阅读说明：本技术 电源转换器 (Power converter ) 是由 庄陈英 于 2021-10-20 设计创作，主要内容包括：本申请涉及一种电源转换器,包括开关电路以及控制电路；开关电路连接在电能传输通道上；电能传输通道为电源转换器在输出电能时的电流从电源输入端到电源输出端流经的电路；在需要电源转换器停止输出电能时,电能传输通道断开,控制电路控制开关电路断开,以切断电能传输通道上的同步MOS管的寄生二极管的导通,从而实现不需要给与电源转换器连接用电器件供电时,同时切断电能传输通道和电能传输通道上的同步MOS管的寄生二极管,达到真实关断,避免传统技术中无法真实关断,而造成的电能浪费和损害器件的问题。(The application relates to a power converter, comprising a switch circuit and a control circuit; the switch circuit is connected to the electric energy transmission channel; the electric energy transmission channel is a circuit through which current flows from the power input end to the power output end when the power converter outputs electric energy; when the power converter is required to stop outputting electric energy, the electric energy transmission channel is disconnected, the control circuit controls the switching circuit to be disconnected so as to cut off the conduction of the parasitic diode of the synchronous MOS tube on the electric energy transmission channel, so that when the power converter is not required to be connected with an electric device for power supply, the parasitic diodes of the synchronous MOS tube on the electric energy transmission channel and the electric energy transmission channel are cut off simultaneously, real cut-off is achieved, and the problems that electric energy is wasted and the device is damaged due to the fact that the conventional technology cannot be really cut off are solved.)

1. A power converter is characterized by comprising a switching circuit and a control circuit;

the switch circuit is connected to the electric energy transmission channel; the electric energy transmission channel is a circuit through which current flows from a power supply input end to a power supply output end when the power supply converter outputs electric energy;

when the power converter is required to stop outputting the electric energy, the electric energy transmission channel is disconnected, and the control circuit controls the switching circuit to be disconnected so as to cut off the conduction of the parasitic diode of the synchronous MOS tube on the electric energy transmission channel.

2. The power converter of claim 1, wherein the switching circuit comprises a switching MOS transistor;

the source electrode and the substrate of the switch MOS tube are both connected with the substrate of the synchronous MOS tube, the drain electrode is connected with the drain electrode of the synchronous MOS tube, and the grid electrode is connected with the control circuit;

and the parasitic diode of the synchronous MOS tube is parasitic between the source electrode of the synchronous MOS tube and the source electrode of the switch MOS tube.

3. The power converter according to claim 2, wherein the switching MOS transistor is a P-type MOS transistor;

the control circuit inputs a high level signal to the switch MOS tube to control the switch MOS tube to be disconnected.

4. The power converter according to claim 2, wherein the switching MOS transistor is an N-type MOS transistor;

the control circuit inputs a low level signal to the switch MOS tube to control the switch MOS tube to be disconnected.

5. The power converter of claim 1, wherein the switching circuit comprises a switching transistor;

the emitter of the switching triode is connected with the substrate of the synchronous MOS tube, the collector of the switching triode is connected with the drain of the synchronous MOS tube, and the base of the switching triode is connected with the control circuit;

and the parasitic diode of the synchronous MOS tube is parasitic between the source electrode of the synchronous MOS tube and the emitting electrode of the switching triode.

6. The power converter according to claim 5, wherein the switching transistor is a P-type transistor;

the control circuit inputs a high level signal to the switching triode so as to control the switching triode to be disconnected.

7. The power converter according to claim 5, wherein the switching transistor is an N-type transistor;

the control circuit inputs a low level signal to the switching triode so as to control the switching triode to be disconnected.

8. The power converter according to any one of claims 1 to 7, further comprising a PWM control driver;

the PWM control driver is connected with the grid electrode of the synchronous MOS tube; the control circuit is integrated on the PWM control driver.

9. The power converter according to claim 8, further comprising an inductor, a control MOS transistor, and a capacitor;

the PWM control driver is also connected with a grid electrode of the control MOS tube;

one end of the inductor is respectively connected with the source electrode of the synchronous MOS tube and the drain electrode of the control MOS tube, and the other end of the inductor is used as the power input end; the source electrode of the control MOS tube and the substrate are grounded;

and the drain electrode of the synchronous MOS tube is used as the power output end and is grounded through the capacitor.

