Battery charging circuit

Abstract

The utility model discloses a battery charging circuit, and relates to the technical field of battery charging, the battery charging circuit comprises a charging switch, the input end of the charging switch is connected with the positive electrode of a power supply, the output end of the charging switch is connected with the positive electrode of a battery, and the negative electrode of the battery is grounded; the input end of the feedback switch is connected with the positive electrode of the battery, and the control end of the feedback switch receives the opening signal; a charging detection pin of the single-chip microcomputer is connected with the output end of the feedback switch and the control end of the charging switch; when the charging detection pin of the single-chip microcomputer outputs a high level signal, the charging switch charges the battery. When the charging detection pin of the single-chip microcomputer outputs a low-level signal, the single-chip microcomputer detects the electric quantity of the battery through the feedback switch. The circuit is simple in structure and low in cost, only one pin of the single-chip microcomputer is used for control and detection, battery charging can be controlled, the electric quantity of the battery can also be detected, the overall production cost of the circuit is saved, and the occupied space of the circuit is also saved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery charging, in particular to a battery charging circuit. Background Art

[0002] In a traditional battery charging circuit, the charging circuit of the battery and the power detection circuit of the battery are two separately designed circuits. The main control chip uses one pin to control the charging circuit to charge the battery, and uses another pin to control the power detection circuit to detect the power of the battery. The two pins are paired with two external circuits, one is the charging circuit for charging the battery, and the other is the power detection circuit for detecting the power of the battery, which makes the overall production cost of the circuit high and the occupied space of the circuit large. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a battery charging circuit. This application only needs a feedback switch, a charging switch and a control module, and only one pin of the control module is used for control and detection, that is, it can control the battery charging and detect the power of the battery, saving the overall production cost of the circuit and also saving the occupied space of the circuit.

[0004] To solve the above technical problems, the utility model adopts the following technical solutions:

[0005] One aspect of an embodiment of the utility model provides a battery charging circuit, which includes: a charging switch, the input end of the charging switch is connected to the positive pole of the power supply, the output end of the charging switch is connected to the positive pole of the battery, and the negative pole of the battery is grounded; a feedback switch, the input end of the feedback switch is connected to the positive pole of the battery, and the control end of the feedback switch receives an enabling signal; a control module, the charging detection pin of the control module is connected to the output end of the feedback switch and the control end of the charging switch; when the charging detection pin of the control module outputs a high-level signal, the charging switch charges the battery; when the charging detection pin of the control module outputs a low-level signal, the control module detects the power of the battery through the feedback switch.

[0006] In some embodiments, the charging switch includes a first NPN transistor, the collector of the first NPN transistor is connected to the positive pole of the power supply, the base of the first NPN transistor is connected to the charging detection pin of the control module, and the emitter of the first NPN transistor is connected to the positive pole of the battery.

[0007] In some embodiments, the charging switch further includes a first resistor and a second resistor, one end of the first resistor is connected to the base of the first NPN transistor, the other end of the first resistor is connected to the charging detection pin of the control module, and the collector of the first NPN transistor is connected to the positive pole of the power supply through the second resistor.

[0008] In some embodiments, the charging switch further includes a third resistor, one end of the third resistor is connected to the other end of the first resistor, and the other end of the third resistor is grounded.

[0009] In some embodiments, the feedback switch includes a second NPN transistor, the collector of the second NPN transistor is connected to the positive electrode of the battery, the base of the second NPN transistor receives an enabling signal, and the emitter of the second NPN transistor is connected to the charging detection pin of the control module.

[0010] In some embodiments, the feedback switch further includes a fourth resistor and a fifth resistor, the base of the second NPN transistor is connected to the positive electrode of the power supply through the fourth resistor, the collector of the second NPN transistor is connected to the positive electrode of the battery through the fifth resistor, and the emitter of the second NPN transistor is connected to the charging detection pin of the control module.

[0011] In some embodiments, the battery charging circuit further includes a fuse, one end of the fuse is connected to the output end of the charging switch and the input end of the feedback switch, and the other end of the fuse is connected to the positive electrode of the battery.

[0012] In some embodiments, the battery charging circuit further includes an interface, a first electrode of the interface is connected to the other end of the fuse, and a second electrode of the interface is grounded.

[0013] According to an embodiment of the present invention, a battery charging circuit has at least the following beneficial effects: the charging detection pin of the control module is connected to the output end of the feedback switch and the control end of the charging switch. When the charging detection pin of the control module outputs a high-level signal, the charging switch charges the battery; when the charging detection pin of the control module outputs a low-level signal, the control module detects the battery power through the feedback switch. This application only needs a feedback switch, a charging switch and a control module to realize the functions of both controlling battery charging and detecting battery power, saving the overall production cost of the circuit and also saving the occupied space of the circuit.

[0014] It should be understood that the above general description and the following detailed description are only exemplary and do not limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0016] Figure 1 This is the schematic diagram of the battery charging circuit for some embodiments of the present application.

