Charging circuit and electronic equipment

Abstract

A charging circuit and an electronic device belong to the technical field of charging, a control circuit outputs a first enable signal when a battery voltage is less than a first preset voltage, and outputs a second enable signal when the battery voltage is greater than or equal to a second preset voltage; the first conversion circuit is used for converting accessed first input direct current into first charging voltage based on a first enable signal; the power management circuit converts the accessed second input direct current into a second charging voltage based on a second enable signal; the first energy storage circuit performs charging according to the first charging voltage or the second charging voltage, wherein the first preset voltage is smaller than the second preset voltage; therefore, the possibility that the load cannot be normally used due to the fact that the power management circuit is in the pre-charging stage and the output pre-charging current is small is avoided, charging can be carried out according to the first charging voltage without disconnecting the post-stage load, normal use of the vehicle-mounted electronic tag is not affected, and the charging speed is increased.

Description

Technical Field

[0001] The present application belongs to the field of charging technology, and in particular relates to a charging circuit and an electronic device. Background Art

[0002] Rechargeable on-board electronic tags charge the battery capacitor through a charging management chip. In order to extend the life of the battery capacitor, the charging process is designed through the charging management chip. When the battery capacitor is very low, the pre-charging stage will be started first to extend the life of the battery capacitor. The general pre-charging current is 5% to 10% of the charging current, which is about 5mA to 10mA. General on-board electronic tags have light-emitting diodes or buzzers, and a user interface will be displayed during charging. When the vehicle is driving on the road, 5.8G communication will be performed, resulting in power consumption greater than or close to the pre-charging current, which will cause the following problems: 1. When the power consumption is greater than the pre-charging current, the battery capacitor will never be fully charged; 2. When the power consumption is close to the pre-charging current, the actual amount of power supplied to the battery capacitor is very small, and it takes a long time for the battery capacitor to cross the pre-charging stage, usually more than 60 minutes.

[0003] At present, most of the on-board electronic tags solve the problem of long charging time by detecting the battery capacitor voltage during charging. If it is too low, the downstream load is disconnected, that is, all user interfaces and transaction functions are closed, which brings inconvenience to users.

[0004] Therefore, the relevant charging circuit has the defect that it cannot reduce the pre-charging time while using the load normally. Utility Model Content

[0005] The purpose of the present application is to provide a charging circuit and an electronic device, aiming to solve the problem that the related charging circuit cannot reduce the pre-charging time while using the load normally.

[0006] An embodiment of the present application provides a charging circuit connected to a first energy storage circuit for outputting a battery voltage, comprising:

[0007] The control circuit is configured to output a first enable signal when the battery voltage is less than a first preset voltage, and output a second enable signal when the battery voltage is greater than or equal to a second preset voltage;

[0008] a first conversion circuit, connected to the control circuit and the first energy storage circuit, configured to receive a first input direct current and convert the first input direct current into a first charging voltage based on the first enable signal;

[0009] a power management circuit connected to the control circuit and the first energy storage circuit, configured to receive a second input direct current and convert the second input direct current into a second charging voltage based on the second enable signal;

[0010] The first energy storage circuit is further configured to be charged according to the first charging voltage or the second charging voltage;

[0011] The first preset voltage is smaller than the second preset voltage.

[0012] In one embodiment, the power management circuit includes:

[0013] a switch circuit, connected to the control circuit, configured to access the second input direct current and transmit the second input direct current based on the second enable signal;

[0014] The charging management circuit is connected to the switch circuit and the first energy storage circuit, and is configured to convert the second input direct current into the second charging voltage.

[0015] In one of the embodiments, the switch circuit includes a first transistor, a third resistor and a fourth resistor;

[0016] The emitter of the first transistor and the first end of the fourth resistor serve together as the second input DC input terminal of the switch circuit to access the second input DC; the base of the first transistor is connected to the first end of the third resistor, and the second end of the third resistor and the second end of the fourth resistor serve together as the second enable signal input terminal of the switch circuit, connected to the control circuit to input the second enable signal; the collector of the first transistor serves as the second input DC output terminal of the switch circuit, connected to the charging management circuit to output the second input DC.

