CN223309628U

CN223309628U - Multi-power supply switching circuit and electronic equipment

Info

Publication number: CN223309628U
Application number: CN202422533719.3U
Authority: CN
Inventors: 王世沛
Original assignee: Galaxy Power Group Chengdu Co ltd; Galaxy Power Group Co ltd
Current assignee: Galaxy Power Group Chengdu Co ltd; Galaxy Power Group Co ltd
Priority date: 2024-10-18
Filing date: 2024-10-18
Publication date: 2025-09-05
Anticipated expiration: 2034-10-18

Abstract

The utility model provides a multi-power supply switching circuit and electronic equipment, wherein the multi-power supply switching circuit comprises three paths of 5V input power supply switching modules, two paths of 12V input power supply switching modules, a voltage reduction module and a voltage increase module, each three paths of 5V input power supply switching modules comprises a battery power supply input end, a USB power supply input end, a 5V adapter power supply input end and a 5V switch, each two paths of 12V input power supply switching modules comprises a 12V adapter input end and a 12V switch, the battery power supply input end, the USB power supply input end and the 5V adapter power supply input end are respectively connected with the input end of the 5V switch, the output end of the 5V switch is connected with the input end of the voltage increase module, the output end of the voltage increase module and the input end of the 12V adapter are respectively connected with the input end of the voltage reduction module through the 12V switch, and the output end of the voltage reduction module is connected with the 5V adapter power supply input end. Reasonable distribution and utilization of power can be realized, and convenience is brought to users.

Description

Multi-power supply switching circuit and electronic equipment

Technical Field

The utility model relates to the technical field of power supplies, in particular to a multi-power supply switching circuit and electronic equipment.

Background

Many existing electronic devices are configured with a variety of power interfaces. Conventional low-voltage electronic devices are equipped with power interfaces of 5V, 12V, etc., and some are equipped with internal batteries, and some are equipped with power interfaces of USB interfaces, etc. In order to ensure the safety of the internal circuit module of the equipment, some limitation rules are usually added to the power interface, for example, the power interface cannot be started for use during charging, and a data port at the 5V end can work normally after a 12V power supply is connected. This results in a certain inconvenience in use. The allocation of power supply priority to other electronic devices is not reasonable, such as when the adapter or computer USB is powered, the battery is still engaged in the power supply, which reduces the life of the battery.

Therefore, in order to make the customers more convenient to use the electronic equipment and effectively prevent the risk of wrong power supply, reasonable automatic power supply switching and distribution of the power supply system of the electronic equipment are required.

Disclosure of utility model

The utility model aims to solve the technical problems of providing the multi-power supply switching circuit and the electronic equipment, which can automatically switch and use the optimal power supply line to supply power to the equipment, so that the reasonable distribution and utilization of power supply are realized, and the electronic equipment is convenient for users to use.

In order to solve the technical problems, the first technical scheme adopted by the utility model is as follows:

A multi-power supply switching circuit comprises a three-path 5V input power supply switching module, two paths 12V input power supply switching modules, a buck module and a boost module;

The three-way 5V input power supply switching module comprises a battery power supply input end, a USB power supply input end, a 5V adapter power supply input end and a 5V switching switch, wherein the two-way 12V input power supply switching module comprises a 12V adapter input end and a 12V switching switch, the battery power supply input end, the USB power supply input end and the 5V adapter power supply input end are respectively connected with the input end of the 5V switching switch, the output end of the 5V switching switch is connected with the input end of the boosting module, the output end of the boosting module and the 12V adapter input end are respectively connected with the input end of the step-down module through the 12V switching switch, and the output end of the step-down module is connected with the 5V adapter power supply input end.

Optionally, the output ends of the three paths of 5V input power supply switching modules and the output ends of the two paths of 12V input power supply switching modules are respectively connected with a power supply output end.

Optionally, the 5V switch comprises a first 5V switch, a second 5V switch, a third 5V switch and a fourth 5V switch, the 5V adapter power supply input end is connected with the fourth 5V switch through the first 5V switch, the USB power supply input end is connected with the fourth 5V switch through the second 5V switch, the battery power supply input end is connected with the fourth 5V switch through the third 5V switch, and the fourth 5V switch is connected with the output end of the three-way 5V input power supply switch module.

