CN115622019A - A power supply switching circuit, a power supply switching device and a power supply system - Google Patents

Abstract

The present application discloses a power supply switching circuit, a power supply switching device and a power supply system. The power supply switching circuit includes a first power supply access unit, a second power supply connection unit, a switch switching unit and a power output unit; the first power supply connection unit is Power over Ethernet access unit, the second power access unit is other access units different from the first power access unit; the switch switching unit is connected between the first power access unit and the second power access unit and the power supply Between the output units, it is used to control the conduction between the first power input unit or the second power input unit and the power output unit, so that it can avoid using different power supply methods to supply power to the electrical equipment at the same time, resulting in abnormal operation of the electrical equipment Case.

Description

A power supply switching circuit, a power supply switching device and a power supply system

technical field

The present application relates to the technical field of Ethernet, and in particular to a power supply switching circuit, a power supply switching device and a power supply system.

Background technique

A current active Ethernet (Power Over Ethernet, POE) system includes a power sourcing equipment (Power Sourcing Equipment, PSE) and a power receiving equipment (Power Device, PD).

The PSE device can supply power to the PD device through the Ethernet. However, when the PD device is used alone, since the PD device cannot be powered through the Ethernet, it is relatively difficult to use the PD device alone. To improve this problem, other power access methods may be provided for the PD device. However, when different power supply modes are used to supply power to the PD device at the same time, the PD device may work abnormally.

Contents of the invention

The present application aims to provide a power supply switching circuit, a power supply switching device, and a power supply system, so as to solve the problem that the PD equipment may work abnormally when the interfaces corresponding to different power supply modes of the PD equipment are connected.

And the present application adopts the following schemes for solving the above-mentioned technical problems.

In a first aspect, the present application provides a power supply switching circuit, and the power supply switching circuit includes:

A first power access unit, the first power access unit is a Power over Ethernet access unit;

a second power access unit, the second power access unit is different from the first power access unit;

power output unit;

A switch switching unit, the switch switching unit is connected between the first power input unit and the second power input unit and the power output unit, and is used to control the first power input unit or the The second power input unit is connected to the power output unit.

In some embodiments of the present application, the first power access unit is configured to connect to a power-over-Ethernet device, identify the first power provided by the power-over-Ethernet device, and adjust the first power;

The second power access unit is configured to access an access power supply device different from the Ethernet power supply device, identify the second power provided by the access power supply device, and adjust the second power supply;

The switch switching unit is used to control the conduction between the first power input unit or the second power input unit and the power output unit;

The power output unit is used to convert the third electric energy output by the switching unit into fourth electric energy matching with the electric equipment.

In some embodiments of the present application, the access priority of the first power access unit is greater than the access priority of the second power access unit.

In some embodiments of the present application, the switching unit is configured to control the first power access unit or the The second power input unit is connected to the power output unit, and the first input end of the switching unit is electrically connected to the output end of the first power input unit.

In some embodiments of the present application, the switching unit includes

a first switch unit, a first detection unit, a second switch unit and a second detection unit;

The first switch unit is arranged between the first power input unit and the power output unit, and the first detection unit is coupled between the first switch unit and the first power input unit Between; the first switch unit is signal-connected to the first detection unit, and the first switch unit is used to control the first power access unit and the power supply according to the output signal of the first detection unit The conduction of the output unit;

The second switch unit is arranged between the second power input unit and the power output unit, and the second detection unit is coupled between the first switch unit and the first power input unit on the connection point between; the second switch unit is signal-connected to the second detection unit, and the second switch unit is used to control the second power access unit and the second detection unit according to the output signal of the second detection unit the conduction of the power output unit;

Wherein, the first switch unit and the second switch unit are mutually exclusive, and the conduction priority of the first switch unit is greater than the conduction priority of the second switch unit.

In some embodiments of the present application, the access priority of the second power access unit is greater than the access priority of the first power access unit.

In some embodiments of the present application, the switching unit is configured to control the first power access unit or the The second power input unit is connected to the power output unit, and the second input end of the switching unit is electrically connected to the output end of the second power input unit.

In some embodiments of the present application, the switching unit includes a third switching unit, a third detecting unit, a fourth switching unit and a fourth detecting unit;

The third switch unit is arranged between the power output unit and the first power input unit, the fourth switch unit is arranged between the power output unit and the second power input unit, The third detection unit is respectively coupled to the connection point between the fourth switch unit and the second power supply input unit and the connection point between the third switch unit and the first power supply connection unit; The third switch unit and the fourth switch unit are signal-connected to the third detection unit respectively, and the third switch unit is used to control the first power access unit and the third detection unit according to the signal of the third detection unit. shutting off between the power output units and controlling the conduction between the second power input unit and the power output unit;

Wherein, the third switch unit and the fourth switch unit are mutually exclusive, and the turn-on priority of the fourth switch unit is greater than the turn-on priority of the third switch unit.

In some embodiments of the present application, the first power access unit includes an isolation converter, and the isolation converter is used to adjust the fifth electric energy input by the Ethernet power supply device to the switching unit;

Wherein, the isolation converter is connected to the switching unit.

In some embodiments of the present application, the isolation converter includes a flyback converter.

