Multi-power switching circuit and electronic equipment

Abstract

The utility model provides a multi-power-supply switching circuit and electronic equipment. The multi-power-supply switching circuit comprises a three-path 5V input power supply switching module, a two-path 12V input power supply switching module, a step-down module and a step-up module, the three-path 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 change-over switch; the two-path 12V input power supply switching module comprises a 12V adapter input end and a 12V change-over 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 change-over switch; the output end of the 5V change-over switch is connected with the input end of the boosting module; the output end of the boost module and the input end of the 12V adapter are respectively connected with the input end of the step-down module through the 12V change-over switch; the output end of the voltage reduction module is connected with the power supply input end of the 5V adapter. Reasonable power distribution and utilization can be realized, and convenience is brought to users.

Description

Technical Field

[0001] The utility model relates to the technical field of power supplies, in particular to a multi-power supply switching circuit and electronic equipment. Background Art

[0002] Most existing electronic devices are equipped with multiple power interfaces. Conventional low-voltage electronic devices are equipped with power interfaces such as 5V and 12V. Some are also equipped with internal batteries, and some are also equipped with power interfaces such as USB interfaces. To ensure the safety of the internal circuit modules of the device, some restrictions are usually added to the above power interfaces, such as not being able to turn on the device while charging, and the 5V data port must be connected to a 12V power supply for normal operation. This leads to certain inconveniences during use. In addition, the power supply priority allocation of some electronic devices is not very reasonable. For example, the battery is still participating in the power supply when the adapter or computer USB is powered, which will reduce the battery life.

[0003] Therefore, in order to make it more convenient for customers to use electronic devices and effectively prevent the risk of incorrect power supply, it is necessary to perform reasonable automatic power switching and distribution on the power supply system of electronic devices. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a multi-power switching circuit and electronic equipment, which can automatically switch to use the optimal power supply line to power the equipment, thereby realizing the reasonable distribution and utilization of power and making it convenient for users to use the electronic equipment.

[0005] In order to solve the above technical problems, the first technical solution adopted by the present invention is:

[0006] A multi-power switching circuit, comprising: three 5V input power switching modules, two 12V input power switching modules, a step-down module and a step-up module;

[0007] The three-way 5V input power switching module includes a battery power input, a USB power input, a 5V adapter power input and a 5V switching switch; the two-way 12V input power switching module includes a 12V adapter input and a 12V switching switch; the battery power input, USB power input and 5V adapter power input are respectively connected to the input of the 5V switching switch; the output of the 5V switching switch is connected to the input of the boost module; the output of the boost module and the 12V adapter input are respectively connected to the input of the step-down module via the 12V switching switch; the output of the step-down module is connected to the 5V adapter power input.

[0008] Optionally, the output end of the three-way 5V input power switching module and the output end of the two-way 12V input power switching module are respectively connected to the power supply output end.

[0009] Optionally, the 5V switching switch includes a first 5V switching switch, a second 5V switching switch, a third 5V switching switch and a fourth 5V switching switch; the 5V adapter power supply input end is connected to the fourth 5V switching switch through the first 5V switching switch; the USB power supply input end is connected to the fourth 5V switching switch through the second 5V switching switch; the battery power supply input end is connected to the fourth 5V switching switch through the third 5V switching switch; the fourth 5V switching switch is connected to the output end of the three-way 5V input power switching module.

