Constant-voltage constant-current adjustable power supply and electronic equipment

Abstract

The utility model relates to a constant-voltage constant-current adjustable power supply and electronic equipment. The constant-voltage constant-current adjustable power supply comprises a constant-voltage circuit used for outputting constant voltage, a constant-current circuit used for outputting constant current, a signal adjusting circuit connected with the constant-voltage circuit and the constant-current circuit, and an output circuit connected with the signal adjusting circuit. The signal conditioning circuit determines a voltage signal output by the constant voltage circuit according to a voltage setting signal in a constant voltage mode, or determines a current signal output by the constant current circuit according to a current setting signal in a constant current mode. And the output circuit determines a power supply output signal according to the voltage signal or the current signal. According to the constant-voltage constant-current adjustable power supply, voltage or current adjustment is carried out according to a hardware circuit, rapid adjustment of the output power supply signal can be realized, and the error of the output power supply output signal is small. In addition, the power supply circuit is simple in circuit design, few in heating elements, low in heat dissipation cost and high in applicability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of constant voltage and constant current power supply, in particular to a constant voltage and constant current adjustable power supply and electronic equipment. BACKGROUND

[0002] The constant voltage and constant current adjustable power supply is a power supply device that can provide constant voltage and constant current at the same time, and is widely used in places that require stable power supply such as production and testing. The constant voltage and constant current adjustable power supply can automatically switch between constant voltage and constant current modes to adapt to changes in load. However, the circuit design of the traditional constant voltage and constant current adjustable power supply is complex, and the increase in the number of circuit components increases the heat generating components in the constant voltage and constant current adjustable power supply, resulting in high heat dissipation cost. CONTENT OF THE UTILITY MODEL

[0003] Therefore, it is necessary to provide a constant voltage and constant current power supply and electronic equipment with simple design, few heat generating components, low cost and high precision.

[0004] In a first aspect, the present disclosure provides a constant voltage and constant current adjustable power supply, comprising a constant voltage circuit for outputting constant voltage, and a constant current circuit for outputting constant current, the constant voltage and constant current adjustable power supply further comprising:

[0005] a signal conditioning circuit, connected with the constant voltage circuit and the constant current circuit, for determining a voltage signal output by the constant voltage circuit according to a voltage setting signal in a constant voltage mode, or determining a current signal output by the constant current circuit according to a current setting signal in a constant current mode;

[0006] an output circuit, connected with the signal conditioning circuit, for determining a power supply output signal according to the voltage signal or the current signal.

[0007] In some embodiments, the constant voltage circuit comprises a first operational amplifier unit, a non-inverting input terminal of the first operational amplifier unit is connected with a voltage setting signal terminal, an inverting input terminal of the first operational amplifier unit is connected with a voltage gain feedback unit, the voltage gain feedback unit is connected with the output circuit, and an output terminal of the first operational amplifier unit is connected with the signal conditioning circuit.

[0008] In some embodiments, the non-inverting input terminal of the first operational amplifier unit is connected with the voltage setting signal terminal through a first resistor; the voltage gain feedback unit comprises a second resistor and a third resistor, both the second resistor and the third resistor are connected with the inverting input terminal of the first operational amplifier unit, one end of the second resistor is grounded, and the other end of the third resistor is connected with the output circuit.

[0009] In some embodiments, the third resistor is further connected with a first compensation capacitor in parallel.

[0010] In some embodiments, the constant current circuit comprises a second operational amplifier unit, the non-inverting input terminal of the second operational amplifier unit is connected with the current setting signal terminal, the non-inverting input terminal of the second operational amplifier unit is also connected with the first voltage follower, the inverting input terminal of the second operational amplifier unit is connected with the second voltage follower, the first voltage follower and the second voltage follower are respectively connected with two ends of the sampling resistor; and the output terminal of the second operational amplifier unit is connected with the signal adjusting circuit.

[0011] In some embodiments, the first voltage follower comprises a third operational amplifier unit, the output terminal of the third operational amplifier unit is connected with the inverting input terminal of the second operational amplifier unit through a fourth resistor, the non-inverting input terminal of the third operational amplifier unit is connected with the first end of the sampling resistor, and the inverting input terminal of the third operational amplifier unit is connected with the output terminal of the third operational amplifier unit.

