Dual power supply switching circuit and electronic device

Abstract

The utility model discloses a kind of dual power supply switching circuit and electronic equipment, and power supply switching is realized by two independent power supply circuits, first power supply circuit and second power supply circuit include control unit and switch unit respectively.Two power supply circuits are linked by first control unit and second control unit Control, can when first power is accessed, first switch unit is turned on to make that first power and the load of electronic equipment form passage, and second switch unit is disconnected to make that the passage of second power and the load of electronic equipment is disconnected, ensure that two power supplies are mutually exclusive power supply, so that two power supplies have and only one power supply, avoid the case that two power supplies simultaneously power supply or do not power supply, realize the stable switching of battery power supply and external power supply.

Description

Technical Field

[0001] This utility model relates to the field of power supply switching technology, and in particular to a dual-power supply switching circuit and electronic device. Background Technology

[0002] To meet the power supply needs of different usage scenarios, POS machines and other payment devices are typically equipped with multiple power supply channels. The first channel is equipped with battery power for normal operation in mobile or environments without external power. Meanwhile, to reduce battery consumption when used in fixed locations with external power, POS machines are also designed with a second power supply channel that connects to an external power source.

[0003] However, in related technologies, situations often arise where two power supply channels are powered simultaneously or neither is powered at all, affecting the normal operation of the power supply. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a dual power supply switching circuit and electronic device, which can avoid the situation where both power supplies are powered at the same time or neither is powered, and realize stable switching between battery power supply and external power supply.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0006] A dual-power supply switching circuit is used to switch power supply channels for electronic devices, wherein the power supply channels include a first power supply and a second power supply; the switching circuit includes a first power supply circuit and a second power supply circuit.

[0007] The first power supply circuit includes a first control unit and a first switching unit; the second power supply circuit includes a second control unit and a second switching unit.

[0008] The first power supply circuit is used to connect the first power source and the load of the electronic device to form a path; the second power supply circuit is used to connect the second power source and the load of the electronic device to form a path.

[0009] The first control unit is used to turn on the first switching unit when the first power supply is connected, so that the first power supply and the load of the electronic device form a path;

[0010] The second control unit is used to disconnect the second switching unit when the first power supply is connected, so as to disconnect the path between the second power supply and the load of the electronic device;

[0011] The second control unit is further configured to turn on the second switching unit when the first power supply is disconnected, so that the second power supply and the load of the electronic device form a path.

[0012] Furthermore, the first end of the first switching unit is used to connect to the first power supply, the second end of the first switching unit is used to connect to the load of the electronic device, and the control end of the first switching unit is connected to the first end of the first control unit.

[0013] The control terminal of the first control unit is used to connect to the first power supply, and the second terminal of the first control unit is grounded;

[0014] The first end of the second switching unit is used to connect to the second power supply, the second end of the second switching unit is used to connect to the load of the electronic device, and the control end of the second switching unit is connected to the first end of the second control unit;

[0015] The control terminal of the second control unit is used to connect to the first power supply, and the second terminal of the second control unit is grounded.

[0016] Furthermore, the first switching unit includes a first transistor and a second transistor;

[0017] The control electrode of the first transistor is connected to the control electrode of the second transistor, and the first main electrode of the first transistor is connected to the first main electrode of the second transistor.

[0018] The second main electrode of the first transistor is used to connect to the first power supply, and the second main electrode of the second transistor is used to connect to the load of the electronic device;

[0019] The control electrodes of the first transistor and the second transistor are connected to the first terminal of the first control unit.

[0020] Furthermore, the second switching unit includes a third transistor and a fourth transistor;

[0021] The control electrode of the third transistor is connected to the control electrode of the fourth transistor, and the first main electrode of the third transistor is connected to the first main electrode of the fourth transistor.

[0022] The second main electrode of the third transistor is used to connect to the second power supply, and the second main electrode of the fourth transistor is used to connect to the load of the electronic device;

[0023] The control electrodes of the third transistor and the fourth transistor are connected to the first terminal of the second control unit.

[0024] Furthermore, a controlled diode is disposed between the control electrode and the first main electrode of the first transistor, the second transistor, the third transistor, and the fourth transistor.

[0025] Furthermore, the first end of the first switching unit is used to connect to the first power supply, the second end of the first switching unit is used to connect to the load of the electronic device, and the control end of the first switching unit is connected to the first end of the first control unit.

[0026] The control terminal of the first control unit is used to connect to the processor of the electronic device, and the second terminal of the first control unit is grounded. When the first power supply is connected, the processor of the electronic device controls the first control unit to turn on the first switching unit.

[0027] The first end of the second switching unit is used to connect to the second power supply, the second end of the second switching unit is used to connect to the load of the electronic device, and the control end of the second switching unit is connected to the first end of the second control unit;

[0028] The control terminal of the second control unit is used to connect to the processor of the electronic device. The second terminal of the second control unit is grounded. When the first power supply is connected, the processor of the electronic device controls the second control unit to disconnect the second switching unit and when the first power supply is disconnected, it controls the second control unit to turn on the second switching unit.

