit structure of the energy storage circuit 224 is not limited to... Figure 3 In the illustrated embodiment, the energy storage circuit 224 may also include other forms of resonant tanks, such as a resonant tank composed of a resonant inductor and a resonant capacitor, a resonant tank composed of a resonant inductor and two resonant capacitors, or a resonant tank composed of multiple resonant inductors and multiple resonant capacitors, etc. Figure 3 In the illustrated embodiment, one end of the energy storage circuit 224 is coupled to the common terminal of switching transistors Q1 and Q2, and the other end of the energy storage circuit 224 is coupled to reference ground GND. The magnetic element 233 includes, for example, the secondary winding W2 of a transformer. Figure 3 In the embodiment shown, one end of the secondary winding W2 is coupled to the common terminal of the switching transistors S1 and Q2, the other end of the secondary winding W2 is coupled to the switching transistor S2 and the reference ground GND, and the center tap of the secondary winding W2 is coupled to the voltage terminal 103 to provide or receive voltage VL.

[0048] In one embodiment, the drive circuit 34 includes a positive power supply terminal coupled to the supply voltage Vdrv and a negative power supply terminal coupled to the reference ground GND. Figure 3 In the illustrated embodiment, the drive circuit 34 includes a driver 241 that provides a drive signal Vg5 to the protection switch Q5, and a driver 242 that provides a drive signal Vg1 to the switch Q1. Driver 241 is coupled to both ends of the bootstrap capacitor Cb1, and the voltage Vd1 across the bootstrap capacitor Cb1 powers driver 241. In one embodiment, one end of the bootstrap capacitor Cb1 is coupled to voltage terminal 101, i.e., the source terminal of the switch Q5, and the other end of the bootstrap capacitor Cb1 is coupled to a charging circuit that charges the bootstrap capacitor Cb1, such as, but not limited to, a charging circuit for charging the bootstrap capacitor Cb1. Figure 3 The charging switch Db1 and bootstrap capacitor Cb2 are shown. In another embodiment, the charging circuit for bootstrap capacitor Cb1 may also include a charge pump circuit, for example. Driver 242 is coupled to both ends of bootstrap capacitor Cb2, and the voltage Vd2 across bootstrap capacitor Cb2 supplies power to driver 242. In one embodiment, one end of bootstrap capacitor Cb2 is coupled to the common terminal 223 of switches Q1 and Q2, and the other end of bootstrap capacitor Cb2 is coupled to bootstrap capacitor Cb1 through charging switch Db1. When protection switches Q5 and Q1 are turned on, bootstrap capacitor Cb2 charges bootstrap capacitor Cb1 through charging switch Db1. When the voltage across bootstrap capacitor Cb1 is insufficient to drive protection switch Q5 to turn on, the current charging bootstrap capacitor Cb1 flows through the parasitic diode of protection switch Q5 and switch Q1. The other end of bootstrap capacitor Cb2 is also coupled to a charging circuit for charging bootstrap capacitor Cb2, for example, including but not limited to... Figure 3 The charging switch Q2 and bootstrap capacitor Cb3 are shown. When switch Q2 is turned on, bootstrap capacitor Cb3 charges bootstrap capacitor Cb2 through charging switch Q2. In another embodiment, the charging circuit for bootstrap capacitor Cb2 may also include a charge pump circuit, for example. In one embodiment, driver 241 and driver 242 receive control signal PWMP1 and provide drive signals Vg5 and Vg1 respectively according to control signal PWMP1, so that protection switch Q5 and switch Q1 are synchronously turned on and off under the control of control signal PWMP1. Those skilled in the art will understand that there may be a delay between the synchronous turn-on and turn-off of protection switch Q5 and switch Q1.

[0049] exist Figure 3In the illustrated embodiment, the driving circuit 34 further includes a driver 243 that provides a driving signal Vg2 to the switch Q2 and a driver 244 that provides a driving signal Vgs1 to the switch S1. The driver 243 is coupled to both ends of the bootstrap capacitor Cb3, and the voltage Vd3 across the bootstrap capacitor Cb3 powers the driver 243. In one embodiment, one end of the bootstrap capacitor Cb3 is coupled to the source terminal of the switch Q2, and the other end of the bootstrap capacitor Cb3 is coupled to a charging circuit that charges the bootstrap capacitor Cb3, such as, but not limited to, a charging circuit for charging the bootstrap capacitor Cb3. Figure 3 The charging switch Db3 and the supply voltage Vdrv are shown. In... Figure 3 In the illustrated embodiment, the other end of the bootstrap capacitor Cb3 is simultaneously coupled to the bootstrap capacitor Cb3 via the charging switch Db2. When the switch S1 is turned on, the supply voltage Vdrv charges the bootstrap capacitor Cb3 through the charging switch Db3. In another embodiment, the charging circuit of the bootstrap capacitor Cb3 may, for example, include a charge pump circuit. In one embodiment, the driver 243 receives the control signal PWMP2 and provides a drive signal Vg2 according to the control signal PWMP2, causing the switch Q2 to turn on and off under the control of the control signal PWMP2. In one embodiment, the control signals PWMP1 and PWMP2 are, for example, complementary in phase to control the complementary conduction of switches Q2 and Q1. Those skilled in the art will understand that a dead time may exist between the drive signals Vg2 and Vg1 to prevent switches Q2 and Q1 from turning on simultaneously. The driver 244 receives the supply voltage Vdrv as its drive power supply. In one embodiment, capacitor Cdr is coupled between the supply voltage Vdrv and the reference ground GND, and its two ends are coupled to driver 244 to provide a stable power supply. In one embodiment, driver 244 receives control signal PWMS1 and provides drive signal Vgs1 according to control signal PWMS1 to drive switch S1 to turn on and off. In one embodiment, control signal PWMS1 and control signal PWMP2 are, for example, complementary in phase to control switch S1 and switch Q1 to conduct complementaryly. Those skilled in the art will understand that a dead time may exist between drive signal Vgs1 and drive signal Vg1 to prevent switch S1 and switch Q1 from conducting simultaneously. Figure 3In the illustrated embodiment, the driving circuit 34 further includes a driver 245 that provides a driving signal Vgs2 to the switch S2. The driver 245 receives a supply voltage Vdrv as its driving power supply. In one embodiment, the driver 245 receives a control signal PWMS2 and provides the driving signal Vgs2 according to the control signal PWMS2 to drive the switch S2 to turn on and off. In one embodiment, the control signals PWMS1 and PWMS2 are, for example, complementary in phase to control the complementary conduction of the switches S2 and S1. Those skilled in the art will understand that a dead time may exist between the driving signals Vgs1 and Vgs2 to prevent the switches S1 and S2 from turning on simultaneously. The charging switches Db1 to Db3 may include, for example, diodes and controllable switches (such as MOSFETs, JFETs, BJTs, SJTs, IGBTs, etc.). In one embodiment, the driving circuit 34 may be integrated on one or more driving chips.

[0050] The driving circuit 34 of the non-isolated switching converter provided in this embodiment of the invention charges the bootstrap capacitor Cb1 through the bootstrap capacitor Cb2 when the switching transistor Q1 is turned on, providing the power required to drive the protection switching transistor Q5 in a simple way, thereby ensuring the stability and reliable operation of the system. In particular, when the voltage across the bootstrap capacitor Cb1 is insufficient to drive the protection switching transistor Q5, the bootstrap capacitor Cb2 can charge the bootstrap capacitor Cb1 through the parasitic diode of the protection switching transistor Q5, the switching transistor Q1, and the charging switching transistor Db1.

[0051] Figure 4A This is a schematic diagram of a non-isolated switch converter 300 according to the present invention operating in a first switching mode. Figure 4A In the illustrated embodiment, in the first switching mode, switches Q1 and S1 are turned on, while switches Q2 and S2 are turned off. Since switch S1 is on, the supply voltage Vdrv charges the bootstrap capacitor Cb3 through the charging switch Db3, increasing the voltage across Cb3. Current then flows back to reference ground GND and capacitor Cdr through switch S1. The current loop for charging the bootstrap capacitor Cb3 is as follows... Figure 4A The dashed line with an arrowhead is shown in the image. Figure 4A In the illustrated embodiment, when the voltage across the bootstrap capacitor Cb1 is insufficient to power the driver 241 and provide the drive signal Vg5, the protection switch Q5 remains off. Before the protection switch Q5 is turned on, the bootstrap capacitor Cb2 is charged by the charging switch Db1 when the switch Q1 is on, causing the voltage across Cb1 to rise. The charging current for Cb1 flows back to the bootstrap capacitor Cb2 through the parasitic diode of the protection switch Q5 and the switch Q1. The current loop for charging the bootstrap capacitor Cb1 is as follows: Figure 4A The solid line with arrows is shown in the figure. In one embodiment, the non-isolated switching converter 300 enters the second switching mode until the voltage across the bootstrap capacitor Cb1 is sufficient to drive the protection switch Q5 to turn on.

