CN104518650A

CN104518650A - Driving circuit for driving switching devices, control circuit and device

Info

Publication number: CN104518650A
Application number: CN201410788791.9A
Authority: CN
Inventors: 杨向东; 陈庆彬; 杨和钱
Original assignee: Hangzhou Huawei Digital Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2014-12-18
Filing date: 2014-12-18
Publication date: 2015-04-15
Anticipated expiration: 2034-12-18
Also published as: CN104518650B

Abstract

An embodiment of the invention provides a driving circuit for driving switching devices, a control circuit and a device. The driving circuit comprises a first branch used for driving a first main switching device, a second branch used for driving a second main switching device, a first auxiliary switching device and a second auxiliary switching device, wherein the first branch comprises a primary side of a transformer, the second branch comprises a secondary side of the transformer, and the first auxiliary switching device and the second auxiliary switching device are used for controlling voltage difference between the first end and the second end of the first branch. By the driving circuit, the control circuit and the device, isolation drive of the main switching devices can be realized, and the application range of the lossless drive technology can be effectively enlarged.

Description

For the drive circuit of driving switch device, control circuit and device

Technical field

The embodiment of the present invention relates to circuit field, and more specifically, relates to a kind of drive circuit for driving switch device, control circuit and device.

Background technology

Switching Power Supply (Switching Mode Power Supply) is that one utilizes modern power electronics technology, control switch device open and disconnect time ratio, maintain the power supply of regulated output voltage, can be described as again exchange type power or switch converters, is a kind of high frequency device for converting electric energy.Wherein, switching device is generally metal-oxide layer semiconductcor field effect transistor (Metal-Oxide-Semiconductor Field-EffectTransistor, referred to as " MOSFET "), can referred to as metal-oxide-semiconductor.

The driving loss P=1/2*Cgs*U*fs of metal-oxide-semiconductor, wherein Cgs is metal-oxide-semiconductor grid source capacitance, and U is the driving voltage of metal-oxide-semiconductor, and fs is the frequency opened with disconnect of metal-oxide-semiconductor.Along with Switching Power Supply is to more high frequency development, the fs of metal-oxide-semiconductor improves constantly, and the driving loss P of metal-oxide-semiconductor also can significantly increase.In current technology by utilizing inductance, storage that capacity cell realizes energy and release, realize the harmless driving of metal-oxide-semiconductor.

There are some drawbacks in existing harmless Driving technique, such as, can only drive the metal-oxide-semiconductor of common source, therefore cannot realize the driving to the metal-oxide-semiconductor of two on same brachium pontis, limit the range of application of harmless Driving technique.

Summary of the invention

The embodiment of the present invention provides a kind of drive circuit for driving switch device, control circuit and device, can realize the isolation drive of switching device, effectively can expand the range of application of harmless Driving technique.

First aspect provides a kind of drive circuit for driving switch device, and this drive circuit comprises:

For driving the first branch road of the first main switching device, this first branch road comprises the first former limit of the first storage capacitor and the first transformer be connected in series, the first end of this first branch road connects the first end of this first main switching device, second end of this first branch road connects the second end of this first main switching device, second end of this first branch road also connects the negative pole of power supply, this first main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of this first branch road of this first branch road is more than or equal to the first voltage threshold, second end of this first main switching device and the 3rd end conducting of this first main switching device, the instruction of this first voltage threshold is provided for the voltage of conducting between the second end of this first main switching device and the 3rd end of this first main switching device, and this first voltage threshold is greater than zero,

First auxiliary switch device, the first end of this first auxiliary switch device connects the first end of this first branch road, second end of this first auxiliary switch device connects the positive pole of this power supply, this the first auxiliary switch device comprises the first switch in parallel and the first parasitic capacitance, wherein, when this first switch is closed, the first end of this first branch road is connected with the positive pole of this power supply by this closed first switch, when this first switch disconnects, the first end of this first branch road is connected with the positive pole of this power supply by this first parasitic capacitance;

Second auxiliary switch device, the first end of this second auxiliary switch device connects the first end of this first branch road, second end of this second auxiliary switch device connects the negative pole of this power supply, this the second auxiliary switch device comprises second switch in parallel and the second parasitic capacitance, wherein, when this second switch is closed, the first end of this first branch road is connected with the negative pole of this power supply by this closed second switch, when this second switch disconnects, the first end of this first branch road is connected with the negative pole of this power supply by this second parasitic capacitance;

For driving the second branch road of the second main switching device, this second branch road comprises the first secondary of the second storage capacitor and this first transformer be connected in series, the first end of this second branch road connects the first end of this second main switching device, second end of this second branch road connects the second end of this second main switching device, wherein, this second main switching device also comprises the 3rd end, when voltage difference between the first end and the second end of this second branch road of this second branch road is more than or equal to the second voltage threshold, second end of this second main switching device and the 3rd end conducting of this second main switching device, the instruction of this second voltage threshold is provided for the voltage of conducting between the second end of this second main switching device and the 3rd end of this second main switching device, and this second voltage threshold is greater than zero.

In conjunction with first aspect, in the first possible implementation of first aspect, this drive circuit also comprises:

Act on the first control signal input of this first auxiliary switch device, the first control signal of this first control signal input input is used for, and controls the closed of this first switch and disconnects;

Act on the second control signal input of this second auxiliary switch device, the second control signal of this second control signal input input is used for, and controls the closed of this second switch and disconnects.

In conjunction with the first possible implementation of first aspect, in the implementation that the second of first aspect is possible,

From the first moment, until the second moment, this first control signal specifically for, control this first switch close, and this second control signal specifically for, control this second switch disconnect;

From this second moment, until the 3rd moment, this first control signal specifically for, control this first switch disconnect, and this second control signal specifically for, control this second switch disconnect;

From the 3rd moment, until the 4th moment, this first control signal specifically for, control this first switch disconnect, and this second control signal specifically for, control this second switch close;

From the 4th moment, until the 5th moment, this first control signal specifically for, control this first switch disconnect, and this second control signal specifically for, control this second switch disconnect,

Wherein, each moment above-mentioned is different.

In conjunction with the implementation that the first or the second of first aspect or first aspect are possible, in the third possible implementation of first aspect, this first main switching device, this second main switching device, this first auxiliary switch device and this second auxiliary switch device are MOS type field effect transistor MOSFET.

In conjunction with first aspect, in the 4th kind of possible implementation of first aspect, this drive circuit also comprises:

For driving the 3rd branch road of the 3rd main switching device, 3rd branch road comprises the second former limit of the 3rd storage capacitor and the second transformer be connected in series, the first end of the 3rd branch road connects the first end of the 3rd main switching device, second end of the 3rd branch road connects the second end of the 3rd main switching device, second end of the 3rd branch road also connects the negative pole of this power supply, 3rd main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of the 3rd branch road of the 3rd branch road is more than or equal to tertiary voltage threshold value, second end of the 3rd main switching device and the 3rd end conducting of the 3rd main switching device, the instruction of this tertiary voltage threshold value is provided for the voltage of conducting between the second end of the 3rd main switching device and the 3rd end of the 3rd main switching device, and this tertiary voltage threshold value is greater than zero,

3rd auxiliary switch device, the first end of the 3rd auxiliary switch device connects the first end of the 3rd branch road, second end of the 3rd auxiliary switch device connects the positive pole of this power supply, 3rd auxiliary switch device comprises the 3rd switch and trixenie electric capacity in parallel, wherein, when the 3rd switch is closed, the first end of the 3rd branch road is connected with the positive pole of this power supply by the 3rd closed switch, when the 3rd switch disconnects, the first end of the 3rd branch road is connected with the positive pole of this power supply by this trixenie electric capacity;

4th auxiliary switch device, the first end of the 4th auxiliary switch device connects the first end of the 3rd branch road, second end of the 4th auxiliary switch device connects the negative pole of this power supply, 4th auxiliary switch device comprises the 4th switch in parallel and the 4th parasitic capacitance, wherein, when the 4th switch is closed, the first end of the 3rd branch road is connected with the negative pole of this power supply by the 4th closed switch, when the 4th switch disconnects, the first end of the 3rd branch road is connected with the negative pole of this power supply by the 4th parasitic capacitance;

For driving the 4th branch road of the 4th main switching device, 4th branch road comprises the second secondary of the 4th storage capacitor and this second transformer be connected in series, the first end of the 4th branch road connects the first end of the 4th main switching device, second end of the 4th branch road connects the second end of the 4th main switching device, wherein, 4th main switching device also comprises the 3rd end, when voltage difference between the first end and the second end of the 4th branch road of the 4th branch road is more than or equal to the 4th voltage threshold, second end of the 4th main switching device and the 3rd end conducting of the 4th main switching device, 4th voltage threshold instruction is provided for the voltage of conducting between the second end of the 4th main switching device and the 3rd end of the 4th main switching device, and the 4th voltage threshold is greater than zero.

In conjunction with the 4th kind of possible implementation of first aspect, in the 5th kind of possible implementation of first aspect, the 3rd switch does not close with this first switch simultaneously.

In conjunction with the 4th kind or the 5th kind of possible implementation of first aspect, in the 6th kind of possible implementation of first aspect, this drive circuit also comprises:

Act on the second control signal input of this second auxiliary switch device, the second control signal of this second control signal input input is used for, and controls the closed of this second switch and disconnects;

Act on the 3rd control signal input of the 3rd auxiliary switch device, the 3rd control signal of the 3rd control signal input input is used for, and controls the closed of the 3rd switch and disconnects;

Act on the 4th control signal input of the 4th auxiliary switch device, the 4th control signal of the 4th control signal input input is used for, and controls the closed of the 4th switch and disconnects.

In conjunction with the 6th kind of possible implementation of first aspect, in the 7th kind of possible implementation of first aspect,

From the first moment, until the second moment, this first control signal is used for, control this first switch to close, and this second control signal is used for, controls this second switch and disconnect, and the 3rd control signal is used for, control the 3rd switch to disconnect, and the 4th control signal is used for, controls the 4th switch and close;

From this second moment, until the 3rd moment, this first control signal is used for, control this first switch to disconnect, and this second control signal is used for, controls this second switch and disconnect, and the 3rd control signal is used for, control the 3rd switch to disconnect, and the 4th control signal is used for, controls the 4th switch and close;

From the 3rd moment, until the 4th moment, this first control signal is used for, control this first switch to disconnect, and this second control signal is used for, controls this second switch and close, and the 3rd control signal is used for, control the 3rd switch to disconnect, and the 4th control signal is used for, controls the 4th switch and close;

From the 4th moment, until the 5th moment, this first control signal is used for, control this first switch to disconnect, and this second control signal is used for, controls this second switch and close, and the 3rd control signal is used for, control the 3rd switch to disconnect, and the 4th control signal is used for, controls the 4th switch and disconnect;

From the 5th moment, until the 6th moment, this first control signal is used for, control this first switch to disconnect, and this second control signal is used for, controls this second switch and close, and the 3rd control signal is used for, control the 3rd switch to close, and the 4th control signal is used for, controls the 4th switch and disconnect;

From the 6th moment, until the 7th moment, this first control signal is used for, control this first switch to disconnect, and this second control signal is used for, controls this second switch and close, and the 3rd control signal is used for, control the 3rd switch to disconnect, and the 4th control signal is used for, controls the 4th switch and disconnect;

From the 7th moment, until the 8th moment, this first control signal is used for, control this first switch to disconnect, and this second control signal is used for, controls this second switch and close, and the 3rd control signal is used for, control the 3rd switch to disconnect, and the 4th control signal is used for, controls the 4th switch and close;

From the 8th moment, until the 9th moment, this first control signal is used for, and control this first switch and disconnect, and this second control signal is used for, control this second switch to disconnect, and the 3rd control signal is used for, control the 3rd switch and disconnect, and the 4th control signal is used for, control the 4th switch to close

Wherein, each moment above-mentioned is different.

In conjunction with any one the possible implementation in the 4th kind to the 6th kind possible implementation of first aspect, in the 8th kind of possible implementation of first aspect, this first main switching device, this second main switching device, the 3rd main switching device, the 4th main switching device, this first auxiliary switch device, this second auxiliary switch device, the 3rd auxiliary switch device and the 4th auxiliary switch device are MOS type field effect transistor MOSFET.

In conjunction with any one the possible implementation in the 4th kind to the 8th kind possible implementation of first aspect, in the 9th kind of possible implementation of first aspect, this drive circuit also comprises:

For driving the 5th branch road of the 5th main switching device, 5th branch road comprises the 3rd secondary of the 5th storage capacitor and this first transformer be connected in series, the first end of the 5th branch road connects the first end of the 5th main switching device, second end of the 5th branch road connects the second end of the 5th main switching device, 5th main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of the 5th branch road of the 5th branch road is more than or equal to the 5th voltage threshold, second end of the 5th main switching device and the 3rd end conducting of the 5th main switching device, 5th voltage threshold instruction is provided for the voltage of conducting between the second end of the 5th main switching device and the 3rd end of the 5th main switching device, 5th voltage threshold is greater than zero,

For driving the 6th branch road of the 6th main switching device, 6th branch road comprises the 4th secondary of the 6th storage capacitor and this second transformer be connected in series, the first end of the 6th branch road connects the first end of the 6th main switching device, second end of the 6th branch road connects the second end of the 6th main switching device, 6th main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of the 6th branch road of the 6th branch road is more than or equal to the 6th voltage threshold, second end of the 6th main switching device and the 3rd end conducting of the 6th main switching device, 6th voltage threshold instruction is provided for the voltage of conducting between the second end of the 6th main switching device and the 3rd end of the 6th main switching device, 6th voltage threshold is greater than zero,

Wherein, this first main switching device and any one in this second main switching device are the upper pipe of the first brachium pontis in voltage transformation module breaker in middle pipe full-bridge circuit, another in this first main switching device and this second main switching device is the lower pipe of the second brachium pontis in this switching tube full-bridge circuit, 3rd main switching device and any one in the 4th main switching device are the lower pipe of this first brachium pontis, another in 3rd main switching device and the 4th main switching device is the upper pipe of this second brachium pontis, 5th main switching device and the 6th main switching device are the synchronous rectifier in this voltage transformation module.