[0029] Furthermore, both the first power supply circuit and the second power supply circuit include a protection unit;

[0030] The protection unit includes a protection capacitor and a protection resistor;

[0031] The first main electrode is connected to one end of the protection capacitor and one end of the protection resistor, respectively, and the control electrode is connected to the other end of the protection capacitor and the other end of the protection resistor, respectively.

[0032] Furthermore, the first control unit includes a fifth transistor;

[0033] The control electrode of the fifth transistor is used to connect to the first power supply;

[0034] The first main electrode of the fifth transistor is connected to the control electrodes of the first transistor and the second transistor, respectively.

[0035] The second main electrode of the fifth transistor is grounded.

[0036] Furthermore, the second control unit includes a sixth transistor and a seventh transistor;

[0037] The control electrode of the sixth transistor is used to connect to the first power supply;

[0038] The first main electrode of the sixth transistor is respectively connected to the control electrode of the seventh transistor, the first main electrodes of the third transistor and the fourth transistor;

[0039] The first main electrode of the seventh transistor is respectively connected to the control electrodes of the third transistor and the fourth transistor;

[0040] The second main electrodes of the sixth transistor and the seventh transistor are both grounded.

[0041] To solve the above technical problems, another technical solution adopted by the present utility model is:

[0042] An electronic device includes the above-mentioned dual-power-supply switching circuit.

[0043] The beneficial effects of the present utility model are as follows: The power supply switching is realized through two independent power supply circuits. The first power supply circuit and the second power supply circuit each include a control unit and a switching unit. In the first power supply circuit, when the first power supply is connected, the first control unit conducts the first switching unit, so that the first power supply forms a path with the load of the electronic device. In the second power supply circuit, when the first power supply is connected, the second control unit disconnects the second switching unit, so that the path between the second power supply and the load of the electronic device is disconnected, and when the first power supply is disconnected, the second control unit conducts the second switching unit, so that the second power supply forms a path with the load of the electronic device. Based on this, the two power supply circuits are联动 controlled by the first control unit and the second control unit based on the same power supply, and can disconnect the power supply path of the other power supply when one power supply is connected, and conduct the power supply path of the other power supply when one power supply is disconnected, ensuring that the two power supplies supply power mutually exclusively, so that only one of the two power supplies supplies power, avoiding the situation of simultaneous power supply or no power supply of the two power supplies, and realizing the stable switching between battery power supply and external power supply. Description of the Drawings

[0044] Figure 1 It is a schematic structural diagram of a dual-power-supply switching circuit provided by an embodiment of the present utility model;

[0045] Figure 2 It is a schematic structural diagram of a dual-power-supply switching circuit controlled by the first power supply provided by an embodiment of the present utility model;

[0046] Figure 3 It is a circuit structure diagram of a first power supply circuit provided by an embodiment of the present utility model;

[0047] Figure 4 It is a circuit structure diagram of a second power supply circuit provided by an embodiment of the present utility model;

[0048] Figure 5 A schematic diagram of a dual-power supply switching circuit controlled by a processor of an electronic device, provided for an embodiment of this utility model;

[0049] Label Explanation:

[0050] 10. First power supply circuit; 20. Second power supply circuit; 30. Protection unit; 101. First control unit; 102. First switching unit; 201. Second control unit; 202. Second switching unit. Detailed Implementation

[0051] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0052] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0053] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0054] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0055] In related technologies, situations often arise where two power supply channels supply power simultaneously or neither supplies power at all, affecting the normal operation of the power supply. For example, when a POS machine is connected to an external power source, the battery and the external power source often supply power to the POS machine simultaneously. This power supply method causes the battery to be consumed even when connected to an external power source, which not only fails to effectively extend battery life but may also increase the risk of battery damage.

[0056] To solve the above-mentioned technical problems, this utility model provides a dual-power supply switching circuit for switching power supply channels for electronic devices. The power supply channels include a first power supply and a second power supply; the switching circuit includes a first power supply circuit and a second power supply circuit.

[0057] The first power supply circuit includes a first control unit and a first switching unit; the second power supply circuit includes a second control unit and a second switching unit.

[0058] The first power supply circuit is used to connect the first power supply and the load of the electronic device so that the first power supply and the load of the electronic device form a path; the second power supply circuit is used to connect the second power supply and the load of the electronic device so that the second power supply and the load of the electronic device form a path.

[0059] The first control unit is used to turn on the first switching unit when the first power supply is connected, so that the first power supply and the load of the electronic device form a path;

[0060] The second control unit is used to disconnect the second switching unit when the first power supply is connected, so as to disconnect the path between the second power supply and the load of the electronic device;

[0061] The second control unit is also used to turn on the second switching unit when the first power supply is disconnected, so as to form a path between the second power supply and the load of the electronic device.