In a second aspect, the present application further provides a power supply switching device, including the above-mentioned power supply switching circuit.

In the third aspect, the present application also provides a power supply system, the power supply system includes a first power supply device, a second power supply device, a power consumption device and the above-mentioned switching device, and the power supply switching device is connected to the first power supply device and between the second power supply device and the power consumption device, the first power supply device is a power over Ethernet device, and the second power supply device is an access power supply device different from the power over Ethernet device.

A power supply switching circuit, a power supply switching device and a power supply system provided by the present application, the power supply switching circuit includes a first power supply access unit, a second power supply connection unit, a switch switching unit and a power output unit; the first power supply connection The unit is a power-over-Ethernet access unit, and the second power access unit is another access unit different from the first power access unit; by setting the switch switching unit to control the first power access unit or the second power access unit and The power output unit is turned on, so that both the first power access unit and the second power access unit cannot be connected to the power output unit at the same time, thereby avoiding the power consumption of the electrical equipment due to the two simultaneously supplying power to the electrical equipment. Circumstances of abnormal work.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

FIG. 1 is a schematic structural diagram of a power supply switching circuit provided by an embodiment of the present application;

Fig. 2 is a schematic structural diagram of a switching unit provided by an embodiment of the present application;

Fig. 3 is a schematic diagram of the circuit structure of the switching unit in Fig. 2;

FIG. 4 is a schematic diagram of the control sequence of the switching unit in FIG. 3 of the present application;

FIG. 5 is a schematic structural diagram of a switching unit provided in another embodiment of the present application;

FIG. 6 is a schematic diagram of the circuit structure of the switching unit in FIG. 5;

FIG. 7 is a schematic diagram of the control sequence of the switching unit in FIG. 6 of the present application;

FIG. 8 is a schematic structural diagram of a power supply switching circuit provided by another embodiment of the present application;

FIG. 9 is a schematic structural diagram of a power supply switching circuit provided by another embodiment of the present application.

Description of main component symbols:

1-first power access unit, 2-second power access unit, 3-switch switching unit, 4-power output unit, 31-first switch unit, 32-second switch unit, 33-first detection unit , 34—the second detection unit, 35—the third switch unit, 36—the fourth switch unit, 37—the third detection unit.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of this application. In the description of the present application, "plurality" means two or more, unless otherwise specifically defined.

In this application, the word "exemplary" is used to mean "serving as an example, illustration or illustration". Any embodiment described in this application as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is given to enable any person skilled in the art to make and use this application. In The following description lists the details for the purpose of explanation. It should be understood that those of ordinary skill in the art can think that the application can be realized without using these specific details. In other embodiments, no Known structures and processes are set forth in detail to avoid unnecessary details making the description of the application obscure.Therefore, the application is not intended to be limited to the illustrated embodiments, but is consistent with principles disclosed in the application Consistent with the widest range.

Referring to FIG. 1 , an embodiment of the present application provides a power supply switching circuit. The power supply switching circuit includes a first power input unit 1 , a second power input unit 2 , a power output unit 4 and a switch switching unit 3 .

Wherein, the first power access unit 1 may be a Power over Ethernet access unit. At this time, the first power access unit 1 is configured to connect to a power over Ethernet device (that is, a PSE device in a POE system), identify the first power provided by the power over Ethernet device, and adjust the first power.

The second power access unit 2 is different from the first power access unit 1 . That is to say, the second power access unit 2 is another type of power access unit different from the Power over Ethernet access unit. The second power access unit 2 is used to access an access power supply device different from the Ethernet power supply device, identify the second power provided by the access power supply device, and adjust the second power supply.

The switch switching unit 3 is connected between the first power input unit 1 and the second power input unit 2 and the power output unit 4, and is used to control the first power input unit 1 or the second power input unit 2 and The power output unit 4 is turned on.

The power output unit 4 is used for connecting electrical equipment. Specifically, the power output unit 4 is used to convert the electric energy output by the switching unit 3 into electric energy matching the electric equipment.

At present, due to the different types of the first power access unit 1 and the second power access unit 2, the output of the two will not be exactly the same. The device is not working properly. However, in the embodiment of the present application, the switching unit 3 is set to control the conduction between the first power supply unit 1 or the second power supply unit 2 and the power output unit 4, so that the first power supply unit 1 and the second power supply unit 2 Both of them cannot be connected to the power output unit 4 at the same time, thus, it is possible to avoid the situation that different power supply methods are used to supply power to the electrical equipment at the same time, resulting in abnormal operation of the electrical equipment.

In a possible example, the first power access unit 1 is used as the main mode for power supply. At this time, the access priority of the first power access unit 1 is higher than the access priority of the second power access unit 2 . That is, when the first power input unit 1 is connected to the first power supply and the second power input unit 2 is connected to the second power supply, the switch switching unit 3 preferentially connects the first power input unit 1 with the power output unit 4 , the connection between the second power input unit 2 and the power output unit 4 is cut off.

