Output selection circuit and direct-current UPS (Uninterrupted Power Supply)

Abstract

The utility model relates to the technical field of power electronics, in particular to an output selection circuit and a direct-current UPS (Uninterrupted Power Supply). The output selection circuit comprises a main control chip, an output switching module and a voltage regulation module. A first end of the output switching module is connected with an external DC power supply, a second end is connected with a storage battery of the DC UPS power supply, a third end is connected with an output end of the main control chip, and a fourth end is connected with the voltage regulation module; the output switching module is used for receiving a selection signal of the main control chip and selectively transmitting a first voltage signal of an external direct-current power supply or a second voltage signal of a storage battery to the voltage adjusting module; the voltage adjusting module is used for adjusting the first voltage signal or the second voltage signal to a target voltage signal for output. The output switching module is controlled by the main control chip to output the voltage of the external direct current power supply or the voltage of the storage battery, and the output voltage is converted into a target voltage signal by using the voltage regulation module, so that the UPS as the back-up power supply has the multi-path output capability.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, in particular to an output selection circuit and a DC UPS power supply. Background Art

[0002] Uninterruptible Power System (UPS) is an electronic device that can provide continuous, stable, and uninterrupted power supply. It can provide constant voltage and frequency uninterruptible power supply for monitoring systems, automation instruments, remote communication systems and other equipment in substations. It is used to prevent sudden power outages from affecting normal operation and causing damage to equipment.

[0003] At present, UPS can continue to supply power to equipment as a backup power source when the mains power is disconnected. Generally, 220V AC input is used to power the UPS, and there is no DC input method, nor is there the ability to output multiple DC channels. At the same time, the existing UPS cannot monitor the working status of the UPS power supply, nor can the UPS working status be remotely set.

[0004] The above contents are only used to assist in understanding the technical solution of the present utility model and do not constitute an admission that the above contents are prior art. Utility Model Content

[0005] The main purpose of the utility model is to provide an output selection circuit and a DC UPS power supply, aiming to solve the technical problem in the prior art that the UPS does not have the ability of DC multi-channel output, resulting in limited application scenarios.

[0006] To achieve the above object, the utility model provides an output selection circuit, which includes: a main control chip, an output switching module and a voltage regulation module;

[0007] The first end of the output switching module is connected to the external DC power supply, the second end is connected to the battery of the DC UPS power supply, the third end is connected to the output end of the main control chip, and the fourth end is connected to the voltage regulation module;

[0008] The output switching module is used to receive the selection signal of the main control chip and select to transmit the first voltage signal of the external DC power supply or the second voltage signal of the battery to the voltage regulation module;

[0009] The voltage regulating module is used to regulate the first voltage signal or the second voltage signal to a target voltage signal for output.

[0010] Optionally, the output switching module includes: four conduction control units;

[0011] The control end of each conduction control unit is connected to the main control chip, the input end of each conduction control unit is connected to the corresponding battery or external DC power supply, and the output end of each conduction control unit is connected to the voltage regulation module;

[0012] The conduction control unit is used to receive a selection signal from the main control chip and conduct the circuit between the corresponding battery or external DC power supply and the voltage regulation module.

[0013] Optionally, each of the conduction control units includes: a first resistor, a second resistor, a first switch tube, a second switch tube, a diode and a relay;

[0014] The first end of the relay is connected to the corresponding battery or external DC power supply, the second end of the relay is connected to the voltage regulation module, the control end of the first switch tube is connected to the first end of the first resistor and the main control chip at the same time, the input end of the first switch tube is connected to the first end of the second resistor and the control end of the second switch tube at the same time, the output ends of the first switch tube and the second switch tube are both grounded, the second end of the first resistor is connected to the second end of the second resistor, the cathode of the diode and the third end of the relay at the same time, and the input end of the second switch tube is connected to the anode of the diode and the fourth end of the relay at the same time.

[0015] Optionally, the voltage regulation module includes: a voltage boost unit and a voltage drop unit;

[0016] The input end of the boost unit is connected to the output end of the output switching module, the output end of the boost unit is used to output the target voltage signal, the input end of the buck unit is connected to the output end of the output switching module, and the output end of the buck unit is used to output the target voltage signal;

[0017] The output switching module is further used to transmit the first voltage signal to the step-down unit or transmit the second voltage signal to the step-up unit.