Optionally, the first 5V change-over switch comprises a PMOS tube Q4 and an NMOS tube Q5, the second 5V change-over switch comprises a PMOS tube Q1, the third 5V change-over switch comprises a PMOS tube Q2, and the fourth 5V change-over switch comprises a PMOS tube Q3 and an NMOS tube Q6;

the power supply input end of the 5V adapter is respectively connected with the grid electrode of the PMOS tube Q1, the drain electrode of the PMOS tube Q4 and the grid electrode of the NMOS tube Q5, the grid electrode of the PMOS tube Q1 is grounded, the drain electrode is connected with the USB power supply input end, the grid electrode of the PMOS tube Q4 is connected with the drain electrode of the NMOS tube Q5, the source electrode of the NMOS tube Q5 is grounded, the source electrode of the PMOS tube Q4 is divided into three paths, one path is connected with the source electrode of the PMOS tube Q1, one path is connected with the grid electrode of the PMOS tube Q3, the grid electrode of the NMOS tube Q6 and the grid electrode of the PMOS tube Q2, the source electrode of the NMOS tube Q6 is grounded, the drain electrode is respectively connected with the grid electrode of the PMOS tube Q3 and the output end of the three-way 5V input power supply switching module, the drain electrode of the PMOS tube Q3 is connected with the battery power supply input end, and the source electrode is connected with the output end of the three-way 5V input power supply switching module.

Optionally, the 12V switch comprises a first 12V switch and a second 12V switch, the input end of the 12V adapter is connected with the first 12V switch and the second 12V switch respectively, the output end of the boost module is connected with the second 12V switch, and the first 12V switch and the second 12V switch are connected with the output ends of the two paths of 12V input power supply switch modules respectively.

Optionally, the first 12V change-over switch comprises an NMOS tube Q9 and a PMOS tube Q8, and the second 12V change-over switch comprises a PMOS tube Q7;

The input end of the 12V adapter is respectively connected with the grid electrode of the NMOS tube Q9, the drain electrode of the PMOS tube Q8 and the grid electrode of the PMOS tube Q7, the source electrode of the NMOS tube Q9 is grounded, the drain electrode is connected with the grid electrode of the PMOS tube Q8, the source electrode of the PMOS tube Q8 is respectively connected with the grid electrode of the PMOS tube Q8 and the output ends of the two paths of 12V input power supply switching modules, the grid electrode of the PMOS tube Q7 is grounded, the source electrode is connected with the output ends of the two paths of 12V input power supply switching modules, and the drain electrode is connected with the output end of the boosting module.

Optionally, the boost module comprises a 5V-to-12V chip U1, a resistor R7 and a diode D1, wherein an enabling end of the chip U1 is connected with an output end of the three-path 5V input power supply switching module through the resistor R7, and an output end of the chip U1 is connected with an output end of the boost module through the diode D1.

Optionally, the chip U1 is an asynchronous boost DC/DC converter chip.

Optionally, the step-down module is an LDO regulator.

The second technical scheme provided by the utility model is as follows:

an electronic device comprising the multi-power switching circuit described above.

The multi-power supply switching circuit has the advantages that the multi-power supply switching circuit can automatically switch and use the optimal power supply line to supply power to equipment according to the current type of the power supply, so that reasonable distribution and utilization of the power supply are realized, in addition, the 5V and 12V power supply can be mutually converted, the limitation of the accessed power supply voltage is avoided, the equipment can work normally, complicated wiring and the trouble of being incapable of being adapted are avoided, and the multi-power supply switching circuit is more convenient for users to use.