[0017] The description of the reference numerals in the drawings is as follows: 1. Charging switch; 2. Feedback switch. Detailed implementation manners

[0018] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0019] The terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", and "third" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise stated, the meaning of "a plurality" is two or more.

[0020] In the description of the present utility model, it should be noted that unless otherwise clearly defined and limited, the terms "connected" and "connected to" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0021] Now, the exemplary embodiments will be described more comprehensively with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; on the contrary, these exemplary embodiments are provided so that the present disclosure will be more thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus their repeated description will be omitted.

[0022] The technical solutions of the embodiments of the present application will be briefly described below:

[0023] According to some embodiments, the present application provides a battery charging circuit. The battery charging circuit includes a charging switch 1, a feedback switch 2, and a control module, and their connection structure is as follows:

[0024] The input terminal of the charging switch 1 is connected to the positive pole of the power supply VCC, the output terminal of the charging switch 1 is connected to the positive pole of the battery, and the negative pole of the battery is grounded;

[0025] The input terminal of the feedback switch 2 is connected to the positive pole of the battery, and the control terminal of the feedback switch 2 receives the enabling signal;

[0026] The charging detection pin CD of the control module is connected to the output terminal of the feedback switch 2 and the control terminal of the charging switch 1.

[0027] Based on the working principle of the above embodiment, the control module is configured such that when the battery is charging, the charging detection pin CD of the control module outputs a continuous square wave signal, that is, a continuous high and low level signal; when the battery supplies power to the load, the charging detection pin CD of the control module outputs a continuous low level signal.

[0028] Among them, the control terminal of the feedback switch 2 always receives the enabling signal and is always in the open state, but the opening degree is not large, and the potential of the output electrical signal is not high. The charging switch 1 is configured to be turned on when receiving a high level.

[0029] When the charging detection pin CD of the control module outputs a high level signal, the control terminal of the charging switch 1 receives the high level signal, and the charging switch 1 is turned on to output the power supply VCC to the battery for charging. Among them, the feedback switch 2 is always in the open state, but the potential of the high level signal output by the charging detection pin CD of the control module is higher than the potential of the electrical signal output by the feedback switch 2, so the electrical signal output by the feedback switch 2 cannot be input into the control module.

[0030] When the charging detection pin CD of the control module outputs a low level signal, the charging detection pin CD of the control module receives the electrical signal output by the feedback switch 2, and the control module determines the battery power according to the value of the electrical signal. Among them, the control module uses a single-chip microcomputer.

[0031] The following combines the appendix of this specification Figure 1 , and further elaborates on the preferred embodiments of the present disclosure in detail.

[0032] According to some embodiments, as Figure 1 shown, the charging switch 1 includes a first NPN transistor Q1. The collector of the first NPN transistor Q1 is connected to the positive pole of the power supply VCC, the base of the first NPN transistor Q1 is connected to the charging detection pin CD of the control module, and the emitter of the first NPN transistor Q1 is connected to the positive pole of the battery.

[0033] The working principle of the above embodiment is as follows: when the charging detection pin CD of the control module outputs a high-level signal, the base of the first NPN transistor Q1 receives the high-level signal, the first NPN transistor Q1 conducts, and the first NPN transistor Q1 charges the battery. When the charging detection pin CD of the control module outputs a low-level signal, the electrical signal output by the feedback switch 2 is input to the charging detection pin CD of the control module, the base of the first NPN transistor Q1 does not receive the high-level signal, the first NPN transistor Q1 is cut off, and the battery does not charge.

[0034] Further, according to some embodiments, such as Figure 1 shown, the charging switch 1 further includes a first resistor R1 and a second resistor R2. One end of the first resistor R1 is connected to the base of the first NPN transistor Q1, the other end of the first resistor R1 is connected to the charging detection pin CD of the control module, and the collector of the first NPN transistor Q1 is connected to the positive electrode of the power supply VCC through the second resistor R2.

[0035] Further, according to some embodiments, the charging switch 1 further includes a third resistor R3. One end of the third resistor R3 is connected to the other end of the first resistor R1, and the other end of the third resistor R3 is grounded.

[0036] Further, according to some embodiments, such as Figure 1 shown, the feedback switch 2 includes a second NPN transistor Q2. The collector of the second NPN transistor Q2 is connected to the positive electrode of the battery, the base of the second NPN transistor Q2 receives the enabling signal, and the emitter of the second NPN transistor Q2 is connected to the charging detection pin CD of the control module.

[0037] Further, according to some embodiments, the feedback switch 2 further includes a fourth resistor R4 and a fifth resistor R5. The base of the second NPN transistor Q2 is connected to the positive electrode of the power supply VCC through the fourth resistor R4, the collector of the second NPN transistor Q2 is connected to the positive electrode of the battery through the fifth resistor R5, and the emitter of the second NPN transistor Q2 is connected to the charging detection pin CD of the control module.

[0038] Among them, the third resistor R3 and the fifth resistor R5 are used for voltage division.