[0018] Optionally, the boost unit includes: an LTC7804 chip;

[0019] The input end of the LTC7804 chip is connected to the output end of the output switching module, and the output end of the LTC7804 chip is used to output the target voltage signal.

[0020] Optionally, the voltage reduction unit comprises:

[0021] LM3150 chip;

[0022] The input end of the LM3150 chip is connected to the output end of the output switching module, and the output end of the LM3150 chip is used to output the target voltage signal.

[0023] Optionally, the output selection circuit further includes: a communication module;

[0024] The communication module is connected to the main control chip and also connected to the terminal;

[0025] The communication module is used to receive the setting signal output by the terminal and output the setting signal to the main control chip;

[0026] The main control chip is used to output a selection signal to the output switching module when receiving the setting signal.

[0027] Optionally, the output selection circuit further includes: a power supply module;

[0028] The input end of the power supply module is connected to the external DC power supply, and the output end is connected to the main control chip and the communication module;

[0029] The power supply module is used to convert the first voltage signal into a power supply signal for the main control chip and the communication module for power supply.

[0030] Optionally, the power supply module includes: a power protection unit and a voltage conversion unit;

[0031] The input end of the power protection unit is connected to the external DC power supply, the output end of the power protection unit is connected to the input end of the voltage conversion unit, and the output end of the voltage conversion unit is connected to the main control chip and the communication module;

[0032] The power supply protection unit is used to disconnect the circuit between the external DC power supply and the voltage conversion unit when receiving the abnormal first voltage signal sent by the external DC power supply;

[0033] The voltage conversion unit is used to perform voltage conversion processing on the first voltage signal to generate a power supply signal, and transmit the power supply signal to the main control chip and the communication module.

[0034] In addition, to achieve the above-mentioned purpose, the utility model also provides a DC UPS power supply, and the DC UPS power supply includes: the above-mentioned output selection circuit.

[0035] The technical solution of the utility model proposes an output selection circuit and a DC UPS power supply. The output selection circuit includes: a main control chip, an output switching module and a voltage regulating module; the first end of the output switching module is connected to an external DC power supply, the second end is connected to the battery of the DC UPS power supply, the third end is connected to the output end of the main control chip, and the fourth end is connected to the voltage regulating module; the output switching module is used to receive the selection signal of the main control chip, and select to transmit the first voltage signal of the external DC power supply or the second voltage signal of the battery to the voltage regulating module; the voltage regulating module is used to adjust the first voltage signal or the second voltage signal to the target voltage signal for output. The output switching module is controlled by the main control chip to output the voltage of the external DC power supply or the voltage of the battery, and the output voltage is converted into a target voltage signal using the voltage regulating module, so that the UPS has multi-channel output capability as a backup power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0037] Figure 1 It is a module schematic diagram of the first embodiment of the output selection circuit of the utility model;

[0038] Figure 2 It is a module schematic diagram of the second embodiment of the output selection circuit of the utility model;

[0039] Figure 3 This is a circuit connection diagram of a conduction control unit in the second embodiment of the output selection circuit of the utility model;

[0040] Figure 4 It is a structural schematic diagram of a third embodiment of the output selection circuit of the utility model;

[0041] Figure 5 This is a functional structure diagram of the DC UPS power supply proposed by the utility model.

[0042] Description of Figure Numbers:

[0043] Label name Label name 10 Main control chip 302 Step-down unit 20 Output switching module 601 Power protection unit 30 Voltage Regulator Module 602 Voltage conversion unit 40 Charging management module R1, R2 The first and second resistors 50 Communication Module Q1, Q2 The first and second switch tubes 60 Power supply module D1 diode 201 Conductivity control unit K1 Relay 301 Boost unit

[0044] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0045] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0046] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0047] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0048] In addition, the descriptions of "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0049] Reference Figure 1 , Figure 1 The module diagram of the first embodiment of the output selection circuit of the utility model is shown in FIG. The utility model provides the first embodiment of the output selection circuit.