Drawings

Fig. 1 is a schematic diagram of basic components of a multi-power switching circuit according to a first embodiment of the present utility model;

Fig. 2 is a schematic diagram of a 5V switch in a multi-power switching circuit according to a second embodiment of the present utility model;

FIG. 3 is a schematic circuit diagram of a 5V switch according to an embodiment of the present utility model;

Fig. 4 is a schematic diagram illustrating a 12V switch in a multi-power switching circuit according to a second embodiment of the present utility model;

FIG. 5 is a schematic circuit diagram of a 12V switch according to an embodiment of the present utility model;

Fig. 6 is a schematic diagram illustrating a boost module in a multi-power switching circuit according to a second embodiment of the present utility model;

Fig. 7 is a schematic diagram of a step-down module in a multi-power switching circuit according to a second embodiment of the utility model.

Description of the reference numerals:

1. the system comprises a three-path 5V input power supply switching module, a 2-path 12V input power supply switching module and a power supply switching module;

3. a buck module; 4, a boosting module; 5, a power supply output end;

11. the power supply input end of the 13, 5V adapter;

14. a 5V change-over switch;

141. The first 5V switch, the second 5V switch, the third 5V switch, the fourth 5V switch and the fourth 5V switch are respectively arranged in the first 5V switch, the second 5V switch, the third 5V switch and the fourth 5V switch;

21. A 12V adapter input, a 22, 12V diverter switch;

221. first 12V change-over switch, 222, second 12V change-over switch.

Detailed Description

In order to describe the possible application scenarios, technical principles, practical embodiments, and the like of the present utility model in detail, the following description is made with reference to the specific embodiments and the accompanying drawings. The embodiments described herein are only for more clearly illustrating the technical aspects of the present utility model, and thus are only exemplary and not intended to limit the scope of the present utility model.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of the phrase "in various places in the specification are not necessarily all referring to the same embodiment, nor are they particularly limited to independence or relevance from other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the technical features mentioned in each embodiment may be combined in any manner to form a corresponding implementable technical solution.

Unless defined otherwise, technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present utility model pertains, and the use of related terms herein is intended only to describe specific embodiments, not to limit the present utility model.

In the description of the present utility model, the term "and/or" is a representation for describing a logical relationship between objects, meaning that three relationships may exist, for example, a and/or B, meaning that there are a, B, and both a and B. In addition, the character "/" herein generally indicates that the front-to-back associated object is an "or" logical relationship.

In the present utility model, terms such as "first" and "second" are used merely to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual number, order, or sequence of such entities or operations.

Without further limitation, the use of the terms "comprising," "including," "having," or other like terms in this specification is intended to cover a non-exclusive inclusion, such that a process, method, or article of manufacture that comprises a list of elements does not include additional elements but may include other elements not expressly listed or inherent to such process, method, or article of manufacture.

In the present utility model, the expressions "greater than", "less than", "exceeding" and the like are understood to exclude the present number, and the expressions "above", "below", "within" and the like are understood to include the present number, as well as the expressions "examining the guideline" and the like. Furthermore, in the description of embodiments of the present utility model, the meaning of "a plurality of" is two or more (including two), and similarly, the expression "a plurality of" is also to be understood as such, for example, "a plurality of" and the like, unless specifically defined otherwise.

In the description of embodiments of the present utility model, spatially relative terms such as "center," "longitudinal," "transverse," "length," "width," "thickness," "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counter-clockwise," "axial," "radial," "circumferential," etc., are used herein as a basis for the description of the embodiments or as a basis for the description of the embodiments, and are not intended to indicate or imply that the devices or components referred to must have a particular position, a particular orientation, or be configured or operated in a particular orientation and therefore should not be construed as limiting the embodiments of the present utility model.

Unless specifically stated or limited otherwise, the terms "mounted," "connected," "affixed," "disposed," and the like as used in the description of embodiments of the utility model should be construed broadly. For example, the "connection" may be a fixed connection, a detachable connection, or an integral connection, may be a mechanical connection, an electrical connection, or a communication connection, may be a direct connection or an indirect connection through an intermediary, or may be a communication between two elements or an interaction relationship between two elements. The specific meaning of the above terms in the embodiments of the present utility model can be understood by those skilled in the art to which the present utility model pertains according to circumstances.

In order to describe the technical contents, the achieved objects and effects of the present utility model in detail, the following description will be made with reference to the embodiments in conjunction with the accompanying drawings.

