Drive control circuit and control method and charge pump circuit

Abstract

The present invention discloses a drive control circuit, a control method, and a charge pump circuit. The drive control circuit is used to drive a switching tube. The drive control circuit includes a first capacitor. The drive control circuit can couple to a first power supply and a second power supply. When the drive control circuit is in a first working state, the drive control circuit controls the first capacitor to couple to the first power supply and controls the first power supply to charge the first capacitor. When the drive control circuit is in a second working state, the drive control circuit controls the switching tube to couple to the second power supply and controls the second power supply to supply power to the switching tube. When the drive control circuit is in a third working state, the drive control circuit controls the first capacitor to couple to the control terminal of the switching tube and controls the first capacitor to supply power to the switching tube. The drive control circuit, control method, and charge pump circuit proposed in the present invention can reduce circuit energy consumption and improve circuit efficiency.

Description

Technical Field

[0001] The present invention belongs to the field of microelectronics technology and relates to a drive circuit, in particular to a drive control circuit and a control method as well as a charge pump circuit. Background Art

[0002] In motor drive technology, integrating power transistors and charge pumps within driver chips has become a trend as technology advances. The performance of the charge pump used to drive N-type power transistors directly affects the efficiency and overall cost of the motor drive.

[0003] The existing charge pump circuit scheme is as follows Figure 1 As shown, in the first phase, the first switch S1 and the third switch S3 are closed, and the first capacitor C1 is charged by the 5V LDO (voltage regulator). In the second phase, the second switch S2 and the fourth switch S4 are closed, and the lower plate of the first capacitor C1 is connected to the input power supply VM. Because the voltage across the first capacitor C1 cannot change suddenly, the voltage on the top plate of the first capacitor C1 is equal to VM + 5V, resulting in a charge pump voltage VCP = VM + 5V.

[0004] The existing technology requires two capacitors, and due to the continuous switching of the switch, it will cause relatively large power consumption and reduce the overall efficiency of the motor drive.

[0005] In view of this, there is an urgent need to design a new driving circuit to overcome at least some of the above-mentioned defects of the existing driving circuit. Summary of the Invention

[0006] The present invention provides a drive control circuit and a control method as well as a charge pump circuit, which can reduce circuit energy consumption and improve circuit efficiency.

[0007] In order to solve the above technical problems, according to one aspect of the present invention, the following technical solution is adopted:

[0008] A drive control circuit, the drive control circuit is used to drive a switch tube, the drive control circuit includes a first capacitor, and the drive control circuit can be coupled to a first power supply and a second power supply;

[0009] When the drive control circuit is in a first working state, the drive control circuit controls the first capacitor to couple to the first power supply, and controls the first power supply to charge the first capacitor;

[0010] When the drive control circuit is in the second working state, the drive control circuit controls the control terminal of the switch tube to be coupled to the second power supply, and controls the second power supply to supply power to the switch tube;

[0011] When the drive control circuit is in the third working state, the drive control circuit controls the first capacitor to couple to the control terminal of the switch tube, and controls the first capacitor to supply power to the switch tube.

[0012] As an embodiment of the present invention, when the source voltage of the switching tube is greater than or equal to a preset threshold, the driving control circuit is in a third working state, and the driving control circuit controls the first capacitor to supply power to the gate of the switching tube.

[0013] As an implementation manner of the present invention, the absolute value of the difference between the set threshold and the second power source is less than or equal to a preset difference.

[0014] As an embodiment of the present invention, the drive control circuit includes:

[0015] a charge pump circuit, comprising the first capacitor and a switch component, wherein the switch component is connected to the first capacitor;

[0016] A driving circuit, whose input end is coupled to the output end of the charge pump circuit, and the output end of the driving circuit is coupled to the control end of the switch tube; the driving circuit is used to selectively enable the charge pump circuit to power the switch tube according to a control signal.

[0017] As an embodiment of the present invention, the first power source is a voltage regulator, and the switch component is respectively coupled to the output terminal of the voltage regulator and the second power source;

[0018] The switch component is in a first state, and the output voltage of the voltage regulator charges the first capacitor;

[0019] The switch component is in the second state, and the second power supply supplies power to the gate of the switch tube;

[0020] When the switch component is in the third state, the first capacitor supplies power to the gate of the switch tube.