[0050] In this embodiment, the output selection circuit includes: a main control chip 10, an output switching module 20 and a voltage regulating module 30. The first end of the output switching module 20 is connected to an external DC power supply, the second end is connected to a battery of a DC UPS power supply, the third end is connected to the output end of the main control chip 10, and the fourth end is connected to the voltage regulating module 30.

[0051] It should be noted that the first end of the output switching module 20 is connected to the external DC power supply, the second end is connected to the battery of the DC UPS power supply, the third end is connected to the output end of the main control chip 10, and the fourth end is connected to the voltage regulation module 30; the output switching module 20 can be used to receive the selection signal of the main control chip 10, and select to transmit the first voltage signal of the external DC power supply or the second voltage signal of the battery to the voltage regulation module 30; the voltage regulation module 30 can be used to adjust the first voltage signal or the second voltage signal to the target voltage signal for output.

[0052] It should be understood that the main control chip 10 can be an electronic device with data processing capabilities, which can realize data storage, processing and transmission functions by means of preset programs. The internal part can be a microcomputer system integrated with a central processing unit (CPU), a random access memory (RAM) and a read-only memory (ROM). For example: a microcontroller unit (MCU) or a CPU chip. In this embodiment, an STM32F103 chip can be selected as the main control chip.

[0053] Furthermore, the first voltage signal may be a 24V DC signal from an external DC power supply. The second DC signal may be a 12V DC signal from a battery used for energy storage in a UPS. The target voltage signal may be a DC signal capable of adjusting the output voltage.

[0054] The selection signal may be an electrical signal generated by the main control chip 10 for controlling the state of the output switching module 20. The output switching module 20 may parse the selection signal upon receiving the selection signal to obtain a first voltage signal of an external DC power supply to be output or a second voltage signal of a level to be output. The selection signal may be controlled by outputting multiple signals to the output switching module 20, or by outputting a single signal in a coded form.

[0055] It should be noted that the voltage regulating module 30 can perform voltage regulation on the received first voltage signal and the second voltage signal by means of a boost circuit or a buck circuit to obtain the target voltage signal that meets the requirements.

[0056] This embodiment proposes an output selection circuit. The output selection circuit includes: a main control chip, an output switching module and a voltage regulating module; the first end of the output switching module is connected to an external DC power supply, the second end is connected to a battery of a DC UPS power supply, the third end is connected to the output end of the main control chip, and the fourth end is connected to the voltage regulating module; the output switching module is used to receive a selection signal from the main control chip, and select to transmit the first voltage signal of the external DC power supply or the second voltage signal of the battery to the voltage regulating module; the voltage regulating module is used to adjust the first voltage signal or the second voltage signal to a target voltage signal for output. The output switching module is controlled by the main control chip to output the voltage of the external DC power supply or the voltage of the battery, and the voltage regulating module is used to convert the output voltage into a target voltage signal, so that the UPS has multi-channel output capability as a backup power supply.

[0057] Reference Figure 2 , Figure 2 The second embodiment of the output selection circuit of the present invention is a schematic diagram of a module of the second embodiment of the output selection circuit of the present invention. The second embodiment of the output selection circuit of the present invention is proposed based on the first embodiment of the output selection circuit mentioned above.

[0058] In this embodiment, the output switching module 20 includes: four conduction control units 201; the control end of each conduction control unit 201 is connected to the main control chip 10, the input end of each conduction control unit 201 is connected to its corresponding battery or external DC power supply, and the output end of each conduction control unit 201 is connected to the voltage regulation module.

[0059] It should be noted that the conduction control unit 201 can be used to receive a selection signal from the main control chip 10 to conduct the circuit between the corresponding battery or external DC power supply and the voltage regulation module 30 .

[0060] It should be understood that two of the four conduction control units 201 are connected to the external DC power supply to receive the first voltage signal of the external DC power supply, and the other two are connected to the battery to receive the second voltage signal of the battery.

[0061] Reference Figure 3 , Figure 3 This is a circuit connection diagram of the conduction control unit in the second embodiment of the output selection circuit of the utility model. Each of the conduction control units includes: a first resistor R1, a second resistor R2, a first switch tube Q1, a second switch tube Q2, a diode D1 and a relay K1.