In conjunction with the first of first aspect and first aspect to any one the possible implementation in the 8th kind of possible implementation, in the tenth kind of possible implementation of first aspect, this drive circuit also comprises:

For driving the 5th branch road of the 5th main switching device, 5th branch road comprises the 3rd secondary of the 5th storage capacitor and this first transformer be connected in series, the first end of the 5th branch road connects the first end of the 5th main switching device, second end of the 5th branch road connects the second end of the 5th main switching device, 5th main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of the 5th branch road of the 5th branch road is more than or equal to the 5th voltage threshold, second end of the 5th main switching device and the 3rd end conducting of the 5th main switching device, 5th voltage threshold instruction is provided for the voltage of conducting between the second end of the 5th main switching device and the 3rd end of the 5th main switching device, 5th voltage threshold is greater than zero.

Second aspect provides a kind of control circuit, and this control circuit comprises the drive circuit that controller and first aspect provide,

From the first moment, until the second moment,

This controller is used for, and this first switch controlled in this drive circuit in this drive circuit closes, and this second switch controlled in this drive circuit disconnects, and drives this first main switching device and the equal conducting of this second main switching device to make this drive circuit;

From this second moment, until the 3rd moment,

This controller disconnects for controlling this first switch, and controls the disconnection of this second switch, drives this first main switching device and this second main switching device from being closed into disconnection to make this drive circuit;

From the 3rd moment, until the 4th moment,

This controller disconnects for controlling this first switch, and it is closed to control this second switch, drives this first main switching device and this second main switching device all to disconnect to make this drive circuit;

From the 4th moment, until the 5th moment,

This controller disconnects for controlling this first switch, and controls the disconnection of this second switch, to make this drive circuit drive this first main switching device and this second main switching device closed from being disconnected to,

Wherein, each moment above-mentioned is different.

The third aspect provides a kind of control circuit, and this control circuit comprises the drive circuit that any one the possible implementation in the 4th kind to the 9th kind possible implementation of controller and first aspect provides,

From the first moment, until the second moment,

This controller closes for this first switch controlled in this drive circuit, and this second switch controlled in this drive circuit disconnects, and the 3rd switch controlled in this drive circuit disconnects, and the 4th switch controlled in this drive circuit closes, to make this drive circuit drive this first main switching device and this second main switching device to close, the 3rd main switching device and the 4th main switching device is driven to disconnect;

From this second moment, until the 3rd moment,

This controller disconnects for controlling this first switch, and control the disconnection of this second switch, and control the 3rd switch disconnection, and it is closed to control the 4th switch, drives this first main switching device, this second main switching device, the 3rd main switching device and the 4th main switching device all to disconnect to make this drive circuit;

From the 3rd moment, until the 4th moment,

This controller disconnects for controlling this first switch, and it is closed to control this second switch, and control the 3rd switch disconnection, and it is closed to control the 4th switch, drives this first main switching device, this second main switching device, the 3rd main switching device and the 4th main switching device all to disconnect to make this drive circuit;

From the 4th moment, until the 5th moment,

This controller disconnects for controlling this first switch, and it is closed to control this second switch, and control the 3rd switch disconnection, and control the 4th switch disconnection, to make this drive circuit drive this first main switching device and this second main switching device to disconnect, drive the 3rd main switching device and the 4th main switching device closed from being disconnected to;

From the 5th moment, until the 6th moment,

This controller disconnects for controlling this first switch, and it is closed to control this second switch, and it is closed to control the 3rd switch, and control the 4th switch disconnection, to make this drive circuit drive this first main switching device and this second main switching device to disconnect, the 3rd main switching device and the 4th main switching device is driven to close;

From the 6th moment, until the 7th moment,

This controller disconnects for controlling this first switch, and it is closed to control this second switch, and control the 3rd switch disconnection, and control the 4th switch disconnection, to make this drive circuit drive this first main switching device and this second main switching device to disconnect, drive the 3rd main switching device and the 4th main switching device from being closed into disconnection;

From the 7th moment, until the 8th moment,

From the 8th moment, until the 9th moment,

This controller disconnects for controlling this first switch, and control the disconnection of this second switch, and control the 3rd switch disconnection, and it is closed to control the 4th switch, drive this first main switching device and this second main switching device closed from being disconnected to make this drive circuit, the 3rd main switching device and the 4th main switching device is driven to disconnect

Wherein, each moment above-mentioned is different.

Fourth aspect provides a kind of device for voltage transitions, and this device comprises:

Voltage-type switching device and control circuit, the control circuit that this control circuit provides for above-mentioned second aspect or the third aspect, this control circuit is for controlling the closed of this voltage-type switching device and disconnecting.

Based on technique scheme, the drive circuit for driving switch device that the embodiment of the present invention provides, control circuit and device, the first main switching device is driven by the first branch road, the second main switching device is driven by the second branch road, this first branch road comprises the former limit of transformer, this the second branch road comprises the secondary of this transformer, namely the isolation drive of two main switching devices is achieved, without the need to requiring this two main switching device common sources or altogether, relative to prior art, the range of application of harmless Driving technique effectively can be expanded.

Accompanying drawing explanation

In order to be illustrated more clearly in the technical scheme of the embodiment of the present invention, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

Fig. 1 shows the schematic diagram of the drive circuit provided according to the embodiment of the present invention.

Fig. 2 shows another schematic diagram of the drive circuit provided according to the embodiment of the present invention.

Fig. 3 shows the schematic diagram of the work schedule of the drive circuit provided according to the embodiment of the present invention.

Fig. 4 shows a schematic diagram again of the drive circuit provided according to the embodiment of the present invention.

Fig. 5 shows a schematic diagram again of the drive circuit provided according to the embodiment of the present invention.

Fig. 6 shows another schematic diagram of the work schedule of the drive circuit provided according to the embodiment of the present invention.

Fig. 7 shows the schematic diagram of the application scenarios of the drive circuit provided according to the embodiment of the present invention.

Fig. 8 shows the schematic block diagram of the control circuit provided according to the embodiment of the present invention.

Fig. 9 shows another schematic block diagram of the control circuit provided according to the embodiment of the present invention.

Figure 10 shows the schematic block diagram of the device for voltage transitions provided according to the embodiment of the present invention.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, be clearly and completely described the technical scheme in the embodiment of the present invention, obviously, described embodiment is the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, belong to the scope of protection of the invention.

To facilitate understanding of the present embodiment of the invention, first several relevant concept is introduced at this:

1) Switching Power Supply (Switching Mode Power Supply), can be described as again exchange type power or switch converters, is a kind of high frequency device for converting electric energy.Its function is by the voltage of a position standard, is converted to the required voltage of user side or electric current through multi-form framework.Utilize modern power electronics technology, control switch pipe open and disconnect time ratio, maintain a kind of power supply of regulated output voltage.Switching Power Supply is generally by pulse width modulation (Pulse Width Modulation, referred to as " PWM ") control integration circuit (Integrated Circuit, referred to as " IC ") and metal-oxide layer semiconductcor field effect transistor, be called for short metal-oxide half field effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor,, referred to as " MOSFET ") form.

Wherein, PWM is a kind of analog control mode, it carrys out the biased of modulation transistor base stage or metal-oxide-semiconductor grid according to the change of respective loads, realize the change of transistor or metal-oxide-semiconductor ON time, thus realize the change of switching power supply output, this mode can make the output voltage of power supply keep constant when operation conditions change, is the very effective technology of one utilizing the digital signal of microprocessor to control analog circuit.

2)MOSFET

MOSFET applies more switching device, and it has higher switching speed, but also has larger parasitic capacitance simultaneously.When it turns off, under the effect of external voltage, its parasitic capacitance is full of electricity, if do not bled off by this Partial charge before it is opened, then will be consumed in device inside.

MOSFET also can referred to as metal-oxide-semiconductor.

3) harmless Driving technique, is based upon use inductance, and capacity cell realizes the storage of energy and release or energy feedback power, thus realizes harmless driving under ideal conditions.

4) Same Name of Ends of transformer, alternating current is passed to respectively at two windings, (or direct current generation stationary magnetic field), when flow direction superposition (equidirectional), the electric current of two windings flows into the Same Name of Ends that end is exactly them, and the outflow of bus current end of two windings is their another group Same Name of Ends.

Fig. 1 shows the schematic block diagram of the drive circuit 100 for driving switch device that the embodiment of the present invention provides, and this drive circuit 100 comprises:

For driving first branch road 110 of the first main switching device S1, this first branch road 110 comprises the first former limit (1Ph as shown in Figure 1 of the first storage capacitor C1 and the first transformer T1 be connected in series, 1Pl), the first end 111 of this first branch road 110 connects the first end of this first main switching device S1, second end 112 of this first branch road 110 connects second end of this first main switching device S1, second end 112 of this first branch road 110 also connects the negative pole Vcc-of power supply, this first main switching device S1 also comprises the 3rd end, wherein, when voltage difference between the first end 111 and the second end 112 of this first branch road 110 of this first branch road 110 is more than or equal to the first voltage threshold, second end of this first main switching device S1 and the 3rd end conducting of this first main switching device S1, the instruction of this first voltage threshold is provided for the voltage of conducting between second end of this first main switching device S1 and the 3rd end of this first main switching device S1, this first voltage threshold is greater than zero,

Particularly, first main switching device S1 is the target switch device that will drive, as shown in Figure 1, first main switching device S1 comprises first end, the second end and the 3rd end (three terminals 1 of S1 as shown in Figure 1 respectively, 2 and 3), wherein, the first end of the first main switching device S1 and the second end are switch control terminal, second end and the 3rd end are switch link, S1 in default situations, its second end and the 3rd end disconnect, when the voltage difference between the first end and the second end of S1 meets the first voltage threshold, and conducting between second end of S1 and the 3rd end.When voltage difference between the first end 111 and the second end 112 of the first branch road 110 is more than or equal to the first voltage threshold, be equivalent to voltage difference between the first end of S1 and the second end and meet the first voltage threshold, then switch link second end of S1 and the 3rd end conducting.The voltage difference that should be understood that between the first end 111 and the second end 112 of the first branch road 110 is less than this first voltage threshold, this first main switching device S1 is in off-state, and namely second end of S1 and the 3rd end of S1 disconnect.More specifically, this first main switching device S1 can be metal-oxide-semiconductor, accordingly, the grid g of S1 is the first end of S1, the source electrode s of S1 is second end of S1, and the drain electrode d of S1 is the 3rd end of S1, specifically as shown in Figure 2, wherein this first voltage threshold also can be referred to as the driving voltage threshold value of metal-oxide-semiconductor S1, and the driving voltage threshold value of such as current metal-oxide-semiconductor is 0.4v to 0.7v.

First auxiliary switch device Q1, the first end of this first auxiliary switch device Q1 connects the first end 111 of this first branch road 110, second end of this first auxiliary switch device Q1 connects the positive pole Vcc+ of this power supply, this the first auxiliary switch device Q1 comprises the first K switch 1 and the first parasitic capacitance Cd1 in parallel, wherein, when this first K switch 1 is closed, the first end 111 of this first branch road 110 is connected with the positive pole Vcc+ of this power supply by this closed first K switch 1, when this first K switch 1 disconnects, the first end 111 of this first branch road 110 is connected with the positive pole Vcc+ of this power supply by this first parasitic capacitance Cd1,

Second auxiliary switch device Q2, the first end of this second auxiliary switch device Q2 connects the first end 111 of this first branch road 110, second end of this second auxiliary switch device Q2 connects the negative pole Vcc-of this power supply, this the second auxiliary switch device Q2 comprises second switch K2 in parallel and the second parasitic capacitance Cd2, wherein, when this second switch K2 is closed, the first end 111 of this first branch road 110 is connected with the negative pole Vcc-of this power supply by closed this second switch K2, when this second switch K2 disconnects, the first end 111 of this first branch road 110 is connected with the negative pole Vcc-of this power supply by this second parasitic capacitance Cd2,

Particularly, by control Q1, Q2 conducting and disconnection, the voltage difference between the first end 111 of the first branch road 110 and the second end 112 can be controlled, thus realize the harmless driving to S1 and S2.

