CN217216372U

CN217216372U - Power supply boosting driving and surge suppression circuit based on self-oscillation

Info

Publication number: CN217216372U
Application number: CN202221066691.1U
Authority: CN
Inventors: 邱序涛
Original assignee: Chengdu Fujin Power Semiconductor Technology Development Co ltd
Current assignee: Chengdu Fujin Power Semiconductor Technology Development Co ltd
Priority date: 2022-05-06
Filing date: 2022-05-06
Publication date: 2022-08-16
Anticipated expiration: 2032-05-06

Abstract

The utility model discloses a power boost driving and surge suppression circuit based on self-oscillation, belonging to the technical field of power control, comprising a self-oscillation module, a totem pole module and a boost circuit module which are connected in sequence; a switch tube Q1 is arranged between the voltage input end and the voltage output end, the voltage input end is electrically connected between the totem-pole module and the booster circuit module, and the output end of the booster circuit module is connected to the switch tube Q1. The utility model drives the totem pole through the self-oscillation module so as to lead the booster circuit module to carry out boosting treatment, thus realizing the purpose of boosting the driving voltage; meanwhile, through the surge suppression module, the input voltage is surged, the stable output voltage is limited, and the purpose of protecting a post-stage circuit is achieved; the whole circuit does not need to adopt a special chip, so that peripheral components are reduced, the output voltage is controllable, and the cost is reduced.

Description

Power supply boosting driving and surge suppression circuit based on self-oscillation

Technical Field

The utility model relates to a power control technology field especially relates to power boost drive and surge suppression circuit based on self-oscillation.

Background

In some circuit application scenarios, the power output needs to be controlled, for example, the output voltage gradually increases and is in a steady state, and finally the output voltage is approximately equal to the input voltage. There are three common control modes, including controlling the power supply positive and the power supply negative simultaneously, controlling the power supply negative separately, and controlling the power supply positive separately. Taking the way of controlling the power supply only positively as an example, which needs to process the driving of the switching tube, the most common way at present is to add an independent power supply as the driving power supply of the switching tube, and if the switching tube adopts a MOS tube, the reference ground of the power supply is the source electrode. However, the use of a general isolation power supply as a driving power supply for the switching tube causes problems of increased size and cost; if a small-sized isolation power supply is used as a driving power supply of the switching tube, the cost is greatly increased. Further, in the power supply circuit, when a surge occurs in the input voltage, the subsequent devices are easily damaged. In summary, how to achieve stable voltage output without increasing cost and circuit size is a technical problem that needs to be solved urgently.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome the problem among the prior art, provide a power boost drive and surge suppression circuit based on self-excited oscillation.

The purpose of the utility model is realized through the following technical scheme: a switching tube for controlling the output voltage of a power supply is arranged between a voltage input end (power supply input end) and a voltage output end (power supply output end) of the boosting driving circuit to independently control the power supply, namely, the switching tube such as an MOS tube is inserted between the positive pole of an input voltage Vin and the positive pole of an output voltage VO, the drain electrode of the MOS tube is connected with the voltage input end, the source electrode of the MOS tube is connected with the voltage output end, the grid electrode of the MOS tube is used as a control end, and the negative pole of the input voltage Vin and the negative pole of the output voltage VO are both grounded through a capacitor. The boost driving circuit comprises a self-oscillation module, a totem pole module and a boost circuit module which are connected in sequence, the three circuit modules are matched to output a first driving voltage which is stable and is subjected to boost processing, and then drive the switch tube, namely the output end of the boost circuit module is connected with the grid electrode of the MOS tube. The first driving voltage is not a fixed value, and is specifically changed according to the design of a boosting circuit of the boosting circuit module and the boosting multiple, for example, the boosting circuit module comprises a multi-stage boosting sub-circuit, and after multi-stage boosting, the first driving voltage is increased step by step, so that the switching tube is driven to obtain the stable output voltage increased step by step, and the control of the output voltage is realized.

