Drive control circuit and drive control method based on magnetic field intensity tracking

Abstract

The invention discloses a driving control circuit and a driving control method based on magnetic field intensity tracking. The driving control circuit comprises a driving circuit, a magnetic field tracking circuit and a control circuit, a driving output end of the driving circuit is connected with a first comparison input end of the magnetic field tracking circuit, a driving input end of the driving circuit is connected with a driving output end of the control circuit, and a magnetic field tracking signal output end of the magnetic field tracking circuit is connected with a magnetic field tracking signal input end of the control circuit; the second comparison input end of the magnetic field tracking circuit is connected with the battery anode. According to the drive control circuit based on magnetic field intensity tracking, the shock waves are output by the drive circuit through electromagnetic conversion, the shock waves are subjected to magnetic field tracking through the magnetic field tracking circuit, the magnetic field tracking signals are output, and the control circuit correspondingly controls the drive control signals to be periodically output according to the magnetic field tracking signals; and the switching loss of the MOS tube in the driving circuit is reduced, so that the calorific value of the MOS tube is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the field of circuit technology, and in particular to a drive control circuit and a drive control method based on magnetic field intensity tracking. Background Art

[0002] When using MOS tubes to drive inductive loads, the traditional approach is to control the chip (such as MCU) to output a driving signal with a fixed frequency and a variable duty cycle to drive the MOS tube, thereby achieving the purpose of controlling the output power; however, this control method does not take into account the amount of heat generated by the MOS tube, and simply adds a large heat sink to solve the problem of MOS tube temperature rise when the MOS tube needs to be cooled. However, many products do not have enough space to set up heat sinks due to structural size limitations. At this time, the heat accumulation cannot be quickly dissipated, resulting in a decrease in product performance. Therefore, the existing technical method based on the MOS tube drive control technology has the problem of excessive heat generation of the MOS tube. Summary of the invention

[0003] The embodiments of the present invention provide a driving control circuit and a driving control method based on magnetic field strength tracking, aiming to solve the problem of excessive heat generation of MOS tubes in the driving control technology based on MOS tubes in the prior art methods.

[0004] In a first aspect, an embodiment of the present invention provides a drive control circuit based on magnetic field intensity tracking, wherein the drive control circuit includes a drive circuit, a magnetic field tracking circuit and a control circuit;

[0005] The driving output terminal of the driving circuit is connected to the first comparison input terminal of the magnetic field tracking circuit, the driving input terminal of the driving circuit is connected to the driving output terminal of the control circuit, the magnetic field tracking signal output terminal of the magnetic field tracking circuit is connected to the magnetic field tracking signal input terminal of the control circuit; the second comparison input terminal of the magnetic field tracking circuit is connected to the positive pole of the battery.

[0006] In a second aspect, an embodiment of the present invention further provides a drive control method based on magnetic field strength tracking, wherein the drive control method is applied to the drive control circuit based on magnetic field strength tracking as described in the first aspect, and the drive control method includes:

[0007] If the control circuit receives a drive control instruction, the control circuit outputs a drive control signal to the drive circuit through a drive output terminal; the drive control signal is a rectangular square wave;

[0008] The driving circuit performs electromagnetic conversion according to the received driving control signal and outputs an oscillation wave from the driving output end; the starting time point of the oscillation wave is the starting time point of the low level in the rectangular square wave, and the signal strength of the oscillation wave is positively correlated with the magnetic field strength;

[0009] The magnetic field tracking circuit receives the oscillation wave and performs magnetic field tracking to output a magnetic field tracking signal through a magnetic field tracking signal output terminal;

[0010] The control circuit determines whether the received magnetic field tracking signal is at a low level; when the magnetic field is weakest, the magnetic field tracking signal is at a low level;

[0011] If the control circuit determines that the magnetic field tracking signal is at a low level, the process returns to the step of outputting the driving control signal to the driving circuit through the driving output terminal.