10. The power converter according to any one of claims 1 to 7, further comprising a PWM control driver, an inductor, a control MOS transistor and a capacitor;

the PWM control driver is respectively connected with the grid electrode of the synchronous MOS tube and the grid electrode of the control MOS tube;

one end of the inductor is respectively connected with the source electrode of the synchronous MOS tube and the drain electrode of the control MOS tube, and the other end of the inductor is used as the power input end; the source electrode of the control MOS tube and the substrate are grounded;

and the drain electrode of the synchronous MOS tube is used as the power output end and is grounded through the capacitor.

Technical Field

The present application relates to the field of power supply technologies, and in particular, to a power converter.

Background

As an important component of an electric device, the performance of a power converter has an important influence on the electric device. A power converter in the conventional technology is composed of an inductor, a capacitor, a Metal-Oxide-Semiconductor Field-Effect Transistor (MOS) Transistor, a synchronous MOS Transistor, and a control circuit.

However, when the power converter of this type is turned off, since the inductor is connected to the parasitic diode of the synchronous MOS transistor, a current exists between the power input terminal and the power output terminal of the power converter, so that the power converter is not substantially turned off, energy loss is caused, and the voltage at the power output terminal cannot return to the initial state of 0 v, and therefore, in the implementation process, the inventor finds that at least the following problems exist in the conventional technology: the conventional boost power converter cannot achieve true turn-off.

Disclosure of Invention

Therefore, it is necessary to provide a power converter for solving the problem that the conventional boost power converter cannot be turned off truly.

In order to achieve the above object, an embodiment of the present application provides a power converter, including a switching circuit and a control circuit;

the switch circuit is connected to the electric energy transmission channel; the electric energy transmission channel is a circuit through which current flows from the power input end to the power output end when the power converter outputs electric energy;

when the power converter is required to stop outputting the electric energy, the electric energy transmission channel is disconnected, and the control circuit controls the switching circuit to be disconnected so as to cut off the conduction of the parasitic diode of the synchronous MOS tube on the electric energy transmission channel.

Optionally, the switching circuit includes a switching MOS transistor;

the source electrode and the substrate of the switch MOS tube are both connected with the substrate of the synchronous MOS tube, the drain electrode is connected with the drain electrode of the synchronous MOS tube, and the grid electrode is connected with the control circuit;

the parasitic diode of the synchronous MOS tube is parasitic between the source electrode of the synchronous MOS tube and the source electrode of the switch MOS tube.

Optionally, the switch MOS transistor is a P-type MOS transistor;

the control circuit inputs a high level signal to the switch MOS tube to control the switch MOS tube to be disconnected.

Optionally, the switch MOS transistor is an N-type MOS transistor;

the control circuit inputs a low level signal to the switch MOS tube to control the switch MOS tube to be disconnected.

Optionally, the switching circuit includes a switching transistor;

the emitter of the switching triode is connected with the substrate of the synchronous MOS tube, the collector of the switching triode is connected with the drain of the synchronous MOS tube, and the base of the switching triode is connected with the control circuit;

the parasitic diode of the synchronous MOS tube is parasitic between the source electrode of the synchronous MOS tube and the emitting electrode of the switching triode.

Optionally, the switching triode is a P-type triode;

the control circuit inputs a high level signal to the switching triode so as to control the switching triode to be disconnected.

Optionally, the switching triode is an N-type triode;

the control circuit inputs a low level signal to the switching triode so as to control the switching triode to be disconnected.

Optionally, the power converter further comprises a PWM control driver;

the PWM control driver is connected with the grid electrode of the synchronous MOS tube; the control circuit is integrated on the PWM control driver.

Optionally, the power converter further includes an inductor, a control MOS transistor, and a capacitor;

the PWM control driver is also connected with a grid of the control MOS tube;

one end of the inductor is respectively connected with the source electrode of the synchronous MOS tube and the drain electrode of the control MOS tube, and the other end of the inductor is used as a power input end; controlling the source electrode of the MOS tube and the substrate to be grounded;

the drain electrode of the synchronous MOS tube is used as a power output end and is grounded through a capacitor.