Further, a surge suppression module is arranged between the grid of the switching tube Q1 and the voltage output end; the surge suppression module comprises a voltage comparison sub-circuit and a switch sub-circuit which are connected in sequence, wherein the input end of the voltage comparison sub-circuit is connected with the voltage output end; the switch sub-circuit is connected with the grid electrode of the switch tube Q1 and the voltage output end and is used for jointly regulating the output voltage (the output voltage of the final stage of the voltage output end) by combining with the booster circuit module. When the input voltage is normal, the voltage comparison sub-circuit outputs a low level, the switch sub-circuit does not work at the moment, and the output voltage is controlled by the booster circuit module; when the input voltage surges, the voltage comparison sub-circuit outputs low level, the switch in the switch sub-circuit is switched on, and the output voltage is regulated by the booster circuit module and the switch sub-circuit together, so that the working state of the MOS transistor Q1 is changed, the output voltage is limited, the stable output voltage is obtained, and the purpose of protecting a rear-stage circuit is achieved.

More specifically, the self-oscillation module is configured to generate a level signal with a variable level, preferably a level signal with a periodic variable level, such as a square wave signal with a fixed frequency, and further control the switching state of the totem pole. The totem pole is the existing totem pole drive circuit, and the totem pole drive circuit correspondingly presents an on-off state according to the level signal of the self-excited oscillation module, thereby achieving the purpose of controlling the booster circuit module to carry out boosting treatment. An input voltage is introduced between the input end of the voltage boosting circuit module and the totem-pole module, namely, the voltage input end is electrically connected between the totem-pole module and the voltage boosting circuit module, so that a basic voltage for boosting processing is introduced, and the boosting processing is realized on the basis to obtain a first driving voltage.

The utility model discloses a self-excited oscillation module drive totem pole and then make the boost circuit module carry out the boost processing, and then driving voltage steps up, and whole circuit need not to adopt special chip, need not to increase auxiliary power supply and can realize the switch of switch tube, has reduced peripheral components and parts to this cost spending is reduced when realizing that output voltage is controllable, and the circuit is small, and the flexibility is stronger; and general special chip only can be used for the low pressure occasion simultaneously, and the utility model discloses the circuit adopts basic electronic components, can be used to the high pressure occasion, has improved the generating line power scope, and output voltage is adjustable. Further, the utility model discloses compare with isolation power supply technique, reduced the design of keeping apart the power, reduced the degree of difficulty of design, the development cycle has been shortened in convenient design, has improved product reliability, has reduced the circuit volume, has improved power density.

Furthermore, the self-oscillation boosting driving circuit does not need to adopt a transformer, so that the design of the transformer is reduced, the design difficulty is reduced, the design is convenient, the development period is shortened, and the reliability of the product is improved.

In one example, the self-oscillation module constitutes an oscillation circuit based on an operational amplifier. Specifically, the self-oscillation module comprises an operational amplifier, wherein the equidirectional input end of the operational amplifier is connected with a resistor R2, one end of the resistor R2 is connected with a power supply VCC, and the other end of the resistor R2 is grounded through a resistor R7; the equidirectional input end of the operational amplifier is also sequentially connected with a resistor R4 and a resistor R1, the other end of the resistor R1 is connected to the output end of the operational amplifier, and the output end of the operational amplifier is connected to the totem-pole module through a resistor R6; meanwhile, the reverse input end of the operational amplifier is connected with a resistor R3, one end of a resistor R3 is connected between the resistor R4 and the resistor R1, and the other end of the resistor R3 is connected with a grounding capacitor C7. Under the condition of not adding external oscillation, the self-oscillation module can generate a signal with fixed frequency, when the signal output is high, the voltage is the power supply voltage VCC, and when the signal output is low, the voltage is the grounding voltage.

In one example, the totem pole module includes an NPN transistor Q2 and a PNP transistor Q3, an emitter of the transistor Q2 is connected to an emitter of the transistor Q3, a base of the transistor Q2 is connected to a base of the transistor Q3, a collector of the transistor Q2 is connected to a high level, a collector of the transistor Q3 is grounded, and an output of the self-oscillation module is connected between the base of the transistor Q2 and a base of the transistor Q3, on the basis of which the transistor Q2 and the transistor Q3 are alternately turned on when the self-oscillation module alternately outputs high and low levels.

