Power supply module capable of preventing reverse input of counter electromotive force and power supply device

Abstract

The utility model provides a power supply module and a power supply device capable of preventing reverse input of back electromotive force, and relates to the technical field of power supplies, the power supply module comprises a power supply circuit and a back electromotive force preventing circuit, the output end of the power supply circuit is connected with the input end of the back electromotive force preventing circuit, and the output end of the back electromotive force preventing circuit is connected with a driving load; the anti-back electromotive force circuit comprises an MOS tube circuit and a triode circuit, the MOS tube circuit is arranged between the output end of the power supply circuit and the driving load to form a power supply control loop, the triode circuit and the MOS tube circuit are connected with the power supply input end of the power supply module, and the triode circuit is used for controlling the power supply control loop to be switched on when positive voltage is input into the power supply input end; the triode circuit is also used for controlling the power supply control loop to be closed when no positive voltage is input to the power supply input end. The utility model can prevent reverse input of counter electromotive force, reduce the heating value of the power supply module, and ensure the conversion efficiency of the power supply module and the stability of output voltage.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply, in particular to a power supply module and a power supply device capable of preventing reverse input of back electromotive force. Background Art

[0002] In many fields, motors, steering gears and other drive devices are used, and these drive devices require corresponding power supply modules. When there is a positive voltage input to the input end of the power module, its output end outputs voltage and current to supply motors, steering gears and other drive devices; when there is no positive voltage input to the input end, the back electromotive force generated by artificially rotating the motor and steering gear will be reversely input into the power module from the output end of the power module, causing damage to the circuit of the power module.

[0003] Most of the commonly used power modules currently do not have the function of preventing reverse input of back electromotive force. Some power modules with this function use diodes for reverse protection. The diode itself will produce a voltage drop, and the voltage drop changes with the current, causing the output voltage of the power module to be unstable; secondly, the voltage drop generated by the diode will cause the diode to generate a lot of heat, further increasing the overall heat generation of the power module, resulting in reduced efficiency, shortened life, and reduced stability of the power module. Utility Model Content

[0004] In view of this, the utility model provides a power supply module and a power supply device with the function of preventing reverse input of back electromotive force, which can prevent the back electromotive force of motors, steering gears, etc. from being reversely input into the power supply module from the output end when there is no positive input power supply, causing circuit damage. At the same time, it can reduce the heat generated by the power supply module, improve the conversion efficiency of the power supply module, and increase the output voltage stability.

[0005] According to the first aspect of the utility model, a power supply module with a function of preventing reverse input of back electromotive force comprises: a power supply circuit and an anti-back electromotive force circuit, wherein the output end of the power supply circuit is connected to the input end of the anti-back electromotive force circuit, the output end of the anti-back electromotive force circuit is connected to a driving load, and the anti-back electromotive force circuit is used to allow the power supply circuit to supply power to the driving load when the power supply module has a positive voltage input, and to prevent the back electromotive force generated by the driving load from flowing into the power supply circuit in reverse when the power supply module has no positive voltage input;

[0006] Among them, the anti-back electromotive force circuit includes a MOS tube circuit and a triode circuit. The MOS tube circuit is arranged between the output end of the power supply circuit and the driving load to form a power supply control loop. The triode circuit is connected to the MOS tube circuit and the power input end of the power module. The triode circuit is used to control the power supply control loop to be turned on when a positive voltage is input to the power supply input end; the triode circuit is also used to control the power supply control loop to be turned off when no positive voltage is input to the power supply input end.

[0007] Optionally, the MOS transistor circuit includes a MOS transistor Q1 and a resistor R8;

[0008] The drain D end of the MOS tube Q1 is connected to the output end of the power supply circuit, the source S end of the MOS tube Q1 is connected to the driving load, the gate G end of the MOS tube Q1 is connected to the triode circuit, and the resistor R8 is connected between the source S end and the gate G end of the MOS tube Q1.

[0009] Optionally, the transistor circuit includes a transistor Q2;

[0010] The collector C terminal of the transistor Q2 is connected to the gate G terminal of the MOS transistor Q1, the emitter E terminal of the transistor Q2 is grounded, and the base B terminal of the transistor Q2 is connected to the power input terminal of the power module;

[0011] The transistor Q2 is used to be turned on when a positive voltage is input to the power module, so that the voltage difference between the source S terminal and the gate G terminal of the MOS tube Q1 is greater than the turn-on threshold voltage of the MOS tube Q1, and to be turned off when no positive voltage is input to the power module, so that the voltage difference between the source S terminal and the gate G terminal of the MOS tube Q1 is less than the turn-on threshold voltage of the MOS tube Q1.