[0062] As described above, power supply switching is achieved through two independent power supply circuits. The first power supply circuit and the second power supply circuit each include a control unit and a switching unit. In the first power supply circuit, when the first power supply is connected, the first control unit conducts the first switching unit, so that the first power supply forms a path with the load of the electronic device. In the second power supply circuit, when the first power supply is connected, the second control unit disconnects the second switching unit, so that the path between the second power supply and the load of the electronic device is disconnected, and when the first power supply is disconnected, the second control unit conducts the second switching unit, so that the second power supply forms a path with the load of the electronic device. Based on this, the two power supply circuits are联动 controlled by the first control unit and the second control unit based on the same power supply, and can disconnect the power supply path of the other power supply when one power supply is connected, and conduct the power supply path of the other power supply when one power supply is disconnected, ensuring that the two power supplies supply power mutually exclusively, so that only one of the two power supplies supplies power, avoiding the situation of simultaneous power supply or no power supply of the two power supplies, and realizing stable switching between battery power supply and external power supply.

[0063] In an embodiment of the present application, the first end of the first switching unit is used to connect the first power supply, the second end of the first switching unit is used to connect the load of the electronic device, and the control end of the first switching unit is connected to the first end of the first control unit;

[0064] The control end of the first control unit is used to connect the first power supply, and the second end of the first control unit is grounded;

[0065] The first end of the second switching unit is used to connect the second power supply, the second end of the second switching unit is used to connect the load of the electronic device, and the control end of the second switching unit is connected to the first end of the second control unit;

[0066] The control end of the second control unit is used to connect the first power supply, and the second end of the second control unit is grounded.

[0067] As described above, by connecting the control end of the first control unit to the first power supply and also connecting the control end of the second control unit to the first power supply,联动 control based on the same power supply is achieved. This design can ensure that when the first power supply is connected, the first power supply circuit can be reliably conducted, while the second power supply circuit can be reliably disconnected; when the first power supply is disconnected, the second power supply circuit can be reliably conducted. This mutually exclusive power supply mechanism avoids the situation of simultaneous power supply or no power supply of the two power supplies, thereby improving the reliability and stability of the circuit and providing a stable power supply switching function for the electronic device.

[0068] In an embodiment of the present application, the first switching unit includes a first transistor and a second transistor;

[0069] The control electrode of the first transistor is connected to the control electrode of the second transistor, and the first main electrode of the first transistor is connected to the first main electrode of the second transistor.

[0070] The second main electrode of the first transistor is used to connect to the first power supply, and the second main electrode of the second transistor is used to connect to the load.

[0071] The control electrodes of the first transistor and the second transistor are connected to the first terminal of the first control unit.

[0072] As described above, the first transistor and the second transistor are controlled in parallel. Therefore, as long as one transistor is turned on, the connection between the first power supply and the load can be guaranteed. In the event of failure of one transistor, the other transistor can still control the conduction state, which effectively improves the reliability of the circuit conduction.

[0073] In one embodiment of this application, the second switching unit includes a third transistor and a fourth transistor;

[0074] The control electrode of the third transistor is connected to the control electrode of the fourth transistor, and the first main electrode of the third transistor is connected to the first main electrode of the fourth transistor.

[0075] The second main electrode of the third transistor is used to connect to the second power supply, and the second main electrode of the fourth transistor is used to connect to the load.

[0076] The control electrodes of the third and fourth transistors are connected to the first terminal of the second control unit.

[0077] As described above, the third and fourth transistors are controlled in parallel. Therefore, as long as one transistor is turned on, the connection between the second power supply and the load can be guaranteed. In the event of a transistor failure, the other transistor can still control the conduction state, which effectively improves the reliability of the circuit conduction.

[0078] In one embodiment of this application, a controlled diode is disposed between the control electrode and the first main electrode of the first transistor, the second transistor, the third transistor, and the fourth transistor.

[0079] As described above, the first end of the controlled diode is connected to the control electrode of the transistor, and the second end of the controlled diode is connected to the first main electrode of the transistor. This allows the power supply signal to directly act on the electrical connection path between the control terminal and the main electrode of the transistor, ensuring that the level adjustment of the power supply signal can accurately control the conduction state of each transistor, ensuring stable switching of dual power supply, and avoiding mutual interference between the power supply signal and the power supply circuit through electrical isolation characteristics.

[0080] In one embodiment of this application, a first terminal of the first switching unit is used to connect to a first power supply, a second terminal of the first switching unit is used to connect to the load of an electronic device, and a control terminal of the first switching unit is connected to a first terminal of a first control unit.