Optionally, the power converter further includes a PWM control driver, an inductor, a control MOS transistor, and a capacitor;

the PWM control driver is respectively connected with the grid of the synchronous MOS tube and the grid of the control MOS tube;

one end of the inductor is respectively connected with the source electrode of the synchronous MOS tube and the drain electrode of the control MOS tube, and the other end of the inductor is used as a power input end; controlling the source electrode of the MOS tube and the substrate to be grounded;

the drain electrode of the synchronous MOS tube is used as a power output end and is grounded through a capacitor.

One of the above technical solutions has the following advantages and beneficial effects:

the power converter comprises a switch circuit and a control circuit, wherein the switch circuit is arranged on an electric energy transmission channel (the electric energy transmission channel refers to a circuit between a power input end and a power output end of the power converter), when the power converter is required to stop outputting electric energy, the power converter disconnects the electric energy transmission channel, the control circuit controls the switch circuit to be disconnected, so that the conduction of a parasitic diode of a synchronous MOS (metal oxide semiconductor) tube on the electric energy transmission channel is cut off, when the power converter is not required to be connected with an electric device for supplying power, the parasitic diodes of the synchronous MOS tube on the electric energy transmission channel and the electric energy transmission channel are cut off simultaneously, the real cut-off is achieved, the problems that the electric energy cannot be really cut off in the traditional technology and the electric energy is wasted and the device is damaged are avoided.

Drawings

Fig. 1 is a circuit diagram of a boost power converter in the prior art.

Fig. 2 is a switching point waveform diagram of the circuit diagram shown in fig. 1.

Fig. 3 is a schematic structural diagram of a power converter according to an embodiment of the present disclosure.

Fig. 4 is a circuit diagram of a switching circuit of a power converter according to an embodiment of the present disclosure.

Fig. 5 is another circuit diagram of a switching circuit of a power converter provided in this application.

Fig. 6 is a schematic structural diagram of a control circuit of a power converter according to an embodiment of the present disclosure.

Fig. 7 is a control timing diagram of a power converter according to an embodiment of the present disclosure.

Fig. 8 is a current flow diagram of a power converter provided in an implementation of the present application.

Fig. 9 is a structural diagram of a power converter in an off state according to an embodiment of the present disclosure.

The reference numbers illustrate:

3. a power converter; 31. a switching circuit; 32. a control circuit; 33. a power transmission channel; 34. a synchronous MOS tube; 35. a PWM control driver; 36. an inductance; 37. controlling the MOS tube; 38. a capacitor; 311. switching an MOS tube; 313. and switching the triode.

Detailed Description

To facilitate an understanding of the present application, the present application will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present application are shown in the drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element and be integral therewith, or intervening elements may also be present. The terms "mounted," "one end," "the other end," and the like are used herein for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As shown in fig. 1, a boost power converter in the prior art includes an inductor 11, a capacitor 12, a Metal-Oxide-Semiconductor Field-Effect Transistor (MOS) Transistor 13, a parasitic diode 14 of the MOS Transistor 13, a synchronous MOS Transistor 15, a parasitic diode 16 of the synchronous MOS Transistor 15, and a control circuit 17. The control circuit 17 includes PWM (Pulse Width Modulation) and BBW

Referring to FIG. 2, the switching point (V) of the boost power converter shown in FIG. 1 is shown_x) The waveform controls the MOS transistor 13 to be turned on and switched at a point (V) from the time t equals 0 to the time t equals t1 in fig. 2_x) For low impedance grounding, the voltage is determined by the product of the current flowing through the control MOS transistor 13 and its on-resistance. When the MOS transistor to be controlled 13 is turned off and the synchronous MOS transistor 15 is not conducted, the parasitic diode 16 of the synchronous MOS transistor 15 is conducted because the current of the inductor 11 follows the KCL (Kirchoff Current Law) law, and therefore V is_outTerminal voltage is equal to V_out+V_f(shown in FIG. 2 as paragraph 32), where V_fThe parasitic diode 16 of the synchronous MOS transistor 15 is energized across. Thereafter, when the synchronous MOS transistor 15 is turned on, the voltage is as indicated by a segment 33 in fig. 2. When the synchronous MOS transistor 15 is turned off again, the voltage is as followsShown in fig. 2 at section 34. When the energy stored in the inductor 11 is consumed, the voltage decreases at a very fast speed, and the voltage is shown as t-t 1 in fig. 2. In the case of the boosting operation, the components operate according to the command of the control circuit 17 shown in fig. 1 to achieve the purpose of boosting.