Referring to fig. 1, a first embodiment of the present utility model is as follows:

the embodiment provides a multi-power supply switching circuit, as shown in fig. 1, which comprises a three-path 5V input power supply switching module 1, two paths 12V input power supply switching modules 2, a buck module 3 and a boost module 4;

The three-way 5V input power supply switching module comprises a battery power supply input end, a USB power supply input end, a 5V adapter power supply input end and a 5V switching switch, the two-way 12V input power supply switching module 2 comprises a 12V adapter input end 21 and a 12V switching switch 22, the battery power supply input end 11, the USB power supply input end 12 and the 5V adapter power supply input end 13 are respectively connected with the input end of the 5V switching switch 14, the output end of the 5V switching switch 14 is connected with the input end of the boosting module 4, the output end of the boosting module 4 and the 12V adapter input end 21 are respectively connected with the input end of the step-down module 3 through the 12V switching switch 22, and the output end of the step-down module 3 is connected with the 5V adapter power supply input end 13.

The output ends of the three paths of 5V input power supply switching modules 1 and the output ends of the two paths of 12V input power supply switching modules 2 are respectively connected with the power supply output end 5. The power supply output end 5 is the main power supply input end of the electronic equipment and supplies power for the electronic equipment.

In this embodiment, the three-way 5V input power switching module, for three conventional 5V power inputs (respectively, battery power supply, USB power supply and 5V adapter), can perform turn-off and turn-on control on corresponding power supply lines according to a preset priority, so as to realize automatic switching and use of an optimal power supply line as a power supply of the electronic device.

The priority is respectively 5V adapter power supply, USB power supply and battery power supply from high to low. The priority is set according to the fact that the battery is a lossy device and the power supply duration is limited, a battery power supply circuit is not used under the condition that USB power supply or 5V adapter power supply exists, the vulnerability of the USB interface is moderate, but equipment such as a computer or a charger is often connected to supply power, the stability and the duration of power supply are inferior to those of 5V adapter power supply, and therefore under the condition that 5V adapter power supply exists, functional USB power supply and a battery power supply loop are not used. Therefore, the automatic switching priority of the power supply line set for the three-way 5V input power supply switching module in the embodiment is set according to the durability and the power supply stability of three 5V power supply inputs, and the automatic switching of the three-way 5V input power supply is reasonable, so that the reasonable distribution and use of the power supply can be realized.

In this embodiment, the two-way 12V input power switching module, for the two-way 12V input power condition (12V adapter power supply and 5V to 12V power supply), can perform turn-off and turn-on control on the corresponding power supply line according to a preset priority, so as to realize automatic switching and use of the optimal power supply line as the power supply of the electronic device.

The priority is that the power supply of the 12V adapter is prioritized over the power supply of 5V to 12V. The priority is set according to the condition that a certain efficiency loss exists when the 5V voltage is increased to 12V, and when the 12V adapter is used for supplying power, the 5V voltage increasing power supply is not used.

In this embodiment, the step-down module performs step-down processing on the 12V power input to 5V to supply power to the circuit requiring 5V power, in order to solve the problem that the circuit requiring 5V power cannot work normally when there is no 5V power input and there is 12V power input. The input end of the step-down module is connected with the output ends of the two paths of 12V input power supply switching modules so as to obtain 12V power supply input.

In this embodiment, the boost module, for the case that there is no 12V power input but there is a 5V power input, and a circuit that partially requires 12V power cannot normally operate, boosts the 5V power input to 12V to supply power to the circuit that requires 12V power. The input end of the step-down module is connected with the output ends of the three paths of 5V input power supply switching modules so as to obtain 5V power supply input.

According to the multi-power supply switching circuit provided by the embodiment, on one hand, the optimal power supply line can be automatically switched to supply power to equipment according to the type of the power supply which is accessed currently, so that reasonable distribution and utilization of the power supply are realized. The power supply device is characterized in that under the condition of being connected with a 5V power supply, a 5V adapter is preferred to supply power, a USB is selected for a second time, a battery is selected for a second time, and under the condition of being connected with a 12V power supply, a 12V adapter is preferred to supply power, and a 5V to 12V power supply is selected for a second time.