[0081] The control terminal of the first control unit is used to connect to the processor of the electronic device. The second terminal of the first control unit is grounded. When the first power supply is connected, the processor of the electronic device controls the first control unit to turn on the first switching unit.

[0082] The first end of the second switching unit is used to connect to the second power supply, the second end of the second switching unit is used to connect to the load of the electronic device, and the control end of the second switching unit is connected to the first end of the second control unit.

[0083] The control terminal of the second control unit is used to connect to the processor of the electronic device. The second terminal of the second control unit is grounded. When the first power supply is connected, the processor of the electronic device controls the second control unit to disconnect the second switching unit and controls the second control unit to turn on the second switching unit when the first power supply is disconnected.

[0084] As described above, by connecting the control terminals of the first control unit and the second control unit to the processor of the electronic device, the power switching no longer relies on simple power signal detection, but is precisely controlled by the processor according to the system state and logic. This design can flexibly switch the power supply path according to the actual operating needs and power state of the electronic device, ensuring the accuracy and reliability of power switching.

[0085] In one embodiment of this application, both the first power supply circuit and the second power supply circuit include a protection unit;

[0086] The protection unit includes a protection capacitor and a protection resistor;

[0087] The first main electrode is connected to one end of the protection capacitor and one end of the protection resistor, respectively, and the control electrode is connected to the other end of the protection capacitor and the other end of the protection resistor, respectively.

[0088] As described above, by setting up a protection unit containing a combination of capacitors and resistors, a protection circuit with filtering and voltage regulation functions is constructed between the transistor's control electrode and main electrode. The protection capacitor, connected across the control electrode and main electrode, forms a high-frequency filtering path, absorbing voltage spikes and transient interference generated by switching operations. The protection resistor, connected in series with the control electrode, forms a voltage regulation circuit, suppressing the effects of parasitic responses on voltage. The parallel structure of the capacitor and resistor generates a delay effect during sudden potential changes at the control electrode, smoothing the voltage change rate through the RC charging and discharging process, thereby ensuring the safe turn-on and turn-off of the transistor during dual-power supply switching.

[0089] In one embodiment of this application, the first control unit includes a fifth transistor;

[0090] The control electrode of the fifth transistor is used to connect to the first power supply;

[0091] The first main electrode of the fifth transistor is connected to the control electrodes of the first and second transistors, respectively.

[0092] The second main electrode of the fifth transistor is grounded.

[0093] As described above, the first control unit, constructed using the fifth transistor, directly links the first power supply to the control logic of the transistor. The control electrode of the fifth transistor is connected to the first power supply, allowing its operation to be regulated by the voltage of the first power supply. When the first power supply is in operation, the fifth transistor conducts based on the level change of its control electrode, and then outputs a drive signal to the control electrodes of the first and second transistors through the first main electrode, controlling their conduction states. Based on this, the switching unit function is implemented using a single transistor, simplifying the control logic. Simultaneously, the voltage of the first power supply itself is used as the switching trigger condition, avoiding interference from external control signals, thereby accurately switching the power supply path and preventing parallel power supply from both power sources.

[0094] In one embodiment of this application, the second control unit includes a sixth transistor and a seventh transistor;

[0095] The control electrode of the sixth transistor is used to connect to the first power supply;

[0096] The first main electrode of the sixth transistor is connected to the control electrode of the seventh transistor, the first main electrode of the third transistor, and the first main electrode of the fourth transistor, respectively.

[0097] The first main electrode of the seventh transistor is connected to the control electrodes of the third and fourth transistors, respectively.

[0098] The second main electrodes of both the sixth and seventh transistors are grounded.

[0099] As described above, the inverting control function is achieved by cascading the sixth and seventh transistors. The control electrode of the sixth transistor is also controlled by the first power supply. When the first power supply is on, the sixth transistor conducts, pulling the control electrode potential of the seventh transistor low, thus triggering the seventh transistor to turn off. At this time, the seventh transistor forcibly turns off the transistors in the second power supply circuit through the control electrodes of the third and fourth transistors. This cascaded structure directly drives the sixth transistor through the power supply state of the first power supply, and then inverts the signal through the seventh transistor, ensuring that the second power supply circuit and the first power supply circuit always maintain opposite conduction states, thereby reliably cutting off the backup power supply circuit.

[0100] Another embodiment of this utility model provides an electronic device, including the above-described dual-power supply switching circuit.

[0101] In one embodiment of this application, the electronic device may be a POS machine, a self-service terminal, or a payment device, etc.