In one example, the output end of the booster circuit module is connected with a current-limiting protection circuit. Specifically, the current-limiting protection circuit comprises a PNP type triode Q4, a resistor R8 is connected to an emitter of the triode Q4, the other end of the resistor R8 is connected with a diode D3, and a zener diode D7 is connected in parallel to the resistor R8; the base electrode of the triode Q4 is connected with a resistor R9, and the other end of the resistor R9 is connected between the cathode of the diode D3 and the grounding capacitor C6; the base electrode of the triode Q4 is also connected with a grounding resistor R10 with a protection function, a grounding capacitor C8 is connected between the collector electrode and the base electrode of the triode Q4, the other end of the capacitor C8 is sequentially connected with a diode D2 and a zener diode D6, and the grid electrode of the switching tube Q1 is connected between the cathode of the diode D2 and the cathode of the zener diode D6. At this time, the voltage (first driving voltage) across the capacitor C8 is used to drive the switching tube, thereby realizing the control of the output voltage VO. When the resistor R9 and the resistor R10 control the conduction of the triode Q4, if the conduction current of the triode Q4 is overlarge, the voltage drop on the resistor R8 is increased, and when the base level voltage of the triode Q4 is close to the voltage of an emitter level, the triode Q4 works in an amplification state to limit the current output; when the voltage boosting circuit normally works, the triode Q4 is conducted, the voltage on the capacitor C6 supplies power to the capacitor C8 through the resistor R8 and the triode Q4, the voltage of the capacitor C8 is Vin-VD1-VQ3+ VCC-VQ2-VD3-VQ4 (corresponding to a first driving voltage), the MOS transistor Q1 is driven based on the voltage, if the VCC voltage is high enough, the voltage can enable the Q1 to be completely conducted, the output voltage VO is close to Vin, the purpose of controlling output is achieved, if the VCC voltage is too low, the boosting times are increased, the voltage on the capacitor C8 is increased, and the Q1 can be completely conducted.

In one example, the boost circuit module comprises a plurality of boost sub-circuits, and the boost is realized by adjusting the boost multiple of the boost sub-circuits and device parameters (such as resistance parameters, capacitance parameters and the like) in the boost sub-circuits, so that the flexibility of boost is improved. The utility model discloses boost sub-circuit forms based on basic electronic components design, specifically forms based on the design of electric capacity charge-discharge characteristic, under the condition of self-excited oscillation module output high-low level control totem pole on-off state, electric capacity carries out the charge-discharge and then obtains stable first driving voltage in the boost sub-circuit.

In one example, the voltage comparison sub-circuit is specifically configured based on the operational amplifier N2A, and the switch sub-circuit includes an NPN transistor Q6 and a PNP transistor Q5. Specifically, the equidirectional input end of the operational amplifier N2A is sequentially connected with a resistor R14 and a resistor R13, one end of the resistor R13 is connected to the voltage output end, and the other end is grounded through a resistor R17; the inverting input end of the operational amplifier N2A is inputted with a reference voltage Vref, and the reference voltage Vref is set according to the input voltage when the current circuit normally works. The output end of the operational amplifier N2A is sequentially connected with a resistor R15 and a triode Q6, the emitter of the triode Q6 is connected with a resistor R16, and the other end of the resistor R16 is connected between the base of the triode Q6 and the output end of the operational amplifier N2A; a collector of the triode Q6 is connected with a resistor R12, the other end of the resistor R12 is connected to a base electrode of the triode Q5, a collector of the triode Q5 is connected between a source electrode and a voltage output end of the MOS tube, and an emitter of the triode Q5 is connected to a grid electrode of the MOS tube; the base electrode of the triode Q5 is connected with a resistor R11, and the other end of the resistor R11 is connected between the source electrode of the MOS tube and the collector electrode of the triode Q5 through a voltage stabilizing diode D6; the diode D2 is connected to the voltage stabilizing diode D6, and the other end of the diode D2 is connected to the output end of the booster circuit module.