However, in the case of the boost power converter being turned off, since the inductor 11 is connected to the parasitic diode 16 of the synchronous MOS transistor 15, the current is inevitably drawn from V in fig. 1_battFlow direction V_outResulting in the boost power converter not being substantially turned off, resulting in V_battEnergy loss of (2). The boost power converter cannot make V under the condition of turn-off_outThe voltage returns to the initial state of 0 volts, so that the boost power converter cannot achieve true shutdown.

In order to solve the above problem, as shown in fig. 3, there is provided a power converter 3 including a switch circuit 31 and a control circuit 32.

In the actual use process, the power output end of the power converter 3 is connected with the electric device, and the power input end of the power converter 3 is connected with the voltage source or the current source. When the power converter 3 supplies power to the consumer via the power output terminal (i.e., outputs power), a current flows from the power input terminal to the power output terminal, and the current flows from the power input terminal (V shown in fig. 3)_batt) To the power supply output (V as shown in FIG. 3)_out) The current flowing through the circuit is the power transmission path of the power converter 3.

The switching circuit 31 is connected to the power transmission path for cutting off the conduction of the parasitic diode of the synchronous MOS transistor 34 in the power transmission path. The parasitic diode of the synchronous MOS transistor 34 is formed by a manufacturing process, and the drain of the MOS transistor is led out from the bottom of the silicon wafer to form the parasitic diode of the synchronous MOS transistor 34. The synchronous MOS transistor 34 serves as a switching element, and receives level signal control to turn off or turn on the power transmission channel. For example, when the synchronous MOS transistor 34 is a P-type MOS transistor, the synchronous MOS transistor 34 is turned off when the level signal is a high level signal, and the synchronous MOS transistor 34 is turned on when the level signal is a low level signal. When the synchronous MOS transistor 34 is an N-type MOS transistor, the synchronous MOS transistor 34 is turned off when the level signal is a low level signal, and the synchronous MOS transistor 34 is turned on when the level signal is a high level signal. Specifically, the level signal is input from the gate of the synchronous MOS transistor 34. To achieve control of the synchronous MOS transistor 34, as shown in fig. 3, in one example, the power converter 3 further includes a PWM control driver 35; the PWM control driver 35 is connected to the gate of the synchronous MOS transistor 34. It is understood that the PWM control driver 35 inputs a level signal to the synchronous MOS transistor 34.

In the process of outputting the electric energy, the electric energy transmission channel is conducted, and the control circuit 32 controls the switch circuit 31 to be conducted so as to conduct the parasitic diode of the synchronous MOS transistor 34 in the electric energy transmission channel. When the power converter 3 is required to stop outputting the power (i.e. the power supply to the consumer device is not required), the power transmission channel is disconnected, and the control circuit 32 controls the switch circuit 31 to be disconnected to cut off the conduction of the parasitic diode of the synchronous MOS transistor 34 in the power transmission channel. The parasitic diode of the synchronous MOS transistor 34 in the power transmission path is connected to the power transmission path by the parasitic diode of the synchronous MOS transistor 34. The disconnection of the parasitic diode of the synchronous MOS transistor 34 in the power transmission path means that the parasitic diode of the synchronous MOS transistor 34 is disconnected from the power transmission path.