[0021] As an embodiment of the present invention, the switch assembly includes: a first diode, a second diode, a third diode, a first switch and a second switch;

[0022] The first end of the first capacitor is coupled to the cathode of the first diode and the anode of the second diode respectively, and the second end of the first capacitor is coupled to the first end of the first switch and the first end of the second switch respectively;

[0023] The anode of the first diode is coupled to the output end of the voltage regulator, the second end of the first switch is grounded, the second end of the second switch is coupled to the anode of the third diode and the output end of the second power supply, and the cathode of the second diode is coupled to the cathode of the third diode and forms the output end of the charge pump circuit.

[0024] As an embodiment of the present invention, the drive control circuit further includes:

[0025] a source detection circuit, wherein an input end of the source detection circuit is coupled to the source of the switch tube for detecting the source voltage of the switch tube; an output end of the source detection circuit is coupled to a switch control circuit;

[0026] A switch control circuit has an input end receiving the control signal and an output end of the source detection circuit, and an output end coupled to the charge pump circuit; the switch control circuit is used to send a switch control signal to the switch component of the charge pump circuit.

[0027] As an embodiment of the present invention, the charge pump circuit includes a first switch and a second switch; the switch control circuit receives the control signal, and the switch control circuit controls the opening and closing of the first switch and the second switch according to the control signal and the output signal of the source detection circuit;

[0028] When the source voltage is lower than a preset threshold, the drive control circuit is in a first working state; when the control signal is in a second state and the source voltage is lower than a preset threshold, the drive control circuit is in a second working state.

[0029] As an embodiment of the present invention, the switch assembly includes: a first diode, a second diode, a third diode, a first switch and a second switch;

[0030] The first end of the first capacitor is coupled to the cathode of the first diode and the anode of the second diode respectively, and the second end of the first capacitor is coupled to the first end of the first switch and the first end of the second switch respectively;

[0031] The anode of the first diode is coupled to the output voltage of the voltage regulator, the second end of the first switch is grounded, the second end of the second switch is coupled to the anode of the third diode and the second power supply, and the cathode of the second diode is coupled to the cathode of the third diode and forms the output end of the charge pump circuit;

[0032] When the control signal is in the first state, the switch tube is in the off state, the first switch is closed, the second switch is open, and the output voltage of the voltage regulator charges the first capacitor through the first diode; when the control signal is switched to the second state, the second power supply supplies power to the gate of the switch tube through the third diode, and the increase in the voltage of the gate of the switch tube drives the source of the switch tube to increase;

[0033] When the source detection circuit detects that the source voltage of the switching tube rises to the preset threshold, the first switch is disconnected and the second switch is turned on; the second end of the first capacitor is coupled to the second power supply, the voltage at the first end of the first capacitor rises, and the first capacitor supplies power to the gate of the switching tube, so that the gate voltage of the switching tube reaches the set value.

[0034] As an embodiment of the present invention, after the drive control circuit enters the third working state, the first capacitor is charged at every set time interval or when the voltage at one end of the first capacitor is lower than the second preset threshold.

[0035] As an embodiment of the present invention, the preset threshold is the second power supply or close to the second power supply; close to the second power supply means that the absolute value of the difference between the preset threshold and the second power supply is less than or equal to the preset difference.

[0036] As an implementation manner of the present invention, the drive control circuit includes the switch tube.

[0037] According to another aspect of the present invention, the following technical solution is adopted: a charge pump circuit, the charge pump circuit comprising: a first capacitor, a first diode, a second diode, a third diode, a first switch, and a second switch;

[0038] The first end of the first capacitor is coupled to the cathode of the first diode and the anode of the second diode respectively, and the second end of the first capacitor is coupled to the first end of the first switch and the first end of the second switch respectively;

[0039] The anode of the first diode is coupled to the first power supply, the second end of the first switch is grounded, the second end of the second switch is coupled to the anode of the third diode and the second power supply, and the cathode of the second diode is coupled to the cathode of the third diode and forms an output end of the charge pump circuit;

[0040] In a first time period, the first switch is turned on, the second switch is turned off, the first capacitor is coupled to the first power supply, the first power supply is controlled to charge the first capacitor, and the second power supply is coupled to the output end of the charge pump circuit;

[0041] During the second time period, the first switch is turned off, the second switch is turned on, and the second end of the first capacitor is coupled to the output end of the charge pump circuit.