In one example, the boost circuit module comprises a first boost sub-circuit for performing a one-stage boost process on the circuit voltage. Specifically, the first boost sub-circuit comprises a diode D1, a resistor R5, a diode D3 and a grounded capacitor C6 which are connected in sequence, and further comprises a capacitor C4 arranged between the resistor R5 and the totem-pole module.

Combining the above examples, a preferred example is obtained, where the working principle of the whole circuit is as follows:

when the power-on is started, when the oscillator (self-oscillation module) is not in operation, the voltage of the capacitor C8 is Vin-VD1-VD3-VQ 4;

when the oscillator starts to work, if the output of the oscillator in the first period is low, the triode Q2 is turned off, the triode Q3 is turned on, the input voltage Vin charges the capacitor C4 through the diode D1, the resistor R5 and the triode Q3, so that the voltage on the capacitor C4 reaches Vin-VD1-VQ3, the Vin charges the capacitor C6 and the capacitor C8 through the diode D1, the resistor R5, the diode D3, the resistor R8 and the triode Q4, and the voltage of the capacitor C6 is Vin-VD1 VD3 and the voltage of the capacitor C8 is Vin-VD1-VD3-VQ 4;

when the output of the oscillator is high, the triode Q2 is switched on, the triode Q3 is switched off, the voltage on the capacitor C4 is Vin-VD1-VQ3, the voltage on the capacitor C6 is Vin-VD1-VQ3+ VCC-VQ2-VD3, and the voltage on the capacitor C8 is Vin-VD1-VQ3+ VCC-VQ2-VD3-VQ 4;

when the output of the oscillator changes from high to low, the triode Q3 is turned on, the diode D3 is turned off, the input voltage Vin charges the capacitor C4 through the diode D1, the resistor R5 and the triode Q3, so that the voltage on the capacitor C4 reaches Vin-VD1-VQ3, the voltage on the capacitor C6 is Vin-VD1-VQ3+ VCC-VQ2-VD3, the voltage on the capacitor C8 is Vin-VD 56 1-VQ3+ VCC-VQ2-VD3-VQ4, namely the oscillator maintains the stability of the voltage on the capacitor C8 through continuous output level conversion to achieve the purpose of boosting, in the example, boosting is primary boosting, and secondary boosting, third boosting and more than third boosting can be realized through adding a boosting circuit. Furthermore, when the output voltage is greater than the set voltage (the reference voltage Vref), the resistor R13, the resistor R14, the resistor R15, the resistor R16, the resistor R17 and the operational amplifier N2A control the conduction state of the transistor Q6; the resistor R11, the resistor R12 and the triode Q6 control the working state of the triode Q5, and the voltage on the diode D6 is changed by controlling the working state of the triode Q5, so that the working state of the MOS transistor Q1 is changed, and the purpose of stabilizing the output voltage is achieved.

In one example, the boost circuit module comprises a first boost sub-circuit and a secondary boost sub-circuit, and the first boost sub-circuit cooperates with the secondary boost sub-circuit to perform secondary boost processing on the circuit voltage. Specifically, as described above, the first boost sub-circuit structure includes the diode D4, the grounded capacitor C5, the diode D5, and the capacitor C3, which are connected in sequence, wherein one end of the capacitor C3 is connected between the resistor R5 and the diode D4, and the other end of the capacitor C3 is connected; diode D5 and diode D3. In this example, the voltage of the capacitor C3 is further superimposed from the primary voltage boost to the secondary voltage boost, and the capacitor C3 is continuously charged after the primary voltage boost is completed, thereby implementing the secondary voltage boost.

In one example, the boost circuit module comprises a first boost sub-circuit, a second boost sub-circuit and a third boost sub-circuit, and the first boost sub-circuit and the second boost sub-circuit cooperate with the third boost sub-circuit to perform three-stage boost processing on the circuit voltage. Specifically, the first boost sub-circuit and the second boost sub-circuit are configured as described above, the third boost sub-circuit includes the diode D8, the grounded capacitor C9, the diode D9, and the capacitor C10, one end of the capacitor C10 is connected between the diode D5 and the diode D8, and the other end of the capacitor C10 is connected between the diode D9 and the diode D3. In this example, the voltage of the capacitor C10 is further superimposed from the secondary boost to the tertiary boost, and the capacitor C10 is continuously charged after the secondary boost is completed, thereby realizing the tertiary boost.