[0052] Figure 4B This is a schematic diagram of a non-isolated switch converter 300 according to the present invention operating in a second switching mode. Figure 4B In the illustrated embodiment, in the second switching mode, protection switch Q5, switch Q1, and switch S1 are turned on, while switch Q2 and switch S2 are turned off. Since switch Q1 and protection switch Q5 are on, bootstrap capacitor Cb2 is charged through charging switch Db1, increasing the voltage across bootstrap capacitor Cb1. Current then flows back to bootstrap capacitor Cb2 through protection switch Q5 and switch Q1. The current loop for charging bootstrap capacitor Cb1 is as follows... Figure 4A The solid line with an arrowhead is shown in the image.

[0053] Figure 5 This is a schematic diagram of a non-isolated switch converter 300 according to the present invention operating in a third switching mode. Figure 5 In the illustrated embodiment, in the third switching mode, protection switches Q5, Q1, and S1 are turned off, while switches Q2 and S2 are turned on. Because switch Q2 is on, bootstrap capacitor Cb3 is charged through charging switch Db2, increasing the voltage across bootstrap capacitor Cb2. Current then flows back to bootstrap capacitor Cb3 through switch Q2. The current loop for charging bootstrap capacitor Cb2 is as follows: Figure 5 The solid line with an arrowhead is shown in the image.

[0054] Figure 6 This is a circuit diagram of a non-isolated switching converter 400 according to an embodiment of the present invention. The non-isolated switching converter 400 includes a protection switch Q5, a high-voltage side circuit composed of switches Q1, Q2, and an energy storage circuit 224, a low-voltage side circuit composed of switches S1, S2, and a magnetic element 233, and a drive circuit 44. Figure 6 In the illustrated embodiment, the drive circuit 44 includes a charging circuit 246 for charging the bootstrap capacitors Cb1 and Cb2. Figure 6As shown, charging circuit 246 is coupled to both ends of capacitor Cdr1 to receive supply voltage Vdrv. Charging circuit 246 provides supply voltage Vd1 across bootstrap capacitor Cb1 and supply voltage Vd2 across bootstrap capacitor Cb2. In one embodiment, supply voltage Vdrv charges bootstrap capacitor Cb2 through charging circuit 246. In one embodiment, charging circuit 246 includes charging switch Sc coupled between bootstrap capacitors Cb1 and Cb2. When protection switch Q5 and switch Q1 are turned on, charging switch Sc is turned on, and bootstrap capacitor Cb2 charges bootstrap capacitor Cb1 through charging switch Sc. In one embodiment, drive circuit 44 can be integrated on one or more drive chips.

[0055] Figure 7 This is a circuit diagram of a charging circuit 246 according to an embodiment of the present invention. Those skilled in the art will understand that the specific structure of the charging circuit 246 is not limited to... Figure 7 The specific embodiment is shown. In Figure 7 In the illustrated embodiment, the charging circuit 246 includes a charge pump circuit 70 composed of switches 72-75 and an oscillator 71, a charging switch Sc, and a flying capacitor Cpn. One end of switch 72 is coupled to the supply voltage Vdrv, and the other end of switch 72 is coupled to one end of switch 73. The other end of switch 73 is coupled to one end of bootstrap capacitor Cb2 and the charging switch Sc. One end of switch 74 is coupled to reference ground GND, and the other end of switch 74 is coupled to one end of switch 75. The other end of switch 75 is coupled to the other end of bootstrap capacitor Cb2. The common terminal of switches 72 and 73 is coupled to the charge pump pin CP, and the common terminal of switches 74 and 75 is coupled to the charge pump pin CN. Switches 72-75 may include, for example, MOSFETs, JFETs, BJTs, SJTs, IGBTs, etc.

[0056] In one embodiment, oscillator 71 controls switches 72 and 74 to conduct at a certain frequency to charge the flying capacitor Cpn. For example, the supply voltage Vdrv charges the flying capacitor Cpn through switches 72 and 74. When switches 72 and 74 are off, oscillator 71 controls switches 73 and 75 to conduct at a certain frequency to charge the bootstrap capacitor Cb2. For example, the flying capacitor Cpn charges the bootstrap capacitor Cb2 through switches 73 and 75. In one embodiment, when protection switches Q5 and Q1 are on, charging switch Sc is controlled to conduct, and bootstrap capacitor Cb2 is charged through protection switches Q5, Q1, and charging switch Sc.

[0057] Figure 8This is a circuit diagram of a non-isolated switching converter 500 according to an embodiment of the present invention. Figure 8 In the illustrated embodiment, the non-isolated switchgear 500 includes a protection switch Q5, a high-voltage side circuit 51 composed of switches Q1-Q2 and an energy storage circuit Cr0, a low-voltage side circuit 52 composed of switches S3-S6 and an energy storage circuit Cd, and a drive circuit 53. Figure 8 In the illustrated embodiment, the energy storage circuits Cr0 and Cd include, for example, capacitors. When the non-isolated switching converter 500 operates in forward mode, voltage terminal 101 receives voltage VH, and voltage terminal 103 provides a voltage VL lower than VH; current can flow from voltage terminal 101 to voltage terminal 103. When the non-isolated switching converter 500 operates in reverse mode, voltage terminal 101 provides voltage VH, and voltage terminal 103 receives voltage VL; current can flow from voltage terminal 103 to voltage terminal 101.

[0058] The drive circuit 53 provides drive signals to the switching transistors of the non-isolated switching converter 500. For example, it provides drive signal Vg1 to the gate terminal of switching transistor Q1 to drive switching transistor Q1, drive signal Vg2 to the gate terminal of switching transistor Q2 to drive switching transistor Q2, drive signal Vg5 to the gate terminal of protection switching transistor Q5 to drive protection switching transistor Q5, drive signal Vgs3 to the gate terminal of switching transistor S3 to drive switching transistor S3, drive signal Vgs4 to the gate terminal of switching transistor S4 to drive switching transistor S4, drive signal Vgs5 to the gate terminal of switching transistor S5 to drive switching transistor S5, and drive signal Vgs6 to the gate terminal of switching transistor S6 to drive switching transistor S6. In one embodiment, the drive circuit 53 includes a positive power supply terminal coupled to the supply voltage Vdrv and a negative power supply terminal coupled to the reference ground GND. The specific structure of the drive circuit 53 is similar to that of the drive circuit 34 or the drive circuit 44, and will not be described in detail here for the sake of simplicity.

[0059] Figure 9 This is a circuit diagram of a non-isolated switching converter 600 according to an embodiment of the present invention. Figure 9 In the illustrated embodiment, the non-isolated switchgear 500 includes a protection switch Q5, a high-voltage side circuit 61 composed of switches Q1 to Q4 and an energy storage circuit 611, a low-voltage side circuit 62 composed of switches S3 to S6, and a drive circuit 63. Figure 9In the illustrated embodiment, the energy storage circuit 611 includes, for example, a resonant tank composed of capacitor Cr2 and inductor Lr0, a resonant tank composed of capacitor Cr3 and inductor Lr3, and capacitor Cd2. When the non-isolated switching converter 600 operates in forward mode, voltage terminal 101 receives voltage VH, and voltage terminal 103 provides a voltage VL lower than VH; current can flow from voltage terminal 101 to voltage terminal 103. When the non-isolated switching converter 600 operates in reverse mode, voltage terminal 101 provides voltage VH, and voltage terminal 103 receives voltage VL; current can flow from voltage terminal 103 to voltage terminal 101.

[0060] The drive circuit 63 provides drive signals to the switching transistors of the non-isolated switching converter 600. For example, it provides drive signal Vg1 to the gate terminal of switching transistor Q1 to drive switching transistor Q1, drive signal Vg2 to the gate terminal of switching transistor Q2 to drive switching transistor Q2, drive signal Vg3 to the gate terminal of switching transistor Q3 to drive switching transistor Q3, drive signal Vg4 to the gate terminal of switching transistor Q4 to drive switching transistor Q4, drive signal Vg5 to the gate terminal of protection switching transistor Q5 to drive protection switching transistor Q5, drive signal Vgs3 to the gate terminal of switching transistor S3 to drive switching transistor S3, drive signal Vgs4 to the gate terminal of switching transistor S4 to drive switching transistor S4, drive signal Vgs5 to the gate terminal of switching transistor S5 to drive switching transistor S5, and drive signal Vgs6 to the gate terminal of switching transistor S6 to drive switching transistor S6. In one embodiment, the drive circuit 63 includes a positive power supply terminal coupled to the supply voltage Vdrv and a negative power supply terminal coupled to the reference ground GND. The specific structure of the drive circuit 63 is similar to that of the drive circuit 34 or the drive circuit 44, and will not be described in detail here for the sake of simplicity.

[0061] Figure 10 This is a circuit diagram of a non-isolated switching converter 700 according to an embodiment of the present invention. Figure 10In the illustrated embodiment, the disconnector switch 700 includes a voltage terminal 101, a voltage return terminal 102, a voltage terminal 103, a voltage return terminal 104, a protection switch 11, a protection switch 91, a high-voltage side circuit 92, and a low-voltage side circuit 93. Protection switches 11 and 91 prevent excessive current Irev flowing into the voltage terminal 101 of the non-disconnector switch 700, thereby preventing damage to the non-disconnector switch 700 due to a short circuit in the voltage terminal 101 during reverse mode. When the non-disconnector switch 700 operates in forward mode, voltage terminal 101 receives voltage VH, and voltage terminal 103 provides a voltage VL lower than VH; current can flow from voltage terminal 101 to voltage terminal 103. When the non-disconnector switch 700 operates in reverse mode, voltage terminal 101 provides voltage VH, and voltage terminal 103 receives voltage VL; current can flow from voltage terminal 103 to voltage terminal 101.