On the other hand, the mutual conversion between the 5V power supply and the 12V power supply can be realized, the device can work normally without being limited by the accessed power supply voltage, the trouble of complicated wiring and incapability of adapting is avoided, and the device is more convenient for users to use. Namely, 12V is converted into 5V power supply under the condition that 5V power supply is not connected, and 5V is converted into 12V power supply under the condition that 12V power supply is not connected.

Referring to fig. 2 to 7, a second embodiment of the present utility model is as follows:

The utility model is further expanded based on the first embodiment, and particularly refines the internal modules.

The 5V switch in the multi-power supply switching circuit provided in this embodiment, as shown in fig. 2, includes a first 5V switch 141, a second 5V switch 142, a third 5V switch 143, and a fourth 5V switch 144, where the 5V adapter power supply input terminal 13 is connected to the fourth 5V switch 144 through the first 5V switch 141, the USB power supply input terminal 12 is connected to the fourth 5V switch 144 through the second 5V switch 142, the battery power supply input terminal 11 is connected to the fourth 5V switch 144 through the third 5V switch 143, and the fourth 5V switch 144 is connected to the output terminal of the three-way 5V input power supply switching module.

In this embodiment, the first 5V switch 141 corresponds to the 5V adapter power input 13, the second 5V switch 142 corresponds to the USB power input 12, the third 5V switch 143 corresponds to the battery power input 11, and the fourth 5V switch corresponds to the priority control of the three 5V inputs.

The method comprises the steps of connecting a 5V adapter power supply, switching on a first 5V switch, switching off a second 5V switch and a third 5V switch, cutting off a USB power supply line and a battery power supply line, and switching on a fourth 5V switch, wherein the 5V adapter power supply line is selected as a main power supply line of equipment.

When the USB power supply is connected, the second 5V switch is turned on, the first 5V switch and the third 5V switch are correspondingly turned off to cut off the 5V adapter power supply line and the battery power supply line, and the fourth 5V switch is turned on to select the USB power supply line as the main power supply line of the equipment.

And correspondingly, the first 5V change-over switch and the second 5V change-over switch are turned off, and meanwhile, the fourth 5V change-over switch tube is turned off, so that the 5V adapter power supply line and the USB power supply line are cut off, and the battery power supply line is selected as a main power supply line of the equipment.

In some embodiments, as shown in fig. 3, the first 5V switch 141 includes a PMOS transistor Q4 and an NMOS transistor Q5, the second 5V switch 142 includes a PMOS transistor Q1, the third 5V switch 143 includes a PMOS transistor Q2, and the fourth 5V switch 144 includes a PMOS transistor Q3 and an NMOS transistor Q6;

The power supply input end (namely VIN_5V in FIG. 3) of the 5V adapter is respectively connected with the grid electrode of the PMOS tube Q1, the drain electrode of the PMOS tube Q4 and the grid electrode of the NMOS tube Q5, the grid electrode of the PMOS tube Q1 is grounded, the drain electrode of the PMOS tube Q4 is connected with the drain electrode of the NMOS tube Q5, the source electrode of the NMOS tube Q5 is grounded, the source electrode of the PMOS tube Q4 is divided into three paths, one path is connected with the source electrode of the PMOS tube Q1, one path is connected with the grid electrode of the PMOS tube Q1, one path is respectively connected with the drain electrode of the PMOS tube Q3, the grid electrode of the NMOS tube Q6 and the grid electrode of the PMOS tube Q2, the drain electrode of the NMOS tube Q6 is grounded, the drain electrode of the PMOS tube Q3 is respectively connected with the grid electrode of the PMOS tube Q3 and the output end (namely VOUT_5V in FIG. 3), the grid electrode of the PMOS tube Q3 and the drain electrode of the three paths 5V input power supply switching module are connected with the output end (namely VB5V in FIG. 3), and the drain electrode of the VOUT 2 is connected with the output end of the power supply module (namely VB5V in FIG. 3).