[0102] The dual-power supply switching circuit provided by this utility model can be applied to electronic devices with dual power supplies. The following is a detailed description of its implementation:

[0103] Example 1

[0104] like Figure 1 and Figure 2 As shown, a dual-power supply switching circuit is used to switch power supply channels for electronic devices. The power supply channels include a first power supply and a second power supply. The switching circuit includes a first power supply circuit 10 and a second power supply circuit 20. The first power supply circuit 10 includes a first control unit 101 and a first switch unit 102. A first terminal of the first switch unit 102 is connected to the first power supply PWR1, and a second terminal of the first switch unit 102 is connected to the load Load of the electronic device. The control terminal of the first switch unit 102 is connected to the first terminal of the first control unit 101, and the control terminal of the first control unit 101 is connected to the first power supply PWR1. The second terminal of the first control unit 101 is grounded. The second power supply circuit 20 includes a second control unit 201 and a second switch unit 202. A first terminal of the second switch unit 202 is connected to the second power supply PWR2, and a second terminal of the second switch unit 202 is connected to the load Load of the electronic device. The control terminal of the second switch unit 202 is connected to the first terminal of the second control unit 201, and the control terminal of the second control unit 201 is connected to the first power supply PWR1. The second terminal of the second control unit 201 is grounded.

[0105] like Figure 3 and Figure 4 As shown, the circuit structure of the first switching unit 102, the second switching unit 202, the first control unit 101 and the second control unit 201 described above will be described in detail below.

[0106] The first switching unit 102 includes a first transistor Q1 and a second transistor Q2. The control electrode 1 of the first transistor Q1 is connected to the control electrode 1 of the second transistor Q2, and the first main electrode 2 of the first transistor Q1 is connected to the first main electrode 2 of the second transistor Q2. The second main electrode 3 of the first transistor Q1 is used to connect to a first power supply PWR1, and the second main electrode 3 of the second transistor Q2 is used to connect to a load Load. The control electrodes 1 of the first transistor Q1 and the second transistor Q2 are connected to the first terminal of the first control unit 101.

[0107] The second switching unit 202 includes a third transistor Q3 and a fourth transistor Q4. The control electrode 1 of the third transistor Q3 is connected to the control electrode 1 of the fourth transistor Q4, and the first main electrode 2 of the third transistor Q3 is connected to the first main electrode 2 of the fourth transistor Q4. The second main electrode 3 of the third transistor Q3 is used to connect to the second power supply PWR2, and the second main electrode 3 of the fourth transistor Q4 is used to connect to the load Load. The control electrodes 1 of the third transistor Q3 and the fourth transistor Q4 are connected to the first terminal of the second control unit 201.

[0108] In one embodiment of this application, the first power supply PWR1 is an external power supply, and the second power supply PWR2 is a battery power supply. In the first power supply circuit 10, the external power supply forms a path with the load Load through the first transistor Q1 and the second transistor Q2; in the second power supply circuit 20, the battery power supply forms a path with the load Load through the third transistor Q3 and the fourth transistor Q4. This achieves isolation between the two power supply channels, and the dual-transistor configuration ensures stable conduction. The second power supply PWR2 can be directly connected to the first terminal of the second switching unit 202 for direct power supply; or, the second power supply PWR2 can be connected to the base of the electronic device, receiving power from the base, and the power supply terminal of the base is connected to the first terminal of the second switching unit 202 for indirect power supply.

[0109] In the circuit structure described above, the first transistor Q1, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 are all P-type MOSFETs. The gate voltage control characteristics of P-type MOSFETs enable them to quickly turn on when the power supply signal is low and reliably turn off when the power supply signal is high. This characteristic, which is naturally matched with digital control signals, ensures that the switching unit can accurately select the power supply path.

[0110] The control electrode 1, the first main electrode 2, and the second main electrode 3 of the first transistor Q1, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 are the gate, source, and drain of the P-type MOSFET, respectively.

[0111] A controlled diode D is disposed between the control electrode 1 and the first main electrode 2 of the first transistor Q1, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4. The controlled diode D is used to receive the power supply signal to adjust the level. The controlled diode D consists of two diodes with their cathodes connected opposite each other. The anode of one diode is connected to the first main electrode 2 of the transistor, and the anode of the other diode is connected to the control electrode 1 of the transistor.

[0112] In this embodiment, the controlled diode D is controlled by a control unit in the power supply circuit. Specifically, when the first power supply PWR1 is connected, a high-level signal is applied to the control terminal of the first control unit 101, and its first terminal generates a low-impedance drive signal in phase with the power supply. This signal controls the level of the controlled diode D to synchronously act on the control electrodes 1 of the first transistor Q1 and the second transistor Q2, so that the control voltage difference between them reaches the conduction threshold. At this time, a path is formed between the first power supply PWR1 and the load Load through the first transistor Q1 and the second transistor Q2. Meanwhile, a high-level signal is applied to the control terminal of the second control unit 201, but its first terminal generates a high-impedance signal in phase with the power supply. This signal controls the level of the controlled diode D to synchronously act on the control electrodes 1 of the third transistor Q3 and the fourth transistor Q4, so that they are turned off. At this time, a path cannot be formed between the second power supply PWR2 and the load Load. In this way, when the first power supply PWR1 is connected, the first power supply PWR1 supplies power regardless of whether the second power supply PWR2 is connected, ensuring that only one of the two power supply circuits is in a conducting state at any time.