[0012] The embodiment of the present invention provides a driving control circuit and driving control method based on magnetic field intensity tracking, the driving control circuit includes a driving circuit, a magnetic field tracking circuit and a control circuit; the driving output end of the driving circuit is connected to the first comparison input end of the magnetic field tracking circuit, the driving input end of the driving circuit is connected to the driving output end of the control circuit, the magnetic field tracking signal output end of the magnetic field tracking circuit is connected to the magnetic field tracking signal input end of the control circuit; the second comparison input end of the magnetic field tracking circuit is connected to the positive pole of the battery. The above-mentioned driving control circuit based on magnetic field intensity tracking, through electromagnetic conversion and the driving circuit outputs an oscillation wave, the magnetic field tracking circuit tracks the oscillation wave in the magnetic field and outputs a magnetic field tracking signal, and the control circuit controls the driving control signal to output periodically according to the magnetic field tracking signal; the switching loss of the MOS tube in the driving circuit is reduced, thereby greatly reducing the heat generated by the MOS tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0014] Figure 1 An overall circuit structure diagram of a drive control circuit based on magnetic field intensity tracking provided by an embodiment of the present invention;

[0015] Figure 2 A partial circuit structure diagram of a drive control circuit based on magnetic field intensity tracking provided by an embodiment of the present invention;

[0016] Figure 3Another partial circuit structure diagram of a drive control circuit based on magnetic field intensity tracking provided by an embodiment of the present invention;

[0017] Figure 4 Another partial circuit structure diagram of a drive control circuit based on magnetic field intensity tracking provided by an embodiment of the present invention;

[0018] Figure 5 A method flow chart of a drive control method based on magnetic field intensity tracking provided by an embodiment of the present invention;

[0019] Figure 6 This is an application effect diagram of the drive control method based on magnetic field intensity tracking provided by an embodiment of the present invention.

[0020] Figure symbols: S1, driving circuit; S2, magnetic field tracking circuit; S3, control circuit; R1, first resistor; Q1, first MOS tube; C1, first capacitor; L1, first inductor; R2, second resistor; S21, voltage reference circuit; S22, magnetic field strength identification circuit; U3, comparator; S23, power supply filter circuit; S24, filter output circuit; R6, sixth resistor; R11, tenth resistor; C12, twelfth capacitor; R7, seventh resistor; R11, eleventh resistor; C10, tenth capacitor; R9, ninth resistor; C11, eleventh capacitor; C6, sixth capacitor; C8, eighth capacitor; C3, third capacitor; R26, twenty-sixth resistor. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0023] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0024] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0025] See also Figures 1 to 4 As shown in the figure, an embodiment of the present application discloses a driving control circuit based on magnetic field intensity tracking, which includes a driving circuit, a magnetic field tracking circuit and a control circuit; the driving output end of the driving circuit is connected to the first comparison input end of the magnetic field tracking circuit, the driving input end of the driving circuit is connected to the driving output end of the control circuit, and the magnetic field tracking signal output end of the magnetic field tracking circuit is connected to the magnetic field tracking signal input end of the control circuit; the second comparison input end of the magnetic field tracking circuit is connected to the positive pole of the battery; the driving circuit is used to perform electromagnetic conversion according to the driving control signal input by the driving input end and output an oscillation wave from the driving output end; the magnetic field tracking circuit performs magnetic field tracking on the oscillation wave to output a magnetic field tracking signal through the magnetic field tracking signal output end; the control circuit controls the driving control signal to output periodically according to the magnetic field tracking signal.

[0026] The connection relationship between the driving circuit, magnetic field tracking circuit and control circuit is as follows: Figure 1 As shown. The driving circuit receives the driving control signal from the control circuit, and outputs the oscillation wave from its driving output end after electromagnetic conversion; the magnetic field tracking circuit tracks the oscillation wave in the magnetic field to obtain the magnetic field tracking signal, and the magnetic field tracking signal is output to the control circuit from its magnetic field tracking signal output end, and the control circuit periodically outputs the driving control signal corresponding to the magnetic field tracking signal. Through the magnetic field tracking method, the time point when the magnetic field is weakest corresponds to the first MOS tube in the control driving circuit being turned on, so as to reduce the switching loss of the first MOS tube and greatly reduce the heat generation. When the above-mentioned driving control circuit is used in some products with relatively compact internal space, there is no need to set a large-size heat sink on the first MOS tube, that is, the above-mentioned driving control circuit can be suitable for products with limited internal space.