[0010] Optionally, the first 5V switch includes a PMOS transistor Q4 and an NMOS transistor Q5; the second 5V switch includes a PMOS transistor Q1; the third 5V switch includes a PMOS transistor Q2; and the fourth 5V switch includes a PMOS transistor Q3 and an NMOS transistor Q6;

[0011] The 5V adapter power supply input is respectively connected to the gate of the PMOS transistor Q1, the drain of the PMOS transistor Q4, and the gate of the NMOS transistor Q5; the gate of the PMOS transistor Q1 is also grounded, and the drain is connected to the USB power supply input; the gate of the PMOS transistor Q4 is connected to the drain of the NMOS transistor Q5; the source of the NMOS transistor Q5 is grounded; the source of the PMOS transistor Q4 is divided into three paths, one path is connected to the source of the PMOS transistor Q1, one path is connected to its own gate, and one path is respectively connected to the drain of the PMOS transistor Q3, the gate of the NMOS transistor Q6, and the gate of the PMOS transistor Q2; the source of the NMOS transistor Q6 is grounded, and the drain is respectively connected to the gate of the PMOS transistor Q3 and the output of the three-way 5V input power switching module; the gate and drain of the PMOS transistor Q3 are connected to the output of the three-way 5V input power switching module; the drain of the PMOS transistor Q2 is connected to the battery power supply input, and the source is connected to the output of the three-way 5V input power switching module.

[0012] Optionally, the 12V switching switch includes a first 12V switching switch and a second 12V switching switch; the 12V adapter input end is respectively connected to the first 12V switching switch and the second 12V switching switch; the output end of the boost module is connected to the second 12V switching switch; the first 12V switching switch and the second 12V switching switch are respectively connected to the output ends of the two 12V input power switching modules.

[0013] Optionally, the first 12V switch includes an NMOS transistor Q9 and a PMOS transistor Q8; the second 12V switch includes a PMOS transistor Q7;

[0014] The 12V adapter input end is respectively connected to the gate of the NMOS tube Q9, the drain of the PMOS tube Q8, and the gate of the PMOS tube Q7; the source of the NMOS tube Q9 is connected to the ground, and the drain is connected to the gate of the PMOS tube Q8; the source of the PMOS tube Q8 is respectively connected to its own gate and the output end of the two-way 12V input power switching module; the gate of the PMOS tube Q7 is grounded, the source is connected to the output end of the two-way 12V input power switching module, and the drain is connected to the output end of the boost module.

[0015] Optionally, the boost module includes a 5V to 12V chip U1, a resistor R7 and a diode D1; the enable end of the chip U1 is connected to the output end of the three-way 5V input power switching module through the resistor R7; the output end of the chip U1 is connected to the output end of the boost module via the diode D1.

[0016] Optionally, the chip U1 is an asynchronous boost DC / DC converter chip.

[0017] Optionally, the step-down module is an LDO regulator.

[0018] The second technical solution provided by the utility model is:

[0019] An electronic device comprises the above-mentioned multi-power switching circuit.

[0020] The beneficial effects of the present invention are as follows: the multi-power switching circuit provided by the present invention can automatically switch to use the optimal power supply line to power the equipment according to the type of power currently connected, thereby realizing the reasonable distribution and utilization of power; in addition, it can also realize the mutual conversion between 5V and 12V power supplies, so that the equipment can work normally without being restricted by the power supply voltage connected, eliminating the trouble of cumbersome wiring and inability to adapt, and is more convenient for users to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of the basic components of a multi-power switching circuit provided in Example 1 of the present utility model;

[0022] Figure 2 A schematic diagram of the composition of a 5V switch in a multi-power switching circuit provided in Example 2 of the present utility model;

[0023] Figure 3 This is a schematic diagram of the circuit structure of a 5V switch in a specific embodiment of the present utility model;

[0024] Figure 4 A schematic diagram of the composition of a 12V switch in a multi-power switching circuit provided in Example 2 of the present utility model;

[0025] Figure 5 This is a schematic diagram of the circuit structure of a 12V switch in a specific embodiment of the present utility model;

[0026] Figure 6 A schematic diagram of the composition of a boost module in a multi-power switching circuit provided in the second embodiment of the present utility model;

[0027] Figure 7 This is a schematic diagram of the composition of the buck module in the multi-power switching circuit provided in the second embodiment of the present utility model.