Particularly, Q1 and Q2 can be metal-oxide-semiconductor, the equivalent model of metal-oxide-semiconductor as shown in Figure 2, above-mentioned first K switch 1 corresponds to the equivalent switch between the drain electrode d of metal-oxide-semiconductor Q1 and source electrode s, first parasitic capacitance Cd1 corresponds to the parasitic capacitance Cds1 between the drain electrode d of metal-oxide-semiconductor Q1 and source electrode s, second switch K2 corresponds to the equivalent switch between the drain electrode d of metal-oxide-semiconductor Q2 and source electrode s, and the second parasitic capacitance Cd2 corresponds to the parasitic capacitance Cds2 between the drain electrode d of metal-oxide-semiconductor Q2 and source electrode s.

For driving second branch road 120 of the second main switching device S2, this second branch road 120 comprises the first secondary (1Ah as shown in Figure 1 of the second storage capacitor C2 and this first transformer T1 be connected in series, 1Al), the first end of this second branch road 120 connects the first end of this second main switching device S2, second end of this second branch road 120 connects second end of this second main switching device S2, wherein, this second main switching device S2 also comprises the 3rd end, when voltage difference between the first end and the second end of this second branch road 120 of this second branch road 120 is more than or equal to the second voltage threshold, second end of this second main switching device S2 and the 3rd end conducting of this second main switching device S2, the instruction of this second voltage threshold is provided for the voltage of conducting between second end of this second main switching device S2 and the 3rd end of this second main switching device S2, this second voltage threshold is greater than zero.

Particularly, the second main switching device S2 is the target switch device that will drive, the operation principle of S2 and type identical with the first main switching device S1, for simplicity, repeat no more here, wherein, when S1 and S2 is switching device of the same type, the first voltage threshold is identical with the second voltage threshold.

For the ease of understanding and describing, be hereinafter metal-oxide-semiconductor for S1, S2, Q1 and Q2 and be described.

In the drive circuit 100 that the embodiment of the present invention provides, when Q1 closes (the first K switch 1 be equivalent in Q1 closes), when Q2 disconnects (the second switch K2 be equivalent in Q2 disconnects), the first end 111 of the first branch road 110 directly connects Vcc+, voltage difference U gs1 (also can be referred to as the driving voltage of S1) between the grid g of S1 and source electrode s is more than or equal to the driving voltage threshold value (being equivalent to the first voltage threshold) of S1, conducting between the drain electrode d of S1 and source electrode s, also can be referred to as S1 and be in conducting state; Utilize the former limit of the first transformer T1 and the excitation principle of secondary coil winding, in the second branch road, the first end 1Ah of the second secondary and the second end 1Al is equivalent to positive pole and the negative pole of power supply, voltage difference U gs2 (also can be referred to as the driving voltage of S2) between the grid g of S2 and source electrode s is more than or equal to the driving voltage threshold value (being equivalent to the second voltage threshold) of S2, conducting between the drain electrode d of S2 and source electrode s, closes hereinafter referred to as S2.When Q1 disconnects (the first K switch 1 be equivalent in Q1 disconnects), when Q2 closes (the second switch K2 be equivalent in Q2 closes), the first end 111 of the first branch road 110 directly connects Vcc-, the driving voltage Ugs1 of S1 is lower than the driving voltage threshold value (the first voltage threshold) of S1, the drain electrode d of S1 and the separated of source electrode s, also can be referred to as S1 and be in off-state; Meanwhile, due to the first transformer T1 refusal of excitation, the driving voltage Ugs2 of S2 is lower than the driving voltage threshold value (the second voltage threshold) of S2, and the drain-source pole of S2 separated, namely S2 is in off-state.Should understand, in the situation closed from Q1, Q2 disconnects, disconnect to Q1, in the process of situation that Q2 closes, also comprise the situation that Q1 disconnects, Q2 also disconnects, namely Q1 and Q2 is all in the situation in dead band, and in this process, the grid source electric capacity Cgs1 of S1 constantly discharges to the first storage capacitor C1, namely constantly by the energy trasfer on Cgs1 on C1, namely the driving voltage Ugs1 of S1 constantly declines; Similarly, in this case, the grid source electric capacity Cgs2 of S2 also constantly discharges to the second storage capacitor C2, and the driving voltage Ugs2 of S2 constantly declines, this process be S1 and S2 from the process being conducting to disconnection.In the situation disconnected from Q1, Q2 is closed, close to Q1, Q2 disconnect situation process in, also the situation that Q1 disconnects, Q2 also disconnects is comprised, in this process, first storage capacitor C1 constantly discharges to the grid source electric capacity Cgs1 of S1, namely constantly by the energy trasfer on C1 on Cgs1, namely the driving voltage Ugs1 of S1 constantly rises; Similarly, in this case, the second storage capacitor C2 also constantly discharges to the grid source electric capacity Cgs2 of S2, and the driving voltage Ugs2 of S2 constantly rises, this process be S1 and S2 from the process being disconnected to conducting.Should be understood that namely said process achieves the harmless driving of S1 and S2.

Therefore, the drive circuit 100 for driving switch device that the embodiment of the present invention provides, the harmless driving of switching device S1 and S2 can be realized, adopt transformer simultaneously, achieve the isolation drive of switching device S1 and S2, namely must common source or altogether without the need to limiting S1 and S2, particularly, such as S1 can be the main switch in Switching Power Supply, S2 can be the synchronous rectifier in Switching Power Supply, the i.e. drive circuit that provides of the embodiment of the present invention, relative to existing harmless drive circuit topology, can expand the range of application of harmless Driving technique.

In addition, the drive circuit that the embodiment of the present invention provides, the negligible amounts of the auxiliary switch device of needs, circuit cost is lower, such as in the embodiment described in Fig. 1 and Fig. 2, by controlling two auxiliary switch device Q1 and Q2, just can realize the harmless driving to two main switching device S1 and S2.

Should understand, in embodiments of the present invention, as shown in Figure 1, the first end 1Ph on the first former limit of the first transformer T1 and the first end 1Ah of the first secondary is Same Name of Ends, namely, when the first end 1Ph on the first former limit is high potential, the first end 1Ah of the first secondary is also high potential.In the first branch road 110, the first end 1Ph on the first former limit of the first transformer T1 is close to the first end 111 of the first branch road 110 relative to its second end 1Pl; In the second branch road 120, the first end 1Ah of first secondary of the first transformer T1 is close to the first end 121 of the second branch road 120 relative to its second end 1Al.Should understand, when voltage difference between the first end 111 and the second end 112 of the first branch road 110 is greater than first voltage threshold of S1, utilize the former limit of the first transformer T1 and the excited work principle of secondary, can realize in the second branch road 120, voltage difference between the first end 121 of the second branch road 120 and the second end 122 is greater than second voltage threshold of S2, therefore, utilize the drive circuit that the embodiment of the present invention provides, conducting and simultaneously disconnecting while S1 and S1 can be realized.

Will also be understood that, in the first branch road 110, connect mutually with the first storage capacitor C1 in the first former limit of the first transformer T1, be not limited to the order of connection shown in Fig. 1 and Fig. 2, such as the first storage capacitor C1 can be connected between the first end Ph on this first former limit and the first end 111 of the first branch road 110.In like manner, in the second branch road 120, first secondary of the first transformer T2 is connected mutually with the second storage capacitor C2, is not limited to the order of connection shown in Fig. 1 and Fig. 2, and such as C2 can be connected between the second end Al of this first secondary and the second end 122 of the second branch road 120.

Alternatively, in the invention process, the first auxiliary switch device Q1 also comprises the diode of the reversal connection in parallel with the first K switch 1 and the first parasitic capacitance Cd1, as shown in Figure 1 or 2.Particularly, Q1 can by relay, electric capacity and/or and the switch module (equivalent structure of the metal-oxide-semiconductor such as shown in Fig. 2) that diode forms, Q1 can be also directly metal-oxide-semiconductor (as shown in Figure 2), and the embodiment of the present invention is not construed as limiting this.Said circumstances is equally applicable to the second auxiliary switch device Q2, for simplicity, repeats no more here.

What should be understood that the Q1 that relates to closed (or disconnection) and the first K switch 1 in Q1 close that (or disconnection) state herein is the identical meaning; Q2 closed (or disconnection) is the identical meaning with second switch K2 in Q2 closed (or disconnection).

Alternatively, in the invention process, this first main switching device S1, this second main switching device S2, this first auxiliary switch device Q1 and this second auxiliary switch device Q2 are metal-oxide layer semiconductcor field effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor, referred to as " MOSFET "), can referred to as metal-oxide-semiconductor.

As shown in Figure 2, alternatively, in embodiments of the present invention, this drive circuit 100 also comprises:

Act on the first control signal input E1 of this first auxiliary switch device Q1, the first control signal that this first control signal input E1 inputs is used for, and controls the closed of this first K switch 1 and disconnects;

Act on the second control signal input E2 of this second auxiliary switch device Q2, the second control signal that this second control signal input E2 inputs is used for, and controls the closed of this second switch K2 and disconnects.

Particularly, this the first control signal input E1 acts on the control end of conducting between the first end for control Q1 of Q1 and the second end and disconnection, such as Q1 is metal-oxide-semiconductor, this the first control signal input E1 acts on the grid g of metal-oxide-semiconductor Q1, one end in the first end of Q1 and the second end is the drain electrode d of metal-oxide-semiconductor, and the other end is source electrode s.Similar, this the second control signal input E2 acts on the control end of conducting between the first end for control Q2 of Q2 and the second end and disconnection, such as Q2 is metal-oxide-semiconductor, this the second control signal input E2 acts on the grid g of metal-oxide-semiconductor Q2, one end in the first end of Q2 and the second end is the drain electrode d of metal-oxide-semiconductor, and the other end is source electrode s.

Should understand, above-mentioned first control signal input E1 acts on the first auxiliary switch device Q1, the second control signal input E2 acts on the second auxiliary switch device Q2, only represent that control signal input has the function controlling each self-corresponding switching device, not represents that these control signal inputs and each self-corresponding switching device necessarily exist direct annexation.In practical application, this the first control signal input E1 directly can connect the grid g of Q1, also the grid g of Q1 can indirectly be acted on, in like manner, this the second control signal input E2 also directly can connect the grid g of Q2, and also indirectly can act on the grid g of Q2, the embodiment of the present invention is not construed as limiting this, as long as ensure that the control signal of E1 input can the closed and disconnected of control Q1, the control signal of E2 input can the closed and disconnected of control Q2.

Particularly, the control signal that this first control signal input E1 and the second control signal input E2 inputs is pulse width modulation (PWM) signal.

Suppose that Q1 and Q2 is N-channel MOS pipe, with the first control signal of E1 input for the PWM1 shown in Fig. 3, second control signal of E2 input is PWM2 as shown in Figure 3 is example, below in conjunction with the logic timing figure shown in Fig. 3, describes the course of work of the drive circuit 100 shown in Fig. 2.

As shown in Figure 3, alternatively, in embodiments of the present invention,

From the first moment t1, until the second moment t2, this first control signal specifically for, control this first K switch 1 and close, and this second control signal specifically for, control this second switch K2 and disconnect;

Particularly, PWM1 is high level, and PWM2 is low level, Q1 closes, and Q2 disconnects, and the first end 111 of the first branch road 110 directly connects Vcc+, the driving voltage Ugs1 of S1 meets the driving voltage threshold value (corresponding to the first voltage threshold) of S1, such as 0.4v-0.7v, S1 conducting.Meanwhile, the first transformer T1 excitation, the 1Ah end of the first secondary is high potential, and 1Al is electronegative potential, and namely the driving voltage Ugs2 of S2 meets the driving voltage threshold value (corresponding to the second voltage threshold) of S2, S2 conducting.

It should be noted that, it is have certain time delay that the first K switch 1 closes between S1 conducting, this is because transmission needs the time in electrical signal online road, this point belongs to common practise to those skilled in the art, repeats no more herein.In the technical scheme that the embodiment of the present invention provides, that supposition is the first K switch 1 is closed while, S1 is with regard to conducting, also namely have ignored the first K switch 1 closed with S1 conducting between time delay (this time delay is normally very little, user awareness less than), but it is convenient that this is only statement, negated not objective fact.

From this second moment t2, until the 3rd moment t3, this first control signal specifically for, control this first K switch 1 and disconnect, and this second control signal specifically for, control this second switch K2 and disconnect;

Particularly, PWM1 is low level, PWM2 is low level, Q1 disconnects, Q2 disconnects, the first end 111 of the first branch road 110 connects Vcc+ by the drain-source electrode capacitance Cds1 of Q1, Vcc-is connected by the Cds2 of Q2, the drain source capacitance Cds1 of Q1 charges, the drain source capacitance Cds2 of Q2 discharges, voltage difference between the first end 111 of the first branch road 110 and the second end 112 constantly reduces, the charging current iC1 of C1 starts to reduce, energy transferring is given the first storage capacitor C1 by the grid source electric capacity Cgs1 of S1 always, energy transferring is given the second storage capacitor C2 by the grid source capacitance Cgs2 of S2 always, the driving voltage of S1 and S2, namely Ugs1 and Ugs2 declines gradually, the drive current of S1 and S2, namely ig1 and ig2 is negative value.

This t2 to t3 be S1 and S2 from being conducting to the process disconnected completely.