Preferably, the PMOS transistor in the above embodiment has the model SM2313, vds= -20v, vgs= ±12v, vgs (th) = -1.0v, id= -4.2a, and the nmos transistor has the model SM2300, vds=20v, vgs= ±12v, vgs (th) = 1.0v, id=5.1A.

Based on the circuit structure of the three paths of 5V input power supply switching modules, the switching working principle of the three paths of 5V input power supplies is as follows:

When the 5V adapter is connected, the corresponding VIN_5V voltage is 5V, the gate voltage of the NMOS tube Q5 is 5V, |Vgs|=5V|Vgs (th) | so that the NMOS tube Q5 is conducted, the gate voltage of the PMOS tube Q4 is 0V, |Vgs|=5V|Vgs (th) | so that the PMOS tube Q4 is conducted, the gate voltage of the PMOS tube Q1 is 5V, the source voltage is 5V, |Vgs|=0V < |Vgs (th) | so that the PMOS tube Q1 is turned off, the corresponding VUSB is turned off, the gate voltage of the NMOS tube Q6 is 5V, |Vgs|=5V|Vgs (th) | so that the NMOS tube Q6 is conducted, the gate voltage of the PMOS tube Q3 is 0V, |Vgs|=5V|Vgs (th) | so that the PMOS tube Q3 is conducted, the output_5V is the main power supply, the gate voltage of the PMOS tube Q2 is 5 V|Vgs (th) |Vgs (V) | is turned off, and the corresponding VSB is turned off.

When USB power supply is connected, VIN_5V is disconnected, the gate voltage of the NMOS tube Q5 is 0V, |Vgs|=0V < |Vgs (th) |, and therefore the NMOS tube Q5 is cut off, the gate voltage of the PMOS tube Q4 is 5V, the source voltage is 5V, |Vgs|=0V < |Vgs (th) |, the PMOS tube Q4 is cut off, the gate voltage of the PMOS tube Q1 is 0V, |Vgs|=5V > |Vgs (th) |, because the PMOS tube Q1 is turned on and VUSB starts to supply power, the gate voltage of the NMOS tube Q6 is 5V, |Vgs|=5V|Vgs (th) |, the NMOS tube Q6 is turned on, the gate voltage of the PMOS tube Q3 is 0V, |Vgs|=5V > |Vgs (th) |, the PMOS tube Q3 is turned on, the output is the main power supply, the gate voltage of the PMOS tube Q2 is 5V, and the source voltage is 5 V|Vss|Vss|5Vgs|Vgs (th) |0 Vg|Vg (th) | is turned off;

When the battery is powered, VIN_5V is disconnected, VUSB is disconnected, the gate voltage of the NMOS tube Q5 is 0V, |Vgs|=0V < |Vgs (th) |, and thus the NMOS tube Q5 is cut off, the gate voltage of the PMOS tube Q4 is 0V, the source voltage is 0V, |Vgs|=0V < |Vgs (th) |, and thus the PMOS tube Q4 is cut off, the gate voltage of the PMOS tube Q1 is 0V, the source voltage is 0V, |Vgs|=0V < |Vgs (th) |, and thus the PMOS tube Q1 is cut off, the gate voltage of the NMOS tube Q6 is 0V, |=0V < |Vgs (th) |, and thus the NMOS tube Q6 is cut off, the gate voltage of the PMOS tube Q3 is 5V, the source voltage is 5V, |Vgs|=0V < |Vgs (th) |Vgs), and thus the NMOS tube Q3 is cut off, and the gate voltage of the PMOS tube Q2 is 0 V|Vgs|=0V|Vgs (th) |Vgs|Vgs (th) | and thus the power supply is turned on.

The 12V switch 22 in the multi-power switching circuit provided in this embodiment, as shown in fig. 4, includes a first 12V switch 221 and a second 12V switch 222, where the input end 21 of the 12V adapter is connected to the first 12V switch 221 and the second 12V switch 222, respectively, the output end of the boost module 4 is connected to the second 12V switch 222, and the first 12V switch 221 and the second 12V switch 222 are connected to the output ends of the two paths 12V input power switching modules, respectively.