[0042] According to another aspect of the present invention, the following technical solution is adopted: a drive control method, the drive control method comprising:

[0043] When the drive control circuit is in a first working state, controlling the first power supply to charge the first capacitor;

[0044] When the drive control circuit is in the second working state, controlling the second power supply to supply power to the switch tube;

[0045] When the drive control circuit is in the third working state, the first power supply is controlled to stop charging the first capacitor and raise the voltage of the first capacitor by an amount equal to the voltage value of the second power supply, and the first capacitor supplies power to the switching tube.

[0046] As an implementation manner of the present invention, when the source voltage of the switching tube is greater than or equal to a preset threshold, the first capacitor is controlled to supply power to the gate of the switching tube.

[0047] As an embodiment of the present invention, when the control signal is in the first state, the switch tube is in the off state, the first switch is controlled to be closed, and the output voltage of the regulator is used to charge the first capacitor through the first diode;

[0048] When the control signal is in the second state and the source voltage of the switch tube is less than a preset threshold, the second power supply is controlled to supply power to the gate of the switch tube through the third diode, so that the voltage of the gate of the switch tube increases, driving the source of the switch tube to increase;

[0049] When it is detected that the source voltage of the switching tube rises to a preset threshold, the first switch is controlled to be disconnected and the second switch is turned on; the second end of the first capacitor is coupled to the second power supply, the voltage at the first end of the first capacitor rises, and the first capacitor is controlled to supply power to the gate of the switching tube, so that the gate voltage of the switching tube reaches the set value.

[0050] As an embodiment of the present invention, the method further includes: after the driving control circuit enters the third working state, intermittently switching the states of the first switch and the second switch to charge the first capacitor at every set time interval or when the voltage at one end of the first capacitor is lower than a preset threshold.

[0051] The beneficial effects of the present invention are that the drive control circuit, control method and charge pump circuit proposed in the present invention can reduce circuit energy consumption and improve circuit efficiency.

[0052] In one usage scenario of the present invention, the present invention only needs one capacitor to complete the function of the charge pump, which saves device area, and because the switch does not need to be switched all the time, the power consumption is reduced. In the existing technical solution, when NM1 is turned on, the charge for the gate voltage to rise from 0 to VM+5V is provided by the charge pump capacitor C2. When the VM value is larger, the required capacitance value is larger. The present invention controls the start-up time of the charge pump by detecting the source voltage, thereby effectively reducing the required capacitor area. When NM1 is turned on, the NM1 gate is first charged by VM, that is, the charge for the NM1 gate voltage to rise from 0 to a value close to VM is provided by the power supply, rather than by the charge pump capacitor. The charge pump only needs to provide the charge for the gate voltage to rise from VM to VM+5V, thereby reducing the required capacitance value of the charge pump and saving chip area. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 Schematic diagram of a conventional motor drive circuit.

[0054] Figure 2 FIG. 4 is a circuit diagram of a drive control circuit in an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0056] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0057] The description in this section is only for several typical embodiments, and the present invention is not limited to the scope of the embodiments described. The same or similar existing technical means and some technical features of the embodiments are mutually replaced within the scope of the description and protection of the present invention.

[0058] The term "coupling" or "connection" as used in the specification includes both direct connection and indirect connection, such as connection through some active devices, passive devices or electrically conductive media; it may also include connection through other active devices or passive devices that are well known to those skilled in the art and can achieve the same or similar functional purposes, such as connection through circuits or components such as switches and follower circuits.

[0059] The present invention discloses a drive control circuit. Figure 2 FIG is a circuit diagram of a drive control circuit according to an embodiment of the present invention; Figure 2 The drive control circuit is used to drive the switch tube. The drive control circuit includes a first capacitor C3. The drive control circuit is coupled to the first power supply and the second power supply.