From the 3rd moment t3, until the 4th moment t4, this first control signal specifically for, control this first K switch 1 and disconnect, and this second control signal specifically for, control this second switch K2 close;

Particularly, PWM1 is low level, and PWM2 is high level, and Q1 disconnects, and Q2 closes, and the first end 111 of the first branch road 110 directly connects Vcc-, and the charging current iC1 of C1 constantly reduces, until oppositely increase.Voltage difference between the first end 111 of the first branch road 110 and the second end 112 is less than the driving voltage threshold value (corresponding to the first voltage threshold) of S1, namely the driving voltage Ugs1 of S1 does not meet the driving voltage threshold value (corresponding to the first voltage threshold) of S1, and S1 disconnects; The driving voltage Ugs2 of S2 does not meet the driving voltage threshold value (corresponding to the second voltage threshold) of S2 yet, and S2 disconnects.

Same, it should be noted that, it is have certain time delay that the first K switch 1 disconnects between S1 disconnection, this is because transmission needs the time in electrical signal online road, this point belongs to common practise to those skilled in the art, repeats no more herein.In the technical scheme that the embodiment of the present invention provides, that supposition is the first K switch 1 disconnects while, S1 is just disconnected, also namely have ignored the first K switch 1 disconnect with S1 disconnect between time delay (this time delay is normally very little, user awareness less than), but it is convenient that this is only statement, negated not objective fact.

From the 4th moment t4, until the 5th moment t5, this first control signal specifically for, control this first K switch 1 and disconnect, and this second control signal specifically for, control this second switch K2 and disconnect,

Particularly, PWM1 is low level, PWM2 is low level, Q1 disconnects, Q2 disconnects, and the first end 111 of the first branch road 110 is connected Vcc-, Vcc+ by the drain-source electrode capacitance Cds2 of Q2 and charged to the drain source capacitance Cds2 of Q2 by the drain source capacitance Cds1 of Q1, voltage difference between the first end 111 of the first branch road 110 and the second end 112 constantly raises, the charging current iC1 bottom out of C1.The grid source electric capacity Cgs1 of S1 starts to charge (comprising C1 to charge to Cgs1) always, and the driving voltage Ugs1 of S1 increases gradually, and the drive current ig1 of S1 is just; First transformer T1 exciting curent increases gradually, and the grid source electric capacity Cgs2 of S2 starts charging (comprising C2 always to Cgs2 charging), and namely the driving voltage Ugs2 of S2 increases gradually, and the drive current ig2 of S2 is just.

This t4 to t5 be S1 and S2 from the process being disconnected to complete conducting.

Wherein, each moment above-mentioned is different.

State between t1 to t5 described in above-mentioned composition graphs 3 is a work period, the logic state that can circulate between above-mentioned t1 to t5 from the t5 moment.As shown in Figure 6, the logic state from t5 to t6 is identical with the logic state from t1 to t2.

Particularly, for S1, at S1 from being conducting to the process that disconnects completely, energy in S1 on the electric capacity Cgs1 of grid source is constantly transferred on the first storage capacitor C1, the driving voltage of S1 declines gradually, until be less than the driving voltage threshold value (such as 0.7v) of S1, S1 thoroughly disconnects; At S1 from the process being disconnected to complete conducting, the energy of the upper storage of C1 is transferred to again on the grid source electric capacity Cgs1 of S1, and the driving voltage of S1 constantly increases, until be equal to, or greater than its driving voltage threshold value, and the complete conducting of S1, thus the harmless driving achieving S1.In above process, the process that the drain source capacitance Cds of Q1 and Q2 also charges, discharges, the energy that the drain source capacitance Cds2 of Q2 discharges also is stored in the first storage capacitor C1, thus make, at S1 from the process being disconnected to conducting, C1 by more energy transferring on the grid source electric capacity Cgs1 of S1, be conducive to improve S1 from the speed being disconnected to conducting.

Therefore, the drive circuit that the embodiment of the present invention provides, can realize the harmless driving of switching device effectively, can also realize the isolation drive of two switching devices simultaneously, must common source or altogether without requiring two switching devices, effectively can improve the universality of harmless drive circuit.

In above-mentioned composition graphs 1 and the embodiment shown in Fig. 2, first transformer T1 comprises a vice-side winding (the first secondary), in the drive circuit 100 that the embodiment of the present invention provides, by the number of increase by first transformer T1 vice-side winding, the number of driven main switching device can also be increased.

As shown in Figure 4, alternatively, in embodiments of the present invention, this drive circuit 100 also comprises:

For driving the 5th branch road 150 of the 5th main switching device S5, 5th branch road 150 comprises the 3rd secondary (1Bh as shown in Figure 4 of the 5th storage capacitor C5 and this first transformer T1 be connected in series, 1Bl), the first end 151 of the 5th branch road 150 connects the first end of the 5th main switching device S5, second end 152 of the 5th branch road 150 connects second end of the 5th main switching device S5, wherein, 5th main switching device S5 also comprises the 3rd end, when voltage difference between the first end 151 and the second end 152 of the 5th branch road 150 of the 5th branch road 150 is more than or equal to the 5th voltage threshold, second end of the 5th main switching device S5 and the 3rd end conducting of the 5th main switching device S5, 5th voltage threshold instruction is provided for the voltage of conducting between second end of the 5th main switching device S5 and the 3rd end of the 5th main switching device S5, and the 5th voltage threshold is greater than zero.

Particularly, the 5th main switching device S5 can be metal-oxide-semiconductor, and the first end of the S5 in the embodiment of the present invention corresponds to the grid g of metal-oxide-semiconductor S5, and second end of S5 corresponds to the source electrode s of metal-oxide-semiconductor S5, and the 3rd end of S5 corresponds to the drain electrode d of metal-oxide-semiconductor.Should be understood that the source electrode s of metal-oxide-semiconductor S5 is connected in application circuit, such as, in the control circuit of Switching Power Supply with drain electrode d.

Should be understood that the first end 1Bh of the 3rd secondary of the first transformer and the first end 1Ah on the first former limit is Same Name of Ends.

Particularly, the work schedule (work schedule as shown in Figure 3) of S5 and S1, S2 is consistent, for simplicity, repeats no more here.

Above-mentioned known, the circuit connection structure of the drive circuit that the embodiment of the present invention provides to driven main switching device does not have very strict restrictive condition, such as S1, S2 and S5 are without the need to common source each other or altogether, can be such as three switching devices be isolated from each other, the range of application of harmless drive circuit can be expanded.

In the drive circuit shown in Fig. 4, by controlling two auxiliary switch device Q1 and Q2, just can realize the harmless driving to three main switching devices S1, S2 and S3.For the ease of understanding and describing, Fig. 4 only schematically illustrates the first transformer T1 and comprises two vice-side winding (the first secondary (1Ah, 1Al) He three secondary (1Bh, schematic diagram 1Bl)), should understand, in embodiments of the present invention, can by continuing the vice-side winding number of increase by first transformer T1, increase the number of driven switching device, the embodiment of the present invention is not construed as limiting this, namely in the drive circuit provided in the embodiment of the present invention, by controlling two auxiliary switch device Q1 and Q2, the harmless driving of the main switching device to greater number can be realized.Therefore, the drive circuit that the embodiment of the present invention provides, circuit cost is lower, and circuit operational efficiency is high.

For the ease of understanding and describing, all be metal-oxide-semiconductor for the first main switching device S1 and the second main switching device S2 to be above described, this the first main switching device S1 and the second main switching device S2 can also be other voltage-type driving switch device, and the embodiment of the present invention is not construed as limiting this.

Drive circuit shown in Fig. 1, Fig. 2 and Fig. 4, can adopt identical logic state to drive multiple main switching device, in embodiments of the present invention, by the expansion to circuit, can realize adopting different logic states to drive more main switching device.Supposing the drive circuit 100 shown in Fig. 1 or Fig. 2 to be labeled as drive circuit elementary cell, in embodiments of the present invention, can, by increasing the number of this drive circuit elementary cell, realizing adopting different logic states to drive multiple main switching device.

Fig. 5 shows the drive circuit 200 for driving switch device that another embodiment of the present invention provides, this drive circuit 200 comprises two drive circuits 100 (as being labeled as drive circuit elementary cell in Fig. 5) as shown in Figure 2, particularly, this drive circuit 200 comprises:

For driving the 3rd branch road 130 of the 3rd main switching device S3, 3rd branch road 130 comprises the second former limit (2Ph as shown in Figure 5 of the 3rd storage capacitor C3 and the second transformer T2 be connected in series, 2Pl), the first end 131 of the 3rd branch road 130 connects the first end of the 3rd main switching device S3, second end 132 of the 3rd branch road 130 connects second end of the 3rd main switching device S3, second end 132 of the 3rd branch road 130 also connects the negative pole Vcc-of this power supply, 3rd main switching device S3 also comprises the 3rd end, wherein, when voltage difference between the first end 131 and the second end 132 of the 3rd branch road 130 of the 3rd branch road 130 is more than or equal to tertiary voltage threshold value energy, second end of the 3rd main switching device S3 and the 3rd end conducting of the 3rd main switching device S3, the instruction of this tertiary voltage threshold value is provided for the voltage of conducting between second end of the 3rd main switching device S3 and the 3rd end of the 3rd main switching device S3, this tertiary voltage threshold value is greater than zero,

3rd auxiliary switch device Q3, the first end of the 3rd auxiliary switch device Q3 connects the first end 131 of the 3rd branch road 130, second end of the 3rd auxiliary switch device Q3 connects the positive pole Vcc+ of this power supply, 3rd auxiliary switch device Q3 comprises the 3rd K switch 3 in parallel and trixenie electric capacity Cd3, wherein, when the 3rd K switch 3 is closed, the first end 131 of the 3rd branch road 130 is connected with the positive pole Vcc+ of this power supply by the 3rd closed K switch 3, when the 3rd K switch 3 disconnects, the first end of the 3rd branch road 130 is connected with the positive pole Vcc+ of this power supply by this trixenie electric capacity Cd3,

4th auxiliary switch device Q4, the first end of the 4th auxiliary switch device Q4 connects the first end 131 of the 3rd branch road 130, second end of the 4th auxiliary switch device Q4 connects the negative pole Vcc-of this power supply, 4th auxiliary switch device Q4 comprises the 4th K switch 4 in parallel and the 4th parasitic capacitance Cd4, wherein, when the 4th K switch 4 is closed, the first end 131 of the 3rd branch road 130 is connected with the negative pole Vcc-of this power supply by the 4th closed K switch 4, when the 4th K switch 4 disconnects, the first end 131 of the 3rd branch road 130 is connected with the negative pole Vcc-of this power supply by the 4th parasitic capacitance Cd4,

For driving the 4th branch road 140 of the 4th main switching device S4, 4th branch road 140 comprises the second secondary (2Ah as shown in Figure 5 of the 4th storage capacitor C4 and this second transformer T2 be connected in series, 2Al), the first end 141 of the 4th branch road 140 connects the first end of the 4th main switching device S4, second end 142 of the 4th branch road 140 connects second end of the 4th main switching device S4, wherein, 4th main switching device S4 also comprises the 3rd end, when voltage difference between the first end 141 and the second end 142 of the 4th branch road 140 of the 4th branch road 140 is more than or equal to the 4th voltage threshold, second end of the 4th main switching device S4 and the 3rd end conducting of the 4th main switching device S4, 4th voltage threshold instruction is provided for the voltage of conducting between second end of the 4th main switching device S4 and the 3rd end of the 4th main switching device S4, 4th voltage threshold is greater than zero.

Particularly, main switching device S1, S2, S3 and S4 are the target switch device that will drive, and particularly, S1, S2, S3 and S4 are N-channel MOS pipe, are grid g for the first end of S1, S1, and the second end is source electrode s, and the 3rd end is drain electrode d.The first end 111 of the first branch road 110 connects the grid g of S1, second end 112 of the first branch road 110 connects the source electrode s of S1, when voltage difference between the first end 111 and the second end 112 of the first branch road 110 is more than or equal to driving voltage threshold value (corresponding to first voltage threshold) of S1, driving voltage Ugs1 between the grid source electrode being equivalent to S1 reaches the driving voltage threshold value of S1, i.e. conducting between the drain electrode d of S1 and source electrode s.Should understand, voltage difference between the first end 111 and the second end 112 of the first branch road 110 is less than driving voltage threshold value (corresponding to first voltage threshold) of S1, the i.e. drain electrode d of S1 and the separated of source electrode s, namely this S1 is in off-state.Should be understood that drain electrode d and the source electrode s of S1 are connected in application circuit, such as, in the control circuit of Switching Power Supply.Similar, foregoing description is equally applicable to S2, S3 and S4, for simplicity, repeats no more here.

Particularly, Q1, Q2, Q3 and Q4 are auxiliary switch device, by control Q1, Q2 conducting and disconnection, can control the voltage difference between the first end 111 of the first branch road 110 and the second end 112, thus realize the harmless driving to S1 and S2; By conducting and the disconnection of control Q3 and Q4, the voltage difference between the first end 131 of the 3rd branch road 130 and the second end 132 can be controlled, thus realize the harmless driving to S3 and S4.Q1, Q2, Q3 and Q4 can be metal-oxide-semiconductor, for Q1, the first parasitic capacitance Cd1 that Q1 comprises corresponds to the parasitic capacitance Cds1 between the drain electrode d of metal-oxide-semiconductor Q1 and source electrode s, and the first K switch 1 that Q1 comprises corresponds to the equivalent switch (equivalent model of metal-oxide-semiconductor as shown in Figure 5) of metal-oxide-semiconductor Q1.Foregoing description is equally applicable to Q2, Q3 and Q4, for simplicity, repeats no more here.