In this embodiment, the first 12V switch corresponds to the 12V adapter input, and the second 12V switch corresponds to the output of the boost module, i.e., the 5V to 12V output.

When the power supply of the 12V adapter is connected, the first 5V switching switch is turned on, and correspondingly, the second 12V switching switch is turned off, the output power supply line of the boosting module is cut off, and the 12V adapter power supply line is selected as a main power supply line of the equipment.

When the 12V adapter power supply is not connected, but the 12V voltage requirement exists in the equipment, the output power supply of the boosting module, namely boosting 12V power supply, is used, at the moment, the first 5V change-over switch is turned off to cut off the 12V adapter power supply line, the second 12V change-over switch is turned on, and the output power supply line of the boosting module is selected as the main power supply line of the equipment.

In some embodiments, as shown in FIG. 5, the first 12V switch 221 includes an NMOS transistor Q9 and a PMOS transistor Q8, and the second 12V switch 222 includes a PMOS transistor Q7;

The input end of the 12V adapter (namely VIN_12V in fig. 5) is respectively connected with the grid electrode of the NMOS tube Q9, the drain electrode of the PMOS tube Q8 and the grid electrode of the PMOS tube Q7, the source electrode of the NMOS tube Q9 is grounded, the drain electrode is connected with the grid electrode of the PMOS tube Q8, the source electrode of the PMOS tube Q8 is respectively connected with the grid electrode of the PMOS tube Q8 and the output ends (namely VOUT_12V in fig. 5) of the two paths of 12V input power supply switching modules, the grid electrode of the PMOS tube Q7 is grounded, the source electrode is connected with the output ends (namely VOUT_12V in fig. 5) of the two paths of 12V input power supply switching modules, and the drain electrode is connected with the output end (namely VDC_12V in fig. 5) of the boosting module.

Preferably, the PMOS transistor in the above embodiment has the model AO3407A, vds= -30v, vgs= ±20v, vgs (th) = -1.8v, id= -4.2a, and the nmos transistor has the model AO3404A, vds=30v, vgs= ±20v, vgs (th) = 1.9v, id=5.8a.

Based on the circuit structure of the two-path 12V input power supply switching module, the switching working principle of the three-path 5V input power supply is as follows:

When the 12V adapter is connected, VIN_12V is 12V, the grid voltage of the NMOS tube Q9 is 12V, |Vgs|=12V > |Vgs (th) |, so that the NMOS tube Q9 is conducted, the grid voltage of the PMOS tube Q8 is 0V, |Vgs|=12V > |Vgs (th) |, so that the PMOS tube Q8 is conducted, VIN_12V is output for supplying power to a main power supply, the grid voltage of the PMOS tube Q7 is 12V, the source voltage is 12V, |Vgs|=0V < |Vgs (th) |, so that the PMOS tube Q7 is turned off, and VDC_12V is turned off for supplying power;

When power is supplied by the boost 12V, the VIN_12V is disconnected, the VIN_12V voltage is 0V, the grid voltage of the NMOS tube Q9 is 0V, |Vgs|=0V < |Vgs (th) |, the NMOS tube Q9 is cut off, the grid voltage of the PMOS tube Q8 is 12V, the source voltage is 12V, |Vgs|=0V < |Vgs (th) |, the PMOS tube Q8 is cut off, the grid voltage of the PMOS tube Q7 is 0V, the source voltage is 12V, |Vgs|=12V > |Vgs (th) |, the PMOS tube Q7 is turned on, and the output VDC_12V is used for supplying power to a main power supply.

The circuit structure of the boost module in the multi-power supply switching circuit provided by the embodiment is shown in fig. 6, and mainly comprises a 5V to 12V chip U1, a resistor R7 and a diode D1, wherein the enabling end of the chip U1 is connected with the output end of the three-path 5V input power supply switching module (i.e., vout_5v in fig. 6) through the resistor R7, and is automatically enabled to work, and the output end of the chip U1 is connected with the output end of the boost module through the diode D1.