For example, when the second power access unit 2 is a USB-C input voltage regulation circuit unit, the input end of the first power access unit 1 is connected to the output end of the PSE device, and the power supply device supplies power to the power supply switching circuit In this case, regardless of whether an external USB power supply device is connected to the input end of the second power supply unit 2, the switch switching unit 3 preferentially selects the first power supply unit 1 and communicates with the power output unit 4, that is, the PSE device preferentially switches through the power supply The circuit supplies power to the electrical equipment; through the switch switching unit, the circuit between the second power access unit 2 and the power output unit 4 is disconnected, so that the circuit between the USB power supply equipment and the electrical equipment is disconnected; The first power input unit 1, the switch switching unit 3, and the power output unit 4 supply power to the electrical equipment, and the first power input unit 1 and the second power input unit are connected through the switch switching unit in the power supply switching circuit. 2 Separated on the line, to avoid the common mode noise of the USB power supply device will interfere with the Ethernet data transmission when the PSE device supplies power to the electric device, resulting in abnormal operation of the electric device.

In some embodiments in which the first power access unit 1 is used as the main mode for power supply, the switching unit 3 is used to control the second The first power input unit 1 or the second power input unit 2 is connected to the power output unit 4 , and the first input end of the switching unit 3 is electrically connected to the output end of the first power input unit 1 .

Wherein, the first voltage condition includes a preset voltage value range, for example, the first voltage condition is: the voltage value of the voltage at the first input terminal is greater than or equal to the first preset voltage value, and the preset voltage value can be set according to the specific switching unit. Set the voltage value range, here is just an example.

Please refer to FIG. 2 , in some possible examples where the first power access unit 1 is used as the main mode for power supply, the switch switching unit 3 may include a first switch unit 31 , a first detection unit 33 , and a second switch unit 32 and a second detection unit 34;

The first switch unit 31 is arranged between the first power input unit 1 and the power output unit 4, and the first detection unit 33 is coupled between the first switch unit 31 and the first power input unit 1; the first switch unit 31 is connected to the signal of the first detection unit 33, and the first switch unit 31 is used to control the conduction of the first power input unit 1 and the power output unit 4 according to the signal of the first detection unit 33;

The second switch unit 32 is arranged between the second power input unit 2 and the power output unit 4, and the second detection unit 34 is coupled between the first switch unit 31 and the first power input unit 1; the second switch unit 32 is signal-connected to the second detection unit 34, and the second switch unit 32 is used to control the conduction of the second power input unit 2 and the power output unit 4 according to the signal of the second detection unit 34;

Wherein, the first switch unit 31 and the second switch unit 32 are mutually exclusive, and the conduction priority of the first switch unit 31 is greater than that of the second switch unit 32 .

For example, when the first detection unit 33 and the second detection unit 34 detect that the power-over-Ethernet device is charged into the first power access unit 1, that is, the first detection unit 33 and the second detection unit 34 detect the switching unit 3’s first input terminal voltage (or the output terminal voltage of the first power access unit 1), the first detection unit 33 controls the first switch unit 31 to conduct through its own output signal, and the second detection unit 34 controls the first switch unit 31 to conduct through its own output signal. The output signal controls the second switch unit 32 to turn off, so as to avoid the interference of Ethernet data transmission when both POE power supply and different POE power supply methods are used to supply power to the electrical equipment at the same time, resulting in abnormal operation of the electrical equipment.

In some possible examples, the first detection unit 33 and the second detection unit 34 may be the same detection unit, and the output terminals of the same detection unit are respectively connected to the control terminal of the first switch unit 31 and the control terminal of the second switch unit 32 .

In some embodiments, the first detection unit 33 and the second detection unit 34 are connected in parallel to the connection point between the first switch unit 31 and the first power input unit 1 .

In some embodiments, when the input level of the first power access unit 1 is high, the first switch unit 31 is turned on, and the second switch unit 32 is turned off, so that the first power input unit 1 and the power output The unit 4 is turned on, and the PSE device supplies power to the electrical equipment; when the output level of the first power supply unit 1 is low, the first switch unit 31 is turned off, and the second switch unit 32 is turned on, so that the second power supply is connected to The input unit 2 is connected to the power output unit 4, and the USB power supply device supplies power to the electric device.

Please refer to FIG. 3. FIG. 3 is an example circuit diagram of the switching unit 3 shown in FIG. , wherein the first MOS transistor Q1 and the second MOS transistor Q2 are connected in series, and the two are connected in series between the first power input unit 1 and the power output unit 4 .

It should be noted that, ZD1 and ZD2 in FIG. 3 and other figures are Zener diodes, and GND is a ground terminal.

More specifically, the drain (D pole) of the first MOS transistor Q1 is connected to the first power access unit 1, the source (S pole) of the first MOS transistor Q1 is connected to the S pole of the second MOS transistor Q2, and the second The D pole of the MOS transistor Q2 is connected to the power output unit 4 . Wherein, the directions of the parasitic diodes of the first MOS transistor Q1 and the second MOS transistor Q2 are opposite. In addition, the gate (G pole) of the first MOS transistor Q1 and the G pole of the second MOS transistor Q2 are electrically connected to the D pole of the third MOS transistor Q3, and the G pole of the third MOS transistor Q3 is connected to the first detection unit, the first detection unit, and the third MOS transistor Q3. The S pole of the three MOS transistors Q3 is grounded.

In some embodiments, the first MOS transistor Q1 and the second MOS transistor Q2 are PMOS transistors; the third MOS transistor Q3 is an NMOS transistor.