[0113] Furthermore, when the first power supply PWR1 is disconnected, a low-level signal is applied to the control terminal of the first control unit 101, causing its first terminal to flip. This signal controls the controlled diode D to synchronously turn off the first transistor Q1 and the second transistor Q2, preventing a path from being formed between the first power supply PWR1 and the load Load. Conversely, a high-level signal is applied to the control terminal of the second control unit 201, generating a low-impedance drive signal that is inversely phase to the power supply. This signal controls the controlled diode D to synchronously turn on the third transistor Q3 and the fourth transistor Q4, forming a path between the second power supply PWR2 and the load Load. In this way, when the first power supply PWR1 is disconnected, the power supply switches to the second power supply PWR2.

[0114] In one embodiment of this application, the first control unit 101 includes a fifth transistor Q5. The control electrode 1 of the fifth transistor Q5 is connected to a first power supply PWR1, the first main electrode 2 of the fifth transistor Q5 is connected to the control electrodes 1 of the first transistor Q1 and the second transistor Q2, and the second main electrode 3 of the fifth transistor Q5 is grounded. Specifically, a resistor R1 is also connected between the control electrode 1 and the second main electrode 3 of the fifth transistor Q5, and the control electrode 1 of the fifth transistor Q5 is connected to the first power supply PWR1 through a resistor R2. Furthermore, the first main electrode 2 of the fifth transistor Q5 is connected to the control electrodes 1 of the first transistor Q1 and the second transistor Q2 through a resistor R3.

[0115] In one embodiment of this application, the second control unit 201 includes a sixth transistor Q6 and a seventh transistor Q7. The control electrode 1 of the sixth transistor Q6 is connected to a first power supply PWR1. The first main electrode 2 of the sixth transistor Q6 is connected to the control electrode 1 of the seventh transistor Q7, the first main electrode 2 of the third transistor Q3, and the first main electrode 2 of the fourth transistor Q4, respectively. The first main electrode 2 of the seventh transistor Q7 is connected to the control electrodes 1 of the third transistor Q3 and the fourth transistor Q4, respectively. The second main electrodes 3 of both the sixth transistor Q6 and the seventh transistor Q7 are grounded. Specifically, a resistor R3 is connected between the control electrode 1 and the second main electrode 3 of the sixth transistor Q6, and the control electrode 1 of the sixth transistor Q6 is connected to the first power supply PWR1 through resistor R4. The first main electrode 2 of the sixth transistor Q6 is connected to the control electrode 1 of the seventh transistor Q7 through resistor R5, and a resistor R6 is connected between the control electrode 1 and the second main electrode 3 of the seventh transistor Q7. Furthermore, the first main electrode 2 of the sixth transistor Q6 is connected to the first main electrodes 2 of the third transistor Q3 and the fourth transistor Q4 through resistor R4, and the first main electrode 2 of the sixth transistor Q6 is also connected to one end of a capacitor C3, the other end of which is grounded. The second main electrode 3 of the seventh transistor Q7 is connected to the control electrode 1 of the third transistor Q3 and the fourth transistor Q4 through resistor R5.

[0116] It should be noted that the fifth transistor Q5, the sixth transistor Q6, and the seventh transistor Q7 mentioned above are transistors. The control electrode 1, the first main electrode 2, and the second main electrode 3 of the fifth transistor Q5, the sixth transistor Q6, and the seventh transistor Q7 are the base, collector, and emitter of the transistors, respectively.

[0117] like Figure 3 and Figure 4 As shown, both the first power supply circuit 10 and the second power supply circuit 20 include a protection unit 30. The protection unit 30 includes a protection capacitor and a protection resistor. The first main electrode 2 is connected to one end of the protection capacitor and one end of the protection resistor, respectively, and the control electrode 1 is connected to the other end of the protection capacitor and the other end of the protection resistor, respectively. Specifically, in the first power supply circuit 10, the protection capacitor is capacitor C1 and the protection resistor is resistor R1; in the second power supply circuit 20, the protection capacitor is capacitor C2 and the protection resistor is resistor R2.

[0118] Based on the above circuit structure, the working principle of the dual-power supply switching circuit of this utility model in different scenarios is as follows:

[0119] When the first power supply PWR1 is connected, it drives the fifth transistor Q5 to conduct, and the first power supply PWR1 pulls the level of the controlled diode D inside the first transistor Q1 high. At this time, a voltage difference is formed across the protection resistor, causing both the first transistor Q1 and the second transistor Q2 to conduct, thus forming a path between the first power supply PWR1 and the load Load. Simultaneously, it drives the sixth transistor Q6 to conduct, causing the seventh transistor Q7 to turn off, thereby controlling the third transistor Q3 and the fourth transistor Q4 to turn off, preventing a path from forming between the second power supply PWR2 and the load Load. At this time, the entire power supply path is powered by the first power supply PWR1 to the load Load.