The implementation of the switch circuit 31 is not limited, and the switch circuit 31 may be implemented as required by the present application, and two possible ways are provided as follows:

as shown in fig. 4, in one example, the switching circuit 31 includes a switching MOS transistor 311; the source electrode and the substrate of the switch MOS tube 311 are both connected with the substrate of the synchronous MOS tube 34, the drain electrode is connected with the drain electrode of the synchronous MOS tube 34, and the grid electrode is connected with the control circuit 32; the parasitic diode of the synchronous MOS transistor 34 is parasitic between the source of the synchronous MOS transistor 34 and the source of the switching MOS transistor 311.

When the switch MOS 311 is a P-type MOS, the control circuit 32 inputs a high level signal to the switch MOS 311 to control the switch MOS 311 to be turned off, and the control circuit 32 inputs a low level signal to the switch MOS 311 to control the switch MOS 311 to be turned on. When the switch MOS 311 is an N-type MOS, the control circuit 32 inputs a low level signal to the switch MOS 311 to control the switch MOS 311 to be turned off, and the control circuit 32 inputs a high level signal to the switch MOS 311 to control the switch MOS 311 to be turned on.

As shown in fig. 5, in another example, the switching circuit 31 includes a switching transistor 313; an emitting electrode of the switching triode 313 is connected with the substrate of the synchronous MOS tube 34, a collecting electrode is connected with the drain electrode of the synchronous MOS tube 34, and a base electrode is connected with the control circuit 32; the parasitic diode of the synchronous MOS transistor 34 is parasitic between the source of the synchronous MOS transistor 34 and the emitter of the switching transistor 313.

It should be noted that, when the switching transistor 313 is a P-type transistor, the control circuit 32 inputs a high level signal to the switching transistor 313 to control the switching transistor 313 to be turned off, and the control circuit 32 inputs a low level signal to the switching transistor 313 to control the switching transistor 313 to be turned on. When the switching transistor 313 is an N-type transistor, the control circuit 32 inputs a low level signal to the switching transistor 313 to control the switching transistor 313 to be turned off, and the control circuit 32 inputs a high level signal to the switching transistor 313 to control the switching transistor 313 to be turned on.

The control circuit 32 is configured to send a control signal to the switch circuit 31 to control the switch circuit 31 to be turned on or off, for example, the control circuit 32 may be a single chip, a signal generator, or the like. In one example, the control circuit 32 may detect whether the electrical device connected to the power converter 3 needs power, and when the electrical device needs power (i.e., the power converter 3 needs to output power), the control circuit 32 controls the switching circuit 31 to be turned on. When it is detected that the electricity consuming device does not need electricity (i.e. the power converter 3 is required to output power), the control circuit 32 controls the switching circuit 31 to be turned off. In another example, whether or not the consumer connected to the power converter 3 needs to be powered may be detected by an external detection circuit that notifies the control circuit 32 when it detects that the consumer needs to be powered, so that the control circuit 32 controls the switching circuit 31 to be turned on. When the external detection circuit detects that the electric device does not need to use electricity, the external detection circuit notifies the control circuit 32 so that the control circuit 32 controls the switch circuit 31 to be turned off. For example, the external detection circuit may be the PWM control driver 35.

In one example, as shown in fig. 6, the control circuit 32 and the PWM control driver 35 are the same device, that is, the control circuit 32 is integrated on the PWM control driver 35. Specifically, the power converter 3 further includes a PWM control driver 35; the PWM control driver 35 is connected with the grid electrode of the synchronous MOS tube 34; the control circuit 32 is integrated on the PWM control driver 35. It should be noted that, integrating the control circuit 32 into the PWM control driver 35 can save the use of devices and reduce the cost. In this example, when the power supply needs to convert the output power, the PWM control driver 35 controls the synchronous MOS transistor 34 to be turned on to turn on the power transmission channel of the power supply converter 3, and the control circuit 32 controls the switching circuit 31 to be turned on to turn on the parasitic diode of the synchronous MOS transistor 34 of the synchronous MOS transistor, so that the power supply converter 3 supplies power to the electrical device connected thereto. When the power conversion is not needed to output the electric energy, the PWM control driver 35 controls the synchronous MOS transistor 34 to be turned off to disconnect the electric energy transmission channel of the power converter 3, and the control circuit 32 controls the switch circuit 31 to cut off the conduction of the parasitic diode of the synchronous MOS transistor 34 of the synchronous MOS transistor, so that the power converter 3 stops supplying the electric energy to the electrical equipment connected thereto.