[0062] It should be noted that the first end of the relay K1 is connected to the corresponding battery or external DC power supply, the second end of the relay K1 is connected to the voltage regulation module 30, the control end of the first switch tube Q1 is connected to the first end of the first resistor R1 and the main control chip 10, the input end of the first switch tube Q1 is connected to the first end of the second resistor R2 and the control end of the second switch tube Q2, the output ends of the first switch tube Q1 and the second switch tube Q2 are both grounded, the second end of the first resistor R1 is connected to the second end of the second resistor R2, the cathode of the diode D1 and the third end of the relay K1, and the input end of the second switch tube Q2 is connected to the anode of the diode D1 and the fourth end of the relay K1.

[0063] It should be understood that the selection signal sent by the main control chip 10 can be controlled by outputting multiple signals to each of the conduction control units 201. When the control end of the first switch tube Q1 in each of the conduction control units 201 receives the selection signal, the relay will conduct the conduction loop between the first end and the second end.

[0064] Furthermore, the voltage regulating module 30 includes: a boost unit 301 and a buck unit 302. The input end of the boost unit 301 is connected to the output end of the output switching module 20, the output end of the boost unit 301 is used to output the target voltage signal, the input end of the buck unit 302 is connected to the output end of the output switching module, and the output end of the buck unit 302 is used to output the target voltage signal.

[0065] It should be noted that the output switching module 20 can also be used to transmit the first voltage signal to the voltage step-down unit 302 or transmit the second voltage signal to the voltage step-up unit 301 .

[0066] It should be understood that the first voltage signal transmitted to the step-down unit 302 will be stepped down from the voltage amplitude of 24V to 12V for output, and the second voltage signal transmitted to the step-up unit 301 will be stepped up from the voltage amplitude of 12V to 24V for output. In this way, when the external DC power supply is used, the output of two voltage amplitudes of 12V and 24V can be obtained, and when the external DC power supply is disconnected and only the UPS battery is used for power supply, the output of two voltage amplitudes of 12V and 24V can also be obtained.

[0067] Furthermore, the boost unit 301 includes: an LTC7804 chip; an input end of the LTC7804 chip is connected to an output end of the output switching module, and the output end of the LTC7804 chip is used to output the target voltage signal.

[0068] It should be noted that the LTC7804 chip can be a synchronous boost DC switching regulator chip, which can build a boost architecture by setting up peripheral circuits (the specific circuit construction method can refer to the LTC7804 chip data sheet), thereby converting a 12V input voltage into a 24V output voltage.

[0069] Furthermore, the voltage reduction unit 302 includes: an LM3150 chip; an input end of the LM3150 chip is connected to an output end of the output switching module, and the output end of the LM3150 chip is used to output the target voltage signal.

[0070] It should be noted that the LM3150 chip can be a buck power controller chip, which can build a buck architecture by setting up peripheral circuits (the specific circuit construction method can refer to the LM3150 chip data sheet), thereby converting a 24V input voltage into a 12V output voltage.

[0071] Furthermore, the external DC power supply inputs the first voltage signal to the output selection circuit through an input interface, and the output selection circuit further includes: a charging management module 40. The input end of the charging management module 40 is connected to the input interface, and the output end of the charging management module 40 is connected to the battery.

[0072] It should be noted that the charging management module 40 can charge the battery when receiving the first voltage signal from the external DC power supply.

[0073] It should be understood that the charging management module 40 includes: a CN3717 chip. The CN3717 chip can be a buck mode battery charging management circuit chip that can automatically manage the charging of the battery. It has a constant current output effect, and can build a charging management architecture by setting a peripheral circuit (the specific circuit construction method can refer to the CN3717 chip data manual), thereby realizing the charging management of converting the 24V input voltage into a 12V battery voltage.

[0074] In this embodiment, four conduction control units are provided, the control end of each conduction control unit is connected to the main control chip, the input end of each conduction control unit is connected to the corresponding battery or external DC power supply, and the output end of each conduction control unit is connected to the voltage regulation module. It is used to receive the selection signal of the main control chip, conduct the loop between the corresponding battery or external DC power supply and the voltage regulation module. It realizes the selection of the first voltage signal of the external DC power supply or the second voltage signal of the battery. And by providing a boost unit and a buck unit, the output of two voltage amplitudes of 12V and 24V is obtained. This enables the UPS to have multi-channel output capability as a backup power supply.