[0120] When the first power supply PWR1 is disconnected and the second power supply PER2 is connected, the fifth transistor Q5 is turned off. Simultaneously, the first power supply PWR1 pulls the controlled diode D inside the first transistor Q1 low, thus controlling the first transistor Q1 and the second transistor Q2 to turn off, preventing a path from forming between the first power supply PWR1 and the load Load. At the same time, the sixth transistor Q6 is turned off, and the second power supply PWR2 conducts the seventh transistor Q7 through the controlled diode D inside the third transistor Q3. A voltage difference is then created across the protection resistor, causing both the third transistor Q3 and the fourth transistor Q4 to conduct, thus forming a path between the second power supply PWR2 and the load Load. At this point, the entire power supply path is powered by the second power supply PWR2 to the load Load.

[0121] Example 2

[0122] like Figure 5 As shown, a dual-power supply switching circuit differs from Embodiment 1 in that:

[0123] The control terminal of the first control unit 101 is used to connect to the processor of the electronic device. The second terminal of the first control unit 101 is grounded. When the first power supply PWR1 is connected, the processor of the electronic device controls the first control unit 101 to turn on the first switching unit 102.

[0124] The control terminal of the second control unit 201 is used to connect to the processor of the electronic device. The second terminal of the second control unit 201 is grounded. When the first power supply PWR1 is connected, the processor of the electronic device controls the second control unit 201 to disconnect the second switch unit 202 and controls the second control unit 201 to turn on the second switch unit 202 when the first power supply is disconnected.

[0125] The processor of the electronic device can receive the connection status of the first power supply PWR1 and the second power supply PWR2.

[0126] Specifically, when the first power supply is connected, the processor sends a high-level signal to the first control unit 101 of the first power supply circuit 10 and the second control unit 201 of the second power supply circuit 20. At this time, a high-level signal is applied to the control terminal of the first control unit 101, and its first terminal generates a low-impedance drive signal in phase with the power supply. This signal controls the level of the controlled diode D to synchronously act on the control electrodes 1 of the first transistor Q1 and the second transistor Q2, causing the control voltage difference between them to reach the conduction threshold. At this time, a path is formed between the first power supply PWR1 and the load Load through the first transistor Q1 and the second transistor Q2. Meanwhile, a high-level signal is applied to the control terminal of the second control unit 201, but its first terminal generates a high-impedance signal out of phase with the power supply. This signal controls the level of the controlled diode D to synchronously act on the control electrodes 1 of the third transistor Q3 and the fourth transistor Q4, causing them to be turned off. At this time, a path cannot be formed between the second power supply PWR2 and the load Load.

[0127] When the first power supply PWR1 is disconnected, the processor sends a low-level signal to the first control unit 101 of the first power supply circuit 10 and the second control unit 201 of the second power supply circuit 20. At this time, a low-level signal is applied to the control terminal of the first control unit 101, causing its first terminal to flip. This signal controls the controlled diode D to synchronously turn off the first transistor Q1 and the second transistor Q2, preventing a path from forming between the first power supply PWR1 and the load Load. Conversely, a high-level signal is applied to the control terminal of the second control unit 201, generating a low-impedance drive signal that is inversely phase to the power supply. This signal controls the controlled diode D to synchronously turn on the third transistor Q3 and the fourth transistor Q4, forming a path between the second power supply PWR2 and the load Load. In this way, when the first power supply PWR1 is disconnected, the power supply switches to the second power supply PWR2.

[0128] Example 3

[0129] An electronic device includes a dual-power supply switching circuit as described in Embodiment 1 or Embodiment 2 above.

[0130] In summary, this invention provides a dual-power supply switching circuit and electronic device. It achieves automatic power switching through two independent power supply circuits, ensures stable switching of a single power supply based on the linkage control of the control unit, and precisely controls the power supply status of each power supply based on the independent setting of the switching unit. The controlled diodes can precisely adjust their levels, avoiding mutual interference between the power supply signal and the power supply circuit. The first control unit in the first power supply circuit and the second control unit in the second power supply circuit achieve mutually exclusive conduction of the two power supply circuits, preventing simultaneous power supply or no power supply from either power source, thus achieving stable switching between battery power and external power supply. The protection unit effectively avoids the risk of transistor breakdown due to overvoltage difference, ensuring the safety of the switching process. The power supply circuit of this invention can quickly respond to power supply signals, achieving efficient and reliable power supply switching.