[0012] The second voltage follower comprises a fourth operational amplifier unit, the output terminal of the fourth operational amplifier unit is connected with the non-inverting input terminal of the second operational amplifier unit through a fifth resistor, the non-inverting input terminal of the fourth operational amplifier unit is connected with the second end of the sampling resistor, and the inverting input terminal of the fourth operational amplifier unit is connected with the output terminal of the fourth operational amplifier unit.

[0013] In some embodiments, a second compensation capacitor is further connected between the inverting input terminal and the output terminal of the second operational amplifier unit.

[0014] In some embodiments, the signal adjusting circuit comprises a first triode, a second triode, a sixth resistor, a seventh resistor and an eighth resistor, the first end of the first triode is connected with the constant voltage circuit, the second end of the first triode is connected with the power supply through the sixth resistor, the third end of the first triode is connected with the second end of the second triode through the seventh resistor, the first end of the second triode is connected with the constant current circuit, and the third end of the second triode is grounded through the eighth resistor.

[0015] In some embodiments, the output circuit comprises a MOS tube and a ninth resistor, the first end of the MOS tube is connected with one end of the sixth resistor through the ninth resistor, the second end of the MOS tube is connected with the power supply, and the third end of the MOS tube is connected with the power output signal terminal.

[0016] In a second aspect, the present disclosure provides an electronic device comprising the constant voltage and constant current adjustable power supply according to the first aspect.

[0017] The constant-voltage constant-current adjustable power supply and the electronic device, in the constant-voltage constant-current adjustable power supply, include a constant-voltage circuit for outputting a constant voltage, a constant-current circuit for outputting a constant current, a signal adjusting circuit connected with the constant-voltage circuit and the constant-current circuit, and an output circuit connected with the signal adjusting circuit. The signal adjusting circuit determines a voltage signal output by the constant-voltage circuit according to a voltage setting signal in a constant-voltage mode, or determines a current signal output by the constant-current circuit according to a current setting signal in a constant-current mode, so as to determine a power supply output signal according to the voltage signal or the current signal through the output circuit. The constant-voltage constant-current adjustable power supply of the present disclosure can realize fast adjustment of the power supply output signal according to the hardware circuit for voltage or current adjustment, and obtain a power supply output signal with small output error and high precision. In addition, the circuit design of the power supply circuit of the present disclosure is simple, the heating elements are few, and the manufacturing and maintenance costs are low. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 Structure schematic diagram of a constant-voltage constant-current adjustable power supply of an embodiment;

[0020] Figure 2 Structure schematic diagram of a constant-voltage circuit of an embodiment;

[0021] Figure 3 Circuit schematic diagram of a constant-voltage circuit of an embodiment;

[0022] Figure 4 Structure schematic diagram of a constant-current circuit of an embodiment;

[0023] Figure 5 Circuit schematic diagram of a constant-current circuit of an embodiment;

[0024] Figure 6 Circuit schematic diagram of a signal adjusting circuit of an embodiment;

[0025] Figure 7 Circuit diagram of a constant-voltage constant-current adjustable power supply of an embodiment.

[0026] BRIEF DESCRIPTION OF DRAWINGS

[0027] 100, constant-voltage circuit; 200, constant-current circuit; 300, signal adjusting circuit; 400, output circuit. DETAILED DESCRIPTION

[0028] For the purpose of clarity, the present application will be described in greater detail below with reference to the accompanying drawings. The embodiments of the present application are shown in the drawings. However, the present application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0030] It should be understood that the terms "first", "second" and so on used herein can be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from another element. For example, without departing from the scope of the present application, a first resistor can be referred to as a second resistor, and similarly, a second resistor can be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0031] It should be understood that "connection" in the following embodiments, if the circuits, modules, units and the like connected to each other have the transmission of electrical signals or data, should be understood as "electrical connection", "communication connection" and the like.

[0032] It should be understood that "at least one" means one or more, and "multiple" means two or more. "At least part of the element" means part or all of the element.