In this example, the power converter 3 further includes an inductor 36, a control MOS transistor 37, and a capacitor 38; the PWM control driver 35 is also connected with the grid electrode of the control MOS tube 37; one end of the inductor 36 is connected to the source of the synchronous MOS transistor 34 and the drain of the control MOS transistor 37, respectively, and the other end is used as a power input end; the source electrode of the control MOS tube 37 and the substrate are grounded; the drain of the synchronous MOS transistor 34 serves as a power output terminal and is grounded through a capacitor 38.

It should be noted that the inductor 36 is used to connect a voltage source or a current source as an energy storage device. During the charging process of the inductor 36, the PWM control driver 35 controls the control MOS transistor 37 to be turned on, controls the synchronous MOS transistor 34 to be turned off, and controls the control circuit 32 to control the switching circuit 31 to be turned on, so as to charge the inductor 36. When the power converter 3 is required to output electric energy, the PWM control driver 35 controls the control MOS transistor 37 to be turned off, the synchronous MOS transistor 34 to be turned on, and the control circuit 32 controls the switching circuit 31 to be turned on to output electric energy. When the power converter 3 is not required to output power, the PWM control driver 35 controls the control MOS transistor 37 to be turned off, the synchronous MOS transistor 34 to be turned off, and the control circuit 32 controls the switching circuit 31 to be turned off to stop outputting power.

In another example, as shown in fig. 3, the control circuit 32 and the PWM control driver 35 are independent devices. Specifically, the power converter 3 further includes a PWM control driver 35, an inductor 36, a control MOS transistor 37, and a capacitor 38; the PWM control driver 35 is respectively connected with the grid of the synchronous MOS tube 34 and the grid of the control MOS tube 37; one end of the inductor 36 is connected to the source of the synchronous MOS transistor 34 and the drain of the control MOS transistor 37, respectively, and the other end is used as a power input end; the source electrode of the control MOS tube 37 and the substrate are grounded; the drain of the synchronous MOS transistor 34 serves as a power output terminal and is grounded through a capacitor 38.

The control circuit 32 and the PWM control driver 35 are connected, and the control circuit 32 and the PWM control driver 35 may or may not be connected. When the control circuit 32 and the PWM control driver 35 are connected, it is realized that the PWM control driver 35 detects whether the electric device needs to use the electric power, and the PWM control driver 35 notifies the control circuit 32. When the control circuit 32 and the PWM control driver 35 are not connected, the control circuit 32 needs to autonomously detect whether the electric device needs to be powered or an external detection circuit detects it.

In order to facilitate a better understanding of the working principle of the power converter 3 of the present application, a specific embodiment is described below:

as shown in fig. 4, the power converter 3 includes a switch circuit 31, a control circuit 32, a PWM control driver 35, an inductor 36, a synchronous MOS transistor 34, a control MOS transistor 37, and a capacitor 38. The synchronous MOS transistor 34 is a P-type MOS transistor. The control MOS transistor 37 is an N-type MOS transistor.

The switch circuit 31 includes a switch MOS 311, the control circuit 32 is connected to the gate of the switch MOS 311, and the switch MOS 311 is a P-type MOS.

The PWM control driver 35 is connected to the gate of the synchronous MOS transistor 34 and the gate of the control MOS transistor 37, respectively.

One end of the inductor 36 is connected to the source of the synchronous MOS transistor 34 and the drain of the control MOS transistor 37, respectively, and the other end is used as a power input end, and the source of the control MOS transistor 37 and the substrate are grounded.

The drain of the synchronous MOS transistor 34 serves as a power output terminal and is grounded through a capacitor 38.

The parasitic diode of the synchronous MOS transistor 34 is parasitic between the source of the synchronous MOS transistor 34 and the source of the switching MOS transistor 311.

The inductor 36 and the synchronous MOS transistor 34 between the power input end and the power output end form an electric energy transmission channel of the power converter 3.