[0012] Optionally, the triode circuit further includes a resistor R11 and a resistor R12;

[0013] One end of the resistor R11 and the resistor R12 is connected to the base B end of the transistor, the other end of the resistor R11 is connected to the power input end of the power module, and the other end of the resistor R12 is grounded;

[0014] The resistor R11 and the resistor R12 constitute a voltage-dividing resistor, which is used to convert the input voltage of the power input terminal into the working voltage of the triode circuit.

[0015] Optionally, the transistor Q2 is an NPN transistor.

[0016] Optionally, the MOS transistor Q1 is a P-type MOS transistor.

[0017] Optionally, the power supply circuit includes a DC-DC conversion module, the input end of the DC-DC conversion module is connected to the power input end of the power supply module, and the DC-DC conversion module is used to convert the input voltage of the power input end into an operating voltage to drive the load.

[0018] A power supply device according to an embodiment of the second aspect of the utility model includes a power supply module having the function of preventing reverse input of back electromotive force in the first aspect or its implementation manners.

[0019] One of the above technical solutions has at least the following advantages or beneficial effects:

[0020] A power supply module with the function of preventing reverse input of back electromotive force in the embodiment of the utility model provides a back electromotive force prevention circuit including a MOS tube circuit and a triode circuit, a MOS tube circuit is arranged between the output end of the power supply circuit and the driving load to form a power supply control loop, the triode circuit and the MOS tube circuit and the power supply input end of the power supply module are connected, and the power supply control loop is controlled to be turned on when a positive voltage is input to the power supply input end by the triode circuit, and the power supply control loop is controlled to be turned off when no positive voltage is input to the power supply input end. For the utility model, by adding a MOS circuit to the output end of the power supply module, it is possible to prevent the back electromotive force of the motor, the steering gear, etc. from being reversely input to the power supply module from the output end to cause circuit damage when there is no positive input power to the power supply module. In addition, since the internal resistance of the MOS tube is small, the heat generated by the power supply module can be reduced, the conversion efficiency of the power supply module can be improved, and the output voltage stability can be increased.

[0021] The power supply device provided in the embodiment of the utility model is provided with the above-mentioned power supply module with the function of preventing reverse input of back electromotive force. Since the power supply module with the function of preventing reverse input of back electromotive force has the above-mentioned technical effect, the power supply device provided with the power supply module with the function of preventing reverse input of back electromotive force should also have the corresponding technical effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0023] Figure 1 A circuit connection diagram of a power module with a function of preventing reverse input of back electromotive force according to an embodiment of the present invention is shown;

[0024] Figure 2 A circuit connection diagram of a power supply circuit according to an embodiment of the present invention is shown.

[0025] In the figure:

[0026] 1-power supply circuit, 11-DC-DC conversion module;

[0027] 2-anti-back electromotive force circuit, 21-MOS tube circuit, 22-transistor circuit. DETAILED DESCRIPTION

[0028] In order to better explain the utility model and facilitate understanding, the utility model is described in detail below with reference to the accompanying drawings and through specific implementation methods. Figure 1 The orientation is used as a reference.

[0029] In many fields, motors, steering gears and other drive devices are used, and these drive devices require corresponding power supply modules. When there is a positive voltage input to the input end of the power module, its output end outputs voltage and current to supply motors, steering gears and other drive devices; when there is no positive voltage input to the input end, the back electromotive force generated by artificially rotating the motor and steering gear will be reversely input into the power module from the output end of the power module, causing damage to the circuit of the power module.

[0030] Most of the commonly used power modules currently do not have the function of preventing reverse input of back electromotive force. Some power modules with this function use diodes for reverse protection. The diode itself will produce a voltage drop, and the voltage drop changes with the current, causing the output voltage of the power module to be unstable; secondly, the voltage drop generated by the diode will cause the diode to generate a lot of heat, further increasing the overall heat generation of the power module, resulting in reduced efficiency, shortened life, and reduced stability of the power module.

[0031] In order to solve at least one of the technical problems existing in the prior art or related technology, the utility model provides a power module and a power supply device with the function of preventing reverse input of back electromotive force, which can prevent the back electromotive force of motors, steering gears, etc. from being reversely input into the power module from the output end when there is no positive input power supply, causing circuit damage. At the same time, it can reduce the heat generated by the power module, improve the conversion efficiency of the power module, and increase the output voltage stability.

[0032] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0033] Combine the following Figure 1 A power module with a reverse input for preventing back electromotive force according to some embodiments of the present invention is described.

[0034] like Figure 1 As shown, the circuit connection structure of the power supply module disclosed in the utility model with the function of preventing reverse input of back electromotive force includes: a power supply circuit 1 and an anti-back electromotive force circuit 2, wherein the output end of the power supply circuit 1 is connected to the input end of the anti-back electromotive force circuit 2, and the output end of the anti-back electromotive force circuit 2 is connected to the driving load VOUT, and the anti-back electromotive force circuit 2 is used to allow the power supply circuit 1 to supply power to the driving load VOUT when the power supply module has a positive voltage input, and to prevent the back electromotive force generated by the driving load VOUT from flowing in reverse into the power supply circuit 1 when the power supply module has no positive voltage input.