[0033] As used herein, the singular forms "a", "an" and "the" can also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "comprise / contain" or "have" and the like specify the presence of stated features, integers, steps, operations, components, parts or combinations thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, components, parts or combinations thereof. At the same time, the term "and / or" used in the specification includes any and all combinations of the related listed items.

[0034] Constant voltage and constant current adjustable power supply is a kind of adjustable power supply which can automatically switch between constant voltage mode and constant current mode to adapt to the change of load. For example, in constant voltage mode, constant voltage and constant current power supply will maintain a constant voltage signal output; as the load increases, the current output by the power supply also increases; when the current reaches the set limit value, the constant voltage and constant current power supply will automatically switch to constant current mode, at which time the output current remains stable, and the output voltage changes with the change of load.

[0035] The circuit design of the traditional constant voltage and constant current adjustable power supply is complex, and the increase in the number of circuit components increases the heat generating components in the constant voltage and constant current adjustable power supply, and increases the manufacturing and maintenance costs. Figure 1 As shown in the embodiment, a constant voltage and constant current adjustable power supply is provided, which comprises a constant voltage circuit 100 for outputting a constant voltage, a constant current circuit 200 for outputting a constant current, a signal adjusting circuit 300 connected with the constant voltage circuit 100 and the constant current circuit 200, and an output circuit 400 connected with the signal adjusting circuit. The signal adjusting circuit 300 determines a voltage signal output by the constant voltage circuit 100 according to a voltage setting signal in a constant voltage mode, or determines a current signal output by the constant current circuit 200 according to a current setting signal in a constant current mode. The output circuit 400 determines a power supply output signal according to the voltage signal or the current signal.

[0036] The embodiment can feedback adjust the constant voltage and constant current adjustable power supply through a hardware circuit, has high adjustment efficiency and fast response speed, and can improve the adjustment efficiency of the constant voltage and constant current adjustable power supply.

[0037] Please refer to Figure 2 The structure diagram of the constant voltage circuit 100. In some exemplary embodiments, the constant voltage circuit 100 comprises a first operational amplifier unit. The non-inverting input terminal of the first operational amplifier unit is used to be connected with the voltage setting signal end. The inverting input terminal of the first operational amplifier unit is connected with a voltage gain feedback unit, and the voltage gain feedback unit is used to be connected with the output circuit 400; the output terminal of the first operational amplifier unit is connected with the signal adjusting circuit 300.

[0038] Please refer to Figure 3 The circuit diagram of the constant voltage circuit 100. In some specific embodiments, the first operational amplifier unit is represented as U1, and the voltage setting signal end is represented as V4. The voltage gain feedback unit comprises a second resistor R2 and a third resistor R3. The non-inverting input terminal of the first operational amplifier unit U1 is connected with the voltage setting signal end of the voltage setting signal V4 through a first resistor R1. The second resistor R2 and the third resistor R3 are both connected with the inverting input terminal of the first operational amplifier unit U1, one end of the second resistor R2 is grounded, and the other end of the third resistor R3 is connected with the output circuit 400. The output terminal of the first operational amplifier unit is also connected with the inverting input terminal of the first operational amplifier unit through a capacitor C3.

[0039] Correspondingly, in some specific embodiments, the third resistor R3 is also connected with a first compensation capacitor C2 in parallel. The first compensation capacitor C2 performs loop compensation on the constant voltage circuit 100. By adding a compensation capacitor to the gain feedback circuit, the stability of the system can be ensured when the output voltage of the constant voltage circuit 100 is adjusted.

[0040] In the constant voltage circuit 100, the first operational amplifier unit U1 amplifies the voltage setting signal and transmits the amplified voltage signal to the signal conditioning circuit 300. Simultaneously, the constant voltage circuit 100 also receives a feedback signal from the output circuit 400. The constant voltage circuit 100 can adjust the output voltage signal based on the feedback signal from the output circuit 400.