[0062] The high-voltage side circuit 92 includes a first terminal 121, a second terminal 122, a third terminal 125, a fourth terminal 126, at least two switching transistors 123-124 connected in series between the first terminal 121 and the second terminal 122, and at least two switching transistors 127-128 connected in series between the third terminal 125 and the fourth terminal 126. The first terminal 121 of the high-voltage side circuit 92 is coupled to the voltage terminal 101 through a protection switching transistor 11, and the third terminal 125 of the high-voltage side circuit 92 is coupled to the voltage terminal 101 through a protection switching transistor 91. In another embodiment, the high-voltage side circuit 92 may also include multiple switching transistors connected in series between the first terminal 121 and the second terminal 122, and is not limited to this type of circuit. Figure 10 The two switching transistors are shown. In another embodiment, the high-voltage side circuit 92 may also include multiple switching transistors connected in series between the third terminal 125 and the fourth terminal 126, and is not limited to... Figure 10 The two switching transistors are shown.

[0063] The low-voltage side circuit 93 is coupled to voltage terminal 103 and voltage return terminal 104. The low-voltage side circuit 93 includes at least one switch 131 coupled between the second terminal 122 of the high-voltage side circuit 92 and voltage return terminal 104, and at least one switch 132 coupled between the fourth terminal 126 of the high-voltage side circuit 92 and voltage return terminal 104. In another embodiment, multiple switches may also be included between the second terminal 122 of the high-voltage side circuit 92 and voltage return terminal 104, and multiple switches may also be included between the fourth terminal 126 of the high-voltage side circuit 92 and voltage return terminal 104, without limitation. Figure 10The embodiment shown. In one embodiment, the switching transistor 131 can be directly coupled to the second terminal 122 of the high-voltage side circuit 92, or it can be coupled to the second terminal 122 of the high-voltage side circuit 92 through other components. The switching transistor 132 can be directly coupled to the fourth terminal 126 of the high-voltage side circuit 92, or it can be coupled to the fourth terminal 126 of the high-voltage side circuit 92 through other components.

[0064] Figure 11 This is a circuit diagram of a non-isolated switching converter 700B according to an embodiment of the present invention. Figure 12 Unlike the non-isolated switch converter 700 shown, in Figure 11 In the embodiment shown, the first terminal 121 and the third terminal 125 of the high-voltage side circuit 92 are coupled to the voltage terminal 101 through the protection switch 11.

[0065] Figure 12 This is a circuit diagram of a non-isolated switching converter 800 according to an embodiment of the present invention. The non-isolated switching converter 800 includes a voltage terminal 101, a voltage return terminal 102, a voltage terminal 103, a voltage return terminal 104, a protection switch Q5, a protection switch Q6, a high-voltage side circuit 62, and a low-voltage side circuit 63. When the non-isolated switching converter 800 operates in forward mode, the voltage terminal 101 is used to receive voltage VH, and the voltage terminal 103 is used to provide a voltage VL lower than voltage VH. Current can flow from the voltage terminal 101 to the voltage terminal 103, for example, sequentially through protection switch Q5, switch Q1, and switch Q4 to the voltage terminal 103, and sequentially through protection switch Q6, switch Q3, and switch Q2 to the voltage terminal 103. When the non-isolated switching converter 800 operates in reverse mode, voltage terminal 101 provides voltage VH, and voltage terminal 103 receives voltage VL. Current can flow from voltage terminal 103 to voltage terminal 101, for example, sequentially through switching transistors Q2, Q3, and protection switching transistor Q6, and sequentially through switching transistors Q4, Q1, and protection switching transistor Q5. Protection switching transistor Q5 is coupled between voltage terminal 101 and switching transistor Q1, and protection switching transistor Q6 is coupled between voltage terminal 101 and switching transistor Q3. This prevents current from flowing from voltage terminal 103 into voltage terminal 101, thus preventing damage to the non-isolated switching converter 800 due to the failure of its internal protection function in the event of a short circuit at voltage terminal 101. In another embodiment, switching transistor Q3 can also be coupled to voltage terminal 101 via switching transistor Q5, eliminating the need for protection switching transistor Q6.

[0066] The first terminal 621 of the high-voltage side circuit 62 is coupled to the voltage terminal 101 via a protection switch Q5; the second terminal 622 of the high-voltage side circuit 62 is coupled to the low-voltage side circuit 63; the third terminal 625 of the high-voltage side circuit 62 is coupled to the voltage terminal 101 via a protection switch Q6; and the fourth terminal 626 of the high-voltage side circuit 62 is coupled to the low-voltage side circuit 63. The high-voltage side circuit 62 includes at least two switches Q1-Q2 connected in series between its first terminal 621 and second terminal 622, at least two switches Q3-Q4 connected in series between its third terminal 625 and fourth terminal 626, and an energy storage circuit 624. In one embodiment, the source terminal of the protection switch Q6 is coupled to the voltage terminal 101, and the drain terminal of the protection switch Q6 is coupled to the drain terminal of the switch Q3. The source terminal of the switch Q3 is coupled to the drain terminal of the switch Q4, forming a common terminal 627 for the switches Q3 and Q4. The source terminal of the switching transistor Q4 is coupled to the low-voltage side circuit 63 as the fourth terminal 626 of the high-voltage side circuit 62. Figure 12 In the illustrated embodiment, one end of the energy storage circuit 624 is coupled to the common terminal 223 of switching transistors Q1 and Q2, and the other end of the energy storage circuit 624 is coupled to the common terminal 627 of switching transistors Q3 and Q4. In one embodiment, the energy storage circuit 624 may also be coupled to the second terminal 622 and / or the fourth terminal 626 of the high-voltage side circuit 62, respectively. Figure 2 Similar to the low-voltage side circuit 23 shown, the low-voltage side circuit 63 includes a magnetic element 633, a switching transistor S1, and a switching transistor S2. In one embodiment, the low-voltage side circuit 63 can be coupled to the second terminal 622 and the fourth terminal 626 of the high-voltage side circuit 62, for example, through the magnetic element 633. In another embodiment, the switching transistors S1 and S2 in the low-voltage side circuit 63 can also be directly coupled to the high-voltage side circuit 62, for example, switching transistor S1 is coupled to the second terminal 622 of the high-voltage side circuit 62, and switching transistor S2 is coupled to the fourth terminal 626 of the high-voltage side circuit 62.

[0067] In one embodiment, protection switch Q6 and switch Q3 form a back-to-back switching pair, such as by coupling the drain terminals of protection switch Q6 and switch Q3 together, so that the cathode terminals of the parasitic diodes of protection switch Q6 and switch Q3 are opposite to each other. Those skilled in the art will understand that switches Q3-Q4 and protection switch Q6 may include, for example, controllable switching devices such as metal-oxide-semiconductor field-effect transistors (MOSFETs), crystal field-effect transistors (JFETs), bipolar junction transistors (BJTs), superjunction transistors (SJTs), and insulated-gate bipolar transistors (IGBTs).

[0068] The non-isolated switching converter 800 further includes a drive circuit 64. The drive circuit 64 is coupled between the supply voltage Vdrv and the reference ground GND, and provides drive signals Vg1 to Vg6, Vgs1, and Vgs2 to drive the switching devices in the non-isolated switching converter 800, respectively.

[0069] Figure 13 This is a circuit diagram of a non-isolated switch converter 900 according to an embodiment of the present invention. The non-isolated switch converter 900 includes a high-voltage side circuit composed of protection switch Q5, protection switch Q6, switches Q1 to Q4 and energy storage circuit 624, a low-voltage side circuit composed of switches S1 to S2 and magnetic element 633, and a drive circuit 64.

[0070] exist Figure 13 In the illustrated embodiment, the energy storage circuit 624 includes, for example, a resonant slot composed of a resonant inductor Lr1, a magnetizing inductance Lm1 of the primary winding W11 of the transformer, a magnetizing inductance Lm2 of the primary winding W12 of the transformer, a resonant inductor Lr2, and a resonant capacitor Cr1, all connected in series. The first end of the resonant slot is coupled to the common terminal 223 of switching transistors Q1 and Q2, and the second end of the resonant slot is coupled to the common terminal 627 of switching transistors Q3 and Q4. The resonant inductor Lr1 can be formed, for example, by the leakage inductance of the primary winding W11 of the transformer, and the resonant inductor Lr2 can be formed, for example, by the leakage inductance of the primary winding W12 of the transformer. Those skilled in the art will understand that the specific circuit structure of the energy storage circuit 624 is not limited to this. Figure 13 The example shown.