[0075] Reference Figure 4 , Figure 4 The third embodiment of the output selection circuit of the present invention is a schematic diagram of the structure of the third embodiment of the output selection circuit of the present invention. Based on the above embodiments of the output selection circuit, the third embodiment of the output selection circuit of the present invention is proposed.

[0076] In this embodiment, the output selection circuit further includes: a communication module 50; the communication module 50 is connected to the main control chip 10 and also connected to a terminal.

[0077] It should be noted that the communication module 50 can be used to receive the setting signal output by the terminal and output the setting signal to the main control chip 10; the main control chip 10 can be used to output a selection signal to the output switching module 20 when receiving the setting signal.

[0078] It should be understood that the terminal can be used by the user to control the power status of the UPS, monitor the health of the battery, remotely set the UPS discharge and other remote control functions, which are not limited in this embodiment. The setting signal is a communication signal sent by the terminal to control the UPS discharge mode.

[0079] Furthermore, the communication module 50 may be a 4G communication transmission module, which communicates with the main control chip 10 via a serial port to transmit data required for 4G communication.

[0080] Furthermore, the output selection circuit further includes: a power supply module 60 ; an input end of the power supply module 60 is connected to the external DC power supply, and an output end of the power supply module 60 is connected to the main control chip 10 and the communication module 50 .

[0081] It should be noted that the power supply module can be used to convert the first voltage signal into a power supply signal for the main control chip and the communication module for power supply. The power supply signal for the main control chip and the communication module should be 5V.

[0082] Further, the power supply module 60 includes: a power protection unit 601 and a voltage conversion unit 602; the input end of the power protection unit 601 is connected to the external DC power supply, the output end of the power protection unit 601 is connected to the input end of the voltage conversion unit 602, and the output end of the voltage conversion unit 602 is connected to the main control chip 10 and the communication module 50;

[0083] It should be noted that the power protection unit 601 can be used to disconnect the loop between the external DC power supply and the voltage conversion unit 602 when receiving the first abnormal voltage signal emitted by the external DC power supply; the voltage conversion unit 602 can be used to perform voltage conversion processing on the first voltage signal, generate a power supply signal, and transmit the power supply signal to the main control chip 10 and the communication module 50.

[0084] It should be understood that the power protection unit 601 can disconnect the external DC power supply when the external DC power supply has a fault such as overvoltage, overcurrent, overheating, and short circuit, so as to ensure the safe operation of the UPS. The power protection unit 601 may include: a fuse and a switch tube, both of which are arranged between the external DC power supply and the voltage conversion unit.

[0085] Furthermore, the voltage conversion unit 602 can convert the input 24V voltage into a 5V supply voltage. Including: LTC3824 chip. Wherein, the LTC3824 chip can be a DC buck controller chip, which can build a buck architecture by setting a peripheral circuit (the specific circuit construction method can refer to the LTC3824 chip data manual), thereby realizing the conversion of the 24V input voltage into a 5V output voltage.

[0086] In this embodiment, a communication module is provided. The communication module is connected to the main control chip and also to the terminal; the communication module is used to receive the setting signal output by the terminal and output the setting signal to the main control chip; the main control chip is used to output a selection signal to the output switching module when receiving the setting signal. The remote control function of the UPS is realized. A power supply module is provided; the input end of the power supply module is connected to the external DC power supply, and the output end is connected to the main control chip and the communication module; the power supply module is used to convert the first voltage signal into a power supply signal for the main control chip and the communication module for power supply. The UPS can have a more stable operating environment and extend the service life of the equipment. The UPS has the ability to be remotely controlled and output multiple DC voltages.

[0087] In addition, the embodiment of the utility model also provides a DC UPS power supply, and the DC UPS power supply includes the above-mentioned output selection circuit. Figure 5 , Figure 5 This is a functional structure diagram of the DC UPS power supply proposed by the utility model.

[0088] Since the DC UPS power supply adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0089] The above description is only a preferred embodiment of the utility model, and does not limit the patent scope of the utility model. All equivalent structural changes made by using the contents of the utility model specification and drawings under the utility model concept, or directly / indirectly used in other related technical fields are included in the patent protection scope of the utility model.