[0060] In one embodiment, the driving control circuit may include the switching tube, which may be a power tube, such as an N-type power tube, or other switching tubes.

[0061] When the driving control circuit is in a first working state, the driving control circuit controls the first capacitor C3 to couple to a first power source, and controls the first power source to charge the first capacitor C3.

[0062] When the drive control circuit is in the second operating state, the drive control circuit controls the control terminal of the switch NM1 to be coupled to the second power supply, thereby controlling the second power supply to power the switch NM1. In one embodiment, when the drive control circuit is in the second operating state, while controlling the second power supply to power the switch NM1, the drive control circuit can also control the first power supply to charge the first capacitor C3. In another embodiment, when the drive control circuit is in the second operating state, while controlling the second power supply to power the switch NM1, the first power supply does not charge the first capacitor C3.

[0063] When the drive control circuit is in the third operating state, the drive control circuit controls the first capacitor C3 to couple to the control terminal of the switching transistor, thereby controlling the first capacitor C3 to supply power to the switching transistor NM1. In one embodiment, after the drive control circuit enters the third operating state, the first capacitor C3 is charged at predetermined intervals or when the voltage at one terminal of the first capacitor C3 falls below a second predetermined threshold.

[0064] The first power source / the second power source may be a voltage source or a current source. The first power source and the second power source may be the same power source or different power sources.

[0065] In one embodiment of the present invention, the drive control circuit includes a charge pump circuit 100 and a drive circuit 200. The charge pump circuit 100 includes a first capacitor C3 and a switch component connected to the first capacitor C3. The input of the drive circuit 200 is coupled to the output of the charge pump circuit 100, and the output of the drive circuit 200 is coupled to the control terminal of the switch NM1. The drive circuit 200 is configured to selectively enable the charge pump circuit 100 to power the switch NM1 based on a control signal HS_ON. When the control signal HS_ON is in a first state, such as a low level, the output of the charge pump circuit 100 is disconnected from the gate of the switch NM1. When the control signal HS_ON is in a second state, such as a high level, the output of the charge pump circuit 100 is coupled to the gate of the switch NM1.

[0066] Please continue reading Figure 2In one embodiment of the present invention, the first power source is a first voltage source, which may be a voltage regulator (e.g., a linear voltage regulator (LDO)). The second power source may be a second voltage source. The switch component is coupled to the output terminal of the voltage regulator and the second voltage source VM, respectively. In a first state, the voltage regulator charges the first capacitor C3. In a second state, the second voltage source VM supplies power to the gate of the switch transistor NM1. In a third state, the first capacitor C3 supplies power to the gate of the switch transistor NM1.

[0067] like Figure 2 As shown, in one embodiment of the present invention, the switch component includes: a first diode D1, a second diode D2, a third diode D3, a first switch S5, and a second switch S6. The first end of the first capacitor C3 is coupled to the cathode of the first diode D1 and the anode of the second diode D2, respectively. The second end of the first capacitor C3 is coupled to the first end of the first switch S5 and the first end of the second switch S6, respectively. The anode of the first diode D1 is coupled to the output terminal of the voltage regulator, the second end of the first switch S5 is grounded, the second end of the second switch S6 is coupled to the anode of the third diode D3 and the output terminal of the second voltage source, and the cathode of the second diode D2 is coupled to the cathode of the third diode D3 and forms the output terminal of the charge pump circuit.

[0068] In addition, in one embodiment, the drive control circuit may further include: a source detection circuit 300 and a switch control circuit 400. The input of the source detection circuit 300 is coupled to the source of the switch transistor NM1 to detect the source voltage of the switch transistor NM1; the output of the source detection circuit 300 is coupled to the switch control circuit 400. The input of the switch control circuit 400 is coupled to a control signal HS_ON; the input of the switch control circuit 400 receives the control signal and the output of the source detection circuit, and the output of the switch control circuit 400 is coupled to the charge pump circuit 100. The switch control circuit 400 is configured to send a switch control signal to the switch components (e.g., the first switch S5 and the second switch S6) of the charge pump circuit 100 based on the control signal HS_ON.