[0017] In one embodiment, the charging management circuit includes a battery charger, a fourth diode and a fifth resistor;

[0018] The anode of the fourth diode serves as the second DC input terminal of the charging management circuit and is connected to the switch circuit to access the second DC input; the cathode of the fourth diode is connected to the charging power input terminal of the battery charger, the maximum charging current setting and the charging prohibition input terminal of the battery charger are connected to the first end of the fifth resistor, the ground terminal of the battery charger, the second end of the fifth resistor, the charging voltage setting of the battery charger and the intermediate voltage balance terminal of the massive capacitor are connected to the power ground; the charging output terminal of the battery charger serves as the second charging voltage output terminal of the charging management circuit and is connected to the first energy storage circuit to output the second charging voltage.

[0019] In one embodiment, it also includes:

[0020] a photocell circuit configured to convert received light energy into a third input direct current;

[0021] a second conversion circuit connected to the photocell circuit and the first energy storage circuit and configured to convert the third input direct current into a third charging voltage;

[0022] The first energy storage circuit is further configured to be charged according to the third charging voltage.

[0023] In one embodiment, it also includes:

[0024] a second energy storage circuit configured to output a fourth input direct current;

[0025] a third conversion circuit, connected to the second energy storage circuit and the first energy storage circuit, configured to convert the fourth input direct current into a fourth charging voltage;

[0026] The first energy storage circuit is further configured to be charged according to the fourth charging voltage.

[0027] In one embodiment, the first input DC power includes a USB voltage and an external voltage;

[0028] The charging circuit further comprises:

[0029] A USB interface configured to transfer the USB voltage;

[0030] A first interface configured to transfer the external voltage;

[0031] The first conversion circuit is specifically configured to access the USB voltage and / or the external voltage, and convert the USB voltage and / or the external voltage into a first charging voltage based on the first enable signal.

[0032] In one embodiment, it also includes:

[0033] a level conversion circuit, connected to the control circuit and the first conversion circuit, and performing level conversion on the first enable signal;

[0034] The first conversion circuit is specifically configured to access the first input direct current and convert the first input direct current into a first charging voltage based on the first enable signal after level conversion.

[0035] In one embodiment, the control circuit includes a microprocessor;

[0036] The first general input and output terminal of the microprocessor serves as the first enable signal output terminal of the control circuit, and is connected to the first conversion circuit to output the first enable signal; the second general input and output terminal of the microprocessor serves as the second enable signal output terminal of the control circuit, and is connected to the power management circuit to output the second enable signal; the third general input and output terminal of the microprocessor serves as the battery voltage input terminal of the third enable signal of the control circuit, and is connected to the first energy storage circuit to input the battery voltage.

[0037] In one embodiment, the first conversion circuit includes a first voltage stabilizing chip, a first diode, a second diode, a third diode, a first resistor and a second resistor;

[0038] The anode of the first diode serves as the first first input DC power input terminal of the first conversion circuit to access the first first input DC power; the anode of the second diode serves as the second first input DC power input terminal of the first conversion circuit to access the second first input DC power; the cathode of the first diode, the cathode of the second diode, the first end of the first resistor and the input terminal of the first voltage stabilizing chip are connected, and the first end of the second resistor serves as the first enable signal input terminal of the first conversion circuit and is connected to the control circuit to input the first enable signal; the second end of the first resistor, the second end of the second resistor and the enable input terminal of the first voltage stabilizing chip are connected in common, the output terminal of the first voltage stabilizing chip is connected to the anode of the third diode, and the cathode of the third diode serves as the first charging voltage output terminal of the first conversion circuit and is connected to the first energy storage circuit to output the first charging voltage; the ground terminal of the first voltage stabilizing chip is connected to the power ground.

[0039] An embodiment of the present application further provides an electronic device, which includes the above-mentioned charging circuit.