[0028] Description of labels:

[0029] 1. Three-way 5V input power switching module; 2. Two-way 12V input power switching module;

[0030] 3. Buck module; 4. Boost module; 5. Power supply output terminal;

[0031] 11. Battery power input terminal, 12. USB power input terminal; 13. 5V adapter power input terminal;

[0032] 14. 5V switch;

[0033] 141, first 5V switch; 142, second 5V switch; 143, third 5V switch; 144, fourth 5V switch;

[0034] 21. 12V adapter input terminal; 22. 12V switch;

[0035] 221. First 12V switch; 222. Second 12V switch. DETAILED DESCRIPTION

[0036] In order to explain in detail the possible application scenarios, technical principles, specific solutions that can be implemented, and the purpose and effects of the present invention, the following is a detailed description of the specific embodiments listed in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of the present invention and are therefore only examples and are not intended to limit the scope of protection of the present invention.

[0037] References to "embodiments" herein mean that the specific features, structures, or characteristics described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the word "embodiment" in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or relevance to other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the various technical features mentioned in the embodiments can be combined in any manner to form a corresponding implementable technical solution.

[0038] Unless otherwise defined, the technical terms used herein have the same meanings as those generally understood by those skilled in the art to which the present invention belongs; the use of relevant terms herein is only for describing specific embodiments and is not intended to limit the present application.

[0039] In the description of this utility model, the term "and / or" is used to describe a logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and both A and B exist. In addition, the character " / " in this document generally indicates that the objects before and after are in a logical "or" relationship.

[0040] In the present invention, terms such as "first" and "second" are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship of quantity, priority or sequence between these entities or operations.

[0041] Without further restrictions, in the present invention, the words "include", "comprise", "have" or other similar expressions used in sentences are intended to cover non-exclusive inclusion. These expressions do not exclude the presence of additional elements in the process, method or product including the elements, so that the process, method or product including a series of elements may include not only those limited elements, but also other elements not explicitly listed, or also include elements inherent to such process, method or product.

[0042] Consistent with the understanding in the Examination Guidelines, in this utility model, expressions such as "greater than," "less than," and "exceed" are understood to exclude the number itself; expressions such as "above," "below," and "within" are understood to include the number itself. Furthermore, in the description of the embodiments of this utility model, "multiple" means two or more (including two), and similar expressions related to "multiple," such as "multiple groups" and "multiple times," are also understood in this manner, unless otherwise specifically defined.

[0043] In the description of the embodiments of the present invention, the space-related expressions used, such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or position relationship based on the orientation or position relationship shown in the specific embodiments or drawings, and are only for the convenience of describing the specific embodiments of the present invention or facilitating the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, it should not be understood as a limitation on the embodiments of the present invention.

[0044] Unless otherwise expressly specified or limited, in the description of the embodiments of the present invention, the terms "installed", "connected", "connected", "fixed", "set", etc. used should be understood in a broad sense. For example, the "connection" can be a fixed connection, a detachable connection, or an integrated setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For those skilled in the technical field of the present invention, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0045] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following description is given in conjunction with the embodiments and the accompanying drawings.

[0046] Please refer to Figure 1 , the first embodiment of the present utility model is:

[0047] This embodiment provides a multi-power switching circuit, such as Figure 1 As shown, it includes three 5V input power switching modules 1, two 12V input power switching modules 2, a step-down module 3 and a step-up module 4;

[0048] The three-way 5V input power switching module includes a battery power input terminal, a USB power input terminal, a 5V adapter power input terminal and a 5V switching switch; the two-way 12V input power switching module 2 includes a 12V adapter input terminal 21 and a 12V switching switch 22; the battery power input terminal 11, the USB power input terminal 12 and the 5V adapter power input terminal 13 are respectively connected to the input terminal of the 5V switching switch 14; the output terminal of the 5V switching switch 14 is connected to the input terminal of the boost module 4; the output terminal of the boost module 4 and the 12V adapter input terminal 21 are respectively connected to the input terminal of the step-down module 3 via the 12V switching switch 22; the output terminal of the step-down module 3 is connected to the 5V adapter power input terminal 13.