[0071] The drive circuit 64 includes drivers 241-244, bootstrap capacitors Cb1-Cb3, and charging switch transistors Db1-Db3. Its specific circuit structure and... Figure 3 The illustrated embodiments are similar and will not be described in detail for simplicity. Figure 13 In the illustrated embodiment, the drive circuit 64 further includes a driver 401 that provides a drive signal Vg6 to the protection switch Q6, and a driver 402 that provides a drive signal Vg3 to the switch Q3. The driver 401 is coupled to both ends of the bootstrap capacitor Cb4, and the voltage Vd4 across the bootstrap capacitor Cb4 supplies power to the driver 401. In one embodiment, one end of the bootstrap capacitor Cb4 is coupled to voltage terminal 101, i.e., the source terminal of the protection switch Q6, and the other end of the bootstrap capacitor Cb4 is coupled to a charging circuit that charges the bootstrap capacitor Cb4, such as, but not limited to, a charging circuit for charging the bootstrap capacitor Cb4. Figure 13The charging switch Db4 and bootstrap capacitor Cb5 are shown. In another embodiment, the charging circuit for bootstrap capacitor Cb4 may also include a charge pump circuit, for example. Driver 402 is coupled to both ends of bootstrap capacitor Cb5, and the voltage Vd5 across bootstrap capacitor Cb5 powers driver 242. In one embodiment, one end of bootstrap capacitor Cb5 is coupled to the common terminal 627 of switches Q3 and Q4, and the other end of bootstrap capacitor Cb5 is coupled to bootstrap capacitor Cb6 through charging switch Db5. When protection switches Q6 and Q3 are turned on, bootstrap capacitor Cb5 charges bootstrap capacitor Cb4 through charging switch Db4. When the voltage across bootstrap capacitor Cb4 is insufficient to turn on protection switch Q6, the current charging bootstrap capacitor Cb4 flows through the parasitic diode of protection switch Q6 and switch Q3. The other end of bootstrap capacitor Cb5 is also coupled to a charging circuit for charging bootstrap capacitor Cb5, such as including but not limited to... Figure 13 The charging switch Q4 is shown as Db5, and the bootstrap capacitor Q3 is shown as Cb6. When switch Q4 is turned on, bootstrap capacitor Q3 is charged by charging switch Q4 through charging switch Q4. In another embodiment, the charging circuit for bootstrap capacitor Q3 may also include a charge pump circuit. In one embodiment, drivers 401 and 402 receive control signal PWMP2 and provide drive signals Vg6 and Vg3 respectively according to control signal PWMP2, so that protection switch Q6 and switch Q3 are synchronously turned on and off under the control of control signal PWMP2. Those skilled in the art will understand that there may be a delay between the synchronous turn-on and turn-off of protection switch Q6 and switch Q3.

[0072] exist Figure 13 In the illustrated embodiment, the driving circuit 64 further includes a driver 403 that provides a driving signal Vg4 to the switching transistor Q4 and a driver 404 that provides a driving signal Vgs2 to the switching transistor S2. The driver 403 is coupled to both ends of the bootstrap capacitor Cb6, and the voltage Vd6 across the bootstrap capacitor Cb6 powers the driver 403. In one embodiment, one end of the bootstrap capacitor Cb6 is coupled to the source terminal of the switching transistor Q4, and the other end of the bootstrap capacitor Cb6 is coupled to a charging circuit that charges the bootstrap capacitor Cb6, such as, but not limited to, a charging circuit. Figure 13 The charging switch Db6 and the supply voltage Vdrv are shown. In... Figure 13In the illustrated embodiment, the other end of the bootstrap capacitor Cb6 is simultaneously coupled to the bootstrap capacitor Cb6 via the charging switch Db5. When the switch S2 is turned on, the supply voltage Vdrv charges the bootstrap capacitor Cb6 through the charging switch Db6. In another embodiment, the charging circuit of the bootstrap capacitor Cb6 may, for example, include a charge pump circuit. In one embodiment, the driver 403 receives the control signal PWMP1 and provides a drive signal Vg4 according to the control signal PWMP1, causing the switch Q4 to be turned on and off under the control of the control signal PWMP1. In one embodiment, the control signals PWMP1 and PWMP2 are, for example, complementary in phase to control the complementary conduction of switches Q4 and Q3. Those skilled in the art will understand that a dead time may exist between the drive signals Vg4 and Vg3 to prevent switches Q4 and Q3 from being turned on simultaneously. The driver 404 receives the supply voltage Vdrv as its drive power supply. In one embodiment, capacitor Cdr2 is coupled between the supply voltage Vdrv and the reference ground GND, and its two ends are coupled to driver 404 to provide a stable power supply. In one embodiment, driver 404 receives control signal PWMS2 and provides drive signal Vgs2 according to control signal PWMS2 to drive switch S2 to turn on and off. Charging switches Db4 to Db6 may include, for example, diodes and controllable switches (such as MOSFETs, JFETs, BJTs, SJTs, IGBTs, etc.). In one embodiment, drive circuit 64 may be integrated on one or more drive chips.

[0073] Figure 14A This is a schematic diagram of a non-isolated switch converter 900 according to the present invention operating in a first switching mode. Figure 14A In the illustrated embodiment, in the first switching mode, switches Q1, Q4, and S1 are turned on, while switches Q6, Q3, Q2, and S2 are turned off. Because switch S1 is on, the supply voltage Vdrv charges the bootstrap capacitor Cb3 through the charging switch Db3, increasing the voltage across Cb3. Current flows back to reference ground GND and capacitor Cdr through switch S1. Because switch Q4 is on, bootstrap capacitor Cb6 is charged through the charging switch Db5, increasing the voltage across Cb5. Current flows back to bootstrap capacitor Cb6 through switch Q4.

[0074] exist Figure 14AIn the illustrated embodiment, when the voltage across the bootstrap capacitor Cb1 is insufficient to power the driver 241 and provide the drive signal Vg5, the protection switch Q5 remains off. Before the protection switch Q5 is turned on, the bootstrap capacitor Cb2 is charged by the charging switch Db1 when the switch Q1 is on, causing the voltage across the bootstrap capacitor Cb1 to rise. The current charging the bootstrap capacitor Cb1 flows back to the bootstrap capacitor Cb2 through the parasitic diode of the protection switch Q5 and the switch Q1. In one embodiment, the non-isolated switching converter 900 enters a second switching mode until the voltage across the bootstrap capacitor Cb1 is sufficient to drive the protection switch Q5 to turn on.

[0075] Figure 14B This is a schematic diagram of a non-isolated switch converter 900 according to the present invention operating in a second switching mode. Figure 14B In the illustrated embodiment, in the second switching mode, protection switches Q5, Q1, Q4, and S1 are turned on, while protection switches Q6, Q3, Q2, and S2 are turned off. Because switches Q1 and Q5 are on, the bootstrap capacitor Cb2 is charged through the charging switch Db1, increasing the voltage across Cb1. Current then flows back to Cb2 through protection switches Q5 and Q1.

[0076] Figure 15A This is a schematic diagram of a non-isolated switch converter 900 according to the present invention operating in a third switching mode. Figure 15A In the illustrated embodiment, in the third switching mode, switches Q3, Q2, and S2 are turned on, while switches Q5, Q1, Q4, and S1 are turned off. Because switch S2 is on, the supply voltage Vdrv charges the bootstrap capacitor Cb6 through the charging switch Db6, increasing the voltage across Cb6. Current flows back to reference ground GND and capacitor Cdr2 through switch S2. Because switch Q2 is on, bootstrap capacitor Cb3 is charged through the charging switch Db2, increasing the voltage across Cb2. Current flows back to bootstrap capacitor Cb3 through switch Q2.

[0077] exist Figure 15AIn the illustrated embodiment, when the voltage across the bootstrap capacitor Cb4 is insufficient to power the driver 401 and provide the drive signal Vg6, the protection switch Q6 remains off. Before the protection switch Q6 is turned on, the bootstrap capacitor Cb5 is charged by the charging switch Db4 when the switch Q3 is on, causing the voltage across Cb4 to rise. The current charging Cb4 flows back to the bootstrap capacitor Cb5 through the parasitic diode of the protection switch Q6 and the switch Q3. In one embodiment, the non-isolated switching converter 900 enters a fourth switching mode until the voltage across the bootstrap capacitor Cb4 is sufficient to drive the protection switch Q6 to turn on.

[0078] Figure 15B This is a schematic diagram of a non-isolated switch converter 900 according to the present invention operating in a fourth switching mode. Figure 15B In the illustrated embodiment, in the fourth switching mode, protection switches Q6, Q3, Q2, and S2 are turned on, while protection switches Q5, Q1, Q4, and S1 are turned off. Because switches Q3 and Q6 are on, the bootstrap capacitor Cb5 is charged through the charging switch Db4, increasing the voltage across Cb4. Current then flows back to Cb5 through protection switches Q6 and Q3.

[0079] Figure 16 This is a circuit diagram of a non-isolated switch converter 900A according to an embodiment of the present invention. Figure 16 In the illustrated embodiment, the energy storage circuit 624 includes energy storage capacitors Cr4 and Cr5. One end of energy storage capacitor Cr4 is coupled to the common terminal 223 of switching transistors Q1 and Q2, and the other end of energy storage capacitor Cr4 is coupled to the low-voltage side circuit through the fourth terminal 626 of the high-voltage side circuit, for example, coupled to the drain terminal of magnetic element 633 and switching transistor S1. One end of energy storage capacitor Cr5 is coupled to the common terminal 627 of switching transistors Q3 and Q4, and the other end of energy storage capacitor Cr5 is coupled to the low-voltage side circuit through the second terminal 622 of the high-voltage side circuit, for example, coupled to the drain terminal of magnetic element 633 and switching transistor S2. Figure 16 In the illustrated embodiment, magnetic element 633 includes magnetic elements L1 and L2. Magnetic elements L1 and L2 can be, for example, inductors or transformers. One end of magnetic element L1 is coupled to the second terminal 622 of the high-voltage side circuit and the drain terminal of the switching transistor S1. The other end of magnetic element L1 and one end of magnetic element L2 are coupled together to voltage terminal 103. The other end of magnetic element L2 is coupled to the fourth terminal 626 of the high-voltage side circuit and the drain terminal of the switching transistor S2.