In some embodiments, when the input level of the first power access unit 1 is at a high level, the first switch unit 31 is turned on; when the output level of the first power access unit 1 is at a low level, the first switch Unit 31 is off.

Further, when the input level of the first power access unit 1 is at a high level, the third MOS transistor Q3 is turned on, and the first MOS transistor Q1 and the second MOS transistor Q2 are turned on, realizing the first power access unit 1 and the conduction of the power output unit 4.

More specifically, when the output level of the first power access unit 1 is low, the third MOS transistor Q3 is disconnected, and the first MOS transistor Q1 and the second MOS transistor Q2 are disconnected to realize the first power access Disconnection of unit 1 and power output unit 4.

Please continue to refer to FIG. 3, the second switch unit 32 may include a fourth MOS transistor Q4, a fifth MOS transistor Q5, and a sixth MOS transistor Q6, wherein the fourth MOS transistor Q4 is connected in series between the second power supply input terminal and the power supply output terminal Between them, the D pole of the fourth MOS transistor Q4 is connected to the second power supply input terminal, and the S pole of the fourth MOS transistor Q4 is connected to the power supply output terminal.

Further, the D pole of the fifth MOS transistor Q5 is connected to the G pole of the fourth MOS transistor Q4, and the S pole is grounded. The D pole of the sixth MOS transistor Q6 is connected to the G pole of the fifth MOS transistor Q5 , the S pole of the sixth MOS transistor Q6 is grounded, and the G pole of the sixth MOS transistor Q6 is connected to the output terminal of the second detection unit 34 .

In some embodiments, the fourth MOS transistor Q4 is a PMOS transistor, and the fifth MOS transistor Q5 and the sixth MOS transistor Q6 are NMOS transistors. In some embodiments, the third MOS transistor Q3, the fifth MOS transistor Q5, and the sixth MOS transistor Q6 can all be replaced by: triodes, or other switch tubes that can realize the same circuit function, or are composed of switch tubes A circuit unit that can realize the same circuit function.

In some embodiments, Zener diodes, and / or resistance.

Please refer to FIG. 4, which shows the control sequence of the first switch unit 31 and the second switch unit 32 in the circuit diagram shown in FIG. 3, specifically:

In FIG. 4, the PSE signal is the output voltage signal of the PSE device, that is, the input voltage signal of the first power access unit 1, and the VIN-USB signal is the output voltage signal of the USB power supply device, that is, the voltage signal of the second power access unit 2. Input terminal voltage signal;

The VO_PSE signal is the input voltage signal of the first input terminal VO_PSE of the switch switching unit 3 in FIG. 3 , that is, the output terminal voltage signal of the first power access unit 1;

The PSE_IN signal is the output voltage signal of the output terminal PSE_IN of the first detection unit 33 in FIG. 3 , that is, the control signal of the control terminal of the first switch unit 31;

The USB_nEN signal is the output voltage signal of the output terminal USB_nEN of the second detection unit 34 in FIG. 3 , that is, the control signal of the control terminal of the second switch unit 32;

The input voltage_device-to-device (VIN_Device-to-Device, VIN_D2D) signal is the output voltage signal of the switching unit 3 in FIG. 3 .

At time t0, the PSE device is connected to the first power input unit 1 in the power supply switching circuit, and both the first detection unit 33 and the second detection unit 34 detect that the output voltage of the first power input unit 1 is greater than or equal to the preset voltage value, and the output signal of the second detection unit 34 is set high, the G electrode potential of the sixth MOS transistor Q6 is high, the sixth MOS transistor Q6 is turned on, the G electrode potential of the fifth MOS transistor Q5 is pulled low, and the fifth MOS transistor Q5 is pulled down. The MOS transistor Q5 is turned off, so that the G electrode of the fourth MOS transistor Q4 is at a high electric position, and the fourth MOS transistor Q4 is turned off, thereby turning off the connection between the second power input unit 2 and the power output unit 4; the first The voltage at the output terminal of the power access unit 1 continues to rise, and when it is higher than a certain value, the output signal of the first detection unit 33 is set high, so that the third MOS transistor Q3 is turned on, and the voltage of the first MOS transistor Q1 and the second MOS transistor Q2 The G pole voltage is pulled down, and then the first MOS transistor Q1 and the second MOS transistor Q2 are turned on, and the first power input unit 1 and the power output unit 4 are connected.

At time t1, the USB power supply device is connected to the second power access unit 2 in the power supply switching circuit; the second power access unit 2 is connected. At this time, because the fourth MOS transistor Q4 is turned off, and the second power access unit The voltage of 2 is lower than the voltage of the first power access unit 1, and the body diode of the fourth MOS transistor Q4 is reversely blocked.