[0035] Among them, the anti-back electromotive force circuit 2 includes a MOS tube circuit 21 and a transistor circuit 22. The MOS tube circuit 21 is arranged between the output end of the power supply circuit 1 and the driving load VOUT to form a power supply control loop. The transistor circuit 22 is connected to the MOS tube circuit 21 and the power input end VBAT of the power module. The transistor circuit 22 is used to control the power supply control loop to be turned on when a positive voltage is input to the power input end VBAT; the transistor circuit 22 is also used to control the power supply control loop to be turned off when no positive voltage is input to the power input end VBAT.

[0036] In specific application scenarios, such as Figure 1 As shown, the MOS tube circuit 21 includes a MOS tube Q1 and a resistor R8; the drain D end of the MOS tube Q1 is connected to the output end of the power supply circuit 1, the source S end of the MOS tube Q1 is connected to the driving load VOUT, the gate G end of the MOS tube Q1 is connected to the triode circuit 22, and the resistor R8 is connected between the source S end and the gate G end of the MOS tube Q1. Among them, the MOS tube Q1 can be a P-type MOS tube. It can be understood that when the MOS tube Q1 is an N-type MOS tube, the technical solution provided in the utility model is also applicable when the circuit connection mode is modified. Under the action of the equipotential resistor (i.e., the resistor R8), when there is a voltage difference between the source S end voltage and the gate G end voltage of the PMOS tube Q1, the MOS tube Q1 is turned on; when the voltage difference between the source S end voltage and the gate G end voltage of the PMOS tube Q1 is close to 0V, the MOS tube Q1 is not turned on, and at this time, the back electromotive force of the motor, steering gear, etc. cannot flow into the power supply circuit 1 in reverse.

[0037] In specific application scenarios, such as Figure 1 As shown, the transistor circuit 22 includes a transistor Q2; the collector C end of the transistor Q2 is connected to the gate G end of the MOS tube Q1, the emitter E end of the transistor Q2 is grounded, and the base B end of the transistor Q2 is connected to the power input end VBAT of the power module; wherein the transistor Q2 can be an NPN transistor. It can be understood that when the transistor Q2 is a PNP transistor, the technical solution provided in the utility model is also applicable when the circuit connection mode is modified. Among them, the conduction threshold voltage can vary with different MOS tubes, and its value range can be, for example, 2.5V to 6V, and the specific value can be set according to the model of the MOS tube Q1.

[0038] Correspondingly, when the power module has a positive voltage input, the base-emitter voltage V BE (Q2) is not 0, transistor Q2 is turned on, and the collector voltage V C(Q2) is 0, the voltage at the gate G terminal of the MOS tube Q1 is close to 0V, and at the same time, the VCC voltage at the output terminal of the power supply circuit 1 is output to the source S terminal of the MOS tube Q1 through the body diode of the MOS tube Q1. At this time, the voltage at the source S terminal is close to VCC, and the voltage at the source S terminal of the PMOS tube Q1 is greater than the voltage at the gate G terminal, and the voltage difference is greater than the conduction threshold voltage of the MOS tube Q1, so that the MOS tube Q1 is fully turned on, and the output voltage drives the load.

[0039] When there is no positive voltage input to the power module, the base-emitter voltage V BE (Q2) is 0, the transistor Q2 is not turned on, and under the action of the equipotential resistor (i.e., resistor R8), even if there is a reverse input of the back electromotive force at the source S end of the MOS tube Q1, the voltage difference between the gate G end and the source S end of the MOS tube Q1 is close to 0V, which is much smaller than the conduction threshold voltage of the MOS tube Q1. The back electromotive force (the current generated by it) cannot flow in reverse to the power module, thereby preventing the power module circuit from being damaged.

[0040] That is, the transistor Q2 is used to be turned on when the power module has a positive voltage input, so that the voltage difference between the source S terminal and the gate G terminal of the MOS tube Q1 is greater than the conduction threshold voltage of the MOS tube Q1, and to be turned off when the power module has no positive voltage input, so that the voltage difference between the source S terminal and the gate G terminal of the MOS tube Q1 is less than the conduction threshold voltage of the MOS tube Q1.

[0041] Correspondingly, such as Figure 1 As shown, the transistor circuit 22 also includes a resistor R11 and a resistor R12; one end of the resistor R11 and the resistor R12 is connected to the base B end of the transistor, the other end of the resistor R11 is connected to the power input terminal VBAT of the power module, and the other end of the resistor R12 is grounded; wherein the resistor R11 and the resistor R12 constitute a voltage divider resistor, which is used to convert the input voltage of the power input terminal VBAT into the working voltage of the transistor circuit.