Alternatively, as shown in Figure 5, in embodiments of the present invention, this first main switching device S1, this second main switching device S2, the 3rd main switching device S3, the 4th main switching device S4, this first auxiliary switch device Q1, this second auxiliary switch device Q2, the 3rd auxiliary switch device Q3 and the 4th auxiliary switch device Q4 are MOS type field effect transistor MOSFET.

Alternatively, as shown in Figure 5, in embodiments of the present invention, this drive circuit 200 also comprises:

Act on the second control signal input E2 of this second auxiliary switch device Q2, the second control signal that this second control signal input E2 inputs is used for, and controls the closed of this second switch K2 and disconnects;

Act on the 3rd control signal input E3 of the 3rd auxiliary switch device Q3, the 3rd control signal that the 3rd control signal input E3 inputs is used for, and controls the closed of the 3rd K switch 3 and disconnects;

Act on the 4th control signal input E4 of the 4th auxiliary switch device Q4, the 4th control signal that the 4th control signal input E4 inputs is used for, and controls the closed of the 4th K switch 4 and disconnects.

Particularly, this the first control signal input E1 acts on the control end of conducting between the first end for control Q1 of Q1 and the second end and disconnection, such as Q1 is metal-oxide-semiconductor, this the first control signal input E1 acts on the grid g of metal-oxide-semiconductor Q1, one end in the first end of Q1 and the second end is the drain electrode d of metal-oxide-semiconductor, and the other end is source electrode s.Similar, this second control signal input E2 acts on the grid g of metal-oxide-semiconductor Q2, and the one end in the first end of Q2 and the second end is the drain electrode d of metal-oxide-semiconductor, and the other end is source electrode s; 3rd control signal input E3 acts on the grid g of metal-oxide-semiconductor Q3, and the one end in the first end of Q3 and the second end is the drain electrode d of metal-oxide-semiconductor, and the other end is source electrode s; 4th control signal input E4 acts on the grid g of metal-oxide-semiconductor Q4, and the one end in the first end of Q4 and the second end is the drain electrode d of metal-oxide-semiconductor, and the other end is source electrode s.

Should understand, above-mentioned first control signal input E1 acts on the first auxiliary switch device Q1, the second control signal input E2 acts on the second auxiliary switch device Q2, the 3rd control signal input E3 acts on the 3rd auxiliary switch device Q3, the 4th control signal input E4 acts on the 4th auxiliary switch device Q4, only represent that these four control signal inputs have the function controlling each self-corresponding switching device, not represent that these control signal inputs and each self-corresponding switching device necessarily exist direct annexation.In practical application, this the first control signal input E1 directly can connect the grid g of Q1, also indirectly can act on the grid g of Q1, in like manner, this the second control signal input E2 also directly can connect the grid g of Q2, also indirectly can act on the grid g of Q2; 3rd control signal input E3 also directly can connect the grid g of Q3, also indirectly can act on the grid g of Q3; 4th control signal input E4 also directly can connect the grid g of Q4, also the grid g of Q4 can indirectly be acted on, the embodiment of the present invention is not construed as limiting this, as long as ensure that the control signal of E1 input can the closed and disconnected of control Q1, the control signal of E2 input can the closed and disconnected of control Q2, the control signal of E3 input can the closed and disconnected of control Q3, and the control signal of E4 input can the closed and disconnected of control Q4.

Particularly, the control signal of E1, E2, E3 and E4 input is pulse width modulation (PWM) signal.

Alternatively, in embodiments of the present invention, E3 and E1 is same control signal input, and E1 input the first control signal for the PWM1 shown in Fig. 3, E4 and E2 be same control signal input, its E2 input the second control signal be the PWM2 shown in Fig. 3.Particularly, the Ugs1 shown in Fig. 3 indicates S1 simultaneously, the change sequential of the driving voltage of S2, S3 and S4, namely adopts identical logic state to drive S1, S2, S3 and S4.

Alternatively, in embodiments of the present invention, E1, E2, E3 and E2 are different control signal inputs, and the logical sequence of its control signal inputted separately is also incomplete same, and namely the conducting of Q1, Q2, Q3 and Q4 is incomplete same with closed state.

Alternatively, in embodiments of the present invention, conducting when Q3 with Q1 is different, in other words, the 3rd K switch 3 does not close with this first K switch 1 simultaneously.

Particularly, conducting when control signal control Q1 with Q3 of E1 with E3 input is different.

Suppose that Q1, Q2, Q3 and Q4 are N-channel MOS pipe, the 4th control signal that the 3rd control signal that the second control signal inputted for PWM1, E2 shown in Fig. 6 for the first control signal of E1 input inputs for PWM2, E3 shown in Fig. 6 inputs for PWM3, E4 shown in Fig. 6 is for PWM4 shown in Fig. 6, below in conjunction with the logic timing figure shown in Fig. 6, the course of work of the drive circuit 200 shown in Fig. 5 is described.

From the first moment t1, until the second moment t2, this first control signal is used for, control this first K switch 1 to close, and this second control signal is used for, and controls this second switch K2 and disconnects, and the 3rd control signal is used for, control the 3rd K switch 3 to disconnect, and the 4th control signal is used for, controls the 4th K switch 4 and close;

Particularly, between this t1 to t2, PWM1 is high level, Q1 conducting; PWM2 is low level, and Q2 disconnects; The first end 111 of the first branch road 110 directly connects Vcc+, and the charging current iC1 of C1 constantly increases; Voltage difference between the first end 111 of the first branch road 110 and the second end 112 meets the driving voltage threshold value (corresponding to the first voltage threshold) of S1, and namely the driving voltage Ugs1 of S1 meets its driving voltage threshold value, S1 conducting; First transformer T1 excitation, exciting current rises, and the driving voltage Ugs2 of S2 also meets its driving voltage threshold value, S2 conducting.

PWM3 is low level, and Q3 disconnects, and PWM4 is high level, Q4 conducting; The first end 131 of the 3rd branch road 130 directly connects Vcc-, and the charging current iC3 of C3 constantly reduces, until oppositely increase; Voltage difference between the first end 131 of the 3rd branch road 130 and the second end 132 is lower than the driving voltage threshold value (corresponding to tertiary voltage threshold value) of S3, namely the driving voltage Ugs3 of S3 is lower than its driving voltage threshold value, S3 disconnects, the exciting current of the second transformer T2 declines, the driving voltage Ugs4 of S4 is also lower than its driving voltage threshold value, and S4 disconnects.

Circuit state between above-mentioned t1 to t2 can be referred to as mode one.

From this second moment t2, until the 3rd moment t3, this first control signal is used for, control this first K switch 1 to disconnect, and this second control signal is used for, controls this second switch K2 and disconnect, and the 3rd control signal is used for, control the 3rd K switch 3 to disconnect, and the 4th control signal is used for, controls the 4th K switch 4 and close;

Particularly, between this t2 to t3, PWM1 is low level, and PWM2 continues as low level, and Q1 disconnects, and Q2 disconnects, and the first end 111 of the first branch road 110 connects Vcc+ by the drain source capacitance Cds1 of Q1, connects Vcc-by the drain source capacitance Cds2 of Q2.The Cds1 charging of Q1, the Cds2 electric discharge of Q2, particularly, the drain source capacitance Cds2 of Q2 is by energy transferring to C1, and the voltage difference between the first end 111 of the first branch road 110 and the second end 112 constantly reduces, and the charging current iC1 of C1 starts to reduce.S1 grid source capacitance Cgs1 always by energy transferring to C1, namely the driving voltage Ugs1 of S1 declines gradually, and the drive current ig1 of S1 is negative value; The grid source capacitance Cgs1 energy transferring of S2 is to C2, and namely the driving voltage Ugs2 of S2 declines gradually, and the drive current ig2 of S2 is negative value.This process can be referred to as S1 and S2 from being conducting to disconnection process.

Between this t2 to t3, PWM3 is low level, and PWM4 is high level, and Q3 disconnects, and Q4 closes; The first end 131 of the 3rd branch road 130 is directly connected with Vcc-, and the charging current iC3 of C3 constantly reduces, until oppositely increase.Voltage difference between the first end 131 of the 3rd branch road 130 and the second end 132 is less than the driving voltage threshold value (corresponding to tertiary voltage threshold value) of S3, namely the driving voltage UgS3 of S3 does not meet the driving voltage threshold value (corresponding to the first voltage threshold) of S3, and S3 disconnects; The driving voltage UgS4 of S4 does not meet the driving voltage threshold value (corresponding to the second voltage threshold) of S4 yet, and S4 disconnects.

Circuit state between above-mentioned t2 to t3 can be referred to as mode two.

From the 3rd moment t3, until the 4th moment t4, this first control signal is used for, control this first K switch 1 to disconnect, and this second control signal is used for, controls this second switch K2 and close, and the 3rd control signal is used for, control the 3rd K switch 3 to disconnect, and the 4th control signal is used for, controls the 4th K switch 4 and close;

Particularly, between t3 to t4, PWM1 is low level, and PWM2 is high level, and Q1 disconnects, and Q2 closes, and the first end 111 of the first branch road 110 directly connects Vcc-, and the positive charge current i C1 of C1 constantly reduces; Voltage difference between the first end 111 of the first branch road 110 and the second end 112 is less than the driving voltage threshold value (corresponding to the first voltage threshold) of S1, namely the driving voltage Ugs1 of S1 does not meet the driving voltage threshold value (corresponding to the first voltage threshold) of S1, and S1 disconnects; The driving voltage Ugs2 of S2 does not meet the driving voltage threshold value (corresponding to the second voltage threshold) of S2 yet, and S2 disconnects.

Between this t2 to t3, PWM3 is low level, and PWM4 is high level, and Q3 disconnects, and Q4 closes.The first end 131 of the 3rd branch road 130 is directly connected with Vcc-, and the charging current iC3 of C3 continues to reduce, to oppositely increasing.Voltage difference between the first end 131 of the 3rd branch road 130 and the second end 132 is less than the driving voltage threshold value (corresponding to tertiary voltage threshold value) of S3, namely the driving voltage UgS3 of S3 does not meet the driving voltage threshold value (corresponding to the first voltage threshold) of S3, and S3 disconnects; The driving voltage UgS4 of S4 does not meet the driving voltage threshold value (corresponding to the second voltage threshold) of S4 yet, and S4 disconnects.

Circuit state between above-mentioned t3 to t4 can be referred to as mode three.

From the 4th moment t4, until the 5th moment t5, this first control signal is used for, control this first K switch 1 to disconnect, and this second control signal is used for, controls this second switch K2 and close, and the 3rd control signal is used for, control the 3rd K switch 3 to disconnect, and the 4th control signal is used for, controls the 4th K switch 4 and disconnect;

Particularly, between t4 to t5, PWM1 is low level, and PWM2 is high level, and Q1 disconnects, and Q2 closes, and the first end 111 of the first branch road 110 directly connects Vcc-, and the positive charge current i C1 of C1 constantly reduces; Voltage difference between the first end 111 of the first branch road 110 and the second end 112 is less than the driving voltage threshold value (corresponding to the first voltage threshold) of S1, namely the driving voltage Ugs1 of S1 does not meet the driving voltage threshold value (corresponding to the first voltage threshold) of S1, and S1 disconnects; The driving voltage Ugs2 of S2 does not meet the driving voltage threshold value (corresponding to the second voltage threshold) of S2 yet, and S2 disconnects.

Between this t4 to t5, PWM3 is low level, and PWM4 is low level, and Q3 disconnects, and Q4 disconnects, and the first end 131 of the 3rd branch road 130 connects Vcc+ by the drain source capacitance Cds3 of Q3, connects Vcc-by the drain source capacitance Cds4 of Q4.Vcc+ is charged to the drain source capacitance Cds4 of Q4 by the drain source capacitance Cds3 of Q3, and the voltage difference between the first end 131 of the 3rd branch road 130 and the second end 132 constantly raises, the charging current iC3 bottom out of C3.Namely the grid source electric capacity Cgs3 of S3 starts to charge (comprising C3 to charge to Cgs3) always, and the driving voltage Ugs3 of S3 increases gradually, and the drive current ig3 of S3 is just; Second transformer T2 exciting curent increases gradually, and namely the grid source electric capacity Cgs4 of S4 starts charging (comprising C4 always to Cgs4 charging), and the driving voltage Ugs4 of S4 increases gradually, and the drive current ig4 of S4 is just.This process can be referred to as S3 and S4 from being disconnected to closed process.

Circuit state between above-mentioned t4 to t5 can be referred to as mode four.

From the 5th moment t5, until the 6th moment t6, this first control signal is used for, control this first K switch 1 to disconnect, and this second control signal is used for, controls this second switch K2 and close, and the 3rd control signal is used for, control the 3rd K switch 3 to close, and the 4th control signal is used for, and controls the 4th K switch 4 and disconnects;

Particularly, between this t5 to t6 moment, PWM1 is low level, and PWM2 is high level, and Q1 disconnects, and Q2 closes, and the first end 111 of the first branch road 110 directly connects Vcc-, and the positive charge current i C1 of C1 constantly reduces; Voltage difference between the first end 111 of the first branch road 110 and the second end 112 is less than the driving voltage threshold value (corresponding to the first voltage threshold) of S1, namely the driving voltage Ugs1 of S1 does not meet the driving voltage threshold value (corresponding to the first voltage threshold) of S1, and S1 disconnects; The driving voltage Ugs2 of S2 does not meet the driving voltage threshold value (corresponding to the second voltage threshold) of S2 yet, and S2 disconnects.