It should be further noted that the technical features corresponding to the above examples can be combined with each other or replaced to form a new technical solution.

Compared with the prior art, the utility model discloses beneficial effect is:

the utility model drives the totem pole through the self-oscillation module so as to lead the booster circuit module to carry out boosting treatment, thus realizing the purpose of boosting the driving voltage; meanwhile, through the surge suppression module, the input voltage is surged, the stable output voltage is limited, and the purpose of protecting a post-stage circuit is achieved; the whole circuit does not need to adopt a special chip, so that peripheral components are reduced, the output voltage is controllable, the cost is reduced, and the circuit is small in size; and general special chip only can be used for the low pressure occasion simultaneously, and the utility model discloses the circuit adopts basic electronic components, can be used to the high pressure occasion, has improved the generating line power scope, and output voltage is adjustable.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention.

Fig. 1 is a schematic diagram of a primary boost circuit with surge suppression function according to an example of the present invention;

fig. 2 is a schematic diagram of a secondary boost circuit having a surge suppression function in an example of the present invention.

Detailed Description

The technical solution of the present invention will be described clearly and completely with reference to the accompanying drawings, and obviously, the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like are the directions or positional relationships indicated on the basis of the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element indicated must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Furthermore, the technical features mentioned in the different embodiments of the invention described below can be combined with each other as long as they do not conflict with each other.

Example 1

The present embodiment provides a primary boost driving application with a surge suppression function, and a schematic circuit diagram of the primary boost driving application is shown in fig. 1, where a circuit input voltage Vin is 28V, VCC is 10V, and an output voltage VO is required to be 27.75 ± 0.25V; vin surges input voltage of 50V, and protection limiting voltage of 30V, and the working principle of the circuit is as follows:

the first state: when Vin supplies power and VCC does not supply power, the oscillator does not work, Vin charges a capacitor C6 and a capacitor C8 through a diode D1, a resistor R5, a diode D3, a resistor R8 and a triode Q4, when the voltage of the capacitor C6 reaches 26.6V, the voltage on the capacitor C8 reaches 26.3V, the charging is balanced, the voltage on the capacitor C8 drives a MOS tube Q1, and the output voltage VO is 22.6V.

And a second state: when Vin and VCC are supplied with power at the same time, the oscillator starts to work, if the output of the oscillator is high at the beginning of oscillation, the working state of the circuit is consistent if the state is one, and the output voltage VO is 22.6V.

And a third state: if the oscillator output is low at the beginning of oscillation, the triode Q2 is turned off, the triode Q3 is turned on, Vin charges the capacitor C4 through the diode D1, the resistor R5 and the triode Q3, Vin charges the capacitor C6 and the capacitor C8 through the diode D1, the resistor R5, the diode D3, the resistor R8 and the triode Q4, when the voltage of the capacitor C4 reaches 26.6V, the voltage of the capacitor C6 reaches 26.6V and the voltage of the capacitor C8 reaches 26.3V, the charging is balanced, the voltage of the capacitor C8 drives the MOS tube Q1, and the output voltage VO is 22.6V.

And a fourth state: when the output of the oscillator is changed from low to high, the triode Q2 is switched on, the triode Q3 is switched off, the diode D1 is reversely cut off, VCC charges the capacitor C6 and the capacitor C8 through the triode Q2, the capacitor C4, the diode D3, the resistor R8 and the triode Q4, when the voltage of the capacitor C6 reaches 35.2V and the voltage of the capacitor C8 reaches 34.9V, the charging is balanced, the voltage of the capacitor C8 drives the MOS transistor Q1, and the output voltage VO is 27.9V.