[0041] Please refer to Figure 4 The diagram shows the structure of the constant current circuit 200. In some embodiments, the constant current circuit 200 includes a second operational amplifier unit. The non-inverting input of the second operational amplifier unit is connected to the current setting signal terminal, the inverting input of the second operational amplifier unit is connected to the first voltage follower, and the non-inverting input of the second operational amplifier unit is also connected to the second voltage follower. The first and second voltage followers are respectively connected to the two ends of the sampling resistor, and the output of the second operational amplifier unit is connected to the signal conditioning circuit.

[0042] Please refer to Figure 5 The circuit diagram of the constant current circuit 200 is shown. In some specific embodiments, the second operational amplifier unit is denoted as U2, and the current setting signal terminal is denoted as V3. The first voltage follower includes a third operational amplifier unit, and the second voltage follower includes a fourth operational amplifier unit; the third operational amplifier unit is denoted as U3, and the fourth operational amplifier unit is denoted as U4.

[0043] like Figure 5 As shown, the output terminal of the third operational amplifier unit U3 is connected to the inverting input terminal of the second operational amplifier unit U2 through the fourth resistor R4. The non-inverting input terminal of the third operational amplifier unit U3 is connected to the first terminal of the sampling resistor R12, and the inverting input terminal of the third operational amplifier unit U3 is connected to its output terminal. The output terminal of the fourth operational amplifier unit U4 is connected to the non-inverting input terminal of the second operational amplifier unit U2 through the fifth resistor R5. The non-inverting input terminal of the fourth operational amplifier unit U4 is connected to the second terminal of the sampling resistor R12, and the inverting input terminal of the fourth operational amplifier unit U4 is connected to its output terminal.

[0044] Correspondingly, in some specific embodiments, a second compensation capacitor C4 is also connected between the inverting input terminal and the output terminal of the second operational amplifier unit U2. The second compensation capacitor C4 performs loop compensation for the constant current circuit 200, which can ensure the stability of the system when the output circuit of the constant current circuit 200 is adjusted for current.

[0045] In the constant current circuit 200, the second operational amplifier unit U2 amplifies the current setting signal and transmits the amplified current signal to the signal adjusting circuit 300. Meanwhile, the constant current circuit 200 is also provided with a voltage follower circuit which collects the voltage values at both ends of the sampling resistor and is connected to the non-inverting input terminal and the inverting input terminal of the second operational amplifier unit U2 through resistors R4 and R5 respectively. It can be understood that the sampling resistor R12 is connected to the power output signal of the output circuit 400 for sampling the power output signal.

[0046] Please refer to Figure 6 In some exemplary embodiments, the signal adjusting circuit 300 comprises a first triode Q1, a second triode Q2, a sixth resistor R6, a seventh resistor R7 and an eighth resistor R8. The first end of the first triode Q1 is connected to the constant voltage circuit 100, the second end of the first triode Q2 is connected to the power supply through the sixth resistor R6, the third end of the first triode Q1 is connected to the second end of the second triode Q2 through the seventh resistor R7, the first end of the second triode Q2 is connected to the constant current circuit 200, and the third end of the second triode Q2 is grounded through the eighth resistor R8. The power supply can be 24V.

[0047] As Figure 6 shown, the signal adjusting circuit 300 determines the conduction of the first triode Q1 through the voltage signal output by the constant voltage circuit 100 and determines the conduction of the second triode Q2 through the current signal output by the constant current circuit 200. When the current of the output circuit 400 is sampled and the current does not reach the current setting signal, the voltage at the non-inverting input terminal of the second operational amplifier unit U2 is greater than the voltage at the inverting input terminal, the output terminal of the second operational amplifier unit U2 outputs a positive voltage power supply V+, the second triode Q2 is fully open, and the first triode Q1 works in the linear region, so that the voltage at both ends of the resistor R6 is dynamically adjusted, and the output voltage signal is controllable. When working in constant current mode, the first triode Q1 is fully open, the second triode Q2 works in the linear region, and the output current signal is controllable through the dynamic adjustment of the voltage at both ends of the resistor R6.

[0048] Please refer to Figure 7 the circuit diagram of the constant voltage and constant current adjustable power supply. In other embodiments, the output circuit 400 comprises a MOS tube and a ninth resistor. The first end of the MOS tube M1 is connected to one end of the sixth resistor R6 through the ninth resistor R9, the second end of the MOS tube M1 is connected to the power supply, and the third end of the MOS tube M1 is connected to the power output signal end.