Between this t5 to t6 moment, PWM3 is high level, and PWM4 is low level, and Q3 closes, and Q4 disconnects, and the first end 131 of the 3rd branch road 130 directly connects Vcc+, and the charging current iC3 of C3 constantly increases; Voltage difference between the first end 131 of the 3rd branch road 130 and the second end 132 meets the driving voltage threshold value (corresponding to tertiary voltage threshold value) of S3, namely the driving voltage Ugs3 of S3 meets its driving voltage threshold value (such as 0.4v-0.7v), S3 conducting.Meanwhile, the second transformer T2 excitation, the 2Ah end of the second secondary is high potential, and 2Al is electronegative potential, and namely the driving voltage Ugs4 of S4 meets its driving voltage threshold value (such as 0.4v-0.7v), S4 conducting, i.e. the equal conducting of S3 and S4.

Circuit state between above-mentioned t5 to t6 can be referred to as mode five.

From the 6th moment t6, until the 7th moment t7, this first control signal is used for, control this first K switch 1 to disconnect, and this second control signal is used for, controls this second switch K2 and close, and the 3rd control signal is used for, control the 3rd K switch 3 to disconnect, and the 4th control signal is used for, controls the 4th K switch 4 and disconnect;

Particularly, between this t6 to t7 moment, PWM1 is low level, and PWM2 is high level, and Q1 disconnects, and Q2 closes, and the first end 111 of the first branch road 110 directly connects Vcc-, and the positive charge current i C1 of C1 constantly reduces; Voltage difference between the first end 111 of the first branch road 110 and the second end 112 is lower than the driving voltage threshold value (corresponding to the first voltage threshold) of S1, namely the driving voltage Ugs1 of S1 is lower than its driving voltage threshold value, S1 disconnects, the driving voltage Ugs2 of S2 is also lower than its driving voltage threshold value, and S2 disconnects.

Between this t6 to t7 moment, PWM3 is low level, and PWM4 is low level, and Q3 disconnects, and Q4 disconnects, and the first end 131 of the 3rd branch road 130 connects Vcc+ by the drain source capacitance Cds3 of Q3, connects Vcc-by the drain source capacitance Cds4 of Q4.The drain source capacitance Cds3 of Q3 charges, and the drain source capacitance Cds4 of Q4 discharges, and particularly, Cds4 charges to C3, and the voltage difference between the first end 131 of the 3rd branch road 130 and the second end 132 constantly reduces, and the charging current iC3 of C3 starts to reduce.The grid source electric capacity Cgs3 of S3 always by energy transferring to the grid source capacitance Cgs4 of C3, S4 always by energy transferring to the driving voltage of C4, S3 and S4, namely Ugs3 and Ugs4 declines gradually, and the drive current of S3 and S4, namely ig3 and ig4 is negative value.This process be S3 and S4 from being closed into the process disconnected completely.

Circuit state between above-mentioned t6 to t7 can be referred to as mode six.

From the 7th moment t7, until the 8th moment t8, this first control signal is used for, control this first K switch 1 to disconnect, and this second control signal is used for, controls this second switch K2 and close, and the 3rd control signal is used for, control the 3rd K switch 3 to disconnect, and the 4th control signal is used for, controls the 4th K switch 4 and close;

Particularly, between this t7 to t8, PWM1 is low level, and PWM2 is high level, and Q1 disconnects, and Q2 closes, and the first end 111 of the first branch road 110 directly connects Vcc-, and the positive charge current i C1 of C1 constantly reduces; Voltage difference between the first end 111 of the first branch road 110 and the second end 112 is lower than the driving voltage threshold value (corresponding to the first voltage threshold) of S1, namely the driving voltage Ugs1 of S1 is lower than its driving voltage threshold value, S1 disconnects, the driving voltage Ugs2 of S2 is also lower than its driving voltage threshold value, and S2 disconnects.

Between this t7 to t8, PWM3 is low level, and PWM4 is high level, and Q3 disconnects, and Q4 closes, and the first end 131 of the 3rd branch road 130 directly connects Vcc-, and the charging current iC3 of C3 constantly reduces, until oppositely increase.Voltage difference between the first end 131 of the 3rd branch road 130 and the second end 132 is less than the driving voltage threshold value (corresponding to tertiary voltage threshold value) of S3, namely the driving voltage UgS3 of S3 does not meet the driving voltage threshold value (corresponding to the first voltage threshold) of S3, and S3 disconnects; The driving voltage UgS4 of S4 does not meet the driving voltage threshold value (corresponding to the second voltage threshold) of S4 yet, and S4 disconnects.

Circuit state between above-mentioned t7 to t8 can be referred to as mode seven.

From the 8th moment t8, until the 9th moment t9, this first control signal is used for, and control this first K switch 1 and disconnect, and this second control signal is used for, control this second switch K2 to disconnect, and the 3rd control signal is used for, control the 3rd K switch 3 and disconnect, and the 4th control signal is used for, control the 4th K switch 4 to close

Particularly, between this t8 to t9, PWM1 is low level, and PWM2 is low level, and Q1 disconnects, and Q2 disconnects, and the first end 111 of the first branch road 110 connects Vcc+ by the drain source capacitance Cds1 of Q1, connects Vcc-by the drain source capacitance Cds2 of Q2.Vcc+ is charged to the drain source capacitance Cds2 of Q2 by the drain source capacitance Cds1 of Q1, thus the voltage difference between the first end 111 of the first branch road 110 and the second end 112 rises gradually, the charging current iC1 bottom out of C1.The grid source electric capacity Cgs1 of S1 starts to charge (comprising C1 to charge to Cgs1) always, and the driving voltage Ugs1 of S1 increases gradually, and the drive current ig1 of S1 is just; Second transformer T2 exciting curent increases gradually, and namely the grid source electric capacity Cgs2 of S2 starts charging (comprising C2 always to Cgs2 charging), and the driving voltage Ugs2 of S2 increases gradually, the drive current ig2 of S2 is just.This process can be referred to as S1 and S2 from being disconnected to closed process.

Between this t8 to t9, PWM3 is low level, and PWM4 is high level, and Q3 disconnects, and Q4 closes, and the first end 131 of the 3rd branch road 130 directly connects Vcc-, and the charging current iC3 of C3 constantly reduces, until oppositely increase.Voltage difference between the first end 131 of the 3rd branch road 130 and the second end 132 is less than the driving voltage threshold value (corresponding to tertiary voltage threshold value) of S3, namely the driving voltage UgS3 of S3 does not meet the driving voltage threshold value (corresponding to the first voltage threshold) of S3, and S3 disconnects; The driving voltage UgS4 of S4 does not meet the driving voltage threshold value (corresponding to the second voltage threshold) of S4 yet, and S4 disconnects.

Circuit state between above-mentioned t8 to t9 can be referred to as mode eight.

Wherein, each moment above-mentioned is different.

Eight mode between t1 to t9 described in above-mentioned composition graphs 6 are a work period.Can be circulated above-mentioned eight mode from the t9 moment, and the embodiment of the present invention is not construed as limiting this, and as shown in Figure 6, the logic state from t9 to the tenth moment t10 is identical with the logic state from t1 to t2.Particularly, the logic state of the tenth moment t10 is identical with the logic state of the second moment t2.

Composition graphs 6 is known, the drive circuit 200 provided according to the embodiment of the present invention shown in Fig. 5, identical logic state can be adopted to drive S1 and S2, adopt identical logic state to drive S3 and S4, and adopt complementary logic state to drive S1 (S2) and S3 (S4).

Under the scene of the control signal inputted respectively at E1, E2, E3 and E4 for PWM1, PWM2, PWM3 and the PWM4 shown in Fig. 6, S1 (S2) and S3 (S4) presents complementary logic state.Should be understood that in actual applications, can according to real needs, the pwm control signal of control E1, E2, E3 and E4 input neatly, thus to realize S1 and S2, logical sequence arbitrary with S3 and S4, the embodiment of the present invention is not construed as limiting this.

Should be understood that the example shown in Fig. 5 and Fig. 6 is to help those skilled in the art to understand the embodiment of the present invention better, and the scope of the embodiment of the present invention have to be limited.Those skilled in the art, according to the example of given Fig. 5 and Fig. 6, obviously can carry out amendment or the change of various equivalence, and such amendment or change also fall in the scope of the embodiment of the present invention.Drive circuit 200 shown in Fig. 5 comprises 2 drive circuit elementary cells (as shown in mark in Fig. 5), alternatively, in embodiments of the present invention, the number increasing drive circuit elementary cell can also be continued, by jointly controlling the closed and disconnection of auxiliary switch device in different driving circuit elementary cell, realize adopting other different logic state to drive multiple main switching device.

As shown in Figure 7, alternatively, this drive circuit 200 provided according to the embodiment of the present invention as shown in Figure 5 also comprises:

For driving the 5th branch road 150 of the 5th main switching device S5,5th branch road 150 comprises the 3rd secondary (1Bh and 1Bl as shown in Figure 7) of the 5th storage capacitor C5 and this first transformer T1 be connected in series, the first end 151 of the 5th branch road 150 connects the first end (the grid g of metal-oxide-semiconductor S5 as shown in Figure 7) of the 5th main switching device S5, second end 152 of the 5th branch road 150 connects second end (the source electrode s of metal-oxide-semiconductor S5 as shown in Figure 7) of the 5th main switching device S5, wherein, 5th main switching device S5 also comprises the 3rd end (the drain electrode d of metal-oxide-semiconductor S5 as shown in Figure 7), when voltage difference between the first end 151 and the second end 152 of the 5th branch road 150 of the 5th branch road 150 is more than or equal to the 5th voltage threshold, second end of the 5th main switching device S5 and the 3rd end conducting of the 5th main switching device S5,5th voltage threshold instruction is provided for the voltage of conducting between second end of the 5th main switching device S5 and the 3rd end of the 5th main switching device S5, and the 5th voltage threshold is greater than zero,

For driving the 6th branch road 160 of the 6th main switching device S6, 6th branch road 160 comprises the 4th secondary (2Bh as shown in Figure 7 of the 6th storage capacitor C6 and this second transformer T2 be connected in series, 2Bl), the first end 161 of the 6th branch road 160 connects the first end (the grid g of metal-oxide-semiconductor S6 as shown in Figure 7) of the 6th main switching device S6, second end 162 of the 6th branch road connects second end (the source electrode s of metal-oxide-semiconductor S6 as shown in Figure 7) of the 6th main switching device S6, wherein, 6th main switching device S6 also comprises the 3rd end (the drain electrode d of metal-oxide-semiconductor S6 as shown in Figure 7), when voltage difference between the first end and the second end of the 6th branch road of the 6th branch road is more than or equal to the 6th voltage threshold, second end of the 6th main switching device S6 and the 3rd end conducting of the 6th main switching device S6, 6th voltage threshold instruction is provided for the voltage of conducting between second end of the 6th main switching device S6 and the 3rd end of the 6th main switching device S6, 6th voltage threshold is greater than zero,

Wherein, this first main switching device S1 and any one in this second main switching device S2 are the upper pipe of the first brachium pontis in voltage transformation module breaker in middle pipe full-bridge circuit, another in this first main switching device S1 and this second main switching device S2 is the lower pipe of the second brachium pontis in this switching tube full-bridge circuit, 3rd main switching device S3 and any one in the 4th main switching device S4 are the lower pipe of this first brachium pontis, another in 3rd main switching device S3 and the 4th main switching device S4 is the upper pipe of this second brachium pontis, 5th main switching device S5 and the 6th main switching device S6 is the synchronous rectifier in this voltage transformation module.

Should be understood that the first end 1Bh of the 3rd secondary of the first transformer T1 and the first end 1Ph on the first former limit is Same Name of Ends; The first end 2Bh of the 4th secondary of the second transformer T2 and the first end 2Ph on the second former limit is Same Name of Ends.

Should also be understood that the drive circuit 200 shown in Fig. 7 can adopt the logical sequence shown in Fig. 6 to carry out work.

Also understand, the first power Vcc shown in Fig. 7 is the driving power of VTM module breaker in middle pipe, and second source Vcc2 is the power supply of VTM module breaker in middle pipe full-bridge circuit, and Vcc2-and Vcc1-can altogether.

Therefore, according to the drive circuit that the embodiment of the present invention provides, the less auxiliary switch device of quantity is adopted to realize the harmless driving of a fairly large number of main switching device, the isolation drive of main switching device can be realized simultaneously, circuit cost is low, and circuit efficiency is high, and has wider range of application, such as can be applied in the module for voltage transitions, such as, in Switching Power Supply.