[0069] In one embodiment of the present invention, when the control signal HS_ON is in a first state (e.g., the control signal HS_ON is low), the drive control circuit is in a first operating state. When the control signal switches from the first state to a second state (e.g., the control signal HS_ON is high), the drive control circuit switches from the first operating state to the second operating state. When the source voltage of the switch transistor NM1 is greater than or equal to a preset threshold, the drive control circuit is in a third operating state, and the drive control circuit 200 controls the first capacitor C3 to supply power to the gate of the switch transistor NM1. In one embodiment, the preset threshold is the second voltage source VM or is close to the second voltage source VM; close to the second voltage source means that the absolute value of the difference between the preset threshold and the second voltage source is less than or equal to the preset difference. In one embodiment, in the first working state and the second working state, the first switch S5 is closed and the second switch S6 is opened, and the output terminal voltage of the charge pump circuit 100 reflects the voltage of the second voltage source VM (VM-Vdiode), and the first working state and the second working state can be collectively referred to as the first time stage; in the third working state, the first switch S5 is opened and the second switch S6 is closed, and the output terminal voltage of the charge pump circuit 100 reflects the voltage of the upper plate of the first capacitor C3 (VM+6V-2Vdiode), which can be referred to as the second time stage of the charge pump circuit.

[0070] In one use scenario of the present invention, Figure 2 As shown, when the control signal HS_ON is low, the switch NM1 is off, the first switch S5 is closed, and the regulator output voltage (e.g., 6V) is fed through the first diode D1 to charge the first capacitor C3. When the control signal HS_ON is high, the gate of the switch NM1 is powered by the second voltage source VM via the third diode D3. The gate voltage of the switch NM1 rises, driving the source voltage upward. The source detection circuit 300 (source detection) monitors the source voltage of the switch NM1 in real time. When the source voltage rises to or near the value of the second voltage source VM, the first switch S5 is turned off and the second switch S6 is turned on. The lower plate of the first capacitor C3 is connected to the second voltage source VM, and the voltage on the upper plate of the first capacitor C3 rises to VM+6V-Vdiode. The gate of the switch NM1 is powered by the first capacitor C3, and the gate voltage of the switch NM1 can reach VM+6V-2Vdiode. Since the driver circuit 200 (Driver) and other circuits consume power, the voltage on the plate of the first capacitor C3 will slowly decrease. The switch control circuit can be used to control the first switch S5 and the second switch S6 at intervals to charge the first capacitor C3.

[0071] In one embodiment of the present invention, the switching transistor NM1 includes a parasitic capacitor CGS. Because the voltage on the top plate of the first capacitor C3 slowly decreases under a set state, the first switch S5 is turned on and the second switch S6 is turned off at set intervals or when the voltage at one end of the first capacitor C3 falls below a preset threshold. The output voltage 6V of the voltage regulator (or a second voltage source) charges the first capacitor C3. At this time, the gate voltage of the switching transistor NM1 is maintained by the parasitic capacitor CGS, and the second diode D2 prevents the charge from the parasitic capacitor CGS from flowing back into the first capacitor C3. After charging the first capacitor C3, the first switch S5 is turned off again, and the second switch S6 is turned on, continuing to supply the gate voltage of the switching transistor NM1 through the first capacitor C3.

[0072] In one embodiment, the drive control circuit may be used as a drive control circuit of a motor to drive and control the operation of the motor.

[0073] The present invention also discloses a charge pump circuit, wherein the charge pump is connected to a drive control circuit. Figure 2 The charge pump circuit 100 includes: a first capacitor C3, a first diode D1, a second diode D2, a third diode D3, a first switch S5, and a second switch S6. The first end of the first capacitor C3 is coupled to the cathode of the first diode D1 and the anode of the second diode D2, respectively. The second end of the first capacitor C3 is coupled to the first end of the first switch S5 and the first end of the second switch S6, respectively. The anode of the first diode D1 is coupled to a first voltage source, the first end of the first switch S5 is coupled to the output voltage of the regulator, the second end of the first switch S5 is grounded, the second end of the second switch S6 is coupled to the anode of the third diode D3 and the second voltage source, and the cathode of the second diode D2 is coupled to the cathode of the third diode D3 and forms the output end of the charge pump circuit.