[0027] In a more specific embodiment, Figure 2As shown, the driving circuit includes a first resistor, a first MOS tube, a first capacitor and a first inductor; one end of the first resistor serves as the driving input end of the driving circuit, the other end of the first resistor is connected to the gate of the first MOS tube, and the source of the first MOS tube is grounded; the drain of the first MOS tube is connected to one end of the first capacitor and one end of the first inductor, and the connection point serves as the driving output end of the driving circuit; the other end of the first capacitor and the other end of the first inductor are both connected to the positive electrode of the battery. Specifically, the driving circuit also includes a second resistor, which is arranged in parallel between the gate of the first MOS tube and the grounding end.

[0028] The driving circuit is a MOS tube driving an inductive load circuit, which is mainly composed of a first resistor, a first MOS tube, a first capacitor and a first inductor, wherein the first inductor and the first capacitor form an electric energy conversion unit, which converts electric energy into magnetic energy. The conduction frequency and conduction duty cycle of the first MOS tube control the amount of energy absorbed by the electric energy conversion unit. The first resistor is used for current limiting.

[0029] In a more specific embodiment, Figure 3 As shown, the magnetic field tracking circuit includes a voltage reference circuit, a magnetic field strength identification circuit, a comparator, a power supply filter circuit and a filter output circuit; one end of the voltage reference circuit serves as the second comparison input end of the magnetic field tracking circuit, and the other end of the voltage reference circuit is connected to the second input end of the comparator; one end of the magnetic field strength identification circuit serves as the second comparison input end of the magnetic field tracking circuit, and the other end of the magnetic field strength identification circuit is connected to the first input end of the comparator; one end of the power supply filter circuit is grounded, and the other end is simultaneously connected to the voltage-stabilized power supply and the power input end of the comparator; the ground end of the comparator is grounded; the output end of the comparator is connected to the input end of the filter output circuit, and the output end of the filter output circuit serves as the magnetic field tracking signal output end of the magnetic field tracking circuit. Specifically, the voltage reference circuit includes a sixth resistor, a tenth resistor and a twelfth capacitor; one end of the sixth resistor is connected to the positive electrode of the battery, and the other end of the sixth resistor is connected to one end of the tenth resistor, one end of the twelfth capacitor and the second input end of the comparator; the other end of the tenth resistor and the other end of the twelfth capacitor are grounded. The magnetic field strength identification circuit includes a seventh resistor, an eleventh resistor and a tenth capacitor; one end of the seventh resistor is connected to the driving output end of the driving circuit; the other end of the seventh resistor is connected to the first input end of the comparator, one end of the eleventh resistor and one end of the tenth capacitor; the other end of the eleventh resistor and the other end of the tenth capacitor are grounded. One end of the twenty-sixth resistor is connected to the output end of the comparator, and the other end is connected to the voltage-stabilized power supply.

[0030] In a more specific embodiment, the filter output circuit includes a ninth resistor and an eleventh capacitor; one end of the ninth resistor is connected to the output end of the comparator; the other end of the ninth resistor is connected to one end of the eleventh capacitor, and the connection point is connected to the magnetic field tracking signal input end of the control circuit; the other end of the eleventh capacitor is grounded. Wherein, the power supply filter circuit includes a sixth capacitor; one end of the sixth capacitor is grounded, and the other end is simultaneously connected to the regulated power supply and the power input end of the comparator. More specifically, the magnetic field tracking circuit also includes an eighth capacitor; the eighth capacitor is arranged in parallel between the first input end and the second input end of the comparator.