[0080] Figure 17This is a circuit diagram of a non-isolated switching converter 1000 according to an embodiment of the present invention. Figure 17 In the illustrated embodiment, the driving circuit 74 includes a charging circuit 246 and a charging circuit 247. As previously described, the charging circuit 246 charges the bootstrap capacitors Cb1 and Cb2, which will not be repeated here.

[0081] Charging circuit 247 charges bootstrap capacitors Cb4 and Cb5. Charging circuit 247 is coupled to both ends of capacitor Cdr3 to receive a supply voltage Vdrv. Charging circuit 247 provides a supply voltage Vd4 across bootstrap capacitor Cb4 and a supply voltage Vd5 across bootstrap capacitor Cb5. In one embodiment, the supply voltage Vdrv charges bootstrap capacitor Cb5 through charging circuit 247. In one embodiment, charging circuit 247 includes a charging switch Sc2 coupled between bootstrap capacitors Cb4 and Cb5. When protection switches Q6 and Q3 are turned on, charging switch Sc2 is turned on, and bootstrap capacitor Cb5 charges bootstrap capacitor Cb4 through charging switch Sc2. In one embodiment, drive circuit 74 can be integrated on one or more drive chips. For example, but not limited to, drivers 241, 242, and charging circuit 246 are integrated on a single driver chip; drivers 401, 402, and charging circuit 247 are integrated on a single driver chip; drivers 243 and 244 are integrated on a single driver chip; and drivers 403 and 404 are integrated on a single driver chip.

[0082] Figure 18 This is a circuit diagram of a non-isolated switching converter 1100 according to an embodiment of the present invention. The non-isolated switching converter 1100 includes driver chips 111-116. Each driver chip includes a control input pin PWMH, a control input pin PWML, a power supply pin VCC, a reference ground pin RTN, a bootstrap pin BST, a switching pin SW, a drive output pin HG, and a drive output pin LG. The power supply pin VCC of each driver chip is coupled to the supply voltage Vdrv, and a coupling capacitor is connected between the power supply pin VCC and the reference ground pin RTN, such as... Figure 18 The capacitors C1 to C6 are shown. A bootstrap capacitor is connected between the bootstrap pin BST and the switch pin SW of each driver chip, as shown... Figure 18 The capacitors shown are Cb1 to Cb6. Each driver chip provides a drive signal at its drive output pin HG based on the control signal received at its control input pin PWMH, and provides a drive signal at its drive output pin LG based on the control signal received at its control input pin PWML.

[0083] In one embodiment, driver chip 111 receives control signal PWMP1 at its control input pin PWMH and provides drive signal Vg5 at its drive output pin HG. Driver chip 112 receives control signal PWMP1 at its control input pin PWMH and provides drive signal Vg1 at its drive output pin HG. When switching transistor Q1 and protection switching transistor Q5 are turned on, bootstrap capacitor Cb2 coupled between bootstrap pin BST and switching pin SW of driver chip 112 is charged by charging switching transistor Db1. Driver chip 113 receives control signal PWMP2 at its control input pin PWMH, receives control signal PWMS1 at its control input pin PWML, provides drive signal Vg2 at its drive output pin HG, and provides drive signal Vgs1 at its drive output pin LG. When switch Q2 is turned on, the bootstrap capacitor Cb3, coupled between the bootstrap pin BST and the switch pin SW of driver chip 113, charges the bootstrap capacitor Cb3, coupled between the bootstrap pin BST and the switch pin SW of driver chip 112, through the charging switch Db2. When switch S1 is turned on, the supply voltage Vdrv charges the bootstrap capacitor Cb3, coupled between the bootstrap pin BST and the switch pin SW of driver chip 113, through the internal circuitry of driver chip 113. In one embodiment, driver chip 111 and / or driver chip 112 further receive the control signal PWMS1 on their respective control input pin PWML, and output a drive signal to switch S1 (e.g., ...) on their respective drive output pin LG. Figure 18 (As shown by the dashed lines connecting to driver chip 111 and driver chip 112), to enhance the driving capability of switch S1.

[0084] In one embodiment, driver chip 114 receives control signal PWMP2 at its control input pin PWMH and provides drive signal Vg6 at its drive output pin HG. Driver chip 115 receives control signal PWMP2 at its control input pin PWMH and provides drive signal Vg3 at its drive output pin HG. When switching transistor Q3 and protection switching transistor Q6 are turned on, bootstrap capacitor Cb5 coupled between bootstrap pin BST and switching pin SW of driver chip 115 is charged by charging switching transistor Db4, which in turn charges bootstrap capacitor Cb4 coupled between bootstrap pin BST and switching pin SW of driver chip 114. Driver chip 116 receives control signal PWMP1 at its control input pin PWMH, receives control signal PWMS2 at its control input pin PWML, provides drive signal Vg4 at its drive output pin HG, and provides drive signal Vgs2 at its drive output pin LG. When switch Q4 is turned on, the bootstrap capacitor Cb6, coupled between the bootstrap pin BST and the switch pin SW of driver chip 116, charges the bootstrap capacitor Cb5, coupled between the bootstrap pin BST and the switch pin SW of driver chip 115, through the charging switch Db5. When switch S2 is turned on, the supply voltage Vdrv charges the bootstrap capacitor Cb6, coupled between the bootstrap pin BST and the switch pin SW of driver chip 116, through the internal circuitry of driver chip 116. In one embodiment, driver chip 114 and / or driver chip 115 further receive the control signal PWMS2 on their respective control input pin PWML, and output a drive signal to switch S2 (e.g., ...) on their respective drive output pin LG. Figure 18 (As shown by the dashed lines connecting to driver chip 114 and driver chip 115), to enhance the driving capability of switch S2.

[0085] Those skilled in the art will understand that the number and connections of driver chips 111-116 are not limited to Figure 18 The illustrated embodiment is an example. For example, it could also be one or more such embodiments. Figure 18 The shown combination of driver chips and other types of driver chips or driver circuits.

[0086] Figure 19 This is a circuit diagram of the driver chip 111 according to an embodiment of the present invention. The internal structures of driver chips 112-116 are similar to those of driver chip 111, and will not be described in detail for simplicity. Figure 19 As shown, the driver chip 111 includes a charging switch 912, a driver 913, and a driver 916 coupled between the power supply pin VCC and the bootstrap pin BST. The charging switch 912 may be, for example, a diode or other type of controllable switch.

[0087] exist Figure 19In the illustrated embodiment, the positive power supply terminal of driver 913 is coupled to the bootstrap pin BST, and the negative power supply terminal of driver 913 is coupled to the switch pin SW. The voltage between the bootstrap pin BST and the switch pin SW powers driver 913, meaning the bootstrap capacitor coupled between the bootstrap pin BST and the switch pin SW powers driver 913. Driver 913 provides a drive signal at drive output pin HG based on the control signal received at control input pin PWMH. In one embodiment, driver chip 111 further includes an undervoltage detection circuit 914 and a logic circuit 915. Undervoltage detection circuit 914 is coupled between bootstrap pin BST and switch pin SW, and provides an undervoltage signal UV based on whether the voltage between bootstrap pin BST and switch pin SW is below an undervoltage threshold. Logic circuit 915 is coupled to undervoltage detection circuit 914 and control input pin PWMH, and provides a control signal INH at its output based on the undervoltage signal UV and the control signal received at control input pin PWMH. Driver 913 is coupled to logic circuit 915 and generates a drive signal on drive output pin HG according to the control signal INH provided by logic circuit 915. When undervoltage detection circuit 914 detects that the voltage between bootstrap pin BST and switch pin SW is lower than the undervoltage threshold, it considers that driver 913 is underpowered and driver 913 stops outputting a valid drive signal on drive output pin HG.

[0088] exist Figure 19 In the illustrated embodiment, the positive power supply terminal of driver 916 is coupled to the power supply pin VCC, and the negative power supply terminal of driver 916 is coupled to the reference ground pin RTN. The supply voltage Vdrv between the power supply pin VCC and the reference ground pin RTN supplies power to driver 916. Driver 916 provides a drive signal at drive output pin LG based on the control signal received at control input pin PWML. In one embodiment, driver chip 111 further includes an undervoltage detection circuit 917 and a logic circuit 918. Undervoltage detection circuit 917 is coupled between power supply pin VCC and reference ground pin RTN, and provides an undervoltage signal UV2 based on whether the supply voltage Vdrv is lower than an undervoltage threshold. Logic circuit 918 is coupled to undervoltage detection circuit 917 and control input pin PWML, and provides a control signal INL at its output based on the undervoltage signal UV2 and the control signal received at control input pin PWML. Driver 916 is coupled to logic circuit 918, and generates a drive signal at drive output pin LG based on the control signal INL provided by logic circuit 918. When the undervoltage detection circuit 917 detects that the voltage between the power supply pin VCC and the reference ground pin RTN is lower than the undervoltage threshold, it considers that the power supply to the driver 916 is insufficient, and the driver 916 stops outputting a valid drive signal on the drive output pin LG.