Circuit logic sequential chart shown in composition graphs 3 is known, the drive circuit that the embodiment of the present invention provides can adopt the multiple main switching device of the harmless driving of same logic state, circuit logic sequential chart shown in composition graphs 6 is known, and the drive circuit that the embodiment of the present invention provides also can adopt the multiple switching device of the harmless driving of multiple logic state.Drive circuit such as shown in Fig. 1 and Fig. 2, can adopt the harmless driving of logic state S1 and S2 as shown in Figure 3; Drive circuit shown in Fig. 4, can adopt logic state harmless driving S1, S2 and S5 as shown in Figure 3; Drive circuit as shown in Figure 5, logic state as shown in Figure 6 can be adopted to drive S1, S2, S3 and S4, the logic state wherein adopting identical logic state can't harm to drive S1 with S2, employing identical is harmless drives S3 and S4, adopts complementary logic state to drive S1 and S3.

Regard the drive circuit 100 shown in Fig. 1 or Fig. 2 as a drive circuit elementary cell, a drive circuit elementary cell can independently realize a kind of logic state, when adopting this drive circuit elementary cell multiple, the harmless driving of the logic state of combination in any can be realized, drive circuit 200 such as shown in Fig. 5 comprises two drive circuit elementary cells, can realize employing two kinds of logic states and can't harm driving two main switching devices.Namely the drive circuit that provides of the embodiment of the present invention, has circuit structure flexibly, can realize the harmless driving of multiple arbitrary logic state flexibly, make drive circuit have wide range of application.

Therefore, the drive circuit for driving switch device that the embodiment of the present invention provides, the harmless driving of multiple logic state can be realized flexibly, and same logic state can the multiple main switching device of isolation drive, simultaneously, the auxiliary switch number of devices adopted is less, the i.e. drive circuit that provides of the embodiment of the present invention, circuit efficiency is higher, circuit cost is lower, the circuit connecting mode of the main switching device driven strictly is not limited, there is wide range of application, thus the universality of harmless Driving technique can be improved.

As shown in Figure 8, the embodiment of the present invention additionally provides a kind of control circuit 300, and this control circuit 300 comprises controller 310 and drive circuit 320, the drive circuit 100 that this drive circuit 320 provides for the embodiment of the present invention or drive circuit 200, this controller 310 for

From the first moment t1, until the second moment t2, this first K switch 1 controlled in this drive circuit closes, and this second switch K2 controlled in this drive circuit disconnects, and drives this first main switching device S1 and the equal conducting of this second main switching device S2 to make this drive circuit;

From this second moment t2, until the 3rd moment t3, controlling this first K switch 1 and disconnect, and control this second switch K2 and disconnect, driving this first main switching device S1 and this second main switching device S2 from being closed into disconnection to make this drive circuit;

From the 3rd moment t3, until the 4th moment t4, control this first K switch 1 and disconnect, and it is closed to control this second switch K2, drive this first main switching device S1 and this second main switching device S2 all to disconnect to make this drive circuit;

From the 4th moment t4, until the 5th moment t5, control this first K switch 1 and disconnect, and control this second switch K2 and disconnect, to make this drive circuit drive this first main switching device S1 and this second main switching device S2 closed from being disconnected to,

Wherein, each moment above-mentioned is different.

Detailed process, as the description of above-mentioned composition graphs 3, for simplicity, does not repeat them here.

The control circuit 300 that the embodiment of the present invention provides, the isolation drive of the first main switching device and the second main switching device can be realized, must common source or altogether without the need to limiting the first main switching device and the second main switching device, effectively improve the range of application of control circuit.

As shown in Figure 9, the embodiment of the present invention additionally provides a kind of control circuit 400, and this control circuit 400 comprises controller 410 and drive circuit 420, the drive circuit 200 that this drive circuit 420 provides for the embodiment of the present invention, this controller 410 for,

From the first moment t1, until the second moment t2, this first K switch 1 controlled in this drive circuit closes, and this second switch K2 controlled in this drive circuit disconnects, and the 3rd K switch 3 controlled in this drive circuit disconnects, and the 4th K switch 4 controlled in this drive circuit closes, to make this drive circuit drive this first main switching device S1 and this second main switching device S2 to close, the 3rd main switching device S3 and the 4th main switching device S4 is driven to disconnect;

From this second moment t2, until the 3rd moment t3, control this first K switch 1 to disconnect, and control this second switch K2 and disconnect, and control the 3rd K switch 3 and disconnect, and it is closed to control the 4th K switch 4, drives this first main switching device S1, this second main switching device S2, the 3rd main switching device S3 and the 4th main switching device S4 all to disconnect to make this drive circuit;

From the 3rd moment t3, until the 4th moment t4, control this first K switch 1 to disconnect, and it is closed to control this second switch K2, and control the 3rd K switch 3 and disconnect, and it is closed to control the 4th K switch 4, drives this first main switching device S1, this second main switching device S2, the 3rd main switching device S3 and the 4th main switching device S4 all to disconnect to make this drive circuit;

From the 4th moment t4, until the 5th moment t5, control this first K switch 1 to disconnect, and it is closed to control this second switch K2, and control the 3rd K switch 3 and disconnect, and control the 4th K switch 4 and disconnect, to make this drive circuit drive this first main switching device S1 and this second main switching device S2 to disconnect, drive the 3rd main switching device S3 and the 4th main switching device S4 closed from being disconnected to;

From the 5th moment t5, until the 6th moment t6, control this first K switch 1 to disconnect, and it is closed to control this second switch K2, and it is closed to control the 3rd K switch 3, and control the 4th K switch 4 and disconnect, to make this drive circuit drive this first main switching device S1 and this second main switching device S2 to disconnect, drive the 3rd main switching device S3 and the 4th main switching device S4 closed;

From the 6th moment t6, until the 7th moment t7, control this first K switch 1 to disconnect, and it is closed to control this second switch K2, and control the 3rd K switch 3 and disconnect, and control the 4th K switch 4 and disconnect, to make this drive circuit drive this first main switching device S1 and this second main switching device S2 to disconnect, drive the 3rd main switching device S3 and the 4th main switching device S4 from being closed into disconnection;

From the 7th moment t7, until the 8th moment t8, control this first K switch 1 to disconnect, and it is closed to control this second switch K2, and control the 3rd K switch 3 and disconnect, and it is closed to control the 4th K switch 4, drives this first main switching device S1, this second main switching device S2, the 3rd main switching device S3 and the 4th main switching device S4 all to disconnect to make this drive circuit;

From the 8th moment t8, until the 9th moment t9, control this first K switch 1 to disconnect, and control this second switch K2 and disconnect, and control the 3rd K switch 3 and disconnect, and control the 4th K switch 4 and close, drive this first main switching device S1 and this second main switching device S2 closed from being disconnected to make this drive circuit, the 3rd main switching device S3 and the 4th main switching device S4 is driven to disconnect

Wherein, each moment above-mentioned is different.

The control circuit 400 that the embodiment of the present invention provides, achieve the isolation drive of multiple switching device, must common source or altogether without the need to limiting the plurality of switching device, and two kinds of complementary logic states can be adopted to can't harm driving four main switching devices, effectively improve the range of application of control circuit.

Should understand, the drive circuit for driving switch device provided according to the embodiment of the present invention and control circuit can be applied to any occasion utilizing switching device, such as, and the drive circuit of voltage transformation module VTM, more specifically, in the drive circuit of Switching Power Supply.

Alternatively, the embodiment of the present invention also provides a kind of device 500 for voltage transitions, as shown in Figure 10, this device 500 comprises voltage-type switching device 510 and control circuit 520, the control circuit 300 that this control circuit 520 provides for the embodiment of the present invention or control circuit 400, this control circuit 520 is for controlling the closed of this voltage-type switching device and disconnecting.

Particularly, this voltage-type switching device 510 is N-channel MOS pipe.This device 500 particularly, can be that Switching Power Supply etc. utilizes voltage-type switching device to realize the equipment of voltage transitions, such as, and existing VTM module.

Should understand, relate to herein first, second, third, fourth, fifth and sixth and the differentiation only carried out for convenience of description of various numeral number (first end 111 of such as the first branch road 110 and the second end 112), be not used for limiting the scope of the embodiment of the present invention.

The negative pole (such as Vcc-) of the power supply related in the above-described embodiments is set to earth potential (ground connection), certainly in specific implementation can be other current potentials as negative potential, the present embodiment is not restricted this.

Should be understood that term "and/or" herein, being only a kind of incidence relation describing affiliated partner, can there are three kinds of relations in expression, and such as, A and/or B, can represent: individualism A, exists A and B simultaneously, these three kinds of situations of individualism B.In addition, character "/" herein, general expression forward-backward correlation is to the relation liking a kind of "or".

Should understand, in various embodiments of the present invention, the size of the sequence number of above-mentioned each process does not also mean that the priority of execution sequence, and the execution sequence of each process should be determined with its function and internal logic, and should not form any restriction to the implementation process of the embodiment of the present invention.

Those of ordinary skill in the art can recognize, in conjunction with unit and the algorithm steps of each example of embodiment disclosed herein description, can realize with the combination of electronic hardware or computer software and electronic hardware.These functions perform with hardware or software mode actually, depend on application-specific and the design constraint of technical scheme.Professional and technical personnel can use distinct methods to realize described function to each specifically should being used for, but this realization should not thought and exceeds scope of the present invention.

Those skilled in the art can be well understood to, and for convenience and simplicity of description, the specific works process of the system of foregoing description, device and unit, with reference to the corresponding process in preceding method embodiment, can not repeat them here.

In several embodiments that the application provides, should be understood that disclosed system, apparatus and method can realize by another way.Such as, device embodiment described above is only schematic, such as, the division of described unit, be only a kind of logic function to divide, actual can have other dividing mode when realizing, such as multiple unit or assembly can in conjunction with or another system can be integrated into, or some features can be ignored, or do not perform.Another point, shown or discussed coupling each other or direct-coupling or communication connection can be by some interfaces, and the indirect coupling of device or unit or communication connection can be electrical, machinery or other form.

The described unit illustrated as separating component or can may not be and physically separates, and the parts as unit display can be or may not be physical location, namely can be positioned at a place, or also can be distributed in multiple network element.Some or all of unit wherein can be selected according to the actual needs to realize the object of the present embodiment scheme.

In addition, each functional unit in each embodiment of the present invention can be integrated in a processing unit, also can be that the independent physics of unit exists, also can two or more unit in a unit integrated.

If described function using the form of SFU software functional unit realize and as independently production marketing or use time, can be stored in a computer read/write memory medium.Based on such understanding, the part of the part that technical scheme of the present invention contributes to prior art in essence in other words or this technical scheme can embody with the form of software product, this computer software product is stored in a storage medium, comprising some instructions in order to make a computer equipment (can be personal computer, server, or the network equipment etc.) perform all or part of step of method described in each embodiment of the present invention.And aforesaid storage medium comprises: USB flash disk, portable hard drive, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disc or CD etc. various can be program code stored medium.

The above; be only the specific embodiment of the present invention, but protection scope of the present invention is not limited thereto, is anyly familiar with those skilled in the art in the technical scope that the present invention discloses; change can be expected easily or replace, all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection range of described claim.

Claims

1. for a drive circuit for driving switch device, it is characterized in that, comprising:

For driving the first branch road of the first main switching device, described first branch road comprises the first former limit of the first storage capacitor and the first transformer be connected in series, the first end of described first branch road connects the first end of described first main switching device, second end of described first branch road connects the second end of described first main switching device, second end of described first branch road also connects the negative pole of power supply, described first main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of described first branch road of described first branch road is more than or equal to the first voltage threshold, second end of described first main switching device and the 3rd end conducting of described first main switching device, described first voltage threshold instruction is provided for the voltage of conducting between the second end of described first main switching device and the 3rd end of described first main switching device, and described first voltage threshold is greater than zero,

First auxiliary switch device, the first end of described first auxiliary switch device connects the first end of described first branch road, second end of described first auxiliary switch device connects the positive pole of described power supply, described first auxiliary switch device comprises the first switch in parallel and the first parasitic capacitance, wherein, when described first switch is closed, the first end of described first branch road is connected with the positive pole of described power supply by closed described first switch, when described first switch disconnects, the first end of described first branch road is connected with the positive pole of described power supply by described first parasitic capacitance,

Second auxiliary switch device, the first end of described second auxiliary switch device connects the first end of described first branch road, second end of described second auxiliary switch device connects the negative pole of described power supply, described second auxiliary switch device comprises second switch in parallel and the second parasitic capacitance, wherein, when described second switch is closed, the first end of described first branch road is connected with the negative pole of described power supply by closed described second switch, when described second switch disconnects, the first end of described first branch road is connected with the negative pole of described power supply by described second parasitic capacitance,

For driving the second branch road of the second main switching device, described second branch road comprises the first secondary of the second storage capacitor and described first transformer be connected in series, the first end of described second branch road connects the first end of described second main switching device, second end of described second branch road connects the second end of described second main switching device, wherein, described second main switching device also comprises the 3rd end, when voltage difference between the first end and the second end of described second branch road of described second branch road is more than or equal to the second voltage threshold, second end of described second main switching device and the 3rd end conducting of described second main switching device, described second voltage threshold instruction is provided for the voltage of conducting between the second end of described second main switching device and the 3rd end of described second main switching device, and described second voltage threshold is greater than zero.