[0131] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent modifications made based on the content of this utility model specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A dual-power supply switching circuit, characterized in that, This circuit is used to switch power supply channels for electronic devices, wherein the power supply channels include a first power supply and a second power supply; the switching circuit includes a first power supply circuit and a second power supply circuit. The first power supply circuit includes a first control unit and a first switching unit; the second power supply circuit includes a second control unit and a second switching unit. The first power supply circuit is used to connect the first power source and the load of the electronic device, so that the first power source and the load of the electronic device form a path. The second power supply circuit is used to connect the second power source and the load of the electronic device, so that the second power source and the load of the electronic device form a path; The first control unit is used to turn on the first switching unit when the first power supply is connected, so that the first power supply and the load of the electronic device form a path; The second control unit is used to disconnect the second switching unit when the first power supply is connected, so as to disconnect the path between the second power supply and the load of the electronic device; The second control unit is further configured to turn on the second switching unit when the first power supply is disconnected, so that the second power supply and the load of the electronic device form a path.

2. The dual-power supply switching circuit according to claim 1, characterized in that, The first end of the first switching unit is used to connect to the first power supply, the second end of the first switching unit is used to connect to the load of the electronic device, and the control end of the first switching unit is connected to the first end of the first control unit. The control terminal of the first control unit is used to connect to the first power supply, and the second terminal of the first control unit is grounded; The first end of the second switching unit is used to connect to the second power supply, the second end of the second switching unit is used to connect to the load of the electronic device, and the control end of the second switching unit is connected to the first end of the second control unit; The control terminal of the second control unit is used to connect to the first power supply, and the second terminal of the second control unit is grounded.

3. The dual-power supply switching circuit according to claim 2, characterized in that, The first switching unit includes a first transistor and a second transistor; The control electrode of the first transistor is connected to the control electrode of the second transistor, and the first main electrode of the first transistor is connected to the first main electrode of the second transistor. The second main electrode of the first transistor is used to connect to the first power supply, and the second main electrode of the second transistor is used to connect to the load of the electronic device; The control electrodes of the first transistor and the second transistor are connected to the first terminal of the first control unit.

4. The dual-power supply switching circuit according to claim 3, characterized in that, The second switching unit includes a third transistor and a fourth transistor; The control electrode of the third transistor is connected to the control electrode of the fourth transistor, and the first main electrode of the third transistor is connected to the first main electrode of the fourth transistor. The second main electrode of the third transistor is used to connect to the second power supply, and the second main electrode of the fourth transistor is used to connect to the load of the electronic device; The control electrodes of the third transistor and the fourth transistor are connected to the first terminal of the second control unit.

5. A dual-power supply switching circuit according to claim 4, characterized in that, A controlled diode is disposed between the control electrode and the first main electrode of the first transistor, the second transistor, the third transistor, and the fourth transistor.

6. The dual-power supply switching circuit according to claim 1, characterized in that, The first end of the first switching unit is used to connect to the first power supply, the second end of the first switching unit is used to connect to the load of the electronic device, and the control end of the first switching unit is connected to the first end of the first control unit. The control terminal of the first control unit is used to connect to the processor of the electronic device, and the second terminal of the first control unit is grounded. When the first power supply is connected, the processor of the electronic device controls the first control unit to turn on the first switching unit. The first end of the second switching unit is used to connect to the second power supply, the second end of the second switching unit is used to connect to the load of the electronic device, and the control end of the second switching unit is connected to the first end of the second control unit; The control terminal of the second control unit is used to connect to the processor of the electronic device. The second terminal of the second control unit is grounded. When the first power supply is connected, the processor of the electronic device controls the second control unit to disconnect the second switching unit and when the first power supply is disconnected, it controls the second control unit to turn on the second switching unit.

7. The dual-power supply switching circuit according to claim 4, characterized in that, Both the first power supply circuit and the second power supply circuit include a protection unit; The protection unit includes a protection capacitor and a protection resistor; The first main electrode is connected to one end of the protection capacitor and one end of the protection resistor, respectively, and the control electrode is connected to the other end of the protection capacitor and the other end of the protection resistor, respectively.

8. A dual-power supply switching circuit according to claim 3, characterized in that, The first control unit includes a fifth transistor; The control electrode of the fifth transistor is used to connect to the first power supply; The first main electrode of the fifth transistor is connected to the control electrodes of the first transistor and the second transistor, respectively. The second main electrode of the fifth transistor is grounded.

9. A dual-power supply switching circuit according to claim 4, characterized in that, The second control unit includes a sixth transistor and a seventh transistor; The control electrode of the sixth transistor is used to connect to the first power supply; The first main electrode of the sixth transistor is connected to the control electrode of the seventh transistor, the first main electrode of the third transistor, and the first main electrode of the fourth transistor, respectively. The first main electrode of the seventh transistor is connected to the control electrodes of the third transistor and the fourth transistor, respectively; The second main electrodes of both the sixth transistor and the seventh transistor are grounded.

10. An electronic device, characterized in that, Includes a dual-power supply switching circuit as described in any one of claims 1 to 9.

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