[0074] During a first time period, the first switch S5 is turned on and the second switch S6 is turned off. The first capacitor C3 is coupled to the first voltage source, which controls the first voltage source to charge the first capacitor C3. The second voltage source is coupled to the output terminal of the charge pump circuit. During a second time period, the first switch S5 is turned off and the second switch S6 is turned on. The second terminal of the first capacitor C3 is coupled to the output terminal of the charge pump circuit. In one embodiment, the first time period includes a first operating state period and a second operating state period, and the second time period includes a third operating state period.

[0075] The present invention further discloses a drive control method, comprising: when a drive control circuit is in a first operating state, controlling a first voltage source to charge a first capacitor; when the drive control circuit is in a second operating state, controlling a second voltage source to power a switching transistor; and when the drive control circuit is in a third operating state, controlling the first voltage source to stop charging the first capacitor and increase the voltage of the first capacitor by an amount equal to the voltage value of the second voltage source, wherein the first capacitor powers the switching transistor. In one embodiment, when the source voltage of the switching transistor is greater than or equal to a preset threshold, controlling the first capacitor to power the gate of the switching transistor.

[0076] In one use scenario of the present invention, please refer to Figure 2 When the control signal HS_ON is low, the switch NM1 is off, controlling the first switch S5 to close, and controlling the output voltage of the voltage regulator LDO (e.g., 6V) to charge the first capacitor C3 through the first diode D1. When the control signal HS_ON is high, the gate of the switch NM1 is powered by the second voltage source VM via the third diode D3. The gate voltage of the switch NM1 rises, driving the source voltage to rise. The source detection circuit 300 (source detection) monitors the source voltage of the switch NM1 in real time. When the source voltage rises to or near the voltage of the second voltage source VM, the first switch S5 is turned off and the second switch S6 is turned on. The lower plate of the first capacitor C3 is connected to the second voltage source VM, and the voltage of the upper plate of the first capacitor C3 rises to VM+6V-Vdiode. The gate of the switch NM1 is powered by the first capacitor C3, and the gate voltage of the switch NM1 can reach VM+6V-2Vdiode. Due to the power consumption of the driving circuit 200 , the voltage on the upper plate of the first capacitor C3 will slowly decrease. At intervals, the switch control circuit can be used to control the first switch S5 and the second switch S6 to charge the first capacitor C3 .

[0077] In addition, the method may further include charging the first capacitor via the first voltage source at set intervals or when the voltage at one end of the first capacitor falls below a preset threshold, with the gate voltage of the switching transistor maintained via the parasitic capacitor CGS. When the first capacitor C3 is charged, the gate voltage of the switching transistor NM1 is maintained by the parasitic capacitor CGS, and the second diode D2 prevents charge from the parasitic capacitor CGS from flowing back into the first capacitor C3.

[0078] In summary, the drive control circuit and control method as well as the charge pump circuit proposed in the present invention can reduce circuit energy consumption and improve circuit efficiency.

[0079] In one usage scenario of the present invention, the present invention only needs one capacitor to complete the function of the charge pump, which saves device area, and because the switch does not need to be switched all the time, the power consumption is reduced. In the existing technical solution, when NM1 is turned on, the charge for the gate voltage to rise from 0 to VM+5V is provided by the charge pump capacitor C2. When the VM value is larger, the required capacitance value is larger. The present invention controls the start-up time of the charge pump by detecting the source voltage, thereby effectively reducing the required capacitor area. When NM1 is turned on, the NM1 gate is first powered by VM, that is, the charge for the NM1 gate voltage to rise from 0 to a value close to VM is provided by the power supply, rather than by the charge pump capacitor. The charge pump only needs to provide the charge for the gate voltage to rise from VM to VM+5V, thereby reducing the required capacitance value of the charge pump and saving chip area.