At time t2, the first power access unit 1 is disconnected from the power output unit 4, and the voltage of the power output unit 4 begins to drop slowly due to the presence of the electric load. When it is lower than a certain value, the output signal of the first detection unit 33 pull down, so that the first MOS transistor Q1 and the second MOS transistor Q2 are turned off; when the voltage of the power output unit 4 continues to drop and is lower than the voltage of the second power access unit 2, the body diode of the fourth MOS transistor Q4 is turned on , the second power access unit 2 is connected and starts to supply power. And due to line loss, the voltage of the first power access unit 1 will continue to decrease. When the voltage is lower than the preset value, the output signal of the second detection unit 34 is pulled low, and the sixth MOS transistor Q6 is turned off, and the fifth MOS transistor Q6 is turned off. The transistor Q5 is turned on, and the fourth MOS transistor Q4 is turned on, thereby reducing loss.

In some embodiments, the second power access unit 2 is used as the main mode for power supply. At this time, the access priority of the second power access unit 2 is higher than the access priority of the first power access unit 1 .

In some embodiments of the present application, the switching unit 3 is configured to control the first power supply unit 1 or the second power supply connection when the voltage at the second input end of the switch switching unit 3 satisfies the second voltage condition. The unit 2 is connected to the power output unit 4 , and the second input end of the switching unit 3 is electrically connected to the output end of the second power input unit 2 . For example, when the first power access unit 1 is connected with a PSE device and the second power access unit 2 is connected with a USB power supply device, the switching unit 3 preferentially connects the second power access unit 2 with the power output unit 4, that is The USB power supply device is preferentially selected to supply power to the electric device, and the first power input unit 1 is disconnected from the power output unit 4 .

In some embodiments, the second voltage condition is a predetermined voltage range.

For example, the second voltage condition is: when the voltage value of the second input terminal is greater than or equal to the second preset voltage value, control the second power access unit 2 and the power output unit 4 to conduct; the second voltage condition is: When the voltage value of the second input terminal is lower than the second preset voltage value, the first power input unit 1 and the power output unit 4 are controlled to be turned on.

In some embodiments in which the second power access unit 2 is used as the main mode for power supply, please refer to FIG. 5 , the switch switching unit 3 includes a third switch unit 35, a third detection unit 37, and a fourth switch unit 36;

The third switch unit 35 is arranged between the power output unit 4 and the first power input unit 1, the fourth switch unit 36 is arranged between the power output unit 4 and the second power input unit 2, and the third detection unit 37 The input terminal is coupled with the connection point of the fourth switch unit 36 and the second power access unit 2; the control terminal of the third switch unit 35 and the control terminal of the fourth switch unit 36 are respectively connected to the output terminal signal of the third detection unit 37 The third switch unit 35 is used to control the shutdown between the first power input unit 1 and the power output unit 4 and control the connection between the second power input unit 2 and the power output unit 4 according to the signal of the third detection unit 37. conduction between

Wherein, the third switch unit 35 and the fourth switch unit 36 are mutually exclusive, and the turn-on priority of the fourth switch unit 36 is greater than the turn-on priority of the third switch unit 35 .

In a more specific embodiment, the third switch unit 35 includes a seventh MOS transistor Q7 and an eighth MOS transistor Q8; wherein, the seventh MOS transistor Q7 and the eighth MOS transistor Q8 are connected in series, and the two are connected in series to the The first power input unit 1 and the power output unit 4 .

More specifically, the D pole of the seventh MOS transistor Q7 is connected to the output terminal of the first power access unit 1, the S pole of the seventh MOS transistor Q7 is connected to the S pole of the eighth MOS transistor Q8, and the D pole of the eighth MOS transistor Q8 The pole is connected to the input end of the power output unit 4. The third detection unit 37 includes: a ninth MOS transistor Q9 and an eleventh MOS transistor Q11. The D pole of the ninth MOS transistor Q9 is electrically connected to the G pole of the seventh MOS transistor Q7 and the G pole of the eighth MOS transistor Q8 respectively, and the S pole of the ninth MOS transistor Q9 is grounded. The D pole of the eleventh MOS transistor Q11 is electrically connected to the G pole of the ninth MOS transistor Q9 of the third detection unit 37, the S pole of the eleventh MOS transistor Q11 is grounded, and the G pole of the eleventh MOS transistor Q11 is connected to the second The output end of the power access unit 2 is electrically connected.

More specifically, the fourth switch unit 36 includes a tenth MOS transistor Q10 and a twelfth MOS transistor Q12, the D pole of the tenth MOS transistor Q10 is connected to the output end of the second power input unit 2, and the S pole is connected to the power output unit 4; the D pole of the twelfth MOS transistor Q12 is connected to the G pole of the tenth MOS transistor Q10, the D pole and the S pole of the twelfth MOS transistor Q12 are grounded, and the D pole and the G pole of the twelfth MOS transistor Q12 are connected to the G pole of the tenth MOS transistor Q12. The D poles of the nine MOS transistors Q9 are electrically connected.

In some embodiments, the seventh MOS transistor Q7, the eighth MOS transistor Q8, and the tenth MOS transistor Q10 are all PMOS transistors, and the ninth MOS transistor Q9, the eleventh MOS transistor Q11, and the twelfth MOS transistor Q12 are all NMOS transistors. Tube.

In some embodiments, when the input level of the second power access unit 2 is high, the fourth switch unit 36 is turned on; when the input level of the second power access unit 2 is low, the fourth switch Unit 36 is off. In some embodiments, the ninth MOS transistor Q9, the eleventh MOS transistor Q11, and the twelfth MOS transistor Q12 can all be replaced by: triodes, or other switch tubes that can achieve the same circuit function, or by switch tubes A circuit unit that can realize the same circuit function.