[0040] Compared with the prior art, the embodiments of the present application have the following beneficial effects: the control circuit outputs a first enable signal when the battery voltage is less than a first preset voltage, and outputs a second enable signal when the battery voltage is greater than or equal to a second preset voltage; the first conversion circuit converts the connected first input DC power into a first charging voltage based on the first enable signal; the power management circuit converts the connected second input DC power into a second charging voltage based on the second enable signal; the first energy storage circuit is charged according to the first charging voltage or the second charging voltage, wherein the first preset voltage is less than the second preset voltage; therefore, the possibility that the load cannot be used normally due to the small pre-charging current output by the power management circuit in the pre-charging stage is avoided, so that charging can be performed according to the first charging voltage without disconnecting the subsequent load, thereby not affecting the normal use of the vehicle-mounted electronic tag and improving the charging speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical application in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 A schematic diagram of a charging circuit provided in one embodiment of the present application;

[0043] Figure 2 Another structural schematic diagram of a charging circuit provided in an embodiment of the present application;

[0044] Figure 3 Another structural schematic diagram of a charging circuit provided in an embodiment of the present application;

[0045] Figure 4 Another structural schematic diagram of a charging circuit provided in an embodiment of the present application;

[0046] Figure 5 Another structural schematic diagram of a charging circuit provided in an embodiment of the present application;

[0047] Figure 6 A partial exemplary circuit schematic diagram of a current output circuit in a charging circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0048] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0049] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0050] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0051] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0052] Figure 1 The structure diagram of the charging circuit 10 provided in one embodiment of the present application is shown. For the convenience of description, only the part related to the present embodiment is shown, which is described in detail as follows:

[0053] The charging circuit 10 is connected to a first energy storage circuit 20 for outputting a battery voltage, and includes a control circuit 100 , a first conversion circuit 200 and a power management circuit 300 .

[0054] The control circuit 100 is configured to output a first enable signal when the battery voltage is less than a first preset voltage, and to output a second enable signal when the battery voltage is greater than or equal to a second preset voltage.

[0055] The first conversion circuit 200 is connected to the control circuit 100 and the first energy storage circuit 20, and is configured to receive a first input direct current and convert the first input direct current into a first charging voltage based on a first enable signal.

[0056] The power management circuit 300 is connected to the control circuit 100 and the first energy storage circuit 20, and is configured to receive the second input direct current and convert the second input direct current into a second charging voltage based on a second enable signal.

[0057] The first energy storage circuit 20 is further configured to be charged according to the first charging voltage or the second charging voltage.

[0058] The first preset voltage is smaller than the second preset voltage.

[0059] When the battery voltage is less than the first preset voltage through the first conversion circuit 200, the first energy storage circuit 20 can be charged according to the first charging voltage without disconnecting the subsequent load, thereby not affecting the normal use of the vehicle-mounted electronic tag and improving the charging speed.

[0060] By way of example and not limitation, Figure 2 As shown, the power management circuit 300 includes a switch circuit 310 and a charging management circuit 320 .

[0061] The switch circuit 310 is connected to the control circuit 100 and configured to receive the second input direct current and transmit the second input direct current based on the second enable signal.

[0062] The charging management circuit 320 is connected to the switch circuit 310 and the first energy storage circuit 20, and is configured to convert the second input direct current into a second charging voltage.

[0063] The switch circuit 310 controls the input and disconnection of the second input direct current, so that the charging management circuit 320 charges the battery when the battery voltage is greater than the second preset voltage, thereby ensuring a stable and efficient charging process.

[0064] By way of example and not limitation, Figure 3 As shown, the charging circuit 10 further includes a photovoltaic circuit 400 and a second conversion circuit 500 .

[0065] The photocell circuit 400 is configured to convert received light energy into a third input direct current.

[0066] The second conversion circuit 500 is connected to the photovoltaic circuit 400 and the first energy storage circuit 20, and is configured to convert the third input direct current into a third charging voltage.