[0089] Figure 20According to the embodiments of the present invention Figure 18 The waveform diagram 230 of the non-isolated switching converter 1100 is shown. From top to bottom, it shows the voltage VH, drive signal Vg6, drive signal Vg5, drive signal Vg3, drive signal Vg1, and the current IH flowing into the non-isolated switching converter 1100. Figure 23 As shown, the current IH is positive, and the non-isolated switching converter 1100 operates in forward mode. At time t1, drive signals Vg5 and Vg1 go low, turning off protection switches Q5 and Q1, while drive signals Vg6 and Vg3 go high, turning on protection switches Q6 and Q3. At this time, bootstrap capacitor Cb5 charges bootstrap capacitor Cb4. At time t2, drive signals Vg6 and Vg3 go low, turning off protection switches Q6 and Q3, while drive signals Vg5 and Vg1 go high, turning on protection switches Q6 and Q1. At this time, bootstrap capacitor Cb2 charges bootstrap capacitor Cb1. In one embodiment, a voltage level between a high threshold voltage (e.g., 2V) and a supply voltage (e.g., 3.3V) is a high voltage level, a voltage level between zero voltage (0V) and a low threshold voltage (e.g., 1V) is a low voltage level, and a voltage level between a high threshold voltage and a low threshold voltage is a medium voltage level.

[0090] Figure 21 This is a circuit diagram of a non-isolated switching converter 1200 according to an embodiment of the present invention. The non-isolated switching converter 1200 includes driver chips 81-84. Each driver chip includes a control input pin PWMH, a control input pin PWML, a power supply pin VCC, a reference ground pin RTN, a charge pump pin CN, a charge pump pin CP, a drive power supply pin LB, a drive power supply return pin LS, a drive power supply pin HB, a drive power supply return pin HS, a drive output pin HG, and a drive output pin LG. The power supply pin VCC of each driver chip is coupled to the supply voltage Vdrv, and a coupling capacitor is connected between the power supply pin VCC and the reference ground pin RTN, such as... Figure 21 Capacitors C11 to C14 are shown. A flying capacitor is connected between the charge pump pin CP and the charge pump pin CN of each driver chip, as shown... Figure 21 The capacitors C21 to C24 are shown. A bootstrap capacitor is coupled between the drive power supply pin LB and the drive power supply return pin LS of each driver chip, as shown... Figure 21 The capacitors C31 to C34 are shown. A bootstrap capacitor is coupled between the drive power supply pin HB and the drive power supply return pin HS of each driver chip, as shown... Figure 21The capacitors shown are C41 to C44. Each driver chip provides a drive signal at its drive output pin HG based on the control signal received at its control input pin PWMH, and provides a drive signal at its drive output pin LG based on the control signal received at its control input pin PWML.

[0091] In one embodiment, driver chip 81 receives control signal PWMP1 on both its control input pins PWMH and PWML, and provides drive signal Vg5 on its drive output pin HG and drive signal Vg1 on its drive output pin LG according to control signal PWMP1. The flying capacitor C21 coupled between charge pump pins CP and CN charges bootstrap capacitor C31 coupled between drive power supply pin LB and drive power supply return pin LS. When protection switch Q5 and switch Q1 are turned on, bootstrap capacitor C31 coupled between drive power supply pin LB and drive power supply return pin LS charges bootstrap capacitor C41 coupled between drive power supply pin HB and drive power supply return pin HS. Driver chip 82 receives control signal PWMP2 on its control input pin PWMH and provides drive signal Vg2 on its drive output pin HG according to control signal PWMP2; it also receives control signal PWMS1 on its control input pin PWML and provides drive signal Vgs1 on its drive output pin LG according to control signal PWMS1. The drive power supply return pin LS is coupled to reference ground GND, and the supply voltage Vdrv is directly transferred to the bootstrap capacitor C32. When the switch S1 is turned on, the bootstrap capacitor C32 charges the bootstrap capacitor C42 coupled between the drive power supply pin HB and the drive power supply return pin HS.

[0092] In one embodiment, driver chip 83 receives control signal PWMP2 on both its control input pins PWMH and PWML, and provides drive signal Vg6 on its drive output pin HG and drive signal Vg3 on its drive output pin LG according to control signal PWMP2. The flying capacitor C23 coupled between charge pump pins CP and CN charges bootstrap capacitor C33 coupled between drive power supply pin LB and drive power supply return pin LS. When protection switch Q6 and switch Q3 are turned on, bootstrap capacitor C33 coupled between drive power supply pin LB and drive power supply return pin LS charges bootstrap capacitor C43 coupled between drive power supply pin HB and drive power supply return pin HS. Driver chip 84 receives control signal PWMP1 on its control input pin PWMH and provides drive signal Vg4 on its drive output pin HG according to control signal PWMP1; it also receives control signal PWMS2 on its control input pin PWML and provides drive signal Vgs2 on its drive output pin LG according to control signal PWMS2. The drive power supply return pin LS is coupled to reference ground GND, and the supply voltage Vdrv is directly transferred to the bootstrap capacitor C34. When the switch S2 is turned on, the bootstrap capacitor C34 charges the bootstrap capacitor C44 coupled between the drive power supply pin HB and the drive power supply return pin HS.

[0093] Those skilled in the art will understand that the number and connections of driver chips 81-84 are not limited to Figure 21 The illustrated embodiment is an example. For example, it could also be one or more such embodiments. Figure 21 The shown combination of driver chips and other types of driver chips or driver circuits.

[0094] Figure 22 This is a circuit diagram of the driver chip 81 according to an embodiment of the present invention. The internal structures of driver chips 82-84 are similar to those of driver chip 81, and will not be described in detail for simplicity. Figure 22 As shown, the driver chip 81 includes a charge pump circuit composed of switching transistors 72-75 and an oscillation circuit 71, a driver 811, a driver 812, and a charging switch 816. The common terminal of switching transistors 72 and 73 is coupled to the charge pump pin CP, and the common terminal of switching transistors 74 and 75 is coupled to the charge pump pin CN.

[0095] exist Figure 22 In the illustrated embodiment, the positive power supply terminal of driver 811 is coupled to the drive power supply pin HB, and the negative power supply terminal of driver 811 is coupled to the drive power supply return pin HS. A bootstrap capacitor is coupled between the drive power supply pin HB and the drive power supply return pin HS. Figure 22(Not shown) provides power to driver 811. Driver 811 provides a drive signal at drive output pin HG based on the control signal received at control input pin PWMH. In one embodiment, driver chip 81 further includes undervoltage detection circuit 813 and logic circuit 817. Undervoltage detection circuit 813 is coupled between drive power supply pin HB and drive power return pin HS, and provides undervoltage signal UV2 based on whether the voltage between drive power supply pin HB and drive power return pin HS is lower than an undervoltage threshold. Logic circuit 817 is coupled to undervoltage detection circuit 813 and control input pin PWMH, and provides control signal INH1 at its output based on undervoltage signal UV2 and control signal received at control input pin PWMH. Driver 811 is coupled to logic circuit 817, and generates a drive signal at drive output pin HG based on control signal INH1 provided by logic circuit 817. When undervoltage detection circuit 813 detects that the voltage between drive power supply pin HB and drive power return pin HS is lower than the undervoltage threshold, it considers that driver 811 is underpowered, and driver 811 stops outputting a valid drive signal at drive output pin HG.

[0096] exist Figure 22 In the illustrated embodiment, the positive power supply terminal of driver 812 is coupled to the drive power supply pin LB, and the negative power supply terminal of driver 812 is coupled to the drive power supply return pin LS. A bootstrap capacitor is coupled between the drive power supply pin LB and the drive power supply return pin LS. Figure 22(Not shown) Power is supplied to driver 812. Driver 812 provides a drive signal at drive output pin LG based on the control signal received at control input pin PWML. In one embodiment, driver chip 81 further includes undervoltage detection circuit 814 and logic circuit 818. Undervoltage detection circuit 814 is coupled between drive power supply pin LB and drive power return pin LS, and provides undervoltage signal UV3 based on whether the voltage between drive power supply pin LB and drive power return pin LS is lower than an undervoltage threshold. Logic circuit 818 is coupled to undervoltage detection circuit 814 and control input pin PWML, and provides control signal INL1 at its output based on undervoltage signal UV3 and control signal received at control input pin PWML. Driver 812 is coupled to logic circuit 818, and generates a drive signal at drive output pin LG based on control signal INL1 provided by logic circuit 818. When undervoltage detection circuit 814 detects that the voltage between drive power supply pin LB and drive power return pin LS is lower than the undervoltage threshold, it considers that driver 812 is underpowered, and driver 812 stops outputting a valid drive signal at drive output pin LG. The charging switch 816 is coupled between the drive power supply pin HB and the drive power supply pin LB. The voltage between the drive power supply pin LB and the drive power supply pin LS can be transmitted through the charging switch 816 to the bootstrap capacitor coupled between the drive power supply pin HB and the drive power supply pin HS. In one embodiment, when the drive output pin LG outputs a drive signal to turn on the corresponding switch, the control circuit 815 controls the charging switch 816 to turn on.