In some embodiments, Zener diodes can be arranged on the seventh MOS transistor Q7, the eighth MOS transistor Q8, the ninth MOS transistor Q9, the tenth MOS transistor Q10, the eleventh MOS transistor Q11 and the twelfth MOS transistor Q12 , and/or resistance.

In a more specific embodiment, please refer to FIG. 7 , the voltage at the output terminal of the second power input unit 2 is lower than the voltage at the output terminal of the first power input unit 1; the control of the first switch unit 31 and the second switch unit 32 The timing is:

In FIG. 7, the POE signal is the output voltage signal of the PSE device, that is, the input voltage signal of the first power access unit 1, and the VIN-USB signal is the output voltage signal of the USB power supply device, that is, the voltage signal of the second power access unit 2. Input terminal voltage signal;

The VO_PSE signal is the input voltage signal of the first input terminal VO_PSE of the switch switching unit 3 in FIG. 6 , that is, the output terminal voltage signal of the first power access unit 1;

The USB_IN signal is the output voltage signal of the output terminal USB_IN of the enable unit in the third detection unit 37 in FIG. 6 , and the enable unit in the third detection unit 37 in FIG. 6 may include a Zener diode ZD1 and at least one resistor;

The VIN_D2D signal is an output voltage signal of the switching unit 3 in FIG. 6 .

At time t0, the PSE device is connected to the first power supply unit 1 in the power supply switching circuit, the USB power supply device is not connected to the second power supply unit 2 in the power supply switching circuit, and the first power supply unit 1 is connected to , the second power access unit 2 is not connected, the output signal USB_IN signal of the enable unit in the third detection unit 37 is set low, the eleventh MOS transistor Q11 is turned off, and the output voltage of the first power access unit 1 is slow When the output voltage of the first power supply connection unit 1 is higher than the second preset voltage value, the ninth MOS transistor Q9 is turned on, the seventh MOS transistor Q7 and the eighth MOS transistor Q8 are turned on, and the first power supply connection The input unit 1 is connected to the power output unit 4; and since the ninth MOS transistor Q9 is turned on, the twelfth MOS transistor Q12 is turned off, and the tenth MOS transistor Q10 is turned off.

At time t1, the USB power supply device is connected to the second power supply unit 2 in the power supply switching circuit, the PSE device is connected to the first power supply unit 1 in the power supply switching circuit, the second power supply unit 2 is connected, and the third The output signal USB_IN of the enabling unit in the detection unit 37 is pulled high, at this time, the eleventh MOS transistor Q11 is turned on, the ninth MOS transistor Q9 is turned off, the seventh MOS transistor Q7 and the eighth MOS transistor Q8 are turned off, and the MOS transistor Q8 is turned off. A disconnection between the power input unit 1 and the power output unit 4 . And because the ninth MOS transistor Q9 is turned off, the twelfth MOS transistor Q12 is turned on, and the tenth MOS transistor Q10 is turned on, so that the second power input unit 2 and the power output unit 4 are connected.

At t2, the USB power supply device is disconnected from the second power access unit 2 in the power supply switching circuit, the PSE device is connected to the first power access unit 1 in the power supply switching circuit, and the second power access unit 2 is disconnected. The output signal USB_IN signal of the enabling unit in the third detection unit 37 is set low, the seventh MOS transistor Q7 and the eighth MOS transistor Q8 are turned on, the tenth MOS transistor Q10 is turned off, and the first power access unit 1 is connected to the power supply again. Output unit 4 is switched on.

Please refer to FIG. 8 , the embodiment of the present application provides another power supply switching circuit, the structure of which is roughly the same as that shown in FIG. 1 , the difference includes the following content.

The first power access unit 1 is used to access the PSE power supply. The first power access unit 1 includes an Ethernet interface, such as an RJ45 interface. In one embodiment, the Ethernet interface may be a shielded interface. The first power access unit 1 is connected to the PSE device through the RJ45 interface, so that the PSE device supplies power to the electric device through the Ethernet.

The power output unit 4 includes a power output interface. In an embodiment, the power output interface may be a USB-C interface. The power output unit 4 is connected to the electrical equipment through the power output interface.

The power supply switching circuit also includes a network signal transmission unit. The network signal transmission unit is used to realize network communication, and transmits signals while supplying power to electrical equipment. The network signal transmission unit may include an Ethernet isolation transformer and an Ethernet controller. The Ethernet isolation transformer and the Ethernet controller are sequentially connected between the Ethernet interface and the power output interface.

The first power access unit 1 also includes an isolation converter. The isolation converter is connected to the switching unit 3 , specifically, between the Ethernet interface and the first input end of the switching unit 3 , and is used to adjust the power input from the Ethernet to the switching unit 3 . By setting the isolation converter to regulate and isolate the power supply part of the Ethernet, it is beneficial to reduce the influence of the common mode noise on the network signal.

In some embodiments, the first power access unit 1 may also include a bridge rectifier circuit. The bridge rectification circuit is connected between the Ethernet interface and the isolation converter.