[0067] The first energy storage circuit 20 is further configured to be charged according to a third charging voltage.

[0068] The photocell circuit 400 uses light to supplement power, thereby improving the usability of the product.

[0069] By way of example and not limitation, Figure 4 As shown, a second energy storage circuit 600 and a third conversion circuit 700 are also included.

[0070] The second energy storage circuit 600 is configured to output a fourth input direct current.

[0071] The third conversion circuit 700 is connected to the second energy storage circuit 600 and the first energy storage circuit 20, and is configured to convert the fourth input direct current into a fourth charging voltage.

[0072] The first energy storage circuit 20 is further configured to be charged according to a fourth charging voltage.

[0073] The second energy storage circuit 600 allows the product to be used normally for a long time without charging before leaving the factory, thus enriching the functions of the product.

[0074] The first input direct current includes a universal serial bus (USB) voltage and an external voltage.

[0075] The charging circuit 10 further includes a USB interface and a first interface.

[0076] USB interface, configured to transfer USB voltage.

[0077] The first interface is configured to transfer an external voltage.

[0078] The first conversion circuit 200 is specifically configured to receive a USB voltage and / or an external voltage, and convert the USB voltage and / or the external voltage into a first charging voltage based on a first enable signal.

[0079] The USB interface and the first interface broaden the use scope of the charging circuit 10 and improve the adaptability of the circuit.

[0080] By way of example and not limitation, Figure 5 As shown, the charging circuit 10 further includes a level conversion circuit 800 .

[0081] The level conversion circuit 800 is connected to the control circuit 100 and the first conversion circuit 200, and performs level conversion on the first enable signal.

[0082] The first conversion circuit 200 is specifically configured to receive a first input direct current and convert the first input direct current into a first charging voltage based on a first enable signal after level conversion.

[0083] The compatibility of the charging circuit 10 is improved by the level conversion circuit 800 .

[0084] Figure 6 A partial exemplary circuit structure of the charging circuit 10 provided in an embodiment of the present application is shown. For the sake of convenience, only the part related to the embodiment of the present application is shown, which is described in detail as follows:

[0085] The switch circuit 310 includes a first transistor U3 , a third resistor R3 , and a fourth resistor R4 .

[0086] The emitter E of the first transistor U3 and the first end of the fourth resistor R4 serve together as the second input DC input terminal of the switch circuit 310 to connect the second input DC power; the base B of the first transistor U3 is connected to the first end of the third resistor R3, and the second end of the third resistor R3 and the second end of the fourth resistor R4 serve together as the second enable signal input terminal of the switch circuit 310, which is connected to the control circuit 100 to input the second enable signal; the collector C of the first transistor U3 serves as the second input DC output terminal of the switch circuit 310, which is connected to the charging management circuit 320 to output the second input DC power.

[0087] Using transistors as switches has fast switching speed and low loss.

[0088] The charging management circuit 320 includes a battery charger U4 , a fourth diode D4 , and a fifth resistor R5 .

[0089] The anode of the fourth diode D4 is connected to the switch circuit 310 as the second input DC power input terminal of the charging management circuit 320 to access the second input DC power; the cathode of the fourth diode D4 is connected to the charging power input terminal VIN of the battery charger U4, the maximum charging current setting and the charging prohibition input terminal IREF of the battery charger U4 are connected to the first end of the fifth resistor R5, the ground terminal GND of the battery charger U4, the second end of the fifth resistor R5, the charging voltage setting of the battery charger U4 and the intermediate voltage balance terminal F of the massive capacitor are connected to the power ground; the charging output terminal BAT of the battery charger U4 is connected to the first energy storage circuit 20 as the second charging voltage output terminal of the charging management circuit 320 to output the second charging voltage.

[0090] The charging manager adjusts the output voltage and current of the charging power supply to ensure that the battery is charged within an acceptable range, thereby improving the safety of charging.

[0091] The control circuit 100 includes a microprocessor U1.