[0031] The magnetic field tracking circuit is composed of a voltage reference circuit, a magnetic field strength identification circuit, a comparator, a power supply filter circuit and a filter output circuit. Among them, the voltage reference circuit is composed of the sixth resistor, the tenth resistor and the twelfth capacitor, which is used to connect to the positive pole of the battery and output the reference voltage to the comparator; the magnetic field strength identification circuit is composed of the seventh resistor, the eleventh resistor and the tenth capacitor, which is used to receive the oscillation wave output by the drive circuit and transmit it to the comparator accordingly. The power supply filter circuit is composed of the sixth capacitor, which is used to filter out the clutter of the voltage-stabilized power supply. The filter output circuit is composed of the ninth resistor and the eleventh capacitor, which is used to filter the comparison signal output by the comparator to obtain a magnetic field tracking signal. Among them, the eighth capacitor is used for high-frequency filtering. The voltage of the voltage-stabilized power supply is 5V.

[0032] like Figure 4 As shown, the control circuit is composed of a control chip and a third capacitor, wherein the second pin of the control chip is connected to one end of the third capacitor and grounded, and the twentieth pin of the control chip is connected to a voltage-stabilized power supply; the sixteenth pin of the control chip serves as a drive output end of the control circuit, and the nineteenth pin of the control chip serves as a magnetic field tracking signal input end of the control circuit.

[0033] The embodiment of the present invention further provides a driving control method based on magnetic field strength tracking, wherein the driving control method is applied to the driving control circuit based on magnetic field strength tracking as described in the above embodiment. Figure 5 , as shown in the figure, the driving control method includes steps S110 to S150.

[0034] S110: If the control circuit receives a drive control instruction, the control circuit outputs a drive control signal to the drive circuit through a drive output terminal.

[0035] If the control circuit receives the drive control instruction, the control circuit outputs the drive control signal to the drive circuit through the drive output terminal. The drive control signal is a rectangular square wave. The user can input the drive control instruction to the control circuit, and after the control circuit receives the drive control instruction, it outputs the drive control signal to the drive circuit through the drive output terminal. Figure 6 The rectangular square wave shown, Figure 6 The vertical axis V represents the voltage value of the electric signal, and the horizontal axis t represents time.

[0036] S120, the driving circuit performs electromagnetic conversion according to the received driving control signal and outputs an oscillation wave from the driving output terminal.

[0037] The driving circuit performs electromagnetic conversion according to the received driving control signal and outputs an oscillation wave from the driving output end. The starting time point of the oscillation wave is the starting time point of the low level in the rectangular square wave, and the signal strength of the oscillation wave is positively correlated with the magnetic field strength. The driving circuit performs electromagnetic conversion on the electric energy output from the positive electrode of the battery according to the received driving control signal, and outputs an oscillation wave from the driving output end; Figure 6 As shown in the figure, the waveform of the oscillation wave is an arc, and the starting time point of the oscillation wave is the starting time point of the low level in the rectangular square wave, that is, the oscillation wave begins to be generated when the voltage in the rectangular square wave drops to a low level. Figure 6 In ABC, the signal strength of the oscillation wave is positively correlated with the magnetic field strength generated by the power conversion unit, that is, the greater the magnetic field strength, the greater the signal strength (voltage value) of the sine wave. When the oscillation wave resonates to point B, the magnetic field strength is the strongest and the energy of the oscillation wave is the largest; when the oscillation wave resonates to point C, the magnetic field is the weakest and the energy of the oscillation wave is the smallest.

[0038] S130, the magnetic field tracking circuit receives the oscillation wave and performs magnetic field tracking to output a magnetic field tracking signal through a magnetic field tracking signal output terminal.

[0039] The magnetic field tracking circuit receives the oscillation wave and performs magnetic field tracking to output a magnetic field tracking signal through the magnetic field tracking signal output terminal. The magnetic field tracking circuit performs magnetic field tracking. Specifically, the input signal generated by the oscillation wave is input by the first input terminal of the comparator, and the reference voltage signal generated by the positive electrode of the battery is input by the second input terminal of the comparator. The comparator can compare the voltage values ​​of the first input terminal and the second input terminal, and output a comparison signal from its output terminal. The comparison signal is filtered and used as the magnetic field tracking signal.