In some specific embodiments, the 5V to 12V chip U1 is an asynchronous boost DC/DC converter chip preferably using a Bei Ling BL8042C scheme, and the resistance value of the resistor R7 is 100K. Accordingly, the output voltage vdc_12v of the boosting module has a calculation formula of vdc_12v=vref (1+r6/R8), wherein vref=0.6V, and vdc_12v=0.6 (1+100k/5.1K) =12.3V.

The circuit structure of the step-down module in the multi-power switching circuit provided in this embodiment is shown in fig. 7. The buck module preferably adopts a Mingda MD7218A50 LDO scheme, the highest input voltage is 15V, the maximum output current is 1A, and the direct current input voltage of 6-15V can be converted into constant 5V output.

The third embodiment of the utility model is as follows:

The embodiment is further developed based on the first embodiment or the second embodiment, and provides an electronic device. The electronic device includes the multi-power switching circuit described in the first or second embodiments. The specific structure of the multi-power switching circuit is not repeated here, and the details of the multi-power switching circuit are described in embodiment one or embodiment two.

The electronic equipment provided by the embodiment is provided with the multi-power supply switching circuit provided by the first embodiment or the second embodiment, so that the optimal power supply circuit can be automatically switched to supply power to the equipment according to the type of the power supply to which the equipment is connected, reasonable distribution and utilization of the power supply are realized, in addition, the mutual conversion between the 5V power supply and the 12V power supply can be realized, the equipment can work normally without being limited by the voltage of the connected power supply, complicated wiring and the trouble of being incapable of being matched are avoided, and the electronic equipment is more convenient for users to use.

The foregoing description is only illustrative of the present utility model and is not intended to limit the scope of the utility model, and all equivalent changes made by the specification and drawings of the present utility model, or direct or indirect application in the relevant art, are included in the scope of the present utility model.

Claims

1. The multi-power supply switching circuit is characterized by comprising three paths of 5V input power supply switching modules, two paths of 12V input power supply switching modules, a buck module and a boost module;

2. The multi-power switching circuit according to claim 1, wherein the output terminals of the three-way 5V input power switching module and the output terminals of the two-way 12V input power switching module are respectively connected with power supply output terminals.

3. The multi-power switching circuit of claim 1 wherein the 5V switch comprises a first 5V switch, a second 5V switch, a third 5V switch, and a fourth 5V switch, wherein the 5V adapter power input is connected to the fourth 5V switch through the first 5V switch, wherein the USB power input is connected to the fourth 5V switch through the second 5V switch, wherein the battery power input is connected to the fourth 5V switch through the third 5V switch, and wherein the fourth 5V switch is connected to the output of the three-way 5V input power switching module.

4. The multi-power supply switching circuit according to claim 3, wherein the first 5V switch comprises a PMOS tube Q4 and an NMOS tube Q5, the second 5V switch comprises a PMOS tube Q1, the third 5V switch comprises a PMOS tube Q2, and the fourth 5V switch comprises a PMOS tube Q3 and an NMOS tube Q6;

5. The multi-power supply switching circuit according to claim 1, wherein the 12V switching switch comprises a first 12V switching switch and a second 12V switching switch, wherein the input end of the 12V adapter is connected with the first 12V switching switch and the second 12V switching switch respectively, the output end of the boosting module is connected with the second 12V switching switch, and the first 12V switching switch and the second 12V switching switch are connected with the output ends of the two paths of 12V input power supply switching modules respectively.

6. The multi-power switching circuit of claim 5, wherein the first 12V switch comprises an NMOS transistor Q9 and a PMOS transistor Q8, and the second 12V switch comprises a PMOS transistor Q7;

7. The multi-power switching circuit according to claim 1, wherein the boost module comprises a 5V to 12V chip U1, a resistor R7 and a diode D1, wherein an enable end of the chip U1 is connected with an output end of the three-way 5V input power switching module through the resistor R7, and an output end of the chip U1 is connected with an output end of the boost module through the diode D1.

8. The multi-power switching circuit of claim 7 wherein the die U1 is an asynchronous boost DC/DC converter die.

9. The multi-power switching circuit of claim 1, wherein the buck module is an LDO regulator.

10. An electronic device comprising a multi-power switching circuit as claimed in any one of claims 1 to 9.