And a fifth state: when the output of the oscillator changes from high to low, the triode Q2 is turned off, the triode Q3 is turned on, Vin charges the capacitor C4 through the diode D1, the resistor R5 and the triode Q3, when the voltage of the capacitor C4 is 26.6V, the charging is balanced, the diode D3 is turned off in the reverse direction, the voltage of the capacitor C6 and the voltage of the capacitor C8 are maintained at the voltage of the last state, the MOS transistor Q1 is driven by the voltage of the capacitor C8, and the output voltage VO is 27.9V.

The oscillator maintains the stability of the voltage on the capacitor C8 through continuous conversion of output level and charging and discharging, and ensures the reliable opening of the switch tube, thereby achieving the purpose of controlling output.

In the boosting regulation process (from the first state to the fifth state), when Vin is normally input, the resistor R13, the resistor R14 and the resistor R17 control the output of the operational amplifier N2A to be low, and the output of the operational amplifier N2A turns off the triode Q6 through the resistor R15 and the resistor R16; the transistor Q6 turns off the transistor Q5 through the resistor R11 and the resistor R12, and the voltage on the C8 controls the output voltage. When Vin surges for input, the resistor R13, the resistor R14 and the resistor R17 control the output of the N2A to be high, and the output of the operational amplifier N2A turns on a triode Q6 through a resistor R15 and a resistor R16; the triode Q6 determines the working state of the triode Q5 through a resistor R11 and a resistor R12, the voltage on the diode D6 is determined by the common adjustment of the voltage on the C8 and the surge suppression module, the working state of the MOS transistor Q1 is changed, the output voltage is stabilized at 30V, and therefore the purpose of protecting a rear-stage circuit is achieved by limiting and stabilizing the output voltage.

Example 2

The present embodiment provides a secondary boost driving application with surge suppression function, and a schematic circuit diagram of the secondary boost driving application is shown in fig. 2, where Vin is 28V, VCC is 5V, and VO is required to be 27.75 ± 0.25V; vin surges input voltage of 50V, and protection limiting voltage of 30V, and the working principle of the circuit is as follows:

the first state: when Vin supplies power and VCC does not supply power, the oscillator does not work, Vin charges a capacitor C5, a capacitor C6 and a capacitor C8 through a diode D1, a resistor R5, a diode D4, a diode D5, a diode D3, a resistor R8 and a triode Q4, when the voltage of the capacitor C5 reaches 26.6V, the voltage of the capacitor C6 reaches 25.2V, the voltage on the capacitor C8 reaches 24.9V, the charging is balanced, the voltage on the capacitor C8 drives an MOS tube Q1, and the output voltage VO is 21.2V.

And a second state: when Vin and VCC are supplied with power at the same time, the oscillator starts to work, if the output of the oscillator is high at the beginning of oscillation, the working state of the circuit is consistent if the state is one, and the output voltage VO is 21.2V.

And a third state: if the oscillator output is low at the beginning of oscillation, the triode Q2 is turned off, the triode Q3 is turned on, Vin charges the capacitor C4 through the diode D1, the resistor R5 and the triode Q3, Vin charges the capacitor C5, the capacitor C6 and the capacitor C8 through the diode D1, the resistor R5, the diode D4, the diode D5, the diode D3, the resistor R8 and the triode Q4, when the voltage of the capacitor C4 reaches 26.6V, the voltage of the capacitor C5 reaches 26.6V, the voltage of the capacitor C6 reaches 25.2V and the voltage of the capacitor C8 reaches 24.9V, the charging is balanced, the voltage of the capacitor C8 drives the MOS tube Q1, and the output voltage VO is 21.2V.

And a fourth state: when the output of the oscillator is changed from low to high, the triode Q2 is switched on, the triode Q3 is switched off, the diode D1 is reversely cut off, VCC charges the capacitor C5, the capacitor C6 and the capacitor C8 through the triode Q2, the capacitor C4, the diode D4, the diode D5, the diode D3, the resistor R8 and the triode Q4, when the voltage of the capacitor C5 reaches 30.2V, the voltage of the capacitor C6 reaches 28.8V and the voltage of the capacitor C8 reaches 28.5V, the charging is balanced, the voltage on the capacitor C8 drives the MOS transistor Q1, and the output voltage VO is 24.8V.