[0040] S140, the control circuit determines whether the received magnetic field tracking signal is at a low level; when the magnetic field is weakest, the magnetic field tracking signal is at a low level.

[0041] The control circuit determines whether the received magnetic field tracking signal is at a low level; when the magnetic field is weakest, the magnetic field tracking signal is at a low level. The magnetic field tracking signal is output to the control circuit, and the control circuit determines whether the magnetic field tracking signal is at a low level. When the magnetic field strength is weakest, the magnetic field tracking signal obtained is at a low level.

[0042] S150: If the control circuit determines that the magnetic field tracking signal is at a low level, the process returns to the step of outputting the driving control signal to the driving circuit through the driving output terminal.

[0043] If the control circuit determines that the magnetic field tracking signal is at a low level, the process returns to the step of outputting the drive control signal to the drive circuit through the drive output terminal, and this process also returns to step S110; at this time, the control circuit outputs a new set of drive control signals, the first section of the new drive control signal is at a high level and the second section is at a low level. If the control circuit receives a termination drive instruction, the above-mentioned cyclic drive process is terminated.

[0044] In the driving control circuit and driving control method based on magnetic field intensity tracking provided in the embodiment of the present invention, the driving control circuit includes a driving circuit, a magnetic field tracking circuit and a control circuit; the driving output terminal of the driving circuit is connected to the first comparison input terminal of the magnetic field tracking circuit, the driving input terminal of the driving circuit is connected to the driving output terminal of the control circuit, the magnetic field tracking signal output terminal of the magnetic field tracking circuit is connected to the magnetic field tracking signal input terminal of the control circuit; the second comparison input terminal of the magnetic field tracking circuit is connected to the positive pole of the battery. The above-mentioned driving control circuit based on magnetic field intensity tracking, through electromagnetic conversion and the output of the oscillation wave by the driving circuit, the magnetic field tracking circuit tracks the oscillation wave in the magnetic field and outputs the magnetic field tracking signal, and the control circuit controls the driving control signal to output periodically according to the magnetic field tracking signal; the switching loss of the MOS tube in the driving circuit is reduced, thereby greatly reducing the heat generated by the MOS tube.

[0045] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A drive control circuit based on magnetic field intensity tracking, characterized in that: The driving control circuit includes a driving circuit, a magnetic field tracking circuit and a control circuit; The driving output terminal of the driving circuit is connected to the first comparison input terminal of the magnetic field tracking circuit, the driving input terminal of the driving circuit is connected to the driving output terminal of the control circuit, the magnetic field tracking signal output terminal of the magnetic field tracking circuit is connected to the magnetic field tracking signal input terminal of the control circuit; the second comparison input terminal of the magnetic field tracking circuit is connected to the positive electrode of the battery; The driving circuit is used to perform electromagnetic conversion according to the driving control signal inputted from the driving input terminal and output the oscillation wave from the driving output terminal; the magnetic field tracking circuit performs magnetic field tracking on the oscillation wave to output the magnetic field tracking signal through the magnetic field tracking signal output terminal; The control circuit periodically outputs a control driving control signal according to the magnetic field tracking signal.

2. The driving control circuit based on magnetic field intensity tracking according to claim 1, characterized in that: The driving circuit includes a first resistor, a first MOS tube, a first capacitor and a first inductor; One end of the first resistor serves as a driving input end of the driving circuit, the other end of the first resistor is connected to the gate of the first MOS tube, and the source of the first MOS tube is grounded; the drain of the first MOS tube is connected to one end of the first capacitor and one end of the first inductor, and the connection point serves as a driving output end of the driving circuit; the other end of the first capacitor and the other end of the first inductor are both connected to the positive electrode of the battery.