[0092] The first universal input-output terminal P1.0 of the microprocessor U1 serves as the first enable signal output terminal of the control circuit 100, and is connected to the first conversion circuit 200 to output a first enable signal; the second universal input-output terminal P1.1 of the microprocessor U1 serves as the second enable signal output terminal of the control circuit 100, and is connected to the power management circuit 300 to output a second enable signal; the third universal input-output terminal P1.2 of the microprocessor U1 serves as the battery voltage input terminal of the control circuit 100, and is connected to the first energy storage circuit 20 to input the battery voltage.

[0093] The circuit is simple and reliable.

[0094] The first conversion circuit 200 includes a first voltage stabilizing chip U2 , a first diode D1 , a second diode D2 , a third diode D3 , a first resistor R1 , and a second resistor R2 .

[0095] The anode of the first diode D1 serves as the first first input DC input terminal of the first conversion circuit 200 to access the first first input DC power; the anode of the second diode D2 serves as the second first input DC input terminal of the first conversion circuit 200 to access the second first input DC power; the cathode of the first diode D1, the cathode of the second diode D2, the first end of the first resistor R1 and the input terminal VIN of the first voltage regulator chip U2 are connected, and the first end of the second resistor R2 serves as the first enable signal input terminal of the first conversion circuit 200 and is connected to the control circuit 100 to input the first enable signal; the second end of the first resistor R1, the second end of the second resistor R2 and the enable input terminal ON of the first voltage regulator chip U2 are connected in common, the output terminal OUT of the first voltage regulator chip U2 is connected to the anode of the third diode D3, and the cathode of the third diode D3 serves as the first charging voltage output terminal of the first conversion circuit 200 and is connected to the first energy storage circuit 20 to output the first charging voltage; the ground terminal GND of the first voltage regulator chip U2 is connected to the power ground.

[0096] The first voltage stabilizing chip U2 is used to realize voltage conversion, which is low in cost.

[0097] The second conversion circuit 500 includes a second voltage stabilizing chip U5 , a fifth diode D5 , and a sixth diode D6 .

[0098] The anode of the sixth diode D6 serves as the third input DC power input terminal of the second conversion circuit 500, and is connected to the photocell circuit 400 to access the third input DC power; the cathode of the sixth diode D6 is connected to the input terminal VIN of the second voltage stabilizing chip U5, the output terminal OUT of the second voltage stabilizing chip U5 is connected to the anode of the fifth diode D5, the cathode of the fifth diode D5 serves as the third charging voltage output terminal of the second conversion circuit 500, and is connected to the first energy storage circuit 20 to output the third charging voltage; the ground terminal GND of the second voltage stabilizing chip U5 is connected to the power ground.

[0099] The third conversion circuit 700 includes a third voltage stabilizing chip U6, a seventh diode D7 and an eighth diode D8.

[0100] The input terminal VIN of the third voltage stabilizing chip U6 and the positive electrode of the eighth diode D8 serve together as the fourth input DC power input terminal of the third conversion circuit 700, and are connected to the second energy storage circuit 600 to access the fourth input DC power; the output terminal OUT of the third voltage stabilizing chip U6, the negative electrode of the eighth diode D8 and the positive electrode of the seventh diode D7 are connected, and the negative electrode of the seventh diode D7 serves as the fourth charging voltage output terminal of the third conversion circuit 700, and is connected to the first energy storage circuit 20 to output the fourth charging voltage; the ground terminal GND of the third voltage stabilizing chip U6 is connected to the power ground.

[0101] The level conversion circuit 800 includes a second transistor U7 , a fifth resistor R5 , and a sixth resistor R6 .

[0102] The first end of the fifth resistor R5 and the first end of the sixth resistor R6 serve together as the first enable signal input end of the level conversion circuit 800, and are connected to the control circuit 100 to receive the first enable signal; the second end of the sixth resistor R6 and the emitter E of the second transistor U7 serve together as the first input DC input end of the level conversion circuit 800 to receive the first input DC; the second end of the fifth resistor R5 is connected to the base B of the second transistor U7, and the collector C of the second transistor U7 serves as the first enable signal output end after level conversion of the level conversion circuit 800, and is connected to the first conversion circuit 200 to output the first enable signal after level conversion.