[0097] Figure 23 This is a flowchart of a control method 26 for a non-isolated switching converter according to an embodiment of the present invention. Figure 23 In the illustrated embodiment, control method 26 includes steps S11 to S15.

[0098] In step S11, in response to the positive mode, the non-isolated switch converter receives a first voltage between a first voltage terminal and a first voltage return terminal, and provides a second voltage lower than the first voltage between a second voltage terminal and a second voltage return terminal.

[0099] In step S12, in response to the reverse mode, the non-isolated switch converter provides a first voltage between a first voltage terminal and a first voltage return terminal, and receives a second voltage between a second voltage terminal and a second voltage return terminal.

[0100] In step S13, the high-voltage side circuit is coupled to the first voltage terminal by means of a protection switch, wherein the high-voltage side circuit includes a first terminal, a second terminal, and at least two switches coupled in series between the first terminal and the second terminal.

[0101] In step S14, the non-isolated switch converter is coupled to a second voltage terminal via a low-voltage side circuit, the low-voltage side circuit including at least one switch coupled between a second terminal of the high-voltage side circuit and a second voltage return terminal.

[0102] In step S15, multiple drive signals are provided to drive multiple switching transistors in the non-isolated switching converter respectively.

[0103] It should be noted that the execution order of the steps in the flowchart above is not limited to... Figure 23 As shown, two consecutive function blocks can be executed simultaneously or in reverse order.

[0104] Although the invention has been described with reference to several exemplary embodiments, it should be understood that the terminology used is descriptive and exemplary, and not restrictive. Since the invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A non-isolated switch converter, comprising: First voltage terminal and first voltage return terminal; A second voltage terminal and a second voltage return terminal, wherein the second voltage return terminal is coupled to the first voltage return terminal; The first protection switch is coupled to the first voltage terminal; The high-voltage side circuit includes a first terminal, a second terminal, and a first switch and a second switch connected in series between the first terminal and the second terminal of the high-voltage side circuit. The first terminal of the high-voltage side circuit is coupled to a first voltage terminal through a first protection switch. The first protection switch and the first switch form a back-to-back switch pair. as well as The low-voltage side circuit is coupled to a second voltage terminal and a second voltage return terminal, and the low-voltage side circuit includes a third switching transistor coupled between the second terminal and the second voltage return terminal of the high-voltage side circuit; in In response to the positive mode, the non-isolated switching converter receives a first voltage between a first voltage terminal and a first voltage return terminal, and provides a second voltage lower than the first voltage between a second voltage terminal and a second voltage return terminal; as well as In response to the reverse mode, the non-isolated switching converter provides the first voltage between the first voltage terminal and the first voltage return terminal, and receives the second voltage between the second voltage terminal and the second voltage return terminal.

2. The non-isolated switch converter as described in claim 1, wherein... The first protection switch includes a source terminal, a drain terminal, and a control terminal, wherein the source terminal of the first protection switch is coupled to a first voltage terminal; The first switching transistor includes a source terminal, a drain terminal, and a control terminal, wherein the drain terminal of the first switching transistor is coupled to the drain terminal of the first protection switching transistor; The second switch includes a source terminal, a drain terminal, and a control terminal, wherein the drain terminal of the second switch is coupled to the source terminal of the first switch. as well as The third switch includes a source terminal, a drain terminal, and a control terminal, wherein the drain terminal of the third switch is coupled to the source terminal of the second switch, and the source terminal of the third switch is coupled to a reference ground.

3. The non-isolated switch converter as described in claim 2, further comprising: The driving circuit receives a first control signal and provides a first driving signal to the control terminal of the first protection switch according to the first control signal, provides a second driving signal to the control terminal of the first switch according to the first control signal, the driving circuit receives the second control signal and provides a third driving signal to the control terminal of the second switch according to the second control signal, and the driving circuit receives the third control signal and provides a fourth driving signal to the control terminal of the third switch according to the third control signal. in The driving circuit can be configured to control the first protection switch, the first switching transistor, and the third switching transistor to remain on, while controlling the second switching transistor to remain off; and The drive circuit can be configured to control the first protection switch, the first switch, and the third switch to remain off, while controlling the second switch to remain on.

4. The non-isolated switch converter as claimed in claim 1, further comprising: The first driver is configurable to provide a first drive signal to drive the first protection switch to turn on and off; A first capacitor includes a first terminal and a second terminal, the second terminal of the first capacitor being coupled to a first voltage terminal, and the first capacitor being configurable to power a first driver through a voltage between its first terminal and second terminal. The second driver can be configured to provide a second drive signal to drive the first switch to turn on and off; as well as The second capacitor includes a first terminal and a second terminal, the second terminal of the second capacitor being coupled to the common terminal of the first switch and the second switch, and the second capacitor being configurable to power the second driver through the voltage between its first terminal and the second terminal. in When the voltage across the first capacitor is insufficient to power the first driver and provide the first drive signal, the second capacitor charges the first capacitor when the first switch is turned on, and the charging current flows through the parasitic diode of the first protection switch and the first switch.

5. The non-isolated switch converter as claimed in claim 4, further comprising: The third driver can be configured to provide a third drive signal to drive the second switch to turn on and off; A third capacitor includes a first terminal and a second terminal, the second terminal of the third capacitor being coupled to a second terminal of a high-voltage side circuit, and the third capacitor being configurable to power a third driver through the voltage between its first and second terminals. as well as The fourth driver is configured to provide a fourth drive signal to drive the third switch to turn on and off, and the fourth driver is configured to receive a power supply voltage. in The first terminal of the third capacitor is coupled to the first terminal of the second capacitor via a second charging switch, and the third capacitor charges the second capacitor when the second switch is turned on; and When the third switch is turned on, the supply voltage charges the third capacitor.

6. The non-isolated switch converter as claimed in claim 4, further comprising: The charge pump circuit receives the power supply voltage; as well as A flying capacitor is coupled at both ends to a charge pump circuit, which can be configured to charge the flying capacitor and the flying capacitor can be configured to charge a second capacitor.

7. The non-isolated switch converter of claim 1, wherein the high-voltage side circuit further comprises: An energy storage circuit includes a first terminal and a second terminal, wherein the first terminal of the energy storage circuit is coupled to the common terminal of a first switching transistor and a second switching transistor, and the second terminal of the energy storage circuit is coupled to a low-voltage side circuit.

8. The non-isolated switch converter as claimed in claim 1, further comprising: The second protection switch is coupled to the first voltage terminal; in The high-voltage side circuit further includes: The third terminal, the fourth terminal, and the fourth and fifth switching transistors connected in series between the third and fourth terminals of the high-voltage side circuit, wherein the third terminal of the high-voltage side circuit is coupled to the first voltage terminal through the second protection switching transistor, and the fourth terminal of the high-voltage side circuit is coupled to the low-voltage side circuit. as well as An energy storage circuit includes a first terminal and a second terminal, wherein the first terminal of the energy storage circuit is coupled to a common terminal of a first switching transistor and a second switching transistor, and the second terminal of the energy storage circuit is coupled to a common terminal of a fourth switching transistor and a fifth switching transistor.

9. The non-isolated switch converter of claim 1, wherein the high-voltage side circuit further comprises: The third terminal, the fourth terminal, and the fourth and fifth switching transistors connected in series between the third and fourth terminals, wherein the third terminal of the high-voltage side circuit is coupled to the first voltage terminal through the first protection switching transistor, and the fourth terminal of the high-voltage side circuit is coupled to the low-voltage side circuit. as well as An energy storage circuit includes a first terminal and a second terminal, wherein the first terminal of the energy storage circuit is coupled to a common terminal of a first switching transistor and a second switching transistor, and the second terminal of the energy storage circuit is coupled to a common terminal of a fourth switching transistor and a fifth switching transistor.

10. A non-isolated switch converter, comprising: First voltage terminal and first voltage return terminal; A second voltage terminal and a second voltage return terminal, wherein the second voltage return terminal is coupled to the first voltage return terminal; The first protection switch is coupled to the first voltage terminal; The second protection switch is coupled to the first voltage terminal; The high-voltage side circuit includes a first terminal, a second terminal, a third terminal, a fourth terminal, a first switch and a second switch connected in series between the first and second terminals of the high-voltage side circuit, and a third switch and a fourth switch connected in series between the third and fourth terminals of the high-voltage side circuit. The first terminal of the high-voltage side circuit is coupled to a first voltage terminal through a first protection switch, and the third terminal of the high-voltage side circuit is coupled to the first voltage terminal through a second protection switch. The first protection switch and the first switch form a back-to-back switch pair, and the second protection switch and the third switch form a back-to-back switch pair. The low-voltage side circuit is coupled to a second voltage terminal and a second voltage return terminal. The low-voltage side circuit includes a fifth switch coupled between the second terminal and the second voltage return terminal of the high-voltage side circuit, and a sixth switch coupled between the fourth terminal and the second voltage return terminal of the high-voltage side circuit. as well as An energy storage circuit includes a first terminal and a second terminal, wherein the first terminal of the energy storage circuit is coupled to a common terminal of a first switching transistor and a second switching transistor, and the second terminal of the energy storage circuit is coupled to a common terminal of a third switching transistor and a fourth switching transistor. in In response to the positive mode, the non-isolated switch converter receives a first voltage between its first voltage terminal and a first voltage return terminal, and provides a second voltage lower than the first voltage between its second voltage terminal and the second voltage return terminal; as well as In response to the reverse mode, the non-isolated switching converter provides the first voltage between its first voltage terminal and the first voltage return terminal, and receives the second voltage between its second voltage terminal and the second voltage return terminal.