In the embodiment of the present application, the first power access unit 1 shakes hands with the PSE device to identify its specifications (there are two specifications for the PSE power supply: IEEE802.3af and IEEE802.3at, compared with IEEE802.3af, IEEE802.3at can It can output higher power and be compatible with the existing IEEE802.3af system), and at the same time, it can adjust the voltage and isolate the PSE equipment to avoid the influence of common mode noise on the network signal.

In some embodiments, the power output unit 4 includes a direct current converter (DC-DC converter). The DC converter is connected between the switching unit 3 and the power output interface. By arranging the switching unit 3 on the input side of the DC converter, it is beneficial to reduce the influence on the electric equipment caused by switching different power access units to supply power to the electric equipment. In one embodiment, the DC converter is a step-down converter (Buck converter) or a boost converter.

In a more specific embodiment, the power output unit 4 may also include a switch tube and a protocol IC. The protocol IC is connected to the DC transformer, the switching tube and the power output interface respectively. The protocol IC can communicate with the electrical equipment through the power output interface, adjust the feedback of the DC converter, and output the voltage required by the electrical equipment; the protocol IC and the switching tube The connection can carry out conventional protection actions through the control switch tube to prevent damage to electrical equipment.

In some embodiments, the second power access unit 2 is used for a power delivery protocol (USB Power Delivery, USB-PD) power supply. The second power access unit 2 is provided with a USB-C inlet or a USB PD inlet. The second power access unit 2 may be a USB-C protocol IC. Since the power supply voltage of common USB-PD devices is usually 5V/3A, 9V/3A, 15V/3A and 20V/3A, if there is no voltage regulator module, the USB-PD device will default to 5V output and cannot meet the requirements of some electrical equipment. This problem can be overcome by regulating the input voltage through the second power access unit 2 .

In some embodiments, the second power access unit 2 is used to connect to a USB power supply device, and the USB power supply device has an output interface matching the input interface of the second power access unit 2 . For example, the USB power supply device may be a mobile power supply device, a computer, etc., and this is only an example, and there is no excessive limitation on the above USB power supply device.

The flow process of the signal in the power supply switching circuit shown in Figure 8 is: the POE power signal output by the PSE device is connected through the shielded interface, the POE power signal includes the POE power signal and the POE data signal; the POE data signal flows through the Ethernet The isolation transformer and the Ethernet controller are transmitted to the USB-C interface to the electrical equipment; the POE power signal is transmitted to the POE identification and voltage regulation module (corresponding to the first power access unit 1), and the POE identification and voltage regulation module converts the POE power After the signal is adjusted, it is transmitted to the switch switching unit 3; the USB-C power supply signal is transmitted to the USB-C input voltage regulation module (corresponding to the second power supply access unit 2), and the USB-C input voltage regulation module adjusts the USB-C power supply signal to Appropriate USB-C power signals are transmitted to the switching unit 3 .

The switch switching unit 3 is connected to the USB-C output module (corresponding to the power output unit 4). After the POE power signal or USB-C power signal passes through the switch switching unit 3, it is output through the DC-DC converter and the switch tube of the USB-C output module. Transfer to the USB-C interface to the electric device.

Please refer to Figure 9, the embodiment of the present application provides another power supply switching circuit, its structure is roughly the same as the power supply switching circuit shown in Figure 8, the difference is that the isolated converter is a flyback converter, and the DC-DC converter Replaced with a post-stage Buck converter.

An embodiment of the present application further provides a power supply switching device, the power supply switching device includes the power supply switching circuit of any one of the foregoing embodiments.

An embodiment of the present application also provides a power supply system, the power supply system includes a first power supply equipment, a second power supply equipment, power consumption equipment and the above-mentioned power supply switching device, the power supply switching device is connected between the first power supply equipment and the second power supply equipment Between the two equipment and the electrical equipment.

In the above-mentioned embodiments, the descriptions of each embodiment have their own emphases. For the part that is not described in detail in a certain embodiment, refer to the detailed description of other embodiments above, and will not be repeated here.

The basic concept has been described above, obviously, for those skilled in the art, the above detailed disclosure is only an example, and does not constitute a limitation to the present application. Although not expressly stated here, various modifications, improvements and amendments to this application may be made by those skilled in the art. Such modifications, improvements, and amendments are suggested in this application, so such modifications, improvements, and amendments still belong to the spirit and scope of the exemplary embodiments of this application.

Meanwhile, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and/or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that two or more references to "an embodiment" or "an embodiment" or "an alternative embodiment" in different places in this specification do not necessarily refer to the same embodiment . In addition, certain features, structures or characteristics of one or more embodiments of the present application may be properly combined.

In the same way, it should be noted that in order to simplify the expression disclosed in the present application and help the understanding of one or more embodiments of the invention, in the foregoing description of the embodiments of the present application, sometimes multiple features are combined into one embodiment, drawings or descriptions thereof. This method of disclosure does not, however, imply that the subject matter of the application requires more features than are recited in the claims. Indeed, embodiment features are less than all features of a single foregoing disclosed embodiment.

Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximations that can vary depending upon the desired characteristics of individual embodiments. In some embodiments, numerical parameters should take into account the specified significant digits and adopt the general digit reservation method. Although the numerical ranges and parameters used in some embodiments of the present application to confirm the breadth of the scope are approximate values, in specific embodiments, such numerical values are set as precisely as practicable.