[0049] The output ends of the three-way 5V input power switching module 1 and the output ends of the two-way 12V input power switching module 2 are respectively connected to the power supply output end 5. The power supply output end 5 is the main power input end of the electronic device, which supplies power to the electronic device.

[0050] In this embodiment, the three-way 5V input power switching module can automatically switch to the optimal power supply line as the power supply for electronic devices by controlling the shutdown and conduction of the corresponding power supply lines according to the preset priority for three conventional 5V power inputs (battery power supply, USB power supply and 5V adapter).

[0051] Among them, the priorities are from high to low: 5V adapter power supply, USB power supply, and battery power supply. The basis for setting the priorities is: the battery is a consumable device and the power supply time is limited. When there is USB power supply or 5V adapter power supply, it is best not to use the battery power supply circuit; the USB interface is moderately fragile, but it is often connected to a computer or power bank and other devices for power supply. The stability and continuity of the power supply are not as good as the 5V adapter power supply. Therefore, when there is a 5V adapter power supply, it is best not to use the functional USB power supply and battery power supply circuit. It can be seen that the automatic switching priority of the power supply circuit set for the three-way 5V input power switching module in this embodiment is set according to the durability and power supply stability of the three 5V power inputs, which is reasonable; the automatic switching of the three-way 5V input power supply achieved based on this is also reasonable, and can achieve reasonable distribution and use of power.

[0052] In this embodiment, the two-way 12V input power switching module can, for the two-way 12V input power supply situation (12V adapter power supply and 5V to 12V power supply), control the corresponding power supply lines to be turned off and on according to the preset priority, so as to automatically switch to use the optimal power supply line as the power supply for the electronic device.

[0053] The priority is that 12V adapter power supply takes precedence over 5V to 12V power supply. The priority is set based on the fact that boosting 5V to 12V will result in a certain efficiency loss. When a 12V adapter is used for power supply, it is best not to use 5V boost power supply.

[0054] In this embodiment, the step-down module, in the event that a 12V power input is present but a 5V power input is not available, causing some circuits requiring 5V power to malfunction, steps down the 12V power input to 5V to power the circuits requiring 5V power. The step-down module's input is connected to the output of the two 12V input power switching modules to obtain the 12V power input.

[0055] In this embodiment, the boost module, when a 5V power input is available but a 12V power input is not available, causes some circuits requiring 12V power to malfunction. By boosting the 5V power input to 12V, the boost module can power the circuits requiring 12V power. The input of the step-down module is connected to the output of the three-way 5V input power switching module to obtain the 5V power input.

[0056] The multi-power switching circuit provided in this embodiment can, on the one hand, automatically switch to the optimal power supply line to power the device based on the currently connected power source type, thereby achieving reasonable power distribution and utilization. Specifically, when a 5V power source is connected, the 5V adapter is the primary power source, followed by USB power, and then battery power. When a 12V power source is connected, the 12V adapter is the primary power source, followed by 5V to 12V power.

[0057] On the other hand, it can also realize the mutual conversion between 5V and 12V power supply, so that the equipment can work normally regardless of the connected power supply voltage, eliminating the trouble of tedious wiring and adaptation, and more convenient for users. That is, when there is no 5V power supply, it can convert 12V to 5V power supply; when there is no 12V power supply, it can convert 5V to 12V power supply.

[0058] Please refer to Figures 2 to 7 , the second embodiment of the present utility model is:

[0059] The present invention is further expanded based on the first embodiment, and each internal module is specifically refined.

[0060] The 5V switch in the multi-power switching circuit provided in this embodiment is as follows: Figure 2As shown, it includes a first 5V switch 141, a second 5V switch 142, a third 5V switch 143 and a fourth 5V switch 144; the 5V adapter power input terminal 13 is connected to the fourth 5V switch 144 through the first 5V switch 141; the USB power input terminal 12 is connected to the fourth 5V switch 144 through the second 5V switch 142; the battery power input terminal 11 is connected to the fourth 5V switch 144 through the third 5V switch 143; the fourth 5V switch 144 is connected to the output terminal of the three-way 5V input power switching module.