And a fifth state: when the output of the oscillator changes from high to low, the triode Q2 is turned off, the triode Q3 is turned on, Vin charges the capacitor C4 through the diode D1, the resistor R5 and the triode Q3, when the voltage of the capacitor C4 is 26.6V, the charging is balanced, the diode D4 and the diode D3 are turned off in the reverse direction, the voltage of the capacitor C5, the voltage of the capacitor C6 and the voltage of the capacitor C8 are maintained at the voltage of the last state, the voltage of the capacitor C5 charges the capacitor C3 through the diode D5, the capacitor C4 and the triode Q3, when the voltage of the capacitor C3 reaches 2.2V, the charging is balanced, the voltage of the capacitor C8 is used for driving the MOS tube Q1, and the output voltage VO is 24.8V.

And a sixth state: when the output of the oscillator changes from low to high, the triode Q2 is switched on, the triode Q3 is switched off, the diode D1 is switched off in the reverse direction, VCC charges the capacitor C5 through the triode Q2, the capacitor C4 and the diode D4, VCC charges the capacitor C6 and the capacitor C8 through the triode Q2, the capacitor C4, the capacitor C3, the diode D3, the resistor R8 and the triode Q4, the diode D5 is switched off in the reverse direction, when the voltage of the capacitor C5 reaches 30.2V, the voltage of the capacitor C6 reaches 32.4V, the voltage of the capacitor C8 reaches 32.1V, the charging is balanced, the voltage of the capacitor C8 drives the MOS transistor Q1, and the output voltage VO is 27.9V.

And a seventh state: when the output of the oscillator changes from high to low, the triode Q2 is turned off, the triode Q3 is turned on, Vin charges the capacitor C4 through the diode D1, the resistor R5 and the triode Q3, when the voltage of the capacitor C4 is 26.6V, the charging is balanced, the diode D4 and the diode D3 are turned off in the reverse direction, the voltage of the capacitor C5, the voltage of the capacitor C6 and the voltage of the capacitor C8 are maintained at the voltage of the last state, the voltage of the capacitor C5 charges the capacitor C3 through the diode D5, the capacitor C4 and the triode Q3, when the voltage of the capacitor C3 reaches 2.2V, the charging is balanced, the voltage of the capacitor C8 is used for driving the MOS tube Q1, and the output voltage VO is 27.9V.

In the boosting regulation process (from the first state to the seventh state), when Vin is normally input, the resistor R13, the resistor R14 and the resistor R17 control the output of the operational amplifier N2A to be low, and the output of the operational amplifier N2A turns off the triode Q6 through the resistor R15 and the resistor R16; the transistor Q6 turns off the transistor Q5 through the resistor R11 and the resistor R12, and the voltage on the transistor C8 controls the output voltage. When Vin is input in surge, the resistor R13, the resistor R14 and the resistor R17 control the output of the operational amplifier N2A to be high, and the output of the operational amplifier N2A turns on a triode Q6 through a resistor R15 and a resistor R16; the triode Q6 determines the working state of the triode Q5 through a resistor R11 and a resistor R12, the voltage on the diode D6 is determined by the common adjustment of the voltage on the C8 and the surge suppression module, the working state of the MOS transistor Q1 is changed, the output voltage is stabilized at 30V, and therefore the purpose of protecting a rear-stage circuit is achieved by limiting and stabilizing the output voltage.

The above detailed description is for the present invention, and it should not be understood that the detailed description of the present invention is limited to these descriptions, and it is obvious to those skilled in the art that the present invention can be implemented by a plurality of simple deductions and replacements without departing from the spirit of the present invention, and all should be considered as belonging to the protection scope of the present invention.