Claims

1. An output selection circuit, characterized in that: The output selection circuit is applied to a DC UPS power supply, and the output selection circuit comprises: a main control chip, an output switching module and a voltage regulating module; The first end of the output switching module is connected to the external DC power supply, the second end is connected to the battery of the DC UPS power supply, the third end is connected to the output end of the main control chip, and the fourth end is connected to the voltage regulation module; The output switching module is used to receive the selection signal of the main control chip and select to transmit the first voltage signal of the external DC power supply or the second voltage signal of the battery to the voltage regulation module; The voltage regulating module is used to regulate the first voltage signal or the second voltage signal to a target voltage signal for output.

2. The output selection circuit according to claim 1, characterized in that: The output switching module includes: four conduction control units; The control end of each conduction control unit is connected to the main control chip, the input end of each conduction control unit is connected to the corresponding battery or external DC power supply, and the output end of each conduction control unit is connected to the voltage regulation module; The conduction control unit is used to receive a selection signal from the main control chip and conduct the circuit between the corresponding battery or external DC power supply and the voltage regulation module.

3. The output selection circuit according to claim 2, characterized in that: Each of the conduction control units comprises: a first resistor, a second resistor, a first switch tube, a second switch tube, a diode and a relay; The first end of the relay is connected to the corresponding battery or external DC power supply, the second end of the relay is connected to the voltage regulation module, the control end of the first switch tube is connected to the first end of the first resistor and the main control chip at the same time, the input end of the first switch tube is connected to the first end of the second resistor and the control end of the second switch tube at the same time, the output ends of the first switch tube and the second switch tube are both grounded, the second end of the first resistor is connected to the second end of the second resistor, the cathode of the diode and the third end of the relay at the same time, and the input end of the second switch tube is connected to the anode of the diode and the fourth end of the relay at the same time.

4. The output selection circuit according to claim 1, characterized in that: The voltage regulation module includes: a boost unit and a buck unit; The input end of the boost unit is connected to the output end of the output switching module, the output end of the boost unit is used to output the target voltage signal, the input end of the buck unit is connected to the output end of the output switching module, and the output end of the buck unit is used to output the target voltage signal; The output switching module is further used to transmit the first voltage signal to the step-down unit or transmit the second voltage signal to the step-up unit.

5. The output selection circuit according to claim 4, characterized in that: The boost unit includes: an LTC7804 chip; The input end of the LTC7804 chip is connected to the output end of the output switching module, and the output end of the LTC7804 chip is used to output the target voltage signal.

6. The output selection circuit according to claim 4, characterized in that: The step-down unit comprises: LM3150 chip; The input end of the LM3150 chip is connected to the output end of the output switching module, and the output end of the LM3150 chip is used to output the target voltage signal.

7. The output selection circuit according to claim 6, characterized in that: The output selection circuit further includes: a communication module; The communication module is connected to the main control chip and also connected to the terminal; The communication module is used to receive the setting signal output by the terminal and output the setting signal to the main control chip; The main control chip is used to output a selection signal to the output switching module when receiving the setting signal.

8. The output selection circuit according to claim 7, characterized in that: The output selection circuit further includes: a power supply module; The input end of the power supply module is connected to the external DC power supply, and the output end is connected to the main control chip and the communication module; The power supply module is used to convert the first voltage signal into a power supply signal for the main control chip and the communication module for power supply.

9. The output selection circuit according to claim 8, characterized in that: The power supply module includes: a power protection unit and a voltage conversion unit; The input end of the power protection unit is connected to the external DC power supply, the output end of the power protection unit is connected to the input end of the voltage conversion unit, and the output end of the voltage conversion unit is connected to the main control chip and the communication module; The power supply protection unit is used to disconnect the circuit between the external DC power supply and the voltage conversion unit when receiving the abnormal first voltage signal sent by the external DC power supply; The voltage conversion unit is used to perform voltage conversion processing on the first voltage signal to generate a power supply signal, and transmit the power supply signal to the main control chip and the communication module.

10. A DC UPS power supply, characterized in that: The DC UPS power supply comprises the output selection circuit as described in any one of claims 1-9.

Images