Each patent, patent application, patent application publication, and other material, such as article, book, specification, publication, document, etc., cited in this application is hereby incorporated by reference into this application in its entirety, except for the contents of this application Inconsistent or conflicting application history documents are excluded, as are documents (currently or hereafter appended to this application) that limit the broadest scope of the claims of this application. It should be noted that if there is any inconsistency or conflict between the descriptions, definitions, and/or terms used in the attached materials of this application and the content of this application, the descriptions, definitions and/or terms used in this application shall prevail.

The technical solutions provided by the embodiments of the present application have been introduced in detail above. In this paper, specific examples have been used to illustrate the principles and implementation methods of the present application. The descriptions of the above embodiments are only used to help understand the methods and cores of the present application. At the same time, for those skilled in the art, according to the idea of this application, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be construed as limiting the application.

Claims (12)

1. A power supply switching circuit, comprising:

the first power supply access unit is an Ethernet power supply access unit;

a second power access unit different from the first power access unit;

a power supply output unit;

and the switch switching unit is connected between the first power supply access unit and the second power supply access unit and the power supply output unit and is used for controlling the conduction of the first power supply access unit or the second power supply access unit and the power supply output unit.

2. The power supply switching circuit according to claim 1,

the first power supply access unit is used for accessing the Ethernet power supply equipment, identifying first electric energy provided by the Ethernet power supply equipment and adjusting the first electric energy;

the second power supply access unit is used for accessing an access power supply device different from the Ethernet power supply device, identifying second electric energy provided by the access power supply device and adjusting the second electric energy;

the switch switching unit is used for controlling the conduction between the first power supply access unit or the second power supply access unit and the power supply output unit;

and the power supply output unit is used for converting the third electric energy output by the switch switching unit into fourth electric energy matched with the electric equipment.

3. The power switching circuit of claim 2 wherein the access priority of the first power access unit is greater than the access priority of the second power access unit.

4. The power supply switching circuit according to claim 3, wherein the switch switching unit is configured to control the first power access unit or the second power access unit and the power output unit to be turned on when a voltage at a first input end of the switch switching unit satisfies a first voltage condition, and the first input end of the switch switching unit is electrically connected to an output end of the first power access unit.

5. The power supply switching circuit according to claim 4, wherein the switch switching unit includes a first switch unit, a first detection unit, a second switch unit, and a second detection unit;

the first switch unit is arranged between the first power supply access unit and the power supply output unit, and the first detection unit is coupled to a connection point between the first switch unit and the first power supply access unit; the first switch unit is in signal connection with the first detection unit and is used for controlling the conduction of the first power supply access unit and the power supply output unit according to an output signal of the first detection unit;

the second switch unit is arranged between the second power supply access unit and the power supply output unit, and the second detection unit is coupled to a connection point between the first switch unit and the first power supply access unit; the second switch unit is in signal connection with the second detection unit and is used for controlling the conduction of the second power supply access unit and the power supply output unit according to an output signal of the second detection unit;

the first switch unit and the second switch unit are mutually exclusive, and the conduction priority of the first switch unit is greater than that of the second switch unit.

6. The power supply switching circuit of claim 2 wherein the second power access unit has an access priority greater than the access priority of the first power access unit.

7. The power supply switching circuit according to claim 6, wherein the switch switching unit is configured to control the first power access unit or the second power access unit and the power output unit to be turned on when a voltage at a second input terminal of the switch switching unit satisfies a second voltage condition, and the second input terminal of the switch switching unit is electrically connected to an output terminal of the second power access unit.

8. The power supply switching circuit according to claim 7, wherein the switch switching unit includes a third switch unit, a third detection unit, and a fourth switch unit;

the third switching unit is arranged between the power output unit and the first power access unit, the fourth switching unit is arranged between the power output unit and the second power access unit, and the third detection unit is respectively coupled with a connection point of the fourth switching unit and the second power access unit and a connection point of the third switching unit and the first power access unit; the third switching unit and the fourth switching unit are respectively in signal connection with the third detection unit, and the third switching unit is used for controlling the turn-off between the first power access unit and the power output unit and the turn-on between the second power access unit and the power output unit according to the signal of the third detection unit;

the third switching unit and the fourth switching unit are mutually exclusive, and the conduction priority of the fourth switching unit is greater than that of the third switching unit.

9. The power supply switching circuit according to any one of claims 2 to 8,

the first power supply access unit comprises an isolation converter, and the isolation converter is used for regulating fifth electric energy input to the switch switching unit by the Ethernet power supply equipment;

wherein the isolation converter is connected with the switch switching unit.

10. The power supply switching circuit of claim 9, wherein the isolated converter comprises a flyback converter.

11. A power supply switching apparatus comprising the power supply switching circuit according to any one of claims 1 to 10.

12. A power supply system comprising a first power supply device, a second power supply device, a power consumption device, and the power supply switching device of claim 11, wherein the power supply switching device is connected between the power consumption device and both the first power supply device and the second power supply device, the first power supply device is an ethernet power supply device, and the second power supply device is an access power supply device different from the ethernet power supply device.

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