Claims

1. Power boost drive and surge suppression circuit based on self-oscillation, its characterized in that: the circuit comprises a self-excited oscillation module, a totem pole module and a booster circuit module which are connected in sequence; a switch tube Q1 is arranged between the voltage input end and the voltage output end, the voltage input end is connected between the totem-pole module and the booster circuit module, and the output end of the booster circuit module is connected to a switch tube Q1; a surge suppression module is arranged between the grid of the switching tube Q1 and the voltage output end;

the surge suppression module comprises a voltage comparison sub-circuit and a switch sub-circuit which are connected in sequence, and the input end of the voltage comparison sub-circuit is connected with the voltage output end; the switch sub-circuit is connected with the grid electrode and the voltage output end of the switch tube Q1 and is used for combining the booster circuit module to regulate the output voltage.

2. A self-oscillation based power supply boost driving and surge suppression circuit according to claim 1, wherein: the self-oscillation module forms an oscillation circuit based on the operational amplifier.

3. A self-oscillation based power supply boost driving and surge suppression circuit according to claim 1, wherein: the totem pole module comprises an NPN type triode Q2 and a PNP type triode Q3, wherein an emitting electrode of the triode Q2 is connected with an emitting electrode of the triode Q3, a base electrode of the triode Q2 is connected with a base electrode of the triode Q3, a collector electrode of the triode Q2 is connected with a high level, and a collector electrode of the triode Q3 is grounded.

4. The self-oscillation based power supply boost driving and surge suppression circuit according to claim 1, wherein: and the output end of the booster circuit module is connected with a current-limiting protection circuit.

5. A self-oscillation based power supply boost driving and surge suppression circuit according to claim 1, wherein: the boosting circuit module comprises a first boosting sub-circuit used for carrying out primary boosting processing on circuit voltage.

6. A self-oscillation based power supply boost driving and surge suppression circuit according to claim 5, wherein: the first boosting sub-circuit comprises a diode D1, a resistor R5, a diode D3 and a grounded capacitor C6 which are connected in sequence, and further comprises a capacitor C4 arranged between the resistor R5 and the totem-pole module.

7. A self-oscillation based power supply boost driving and surge suppression circuit according to claim 1, wherein: the boost circuit module comprises a first boost sub-circuit and a secondary boost sub-circuit, and the first boost sub-circuit is matched with the secondary boost sub-circuit to carry out secondary boost processing on the circuit voltage.

8. A self-oscillation based power supply boost driving and surge suppression circuit according to claim 7, wherein: the first boosting sub-circuit comprises a diode D1, a resistor R5, a diode D3 and a grounded capacitor C6 which are connected in sequence, and further comprises a capacitor C4 arranged between the resistor R5 and the totem-pole module;

the secondary boosting sub-circuit comprises a diode D4, a grounded capacitor C5, a diode D5 and a capacitor C3 which are sequentially connected, one end of the capacitor C3 is connected between a resistor R5 and a diode D4, and the other end of the capacitor C3 is connected between a diode D5 and a diode D3.

9. A self-oscillation based power supply boost driving and surge suppression circuit according to claim 1, wherein: the boost circuit module comprises a first boost sub-circuit, a secondary boost sub-circuit and a tertiary boost sub-circuit, wherein the first boost sub-circuit and the secondary boost sub-circuit are matched with the tertiary boost sub-circuit to carry out three-stage boost processing on circuit voltage.

10. A self-oscillation based power supply boost driving and surge suppression circuit according to claim 9, wherein: the first boosting sub-circuit comprises a diode D1, a resistor R5, a diode D3 and a grounded capacitor C6 which are connected in sequence, and further comprises a capacitor C4 arranged between the resistor R5 and the totem-pole module;

the secondary booster sub-circuit comprises a diode D4, a grounded capacitor C5, a diode D5 and a capacitor C3 which are sequentially connected, one end of the capacitor C3 is connected between a resistor R5 and a diode D4, and the other end of the capacitor C3 is connected between a diode D5 and a diode D3;

the tertiary boost sub-circuit comprises a diode D8, a grounded capacitor C9, a diode D9 and a capacitor C10 which are sequentially connected, wherein one end of the capacitor C10 is connected between the diode D5 and the diode D8, and the other end of the capacitor C10 is connected between the diode D9 and the diode D3.