3. The driving control circuit based on magnetic field intensity tracking according to claim 2, characterized in that: The driving circuit further includes a second resistor, which is arranged in parallel between the gate of the first MOS tube and the ground terminal.

4. The driving control circuit based on magnetic field intensity tracking according to any one of claims 1 to 3, characterized in that: The magnetic field tracking circuit includes a voltage reference circuit, a magnetic field strength identification circuit, a comparator, a power supply filter circuit and a filter output circuit; One end of the voltage reference circuit serves as the second comparison input end of the magnetic field tracking circuit, and the other end of the voltage reference circuit is connected to the second input end of the comparator; one end of the magnetic field strength identification circuit serves as the second comparison input end of the magnetic field tracking circuit, and the other end of the magnetic field strength identification circuit is connected to the first input end of the comparator; One end of the power supply filter circuit is grounded, and the other end is connected to the voltage-stabilized power supply and the power input of the comparator at the same time; the ground end of the comparator is grounded; the output end of the comparator is connected to the input end of the filter output circuit, and the output end of the filter output circuit serves as the magnetic field tracking signal output end of the magnetic field tracking circuit.

5. The driving control circuit based on magnetic field intensity tracking according to claim 4, characterized in that: The voltage reference circuit includes a sixth resistor, a tenth resistor and a twelfth capacitor; One end of the sixth resistor is connected to the positive electrode of the battery, and the other end of the sixth resistor is connected to one end of the tenth resistor, one end of the twelfth capacitor and the second input end of the comparator; the other end of the tenth resistor and the other end of the twelfth capacitor are grounded.

6. The driving control circuit based on magnetic field intensity tracking according to claim 4, characterized in that: The magnetic field strength identification circuit includes a seventh resistor, an eleventh resistor and a tenth capacitor; One end of the seventh resistor is connected to the driving output end of the driving circuit; the other end of the seventh resistor is connected to the first input end of the comparator, one end of the eleventh resistor and one end of the tenth capacitor; the other end of the eleventh resistor and the other end of the tenth capacitor are grounded.

7. The driving control circuit based on magnetic field intensity tracking according to claim 4, characterized in that: The filter output circuit includes a ninth resistor and an eleventh capacitor; One end of the ninth resistor is connected to the output end of the comparator; the other end of the ninth resistor is connected to one end of the eleventh capacitor, and the connection point is connected to the magnetic field tracking signal input end of the control circuit; the other end of the eleventh capacitor is grounded.

8. The driving control circuit based on magnetic field intensity tracking according to claim 4, characterized in that: The power supply filter circuit includes a sixth capacitor; One end of the sixth capacitor is grounded, and the other end is connected to the regulated power supply and the power input end of the comparator.

9. The driving control circuit based on magnetic field intensity tracking according to claim 4, characterized in that: The magnetic field tracking circuit also includes an eighth capacitor; the eighth capacitor is arranged in parallel between the first input terminal and the second input terminal of the comparator.

10. A driving control method based on magnetic field intensity tracking, characterized in that: The drive control method is applied to the drive control circuit based on magnetic field intensity tracking according to any one of claims 1 to 9, and the drive control method includes: If the control circuit receives a drive control instruction, the control circuit outputs a drive control signal to the drive circuit through a drive output terminal; the drive control signal is a rectangular square wave; The driving circuit performs electromagnetic conversion according to the received driving control signal and outputs an oscillation wave from the driving output end; the starting time point of the oscillation wave is the starting time point of the low level in the rectangular square wave, and the signal strength of the oscillation wave is positively correlated with the magnetic field strength; The magnetic field tracking circuit receives the oscillation wave and performs magnetic field tracking to output a magnetic field tracking signal through a magnetic field tracking signal output terminal; The control circuit determines whether the received magnetic field tracking signal is at a low level; when the magnetic field is weakest, the magnetic field tracking signal is at a low level; If the control circuit determines that the magnetic field tracking signal is at a low level, the process returns to the step of outputting the driving control signal to the driving circuit through the driving output terminal.

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