[0080] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0081] The description and application of the present invention here are illustrative and are not intended to limit the scope of the present invention to the above-described embodiments. The effects or advantages involved in the embodiments may not be embodied in the embodiments due to interference from various factors, and the description of the effects or advantages is not used to limit the embodiments. Variations and changes to the embodiments disclosed here are possible, and the replacement of the embodiments and various equivalent components are well known to those of ordinary skill in the art. It should be clear to those skilled in the art that the present invention can be implemented in other forms, structures, arrangements, proportions, and with other components, materials, and parts without departing from the spirit or essential characteristics of the present invention. Other variations and changes can be made to the embodiments disclosed here without departing from the scope and spirit of the present invention.

Claims

1. A drive control circuit, which is used to drive a switch tube, characterized in that: The drive control circuit includes a first capacitor, and the drive control circuit can be coupled to a first power supply and a second power supply; When the drive control circuit is in a first working state, the drive control circuit controls the first capacitor to couple to a first power supply, and controls the first power supply to charge the first capacitor; When the drive control circuit is in the second working state, the drive control circuit controls the control terminal of the switch tube to be coupled to the second power supply, and controls the second power supply to supply power to the switch tube; When the drive control circuit is in a third working state, the drive control circuit controls the first power supply to stop charging the first capacitor and raises the voltage of the first capacitor by an amount equal to the voltage value of the second power supply, controls the first capacitor to be coupled to the control terminal of the switching tube, and controls the first capacitor to supply power to the switching tube; When the control signal is in the first state, the drive control circuit is in the first working state; when the control signal is in the second state and the source voltage of the switch tube is lower than the preset threshold, the drive control circuit is in the second working state; when the source voltage of the switch tube is greater than or equal to the preset threshold, the drive control circuit is in the third working state.

2. The drive control circuit according to claim 1, wherein: When the source voltage of the switching tube is greater than or equal to a preset threshold, the driving control circuit controls the first capacitor to supply power to the gate of the switching tube.

3. The drive control circuit according to claim 2, wherein: An absolute value of a difference between the preset threshold and the second power source is less than or equal to a preset difference.

4. The drive control circuit according to any one of claims 1 to 3, characterized in that: The drive control circuit includes: a charge pump circuit, comprising the first capacitor and a switch component, wherein the switch component is connected to the first capacitor; A driving circuit, whose input end is coupled to the output end of the charge pump circuit, and the output end of the driving circuit is coupled to the control end of the switch tube; the driving circuit is used to selectively enable the charge pump circuit to power the switch tube according to a control signal.

5. The drive control circuit according to claim 4, wherein: The first power source is a voltage regulator, and the switch component is coupled to the output terminal of the voltage regulator and the second power source respectively; The switch component is in a first state, and the voltage regulator charges the first capacitor; The switch component is in the second state, and the second power supply supplies power to the gate of the switch tube; When the switch component is in the third state, the first capacitor supplies power to the gate of the switch tube.

6. The drive control circuit according to claim 4, wherein: The switch assembly includes: a first diode, a second diode, a third diode, a first switch and a second switch; The first end of the first capacitor is coupled to the cathode of the first diode and the anode of the second diode respectively, and the second end of the first capacitor is coupled to the first end of the first switch and the first end of the second switch respectively; The anode of the first diode is coupled to the output end of the voltage regulator, the second end of the first switch is grounded, the second end of the second switch is coupled to the anode of the third diode and the output end of the second power supply, and the cathode of the second diode is coupled to the cathode of the third diode and forms the output end of the charge pump circuit.

7. The drive control circuit according to claim 4, wherein: The drive control circuit further comprises: a source detection circuit, whose input terminal is coupled to the source of the switch tube and is used to detect the source voltage of the switch tube; A switch control circuit has an input end receiving the control signal and an output end of the source detection circuit, and an output end coupled to the charge pump circuit; the switch control circuit is used to send a switch control signal to the switch component of the charge pump circuit.

8. The drive control circuit according to claim 7, wherein: The charge pump circuit includes a first switch and a second switch; the switch control circuit receives the control signal, and controls the opening and closing of the first switch and the second switch according to the control signal and the output signal of the source detection circuit.