11. The non-isolated switch converter as claimed in claim 10, wherein: The non-isolated switchgear can be configured to control the first protection switch, the first switch, the fourth switch, and the fifth switch to remain on, while controlling the second protection switch, the second switch, the third switch, and the sixth switch to remain off; and The non-isolated switchgear can be configured to control the first protection switch, the first switch, the fourth switch, and the fifth switch to remain off, while controlling the second protection switch, the second switch, the third switch, and the sixth switch to remain on.

12. The non-isolated switch converter of claim 10, further comprising: The first driver is configured to provide a first drive signal to drive the first protection switch transistor; A first capacitor includes a first terminal and a second terminal, the second terminal of the first capacitor being coupled to a first voltage terminal, and the first capacitor being configurable to power a first driver through a voltage between its first terminal and second terminal. The second driver can be configured to provide a second drive signal to drive the first switching transistor; The second capacitor includes a first terminal and a second terminal, the second terminal of the second capacitor being coupled to the common terminal of the first switch and the second switch, and the second capacitor being configurable to power the second driver through the voltage between its first terminal and the second terminal. The third driver can be configured to provide a third drive signal to drive the second protection switch. A third capacitor includes a first terminal and a second terminal, the second terminal of the third capacitor being coupled to a first voltage terminal, and the third capacitor being configurable to power a third driver through a voltage between its first and second terminals. A fourth driver can be configured to provide a fourth drive signal to drive a third switching transistor; as well as A fourth capacitor includes a first terminal and a second terminal, the second terminal of the fourth capacitor being coupled to a common terminal of a third switch and a fourth switch, and the fourth capacitor being configurable to power a fourth driver through the voltage between its first and second terminals. in The first terminal of the second capacitor can be configured to be coupled to the first terminal of the first capacitor through a first charging switch, and the first terminal of the fourth capacitor can be configured to be coupled to the first terminal of the third capacitor through a second charging switch. When the first switch is turned on, the second capacitor charges the first capacitor through the first charging switch, and when the third switch is turned on, the fourth capacitor charges the third capacitor through the second charging switch.

13. The non-isolated switch converter of claim 10, further comprising a driver chip, the driver chip comprising: The control input pin can be configured to receive a first control signal; The drive output pin can be configured to provide a first drive signal to the first protection switch to drive the first protection switch. The switch pin is coupled to the first voltage terminal; The bootstrap pin can be configured to be coupled to the switch pin via a first capacitor; as well as A driver includes an input terminal, an output terminal, a positive power supply terminal, and a negative power supply terminal, wherein the input terminal of the driver is coupled to a control input pin, the output terminal of the driver is coupled to a drive output pin, the positive power supply terminal of the driver is coupled to a bootstrap pin, and the negative power supply terminal of the driver is coupled to a switch pin, wherein the first capacitor is used to power the driver. in When the voltage across the first capacitor is insufficient to power the driver and provide the first drive signal, the non-isolated switching converter charges the first capacitor when the first switching transistor is turned on. The current charging the first capacitor flows through the parasitic diode of the first protection switching transistor and the first switching transistor.

14. The non-isolated switch converter of claim 10, further comprising a driver chip, the driver chip comprising: A first control input pin and a second control input pin, wherein the first control input pin and the second control output pin can be configured to jointly receive a first control signal; The first drive output pin and the second drive output pin are provided by the drive chip. The first drive signal is provided on the first drive output pin and the second drive signal is provided on the second drive output pin according to the first control signal. The first drive signal is used to drive the first protection switch and the second drive signal is used to drive the first switch. The power supply pin can be configured to receive the power supply voltage; The reference ground pin can be configured to be coupled to a reference ground; The first charge pump pin can be configured to be coupled to one end of the flying capacitor; The second charge pump pin can be configured to be coupled to the other end of the flying capacitor; The first drive power supply pin can be configured to be coupled to one end of the first capacitor; The first drive power supply return pin can be configured to be coupled to the other end of the first capacitor and the first voltage terminal; The second drive power supply pin can be configured to be coupled to one end of the second capacitor; as well as The second drive power supply return pin can be configured to be coupled to the other end of the second capacitor and the common terminal of the first and second switches via a charging switch. in When the first switch is turned on, the second capacitor charges the first capacitor.

15. The non-isolated switch converter of claim 14, wherein the driver chip further comprises: A first driver includes an input terminal, an output terminal, a positive power supply terminal, and a negative power supply terminal. The input terminal of the first driver is coupled to a first control input pin, the output terminal of the first driver is coupled to a first drive output pin, the positive power supply terminal of the first driver is coupled to a first drive power supply pin, and the negative power supply terminal of the first driver is coupled to a first drive power supply return pin. A first capacitor coupled between the first drive power supply pin and the first drive power supply return pin is used to supply power to the first driver. as well as The second driver includes an input terminal, an output terminal, a positive power supply terminal, and a negative power supply terminal. The input terminal of the second driver is coupled to a second control input pin, the output terminal of the second driver is coupled to a second drive output pin, the positive power supply terminal of the second driver is coupled to a second drive power supply pin, and the negative power supply terminal of the second driver is coupled to a second drive power supply return pin. A second capacitor coupled between the second drive power supply pin and the second drive power supply return pin is used to power the second driver.

16. The non-isolated switch converter of claim 10, further comprising: The first driver chip can be configured to provide a first drive signal according to a first control signal to drive the first protection switch transistor; The second driver chip can be configured to provide a second driver signal according to the first control signal to drive the first switching transistor; The third driver chip can be configured to provide a third driver signal to drive the second switch transistor according to the second control signal, and to provide a fourth driver signal to drive the fifth switch transistor according to the third control signal. The fourth driver chip can be configured to provide a fifth drive signal based on the second control signal to drive the second protection switch transistor. The fifth driver chip can be configured to provide a sixth drive signal to drive the third switch based on the second control signal; as well as The sixth driver chip can be configured to provide a seventh driver signal to drive the fourth switch transistor according to the first control signal, and to provide an eighth driver signal to drive the sixth switch transistor according to the fourth control signal.

17. The non-isolated switch converter of claim 10, further comprising: The first driver chip is configured to provide a first drive signal to drive a first protection switch transistor according to a first control signal, and to provide a second drive signal to drive the first switch transistor according to the first control signal. The second driver chip can be configured to provide a third driver signal to drive the second switch transistor according to the second control signal, and to provide a fourth driver signal to drive the fifth switch transistor according to the third control signal. The third driver chip can be configured to provide a fifth driver signal according to the second control signal to drive the second protection switch transistor, and to provide a sixth driver signal according to the second control signal to drive the third switch transistor. as well as The fourth driver chip can be configured to provide a seventh driver signal to drive the fourth switch transistor according to the first control signal, and to provide an eighth driver signal to drive the sixth switch transistor according to the fifth control signal.

18. A control method for a non-isolated switching converter, comprising: In response to the positive mode, the non-isolated switching converter receives a first voltage between a first voltage terminal and a first voltage return terminal, and provides a second voltage lower than the first voltage between a second voltage terminal and a second voltage return terminal; In response to the reverse mode, the non-isolated switching converter provides the first voltage between a first voltage terminal and a first voltage return terminal, and receives the second voltage between a second voltage terminal and a second voltage return terminal; The high-voltage side circuit is coupled to the first voltage terminal by means of a protection switch. The high-voltage side circuit includes a first terminal, a second terminal, and a first switch and a second switch connected in series between the first terminal and the second terminal of the high-voltage side circuit. The protection switch and the first switch form a back-to-back switch pair. The non-isolated switching converter is coupled to a second voltage terminal via a low-voltage side circuit, the low-voltage side circuit including a third switching transistor coupled between a second terminal of the high-voltage side circuit and a second voltage return terminal. as well as A first drive signal for driving the protection switch is provided by a first driver, a second drive signal for driving the first switch is provided by a second driver, a third drive signal for driving the second switch is provided by a third driver, and a fourth drive signal for driving the third switch is provided by a fourth driver.

19. The control method of claim 18, further comprising: The first driver is powered by a first capacitor, and the first end of the first capacitor is coupled to a first voltage terminal. The second driver is powered by the second capacitor. The first end of the second capacitor is coupled to the second end of the first capacitor through a charging switch. The second end of the second capacitor is coupled to the common terminal of the first switch and the second switch. as well as When the voltage across the first capacitor is insufficient to power the first driver and provide the first drive signal, the second capacitor charges the first capacitor when the first switch is turned on, and the charging current of the first capacitor flows through the parasitic diode of the protection switch and the first switch.

20. The control method of claim 19, further comprising: The flying capacitor coupled to the charge pump circuit is charged through the charge pump circuit. as well as The flying capacitor charges the second capacitor via the charge pump circuit.

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