2. drive circuit according to claim 1, is characterized in that, described drive circuit also comprises:

Act on the first control signal input of described first auxiliary switch device, the first control signal of described first control signal input input is used for, and controls the closed of described first switch and disconnects;

Act on the second control signal input of described second auxiliary switch device, the second control signal of described second control signal input input is used for, and controls the closed of described second switch and disconnects.

3. drive circuit according to claim 2, is characterized in that,

From the first moment, until the second moment, described first control signal specifically for, control described first switch close, and described second control signal specifically for, control described second switch disconnect;

From described second moment, until the 3rd moment, described first control signal specifically for, control described first switch disconnect, and described second control signal specifically for, control described second switch disconnect;

From described 3rd moment, until the 4th moment, described first control signal specifically for, control described first switch disconnect, and described second control signal specifically for, control described second switch close;

From described 4th moment, until the 5th moment, described first control signal specifically for, control described first switch disconnect, and described second control signal specifically for, control described second switch disconnect,

Wherein, each moment above-mentioned is different.

4. drive circuit according to any one of claim 1 to 3, it is characterized in that, described first main switching device, described second main switching device, described first auxiliary switch device and described second auxiliary switch device are MOS type field effect transistor MOSFET.

5. drive circuit according to claim 1, is characterized in that, described drive circuit also comprises:

For driving the 3rd branch road of the 3rd main switching device, described 3rd branch road comprises the second former limit of the 3rd storage capacitor and the second transformer be connected in series, the first end of described 3rd branch road connects the first end of described 3rd main switching device, second end of described 3rd branch road connects the second end of described 3rd main switching device, second end of described 3rd branch road also connects the negative pole of described power supply, described 3rd main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of described 3rd branch road of described 3rd branch road is more than or equal to tertiary voltage threshold value, second end of described 3rd main switching device and the 3rd end conducting of described 3rd main switching device, described tertiary voltage threshold value instruction is provided for the voltage of conducting between the second end of described 3rd main switching device and the 3rd end of described 3rd main switching device, and described tertiary voltage threshold value is greater than zero,

3rd auxiliary switch device, the first end of described 3rd auxiliary switch device connects the first end of described 3rd branch road, second end of described 3rd auxiliary switch device connects the positive pole of described power supply, described 3rd auxiliary switch device comprises the 3rd switch and trixenie electric capacity in parallel, wherein, when described 3rd switch is closed, the first end of described 3rd branch road is connected with the positive pole of described power supply by closed described 3rd switch, when described 3rd switch disconnects, the first end of described 3rd branch road is connected with the positive pole of described power supply by described trixenie electric capacity,

4th auxiliary switch device, the first end of described 4th auxiliary switch device connects the first end of described 3rd branch road, second end of described 4th auxiliary switch device connects the negative pole of described power supply, described 4th auxiliary switch device comprises the 4th switch in parallel and the 4th parasitic capacitance, wherein, when described 4th switch is closed, the first end of described 3rd branch road is connected with the negative pole of described power supply by closed described 4th switch, when described 4th switch disconnects, the first end of described 3rd branch road is connected with the negative pole of described power supply by described 4th parasitic capacitance,

For driving the 4th branch road of the 4th main switching device, described 4th branch road comprises the second secondary of the 4th storage capacitor and described second transformer be connected in series, the first end of described 4th branch road connects the first end of described 4th main switching device, second end of described 4th branch road connects the second end of described 4th main switching device, wherein, described 4th main switching device also comprises the 3rd end, when voltage difference between the first end and the second end of described 4th branch road of described 4th branch road is more than or equal to the 4th voltage threshold, second end of described 4th main switching device and the 3rd end conducting of described 4th main switching device, described 4th voltage threshold instruction is provided for the voltage of conducting between the second end of described 4th main switching device and the 3rd end of described 4th main switching device, and described 4th voltage threshold is greater than zero.

6. drive circuit according to claim 5, is characterized in that, described 3rd switch does not close with described first switch simultaneously.

7. the drive circuit according to claim 5 or 6, is characterized in that, described drive circuit also comprises:

Act on the second control signal input of described second auxiliary switch device, the second control signal of described second control signal input input is used for, and controls the closed of described second switch and disconnects;

Act on the 3rd control signal input of described 3rd auxiliary switch device, the 3rd control signal of described 3rd control signal input input is used for, and controls the closed of described 3rd switch and disconnects;

Act on the 4th control signal input of described 4th auxiliary switch device, the 4th control signal of described 4th control signal input input is used for, and controls the closed of described 4th switch and disconnects.

8. drive circuit according to claim 7, is characterized in that,

From the first moment, until the second moment, described first control signal is used for, control described first switch to close, and described second control signal is used for, controls described second switch and disconnect, and described 3rd control signal is used for, control described 3rd switch to disconnect, and described 4th control signal is used for, controls described 4th switch and close;

From described second moment, until the 3rd moment, described first control signal is used for, control described first switch to disconnect, and described second control signal is used for, controls described second switch and disconnect, and described 3rd control signal is used for, control described 3rd switch to disconnect, and described 4th control signal is used for, controls described 4th switch and close;

From described 3rd moment, until the 4th moment, described first control signal is used for, control described first switch to disconnect, and described second control signal is used for, controls described second switch and close, and described 3rd control signal is used for, control described 3rd switch to disconnect, and described 4th control signal is used for, controls described 4th switch and close;

From described 4th moment, until the 5th moment, described first control signal is used for, control described first switch to disconnect, and described second control signal is used for, controls described second switch and close, and described 3rd control signal is used for, control described 3rd switch to disconnect, and described 4th control signal is used for, controls described 4th switch and disconnect;

From described 5th moment, until the 6th moment, described first control signal is used for, control described first switch to disconnect, and described second control signal is used for, controls described second switch and close, and described 3rd control signal is used for, control described 3rd switch to close, and described 4th control signal is used for, controls described 4th switch and disconnect;

From described 6th moment, until the 7th moment, described first control signal is used for, control described first switch to disconnect, and described second control signal is used for, controls described second switch and close, and described 3rd control signal is used for, control described 3rd switch to disconnect, and described 4th control signal is used for, controls described 4th switch and disconnect;

From described 7th moment, until the 8th moment, described first control signal is used for, control described first switch to disconnect, and described second control signal is used for, controls described second switch and close, and described 3rd control signal is used for, control described 3rd switch to disconnect, and described 4th control signal is used for, controls described 4th switch and close;

From described 8th moment, until the 9th moment, described first control signal is used for, and control described first switch and disconnect, and described second control signal is used for, control described second switch to disconnect, and described 3rd control signal is used for, control described 3rd switch and disconnect, and described 4th control signal is used for, control described 4th switch to close

Wherein, each moment above-mentioned is different.

9. the drive circuit according to any one of claim 5 to 8, it is characterized in that, described first main switching device, described second main switching device, described 3rd main switching device, described 4th main switching device, described first auxiliary switch device, described second auxiliary switch device, described 3rd auxiliary switch device and described 4th auxiliary switch device are MOS type field effect transistor MOSFET.

10. the drive circuit according to any one of claim 5 to 9, is characterized in that, described drive circuit also comprises:

For driving the 5th branch road of the 5th main switching device, described 5th branch road comprises the 3rd secondary of the 5th storage capacitor and described first transformer be connected in series, the first end of described 5th branch road connects the first end of described 5th main switching device, second end of described 5th branch road connects the second end of described 5th main switching device, described 5th main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of described 5th branch road of described 5th branch road is more than or equal to the 5th voltage threshold, second end of described 5th main switching device and the 3rd end conducting of described 5th main switching device, described 5th voltage threshold instruction is provided for the voltage of conducting between the second end of described 5th main switching device and the 3rd end of described 5th main switching device, described 5th voltage threshold is greater than zero,

For driving the 6th branch road of the 6th main switching device, described 6th branch road comprises the 4th secondary of the 6th storage capacitor and described second transformer be connected in series, the first end of described 6th branch road connects the first end of described 6th main switching device, second end of described 6th branch road connects the second end of described 6th main switching device, described 6th main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of described 6th branch road of described 6th branch road is more than or equal to the 6th voltage threshold, second end of described 6th main switching device and the 3rd end conducting of described 6th main switching device, described 6th voltage threshold instruction is provided for the voltage of conducting between the second end of described 6th main switching device and the 3rd end of described 6th main switching device, described 6th voltage threshold is greater than zero,

Wherein, any one in described first main switching device and described second main switching device is the upper pipe of the first brachium pontis in voltage transformation module breaker in middle pipe full-bridge circuit, another in described first main switching device and described second main switching device is the lower pipe of the second brachium pontis in described switching tube full-bridge circuit, any one in described 3rd main switching device and described 4th main switching device is the lower pipe of described first brachium pontis, another in described 3rd main switching device and described 4th main switching device is the upper pipe of described second brachium pontis, described 5th main switching device and the 6th main switching device are the synchronous rectifier in described voltage transformation module.

11. drive circuits according to any one of claim 1 to 9, is characterized in that, described drive circuit also comprises:

For driving the 5th branch road of the 5th main switching device, described 5th branch road comprises the 3rd secondary of the 5th storage capacitor and described first transformer be connected in series, the first end of described 5th branch road connects the first end of described 5th main switching device, second end of described 5th branch road connects the second end of described 5th main switching device, described 5th main switching device also comprises the 3rd end, wherein, when voltage difference between the first end and the second end of described 5th branch road of described 5th branch road is more than or equal to the 5th voltage threshold, second end of described 5th main switching device and the 3rd end conducting of described 5th main switching device, described 5th voltage threshold instruction is provided for the voltage of conducting between the second end of described 5th main switching device and the 3rd end of described 5th main switching device, described 5th voltage threshold is greater than zero.

12. 1 kinds of control circuits, comprise controller and the drive circuit according to any one of claim 1 to 11, it is characterized in that:

From the first moment, until the second moment,

Described controller is used for, described first switch controlled in the described drive circuit in described drive circuit closes, and the described second switch controlled in described drive circuit disconnects, drive described first main switching device and the equal conducting of described second main switching device to make described drive circuit;

From described second moment, until the 3rd moment,

Described controller disconnects for controlling described first switch, and controls the disconnection of described second switch, drives described first main switching device and described second main switching device from being closed into disconnection to make described drive circuit;

From described 3rd moment, until the 4th moment,

Described controller disconnects for controlling described first switch, and it is closed to control described second switch, drives described first main switching device and described second main switching device all to disconnect to make described drive circuit;

From described 4th moment, until the 5th moment,

Described controller for control described first switch disconnect, and control described second switch disconnect, with make described drive circuit drive described first main switching device and described second main switching device closed from being disconnected to,

Wherein, each moment above-mentioned is different.

13. 1 kinds of control circuits, comprise controller and the drive circuit according to any one of claim 5 to 10, it is characterized in that:

From the first moment, until the second moment,

Described controller closes for described first switch controlled in described drive circuit, and the described second switch controlled in described drive circuit disconnects, and described 3rd switch controlled in described drive circuit disconnects, and described 4th switch controlled in described drive circuit closes, to make described drive circuit drive described first main switching device and described second main switching device to close, described 3rd main switching device and described 4th main switching device is driven to disconnect;

From described second moment, until the 3rd moment,

Described controller disconnects for controlling described first switch, and control the disconnection of described second switch, and control described 3rd switch disconnection, and it is closed to control described 4th switch, described first main switching device, described second main switching device, described 3rd main switching device and described 4th main switching device is driven all to disconnect to make described drive circuit;

From described 3rd moment, until the 4th moment,

Described controller disconnects for controlling described first switch, and it is closed to control described second switch, and control described 3rd switch disconnection, and it is closed to control described 4th switch, described first main switching device, described second main switching device, described 3rd main switching device and described 4th main switching device is driven all to disconnect to make described drive circuit;

From described 4th moment, until the 5th moment,

Described controller disconnects for controlling described first switch, and it is closed to control described second switch, and control described 3rd switch disconnection, and control described 4th switch disconnection, with make described drive circuit drive described first main switching device and described second main switching device disconnect, drive described 3rd main switching device and described 4th main switching device closed from being disconnected to;

From described 5th moment, until the 6th moment,

Described controller disconnects for controlling described first switch, and it is closed to control described second switch, and it is closed to control described 3rd switch, and control described 4th switch disconnection, to make described drive circuit drive described first main switching device and described second main switching device to disconnect, described 3rd main switching device and described 4th main switching device is driven to close;

From described 6th moment, until the 7th moment,

Described controller disconnects for controlling described first switch, and it is closed to control described second switch, and control described 3rd switch disconnection, and control described 4th switch disconnection, to make described drive circuit drive described first main switching device and described second main switching device to disconnect, drive described 3rd main switching device and described 4th main switching device from being closed into disconnection;

From described 7th moment, until the 8th moment,

From described 8th moment, until the 9th moment,

Described controller disconnects for controlling described first switch, and control the disconnection of described second switch, and control described 3rd switch disconnection, and it is closed to control described 4th switch, with make described drive circuit drive described first main switching device and described second main switching device closed from being disconnected to, described 3rd main switching device and described 4th main switching device is driven to disconnect

Wherein, each moment above-mentioned is different.

14. 1 kinds for the device of voltage transitions, is characterized in that, comprising:

Voltage-type switching device and the control circuit as described in claim 12 or 13, described control circuit is for controlling the closed of described voltage-type switching device and disconnecting.