[0061] 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.

[0062] Here, when the 5V adapter power supply is connected, the first 5V switch will be turned on; accordingly, the second 5V switch and the third 5V switch will be turned off, cutting off the USB power supply line and the battery power supply line; the fourth 5V switch will be turned on, selecting the 5V adapter power supply line as the main power supply line of the device.

[0063] When the USB power supply is connected, the second 5V switch is turned on; accordingly, the first 5V switch and the third 5V switch are turned off, cutting off the 5V adapter power supply line and the battery power supply line; the fourth 5V switch is turned on, selecting the USB power supply line as the main power supply line of the device.

[0064] When the battery is powered, the third 5V switch is turned on; accordingly, the first 5V switch and the second 5V switch are turned off, and at the same time the fourth 5V switch is turned off, cutting off the 5V adapter power supply line and the USB power supply line, and selecting the battery power supply line as the main power supply line of the device.

[0065] In some embodiments, such as Figure 3 As shown, 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; the fourth 5V switch 144 includes a PMOS transistor Q3 and an NMOS transistor Q6;

[0066] Among them, the 5V adapter power supply input terminal (ie Figure 3The VIN_5V in the circuit is connected to the gate of the PMOS tube Q1, the drain of the PMOS tube Q4 and the gate of the NMOS tube Q5 respectively; the gate of the PMOS tube Q1 is also grounded, and the drain is connected to the USB power supply input terminal (i.e. Figure 3 The gate of the PMOS tube Q4 is connected to the drain of the NMOS tube Q5; the source of the NMOS tube Q5 is grounded; the source of the PMOS tube Q4 is divided into three paths, one path is connected to the source of the PMOS tube Q1, one path is connected to its own gate, and one path is respectively connected to the drain of the PMOS tube Q3, the gate of the NMOS tube Q6 and the gate of the PMOS tube Q2; the source of the NMOS tube Q6 is grounded, and the drain is respectively connected to the gate of the PMOS tube Q3 and the output end of the three 5V input power switching modules (i.e. Figure 3 The gate and drain of the PMOS tube Q3 are connected to the output end of the three-way 5V input power switching module (ie Figure 3 The drain of the PMOS tube Q2 is connected to the battery power input terminal (i.e. Figure 3 The source is connected to the output end of the three-way 5V input power switching module (i.e. Figure 3 VOUT_5V) connection in the .

[0067] Preferably, the PMOS tube model in the above specific embodiment is SM2313, Vds=-20V, Vgs=±12V, Vgs(th)=-1.0V, Id=-4.2A; the NMOS tube model is SM2300, Vds=20V, Vgs=±12V, Vgs(th)=1.0V, Id=5.1A.

[0068] Based on the circuit structure of the three-way 5V input power switching module, the switching working principle of the three-way 5V input power is as follows:

[0069] When a 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 the NMOS tube Q5 is turned on; the gate voltage of the PMOS tube Q4 is 0V, |Vgs|=5V>|Vgs(th)|, so the PMOS tube Q4 is turned on; the gate voltage of the PMOS tube Q1 is 5V, the source voltage is 5V, |Vgs|=0V<|Vgs(th)|, so the PMOS tube Q1 is turned off, and the corresponding VU SB disconnects the power supply, and the gate voltage of NMOS transistor Q6 is 5V, |Vgs|=5V>|Vgs(th)|, so NMOS transistor Q6 is turned on; the gate voltage of PMOS transistor Q3 is 0V, |Vgs|=5V>|Vgs(th)|, so PMOS transistor Q3 is turned on and outputs VIN_5V as the main power supply; the gate voltage of PMOS transistor Q2 is 5V, and the source voltage is 5V, |Vgs|=0V<|Vgs(th)|, so PMOS transistor Q2 is turned off, and VBAT disconnects the power supply.