[0039] Based on the working principle of the above embodiments, the base of the second NPN transistor Q2 has been receiving the high-level signal from the positive electrode of the power supply VCC through the fourth resistor R4. Therefore, the second NPN transistor Q2 is always in the conducting state. However, the resistance value of the fourth resistor R4 is relatively high, causing the second NPN transistor Q2 not to reach the saturation state and be between the cut-off and amplification regions. So when the charging detection pin CD of the control module outputs a high-level signal, the potential of the high-level signal output by the charging detection pin CD of the control module is higher than the potential of the electrical signal output by the emitter of the second NPN transistor Q2. Therefore, the electrical signal output by the emitter of the second NPN transistor Q2 cannot be input into the control module.

[0040] According to some embodiments, the battery charging circuit further includes a fuse F. One end of the fuse F is connected to the output end of the charging switch 1 and the input end of the feedback switch 2, and the other end of the fuse F is connected to the positive electrode of the battery. The fuse F is used to melt itself and cut off the current when the current abnormally rises to a certain height to protect the safe operation of the circuit.

[0041] According to some embodiments, the battery charging circuit further includes an interface CON. The first electrode of the interface CON is connected to the other end of the fuse F, and the second electrode of the interface CON is grounded. The interface CON in the circuit is used to plug into the interface of the battery to facilitate the connection and disassembly of the battery.

[0042] In some embodiments, the control module uses a single-chip microcomputer.

[0043] As Figure 1 shown, the overall working principle of this application is as follows: When the charging detection pin CD of the single-chip microcomputer outputs a high-level signal, the base of the first NPN transistor Q1 receives the high-level signal, and the first NPN transistor Q1 conducts, outputting the power supply VCC to charge the battery. Among them, the second NPN transistor Q2 is always in the conducting state, but the potential of the high-level signal output by the charging detection pin CD of the single-chip microcomputer is higher than the potential of the electrical signal output by the second NPN transistor Q2. Therefore, the electrical signal output by the second NPN transistor Q2 cannot be input into the control module.

[0044] When the charging detection pin CD of the single-chip microcomputer outputs a low-level signal, the charging detection pin CD of the single-chip microcomputer receives the electrical signal output by the second NPN transistor Q2, and the single-chip microcomputer determines the battery power according to the value of the electrical signal.

[0045] In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples.

[0046] While the present disclosure has been described with reference to several exemplary embodiments, it should be understood that the terms used are descriptive and exemplary rather than restrictive. Since the present disclosure can be embodied in many forms without departing from the spirit or essence of the present application, it should be understood that the above-described embodiments are not limited to any of the foregoing details, but rather should be broadly construed within the spirit and scope defined by the appended claims, and thus all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A battery charging circuit, characterized in that: The battery charging circuit comprises: A charging switch, wherein an input end of the charging switch is connected to a positive electrode of a power source, an output end of the charging switch is connected to a positive electrode of a battery, and a negative electrode of the battery is grounded; A feedback switch, wherein an input end of the feedback switch is connected to the positive electrode of the battery, and a control end of the feedback switch receives a start signal; A control module, wherein a charging detection pin of the control module is connected to an output end of the feedback switch and a control end of the charging switch; The charging switch comprises a first NPN transistor, the collector of the first NPN transistor is connected to the positive electrode of the power supply, the base of the first NPN transistor is connected to the charging detection pin of the control module, and the emitter of the first NPN transistor is connected to the positive electrode of the battery; The feedback switch comprises a second NPN transistor, the collector of the second NPN transistor is connected to the positive electrode of the battery, the base of the second NPN transistor receives a start signal, and the emitter of the second NPN transistor is connected to the charging detection pin of the control module; When the charging detection pin of the control module outputs a high level signal, the first NPN transistor charges the battery; When the charging detection pin of the control module outputs a low level signal, the control module detects the power level of the battery through the second NPN transistor.

2. The battery charging circuit according to claim 1, characterized in that: The charging switch also includes a first resistor and a second resistor, the base of the first NPN transistor is connected to one end of the first resistor, the other end of the first resistor is connected to the charging detection pin of the control module, and the collector of the first NPN transistor is connected to the positive electrode of the power supply through the second resistor.

3. The battery charging circuit according to claim 2, characterized in that: The charging switch further includes a third resistor, one end of the third resistor is connected to the other end of the first resistor, and the other end of the third resistor is grounded.

4. The battery charging circuit according to claim 1, characterized in that: The feedback switch further includes a fourth resistor and a fifth resistor, the base of the second NPN transistor is connected to the positive electrode of the power supply through the fourth resistor, and the collector of the second NPN transistor is connected to the positive electrode of the battery through the fifth resistor.

5. The battery charging circuit according to claim 1, characterized in that: The battery charging circuit further comprises a fuse, one end of which is connected to the output end of the charging switch and the input end of the feedback switch, and the other end of the fuse is connected to the positive electrode of the battery.

6. The battery charging circuit according to claim 5, characterized in that: The battery charging circuit further comprises an interface, a first electrode of the interface is connected to the other end of the fuse, and a second electrode of the interface is grounded.

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