The power converter 3 in this example is controlled according to the timing chart shown in fig. 7, and fig. 7 includes a driving signal of the synchronous MOS transistor 34, a driving signal of the control MOS transistor 37, and an enable signal of the switching MOS transistor 311. During the normal charging and discharging process of the power converter 3, the synchronous MOS transistor 34 and the control MOS transistor 37 are controlled by two identical driving signals, and at this time, the enable signal of the switching MOS transistor 311 is a low level signal. Specifically, in the charging process, the driving signals of the synchronous MOS transistor 34 and the control MOS transistor 37 are high level signals, the synchronous MOS transistor 34 is turned off, and the control MOS transistor 37 is turned on. In the discharging process, the driving signals of the synchronous MOS transistor 34 and the control MOS transistor 37 are low level signals, the synchronous MOS transistor 34 is turned on, and the control MOS transistor 37 is turned off. When the power converter 3 needs to be turned off, the driving signal of the synchronous MOS transistor 34 is a high level signal, the driving signal of the control MOS transistor 37 is a low level signal, and the enable signal of the switch MOS transistor 311 is a high level signal, so that the synchronous MOS transistor 34, the control MOS transistor 37, and the switch MOS transistor 311 are turned off, and the power converter 3 stops outputting electric energy to the electrical equipment connected thereto.

Fig. 8 shows the current flow direction of the power converter 3 in this example. During the normal charging and discharging process of the power converter 3, the switching MOS 311 is turned on, the synchronous MOS 34 is switched between on and off according to the corresponding driving signal, and the control MOS 37 is also switched between on and off according to the corresponding driving signal, so that three currents flow through the power converter 3 during this process. Specifically, the first current path: the current flows through the power input end, the inductor 36, the parasitic diode of the synchronous MOS tube 34, the switch MOS tube 311 and the power output end in sequence; a second current path: when the driving signal is high voltage, the synchronous MOS transistor 34 is turned off, the control MOS transistor 37 is turned on, and the current sequentially flows through the power input terminal, the inductor 36, and the control MOS transistor 37; the third current path: when the driving signal is low voltage, the synchronous MOS transistor 34 is turned on, the control MOS transistor 37 is turned off, and the current flows through the power input terminal, the inductor 36, the synchronous MOS transistor 34, and the power output terminal in sequence. The power converter 3 of the present application provides a first current path that is not available in the conventional boost power converter 3 shown in fig. 1.

Shown in fig. 9 is the off mode of the power converter 3 in this example. In the off mode, the driving signal of the synchronous MOS transistor 34 is a high level signal, the driving signal of the control MOS transistor 37 is a low level signal, and the enable signal of the switching MOS transistor 311 is a high level signal, so as to turn off the synchronous MOS transistor 34, the control MOS transistor 37, and the switching MOS transistor 311. After the power converter is switched off, three current paths in the power converter 3 do not exist, and the real switching off is realized.

The power converter 3 of the present application includes a switch circuit 31 and a control circuit 32, wherein the switch circuit 31 is disposed on an electric energy transmission channel (the electric energy transmission channel refers to a circuit between a power input end and a power output end of the power converter 3), when the power converter 3 is required to stop outputting electric energy, the power converter 3 disconnects the electric energy transmission channel, the control circuit 32 controls the switch circuit 31 to disconnect, so as to cut off the conduction of the parasitic diode of the synchronous MOS transistor 34 on the electric energy transmission channel, thereby realizing that when the electric device for connecting with the power converter 3 is not required to be supplied with electric power, the parasitic diodes of the synchronous MOS transistor 34 on the electric energy transmission channel and the electric energy transmission channel are cut off at the same time, thereby achieving true turn-off, and avoiding the problems of electric energy waste and device damage caused in the conventional technology. And the power converter 3 of the application is only suitable for one MOS tube to solve the problems in the traditional technology, and has low cost. Meanwhile, since the switching MOS transistor 311 is in a conducting state during charging and discharging of the power converter 3, the circuit can be shared, and then the switching point (V) shown in fig. 2 can be avoided_x) The voltage in the 32 sections of the wave pattern is too high to cause the damage of the control MOS tube 37.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.