[0070] When the USB power supply is connected, VIN_5V is disconnected, the gate voltage of NMOS tube Q5 is 0V, |Vgs|=0V<|Vgs(th)|, so NMOS tube Q5 is turned off; the gate voltage of PMOS tube Q4 is 5V, the source voltage is 5V, |Vgs|=0V<|Vgs(th)|, PMOS tube Q4 is turned off; the gate voltage of PMOS tube Q1 is 0V, |Vgs|=5V>|Vgs(th|, because PMOS tube Q1 is turned on, VUSB starts Power supply; the gate voltage of NMOS tube Q6 is 5V, |Vgs|=5V>|Vgs(th)|, NMOS tube Q6 is turned on; the gate voltage of PMOS tube Q3 is 0V, |Vgs|=5V>|Vgs(th)|, PMOS tube Q3 is turned on; the output VUSB output is the main power supply; the gate voltage of PMOS tube Q2 is 5V, the source voltage is 5V, |Vgs|=0V<|Vgs(th)|, so PMOS tube Q2 is turned off and VBAT is disconnected from the power supply;

[0071] When powered by the battery, VIN_5V is disconnected, VUSB is disconnected, the gate voltage of NMOS tube Q5 is 0V, |Vgs|=0V<|Vgs(th)|, so NMOS tube Q5 is turned off; the gate voltage of PMOS tube Q4 is 0V, the source voltage is 0V, |Vgs|=0V<|Vgs(th)|, so PMOS tube Q4 is turned off; the gate voltage of PMOS tube Q1 is 0V, the source voltage is 0V, |Vgs|=0V<|Vgs(th)|, so The PMOS transistor Q1 is turned off; the gate voltage of the NMOS transistor Q6 is 0V, |Vgs|=0V<|Vgs(th)|, so the NMOS transistor Q6 is turned off; the gate voltage of the PMOS transistor Q3 is 5V, and the source voltage is 5V, |Vgs|=0V<|Vgs(th)|, so the NMOS transistor Q3 is turned off; the gate voltage of the PMOS transistor Q2 is 0V, |Vgs|=5V>|Vgs(th)|, so the PMOS transistor Q2 is turned on, outputting VBAT to supply power to the main power supply.

[0072] The 12V switch 22 in the multi-power switching circuit provided in this embodiment is as follows: Figure 4 As shown, it includes a first 12V switching switch 221 and a second 12V switching switch 222; the 12V adapter input end 21 is respectively connected to the first 12V switching switch 221 and the second 12V switching switch 222; the output end of the boost module 4 is connected to the second 12V switching switch 222; the first 12V switching switch 221 and the second 12V switching switch 222 are respectively connected to the output ends of the two 12V input power switching modules.

[0073] In this embodiment, the first 12V switch corresponds to the 12V adapter input; the second 12V switch corresponds to the output end of the boost module, that is, 5V to 12V output.

[0074] Here, when the 12V adapter power supply is connected, the first 5V switch will be turned on; accordingly, the second 12V switch will be turned off, cutting off the output power supply line of the boost module and selecting the 12V adapter power supply line as the main power supply line of the device.

[0075] When the 12V adapter is not connected for power supply, but there is a 12V voltage requirement in the device, the output of the boost module is used for power supply, i.e., the boosted 12V power supply. At this time, the first 5V switch will be turned off to cut off the 12V adapter power supply line, and the second 12V switch will be turned on, selecting the output power supply line of the boost module as the main power supply line of the device.