9. The drive control circuit according to claim 7, wherein: The switch assembly includes: a first diode, a second diode, a third diode, a first switch and a second switch; The first end of the first capacitor is coupled to the cathode of the first diode and the anode of the second diode respectively, and the second end of the first capacitor is coupled to the first end of the first switch and the first end of the second switch respectively; The anode of the first diode is coupled to the output voltage of the voltage regulator, the second end of the first switch is grounded, the second end of the second switch is coupled to the anode of the third diode and the second power supply, and the cathode of the second diode is coupled to the cathode of the third diode and forms the output end of the charge pump circuit; When the control signal is in the first state, the switch tube is in the off state, the first switch is closed, the second switch is open, and the output voltage of the voltage regulator charges the first capacitor through the first diode; when the control signal is switched to the second state, the second power supply supplies power to the gate of the switch tube through the third diode, and the increase in the voltage of the gate of the switch tube drives the source of the switch tube to increase; When the source detection circuit detects that the source voltage of the switching tube rises to the preset threshold, the first switch is disconnected and the second switch is turned on; the second end of the first capacitor is coupled to the second power supply, the voltage at the first end of the first capacitor rises, and the first capacitor supplies power to the gate of the switching tube, so that the gate voltage of the switching tube reaches the set value.

10. The drive control circuit according to any one of claims 1 to 3, characterized in that: After entering the third working state, the first capacitor is charged at every set time interval or when the voltage at one end of the first capacitor is lower than the second preset threshold.

11. The drive control circuit according to any one of claims 1 to 3, characterized in that: The driving control circuit includes the switching tube.

12. A charge pump circuit, implementing the drive control circuit according to claim 1, characterized in that: The charge pump circuit includes: a first capacitor, a first diode, a second diode, a third diode, a first switch and a second switch; The first end of the first capacitor is coupled to the cathode of the first diode and the anode of the second diode respectively, and the second end of the first capacitor is coupled to the first end of the first switch and the first end of the second switch respectively; The anode of the first diode is coupled to the first power supply, the second end of the first switch is grounded, the second end of the second switch is coupled to the anode of the third diode and the second power supply, and the cathode of the second diode is coupled to the cathode of the third diode and forms an output end of the charge pump circuit; In a first time period, the first switch is turned on, the second switch is turned off, the first capacitor is coupled to the first power supply, the first power supply is controlled to charge the first capacitor, and the second power supply is coupled to the output end of the charge pump circuit; In the second time period, the first switch is turned off, the second switch is turned on, and the second end of the first capacitor is coupled to the output end of the charge pump circuit.

13. A drive control method, characterized in that: The drive control method includes: When the drive control circuit is in a first working state, controlling the first power supply to charge the first capacitor; When the drive control circuit is in the second working state, controlling the second power supply to supply power to the switch tube; When the drive control circuit is in the third working state, the first power supply is controlled to stop charging the first capacitor and to increase the voltage of the first capacitor by an amount equal to the voltage value of the second power supply, and the first capacitor supplies power to the switching tube; When the control signal is in the first state, the drive control circuit is in the first working state; when the control signal is in the second state and the source voltage of the switch tube is lower than the preset threshold, the drive control circuit is in the second working state; when the source voltage of the switch tube is greater than or equal to the preset threshold, the drive control circuit is in the third working state.

14. The driving control method according to claim 13, wherein: When the control signal is in the first state, the switch tube is in the off state, the first switch is controlled to be closed, and the output voltage of the voltage regulator is used to charge the first capacitor through the first diode; When the control signal is in the second state and the source voltage of the switch tube is less than a preset threshold, the second power supply is controlled to supply power to the gate of the switch tube through the third diode, so that the voltage of the gate of the switch tube increases, driving the source of the switch tube to increase; When it is detected that the source voltage of the switching tube rises to a preset threshold, the first switch is controlled to be disconnected and the second switch is turned on; the second end of the first capacitor is coupled to the second power supply, the voltage at the first end of the first capacitor rises, and the first capacitor is controlled to supply power to the gate of the switching tube, so that the gate voltage of the switching tube reaches the set value.

15. The driving control method according to claim 14, characterized in that: The method further includes: after the drive control circuit enters the third working state, intermittently switching the states of the first switch and the second switch at every set time interval or when the voltage at one end of the first capacitor is lower than a preset threshold to charge the first capacitor.

Images