[0103] The following is a combination of working principles Figure 6 As shown for further explanation:

[0104] When there is light, the photocell circuit 400 converts the received light energy into a third input direct current, and outputs it to the positive electrode of the sixth diode D6, which is converted into a third charging voltage by the second voltage regulator chip U5, and output from the negative electrode of the fifth diode D5 to the first energy storage circuit 20. The first energy storage circuit 20 is charged according to the third charging voltage.

[0105] The second energy storage circuit 600 continuously outputs the fourth input DC power to the input end of the third voltage stabilizing chip U6. The third voltage stabilizing chip U6 converts the fourth input DC power into a fourth charging voltage and outputs it from the cathode of the seventh diode D7 to the first energy storage circuit 20. The first energy storage circuit 20 is charged according to the fourth charging voltage.

[0106] When the microprocessor U1 detects that the battery voltage input to the third general input and output terminal P1.2 of the microprocessor U1 is less than the first preset voltage, the first enable signal is output from the first general input and output terminal P1.0 of the microprocessor U1 to the first end of the fifth resistor R5 and the first end of the sixth resistor R6, the second transistor U7 performs level conversion on the first enable signal based on the first enable signal, and outputs the first enable signal after level conversion from the collector C of the second transistor U7 to the first end of the second resistor R2, the user connects the USB voltage and / or the external voltage according to actual needs, the first voltage regulator chip U2 converts the USB voltage and / or the external voltage into the first charging voltage according to the first enable signal after level conversion, and the first energy storage circuit 20 is charged according to the first charging voltage.

[0107] When the microprocessor U1 detects that the battery voltage input to the third universal input and output terminal P1.2 of the microprocessor U1 is greater than the second preset voltage, a second enable signal is output from the second universal input and output terminal P1.1 of the microprocessor U1 to the second end of the third resistor R3 and the second end of the fourth resistor R4, and the first transistor U3 transmits the second input direct current to the positive electrode of the fourth diode D4 based on the second enable signal, and the battery charger U4 converts the second input direct current into a second charging voltage and outputs the second charging voltage from the charging output terminal of the battery charger U4, and the first energy storage circuit 20 is charged according to the second charging voltage.

[0108] An embodiment of the present application also provides an electronic device, which includes the above-mentioned charging circuit.

[0109] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0110] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A charging circuit connected to a first energy storage circuit for outputting a battery voltage, characterized in that: include: The control circuit is configured to output a first enable signal when the battery voltage is less than a first preset voltage, and output a second enable signal when the battery voltage is greater than or equal to a second preset voltage; a first conversion circuit, connected to the control circuit and the first energy storage circuit, configured to receive a first input direct current and convert the first input direct current into a first charging voltage based on the first enable signal; a power management circuit connected to the control circuit and the first energy storage circuit, configured to receive a second input direct current and convert the second input direct current into a second charging voltage based on the second enable signal; The first energy storage circuit is further configured to be charged according to the first charging voltage or the second charging voltage; The first preset voltage is smaller than the second preset voltage.

2. The charging circuit according to claim 1, characterized in that: The power management circuit comprises: a switch circuit, connected to the control circuit, configured to access the second input direct current and transmit the second input direct current based on the second enable signal; A charging management circuit is connected to the switch circuit and the first energy storage circuit, and is configured to convert the second input direct current into the second charging voltage.

3. The charging circuit according to claim 2, characterized in that: The switch circuit includes a first transistor, a third resistor and a fourth resistor; The emitter of the first transistor and the first end of the fourth resistor serve together as the second input DC power input end of the switch circuit to receive the second input DC power; the base of the first transistor is connected to the first end of the third resistor, and the second end of the third resistor and the second end of the fourth resistor serve together as the second enable signal input end of the switch circuit to be connected to the control circuit to input the second enable signal; The collector of the first transistor serves as the second input direct current output terminal of the switch circuit and is connected to the charging management circuit to output the second input direct current.