[0076] In some embodiments, such as Figure 5As shown, the first 12V switch 221 includes an NMOS transistor Q9 and a PMOS transistor Q8; the second 12V switch 222 includes a PMOS transistor Q7;

[0077] The 12V adapter input terminal (i.e. Figure 5 The VIN_12V in the circuit is connected to the gate of the NMOS transistor Q9, the drain of the PMOS transistor Q8, and the gate of the PMOS transistor Q7 respectively; the source of the NMOS transistor Q9 is grounded, and the drain is connected to the gate of the PMOS transistor Q8; the source of the PMOS transistor Q8 is connected to its own gate and the output end of the two 12V input power switching modules (i.e. Figure 5 The gate of the PMOS tube Q7 is grounded, and the source is connected to the output end of the two 12V input power switching modules (i.e. Figure 5 The drain is connected to the output end of the boost module (i.e. Figure 5 VDC_12V) connection in the .

[0078] Preferably, the PMOS tube model in the above specific embodiment is AO3407A, Vds=-30V, Vgs=±20V, Vgs(th)=-1.8V, Id=-4.2A; the NMOS tube model is AO3404A, Vds=30V, Vgs=±20V, Vgs(th)=1.9V, Id=5.8A.

[0079] Based on the circuit structure of the two-way 12V input power switching module, the switching principle of the three-way 5V input power is as follows:

[0080] When a 12V adapter is connected, the VIN_12V voltage is 12V, the gate voltage of the NMOS transistor Q9 is 12V, |Vgs| = 12V > |Vgs(th)|, and thus the NMOS transistor Q9 is turned on. The gate voltage of the PMOS transistor Q8 is 0V, |Vgs| = 12V > |Vgs(th)|, and thus the PMOS transistor Q8 is turned on and outputs VIN_12V as the main power supply. The gate voltage of the PMOS transistor Q7 is 12V, and the source voltage is 12V, |Vgs| = 0V < |Vgs(th)|, so the PMOS transistor Q7 is turned off, and the VDC_12V power supply is disconnected.

[0081] When powered by the boosted 12V voltage, VIN_12V is disconnected, the VIN_12V voltage is 0V, the gate voltage of the NMOS transistor Q9 is 0V, |Vgs|=0V<|Vgs(th)|, and the NMOS transistor Q9 is cut off; the gate voltage of the PMOS transistor Q8 is 12V, the source voltage is 12V, |Vgs|=0V<|Vgs(th)|, and the PMOS transistor Q8 is cut off; the gate voltage of the PMOS transistor Q7 is 0V, the source voltage is 12V, |Vgs|=12V>|Vgs(th)|, and the PMOS transistor Q7 is turned on, outputting VDC_12V to supply power to the main power supply.

[0082] The circuit structure of the boost module in the multi-power switching circuit provided in this embodiment is as follows: Figure 6 As shown, it mainly includes a 5V to 12V chip U1, a resistor R7 and a diode D1; the enable end of the chip U1 is connected to the output end of the three-way 5V input power switching module (i.e. Figure 6 The output end of the chip U1 is connected to the output end of the boost module via the diode D1.

[0083] In some specific embodiments, the 5V-to-12V converter chip U1 preferably uses the Belling BL8042C, an asynchronous step-up DC / DC converter chip. The resistor R7 has a value of 100K. Accordingly, the boost module's output voltage, VDC_12V, is calculated as follows: VDC_12V = VREF * (1 + R6 / R8). If VREF = 0.6V, then VDC_12V = 0.6 * (1 + 100K / 5.1K) = 12.3V.

[0084] The circuit structure of the step-down module in the multi-power switching circuit provided in this embodiment is as follows: Figure 7 The step-down module preferably uses the Mingda MD7218A50 LDO solution, which has a maximum input voltage of 15V and a maximum output current of 1A. It can convert a 6-15V DC input voltage into a constant 5V output.

[0085] The third embodiment of the present invention is:

[0086] This embodiment further expands upon the first or second embodiment and provides an electronic device. The electronic device includes the multi-power switching circuit described in the first or second embodiment. The specific structure of the multi-power switching circuit is not repeated here; for details, please refer to the description of the first or second embodiment.