[0049] The output circuit 400 works according to the signal adjusting circuit 300 to output a power output signal to realize constant voltage or constant current output. The output circuit 400 includes a MOS transistor M1, the G pole gate and the S pole source of the MOS transistor M1 are connected to both ends of the resistor R6, the voltage between both ends of the resistor R6 represents the voltage between the G pole and the S pole of the MOS transistor M1, and the switching state of the MOS transistor M1 is determined according to the voltage difference between the G pole and the S pole. In the circuit diagram of the embodiment, the S pole is connected to the power supply, and the D pole drain is connected to the output signal end.

[0050] The constant voltage and constant current adjustable power supply can control the output gain according to the setting of the resistance value in the constant voltage and constant current adjustable circuit during work. For example, when the set output gain is 10 times, the voltage output by the constant voltage circuit 100 is 1V, and the power output signal output by the output circuit 400 is 10V. The corresponding relationship of the output signal of the constant current circuit 200 is set to 1V corresponding to 1A, when the control signal of the constant current circuit 200 is set to 1V, the maximum current output by the output circuit 400 is 1A, when the current output by the output circuit 400 reaches 1A, the constant voltage and constant current adjustable power supply works in constant current mode, and with the change of the load, the output voltage value is changed to meet the constant 1A output current.

[0051] When the constant voltage and constant current adjustable power supply works in constant voltage mode, the output 5V constant voltage is set, the voltage setting signal V4 is set to 0.5V, the current setting signal V3 is set to the maximum value, the current value obtained by sampling the output circuit 400 is less than the current setting value, and the constant voltage and constant current adjustable power supply outputs a constant voltage 5V voltage signal.

[0052] When the constant voltage and constant current adjustable power supply works in constant current mode, the output 1A constant current is set, the current setting signal V3 is set to 1V, the voltage setting signal V4 is set to the maximum value, the current value obtained by sampling the output circuit 400 reaches the set current value, and the constant voltage and constant current adjustable power supply outputs a constant current 1A current signal.

[0053] The constant voltage and constant current adjusting function of the embodiment is realized by a hardware circuit, the adjusting speed is fast, and the adjusting efficiency is high. The constant voltage error of the constant voltage and constant current adjustable power supply of the embodiment is less than 1mV, and the constant current error is less than 1mA. At the same time, since the constant voltage and constant current adjustable power supply of the embodiment only sets one MOS transistor, it is a single MOS transistor constant voltage and constant current adjustable power supply. Compared with other constant voltage and constant current adjustable power supplies with multiple MOS transistors, the number of MOS transistors is reduced, the manufacturing cost and circuit area of the constant voltage and constant current adjustable power supply are reduced. In addition, due to the reduction of the number of MOS transistors, the main heat source of the constant voltage and constant current adjustable power supply is reduced, and the heat dissipation cost of the constant voltage and constant current adjustable power supply is reduced.

[0054] The constant voltage and constant current adjustable power supply can be applied to places such as production, testing and other places that need stable power supply or corresponding electronic equipment.

[0055] In some embodiments, an electronic device is provided, which includes the constant-voltage constant-current adjustable power supply disclosed in any of the above embodiments. The electronic device is powered by the constant-voltage constant-current adjustable power supply, and stable power supply can be obtained when the load changes, and the reliability is high.

[0056] In the description of the specification, the description referring to the terms "some embodiments", "other embodiments", and the like means that the particular feature, structure, material, or characteristic being described is included in at least some embodiments or examples of the present application. The illustrative description of these terms in this specification is not necessarily referring to the same embodiment or example.

[0057] The technical features of the above-described embodiments can be combined in any manner. In order to make the description simple, all possible combinations of the technical features in the above-described embodiments are not described, however, as long as the combinations of the technical features do not contradict each other, they should be considered as falling within the scope of the present application.