[0042] In specific application scenarios, such as Figure 2 As shown, the power supply circuit 1 includes a DC-DC conversion module 11, the input end of the DC-DC conversion module 11 is connected to the power input end VBAT of the power module, and the DC-DC conversion module 11 is used to convert the input voltage of the power input end into an operating voltage VCC for driving the load.

[0043] The power module with the function of preventing reverse input of back electromotive force provided by the utility model has the following beneficial effects: by adding a MOS circuit at the output end of the power module, it can prevent the reverse input of the back electromotive force of the motor, steering gear, etc. from the output end of the power module to the power module when there is no positive input power supply, thereby causing circuit damage. In addition, since the internal resistance of the MOS tube is small, the heat generated by the power module can be reduced, the conversion efficiency of the power module can be improved, and the output voltage stability can be increased.

[0044] A power supply device according to an embodiment of the utility model comprises a power supply module having the function of preventing reverse input of back electromotive force according to any of the above embodiments.

[0045] Among them, since the power supply device includes any power supply module in the above-mentioned first aspect that has the function of preventing reverse input of back electromotive force, it has the beneficial effects of any of the above-mentioned embodiments, which will not be repeated here.

[0046] In the description of the present utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0047] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] In the present utility model, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0049] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "exemplary embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0050] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A power module with a function of preventing reverse input of back electromotive force, characterized in that: include: A power supply circuit and an anti-back electromotive force circuit, wherein the output end of the power supply circuit is connected to the input end of the anti-back electromotive force circuit, and the output end of the anti-back electromotive force circuit is connected to a driving load, and the anti-back electromotive force circuit is used to allow the power supply circuit to supply power to the driving load when the power supply module has a positive voltage input, and to prevent the back electromotive force generated by the driving load from flowing in the reverse direction into the power supply circuit when the power supply module has no forward voltage input; Among them, the anti-back electromotive force circuit includes a MOS tube circuit and a triode circuit, the MOS tube circuit is arranged between the output end of the power supply circuit and the driving load to form a power supply control loop, the triode circuit is connected to the MOS tube circuit and the power input end of the power module, and the triode circuit is used to control the power supply control loop to be turned on when a positive voltage is input to the power supply input end; the triode circuit is also used to control the power supply control loop to be turned off when no positive voltage is input to the power supply input end.

2. The power module with the function of preventing reverse input of back electromotive force according to claim 1, characterized in that: The MOS tube circuit includes a MOS tube Q1 and a resistor R8; The drain D end of the MOS tube Q1 is connected to the output end of the power supply circuit, the source S end of the MOS tube Q1 is connected to the driving load, the gate G end of the MOS tube Q1 is connected to the triode circuit, and the resistor R8 is connected between the source S end and the gate G end of the MOS tube Q1.

3. The power module with the function of preventing reverse input of back electromotive force according to claim 2, characterized in that: The triode circuit includes a triode Q2; The collector C terminal of the transistor Q2 is connected to the gate G terminal of the MOS transistor Q1, the emitter E terminal of the transistor Q2 is grounded, and the base B terminal of the transistor Q2 is connected to the power input terminal of the power module; The transistor Q2 is used to be turned on when the power module has a positive voltage input, so that the voltage difference between the source S terminal and the gate G terminal of the MOS tube Q1 is greater than the turn-on threshold voltage of the MOS tube Q1, and to be turned off when the power module has no positive voltage input, so that the voltage difference between the source S terminal and the gate G terminal of the MOS tube Q1 is less than the turn-on threshold voltage of the MOS tube Q1.

4. The power module with the function of preventing reverse input of back electromotive force according to claim 3, characterized in that: The triode circuit also includes a resistor R11 and a resistor R12; One end of the resistor R11 and the resistor R12 is connected to the base B end of the transistor, the other end of the resistor R11 is connected to the power input end of the power module, and the other end of the resistor R12 is grounded; The resistor R11 and the resistor R12 constitute a voltage-dividing resistor, which is used to convert the input voltage of the power input terminal into the operating voltage of the triode circuit.

5. The power module with the function of preventing reverse input of back electromotive force according to claim 3, characterized in that: The transistor Q2 is an NPN transistor.

6. The power module with the function of preventing reverse input of back electromotive force according to claim 2, characterized in that: The MOS tube Q1 is a P-type MOS tube.

7. The power module with the function of preventing reverse input of back electromotive force according to claim 1, characterized in that: The power supply circuit includes a DC-DC conversion module, the input end of the DC-DC conversion module is connected to the power input end of the power supply module, and the DC-DC conversion module is used to convert the input voltage of the power input end into the working voltage of the driving load.

8. A power supply device, characterized in that: include: A power module with the function of preventing reverse input of back electromotive force as claimed in any one of claims 1 to 7.

Images