[0087] The electronic device provided in this embodiment, since equipped with the multi-power switching circuit provided in the first or second embodiment, can automatically switch to use the optimal power supply line to power the device according to the type of power supply currently connected to the device, thereby realizing the reasonable distribution and utilization of power; in addition, it can also realize the mutual conversion between 5V and 12V power supplies, so that the device can operate normally without being restricted by the power supply voltage connected, eliminating the trouble of cumbersome wiring and adaptation, and is more convenient for users.

[0088] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A multi-power switching circuit, characterized in that: include: Three-way 5V input power switching module, two-way 12V input power switching module, buck module and boost module; The three-way 5V input power switching module includes a battery power input, a USB power input, a 5V adapter power input and a 5V switching switch; the two-way 12V input power switching module includes a 12V adapter input and a 12V switching switch; the battery power input, USB power input and 5V adapter power input are respectively connected to the input of the 5V switching switch; the output of the 5V switching switch is connected to the input of the boost module; the output of the boost module and the 12V adapter input are respectively connected to the input of the step-down module via the 12V switching switch; the output of the step-down module is connected to the 5V adapter power input.

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

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

4. The multi-power switching circuit according to claim 3, wherein: The first 5V switch includes a PMOS transistor Q4 and an NMOS transistor Q5; the second 5V switch includes a PMOS transistor Q1; the third 5V switch includes a PMOS transistor Q2; and the fourth 5V switch includes a PMOS transistor Q3 and an NMOS transistor Q6. The 5V adapter power supply input is respectively connected to the gate of the PMOS transistor Q1, the drain of the PMOS transistor Q4, and the gate of the NMOS transistor Q5; the gate of the PMOS transistor Q1 is also grounded, and the drain is connected to the USB power supply input; the gate of the PMOS transistor Q4 is connected to the drain of the NMOS transistor Q5; the source of the NMOS transistor Q5 is grounded; the source of the PMOS transistor Q4 is divided into three paths, one path is connected to the source of the PMOS transistor Q1, one path is connected to its own gate, and one path is respectively connected to the drain of the PMOS transistor Q3, the gate of the NMOS transistor Q6, and the gate of the PMOS transistor Q2; the source of the NMOS transistor Q6 is grounded, and the drain is respectively connected to the gate of the PMOS transistor Q3 and the output of the three-way 5V input power switching module; the gate and drain of the PMOS transistor Q3 are connected to the output of the three-way 5V input power switching module; the drain of the PMOS transistor Q2 is connected to the battery power supply input, and the source is connected to the output of the three-way 5V input power switching module.

5. The multi-power switching circuit according to claim 1, wherein: The 12V switching switch includes a first 12V switching switch and a second 12V switching switch; the input end of the 12V adapter is respectively connected to the first 12V switching switch and the second 12V switching switch; the output end of the boost module is connected to the second 12V switching switch; the first 12V switching switch and the second 12V switching switch are respectively connected to the output ends of the two 12V input power switching modules.

6. The multi-power switching circuit according to claim 5, wherein: The first 12V switch includes an NMOS transistor Q9 and a PMOS transistor Q8; the second 12V switch includes a PMOS transistor Q7; The 12V adapter input end is respectively connected to the gate of the NMOS tube Q9, the drain of the PMOS tube Q8, and the gate of the PMOS tube Q7; the source of the NMOS tube Q9 is connected to the ground, and the drain is connected to the gate of the PMOS tube Q8; the source of the PMOS tube Q8 is respectively connected to its own gate and the output end of the two-way 12V input power switching module; the gate of the PMOS tube Q7 is grounded, the source is connected to the output end of the two-way 12V input power switching module, and the drain is connected to the output end of the boost module.

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

8. The multi-power switching circuit according to claim 7, wherein: The chip U1 is an asynchronous boost DC / DC converter chip.

9. The multi-power switching circuit according to claim 1, wherein: The step-down module is an LDO voltage regulator.

10. An electronic device, characterized in that: The electronic device comprises the multi-power switching circuit according to any one of claims 1 to 9.

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