4. The charging circuit according to claim 2, characterized in that: The charging management circuit includes a battery charger, a fourth diode and a fifth resistor; The anode of the fourth diode serves as the second DC input terminal of the charging management circuit and is connected to the switch circuit to access the second DC input; the cathode of the fourth diode is connected to the charging power input terminal of the battery charger, the maximum charging current setting and the charging prohibition input terminal of the battery charger are connected to the first end of the fifth resistor, the ground terminal of the battery charger, the second end of the fifth resistor, the charging voltage setting of the battery charger and the intermediate voltage balance terminal of the massive capacitor are connected to the power ground; the charging output terminal of the battery charger serves as the second charging voltage output terminal of the charging management circuit and is connected to the first energy storage circuit to output the second charging voltage.

5. The charging circuit according to claim 1, characterized in that: Also includes: a photocell circuit configured to convert received light energy into a third input direct current; a second conversion circuit connected to the photocell circuit and the first energy storage circuit and configured to convert the third input direct current into a third charging voltage; The first energy storage circuit is further configured to be charged according to the third charging voltage.

6. The charging circuit according to claim 1, characterized in that: Also includes: a second energy storage circuit configured to output a fourth input direct current; a third conversion circuit, connected to the second energy storage circuit and the first energy storage circuit, configured to convert the fourth input direct current into a fourth charging voltage; The first energy storage circuit is further configured to be charged according to the fourth charging voltage.

7. The charging circuit according to claim 1, characterized in that: The first input direct current includes a USB voltage and an external voltage; The charging circuit further comprises: A USB interface configured to transfer the USB voltage; A first interface configured to transfer the external voltage; The first conversion circuit is specifically configured to access the USB voltage and / or the external voltage, and convert the USB voltage and / or the external voltage into a first charging voltage based on the first enable signal.

8. The charging circuit according to claim 1, characterized in that: Also includes: a level conversion circuit, connected to the control circuit and the first conversion circuit, and performing level conversion on the first enable signal; The first conversion circuit is specifically configured to access the first input direct current and convert the first input direct current into a first charging voltage based on the first enable signal after level conversion.

9. The charging circuit according to any one of claims 1 to 8, characterized in that: The control circuit includes a microprocessor; The first general input / output terminal of the microprocessor serves as the first enable signal output terminal of the control circuit and is connected to the first conversion circuit to output the first enable signal; The second general input and output terminal of the microprocessor serves as the second enable signal output terminal of the control circuit and is connected to the power management circuit to output the second enable signal; The third general input / output terminal of the microprocessor serves as a battery voltage input terminal of the third enable signal of the control circuit and is connected to the first energy storage circuit to input the battery voltage.

10. The charging circuit according to any one of claims 1 to 8, characterized in that: The first conversion circuit includes a first voltage stabilizing chip, a first diode, a second diode, a third diode, a first resistor and a second resistor; The anode of the first diode serves as the first first input DC power input terminal of the first conversion circuit to access the first first input DC power; the anode of the second diode serves as the second first input DC power input terminal of the first conversion circuit to access the second first input DC power; the cathode of the first diode, the cathode of the second diode, the first end of the first resistor and the input terminal of the first voltage stabilizing chip are connected, and the first end of the second resistor serves as the first enable signal input terminal of the first conversion circuit and is connected to the control circuit to input the first enable signal; the second end of the first resistor, the second end of the second resistor and the enable input terminal of the first voltage stabilizing chip are connected in common, the output terminal of the first voltage stabilizing chip is connected to the anode of the third diode, and the cathode of the third diode serves as the first charging voltage output terminal of the first conversion circuit and is connected to the first energy storage circuit to output the first charging voltage; the ground terminal of the first voltage stabilizing chip is connected to the power ground.

11. An electronic device, characterized in that: The electronic device comprises the charging circuit according to any one of claims 1 to 10.

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