[0058] The above-described embodiments only express several implementation manners of the present application, and the description is specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be pointed out that, for those skilled in the art, some modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A constant voltage and constant current adjustable power supply, characterized in that, The adjustable power supply includes a constant voltage circuit for outputting a constant voltage and a constant current circuit for outputting a constant current. The constant voltage and constant current power supply further includes: A signal conditioning circuit, which is connected to both the constant voltage circuit and the constant current circuit, is used to determine the voltage signal output by the constant voltage circuit according to the voltage setting signal in constant voltage mode, or to determine the current signal output by the constant current circuit according to the current setting signal in constant current mode. An output circuit, connected to the signal conditioning circuit, is used to determine the power output signal based on the voltage signal or the current signal.

2. The constant voltage and constant current adjustable power supply according to claim 1, characterized in that, The constant voltage circuit includes a first operational amplifier unit. The non-inverting input terminal of the first operational amplifier unit is connected to a voltage setting signal terminal, and the inverting input terminal of the first operational amplifier unit is connected to a voltage gain feedback unit. The voltage gain feedback unit is connected to the output circuit. The output terminal of the first operational amplifier unit is connected to the signal conditioning circuit.

3. The constant voltage and constant current adjustable power supply according to claim 2, characterized in that, The non-inverting input terminal of the first operational amplifier unit is connected to the voltage setting signal terminal through a first resistor; the voltage gain feedback unit includes a second resistor and a third resistor, both of which are connected to the inverting input terminal of the first operational amplifier unit, the other end of the second resistor is grounded, and the other end of the third resistor is connected to the output circuit.

4. The constant voltage and constant current adjustable power supply according to claim 3, characterized in that, The third resistor is also connected in parallel with the first compensation capacitor.

5. The constant voltage and constant current adjustable power supply according to claim 1, characterized in that, The constant current circuit includes a second operational amplifier unit. The non-inverting input terminal of the second operational amplifier unit is connected to the current setting signal terminal. The non-inverting input terminal of the second operational amplifier unit is also connected to a first voltage follower. The inverting input terminal of the second operational amplifier unit is connected to a second voltage follower. The first voltage follower and the second voltage follower are respectively connected to the two ends of the sampling resistor. The output terminal of the second operational amplifier unit is connected to the signal conditioning circuit.

6. The constant voltage and constant current adjustable power supply according to claim 5, characterized in that, The first voltage follower includes a third operational amplifier unit. The output terminal of the third operational amplifier unit is connected to the inverting input terminal of the second operational amplifier unit through a fourth resistor. The non-inverting input terminal of the third operational amplifier unit is connected to the first terminal of the sampling resistor. The inverting input terminal of the third operational amplifier unit is connected to the output terminal of the third operational amplifier unit. The second voltage follower includes a fourth operational amplifier unit. The output terminal of the fourth operational amplifier unit is connected to the non-inverting input terminal of the second operational amplifier unit through a fifth resistor. The non-inverting input terminal of the fourth operational amplifier unit is connected to the second terminal of the sampling resistor. The inverting input terminal of the fourth operational amplifier unit is connected to the output terminal of the fourth operational amplifier unit.

7. The constant voltage and constant current adjustable power supply according to claim 6, characterized in that, A second compensation capacitor is also connected between the inverting input terminal and the output terminal of the second operational amplifier unit.

8. The constant voltage and constant current adjustable power supply according to claim 1, characterized in that, The signal conditioning circuit includes a first transistor, a second transistor, a sixth resistor, a seventh resistor, and an eighth resistor. The first terminal of the first transistor is connected to the constant voltage circuit, the second terminal of the first transistor is connected to the power supply through the sixth resistor, the third terminal of the first transistor is connected to the second terminal of the second transistor through the seventh resistor, the first terminal of the second transistor is connected to the constant current circuit, and the third terminal of the second transistor is grounded through the eighth resistor.

9. The constant voltage and constant current adjustable power supply according to claim 8, characterized in that, The output circuit includes a MOSFET and a ninth resistor. The first end of the MOSFET is connected to one end of the sixth resistor through the ninth resistor. The second end of the MOSFET is connected to the power supply. The third end of the MOSFET is connected to the power output signal terminal.

10. An electronic device, characterized in that, Includes a constant voltage and constant current adjustable power supply according to any one of claims 1-9.

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