A charger

Abstract

This utility model discloses a charger, relating to the field of charger technology, comprising: a charging module, including a constant current charging module for outputting a constant current to the battery and a constant voltage charging module for outputting a constant voltage to the battery; a power supply module for supplying power to the constant current charging module and the constant voltage charging module; and a switching module for controlling the constant current charging module to charge the battery until the battery voltage reaches a threshold, and controlling the constant voltage charging module to charge the battery after the battery voltage reaches the threshold. This utility model controls the constant current charging module to charge the battery until the battery voltage reaches the threshold, and then controls the constant voltage charging module to charge the battery after the battery voltage reaches the threshold, effectively avoiding the aggravated battery polarization caused by continuous constant current in the later stages of charging, and also avoiding damage to the battery caused by excessive current due to excessively high initial charging voltage.

Description

Technical Field

[0001] This utility model relates to the field of charger technology, and in particular to a charger. Background Technology

[0002] Currently, battery chargers on the market can only charge batteries of the same type. The chargers have poor versatility and cannot charge different types of batteries according to their specific charging characteristics. This results in poor charger versatility and an inability to meet the charging needs of different types of batteries. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a charger.

[0004] To solve the above technical problems, the technical solution of this utility model is as follows:

[0005] A charger, comprising:

[0006] The charging module includes a constant current charging module for outputting a constant current to the battery and a constant voltage charging module for outputting a constant voltage to the battery.

[0007] A power supply module is used to power the constant current charging module and the constant voltage charging module;

[0008] In addition, a switching module is used to control the constant current charging module to charge the battery until the battery voltage reaches a threshold, and to control the constant voltage charging module to charge the battery after the battery voltage reaches the threshold.

[0009] As a preferred embodiment of the charger described in this utility model, the constant current charging module includes a constant current circuit, which includes a transistor Q1, a second resistor R2, a third resistor R3, and a fourth resistor R4.

[0010] The base of transistor Q1 is connected in series with the third resistor R3 and then connected to the positive output terminal of the power supply module. The collector of transistor Q1 is connected in series with diode D4 and the fourth resistor R4 to serve as the positive output terminal. The emitter of transistor Q1 is connected in series with the second resistor R2 and then grounded to serve as the negative output terminal.

[0011] In a preferred embodiment of the charger described in this utility model, the constant current charging module further includes a voltage regulator circuit, which includes a first voltage regulator diode, a second voltage regulator diode, and a third voltage regulator diode. The first voltage regulator diode, the second voltage regulator diode, and the third voltage regulator diode are connected in parallel and then connected in series with the constant current circuit.

[0012] In a preferred embodiment of the charger described in this utility model, the constant current charging module includes a state feedback circuit, which includes a first light-emitting diode, a second light-emitting diode, and a first resistor R1. The first light-emitting diode and the first resistor R1 are connected in series and then in parallel at the front end of the constant current circuit, and the second light-emitting diode and the second resistor R2 are connected in parallel.

[0013] As a preferred embodiment of the charger described in this utility model, the constant voltage charging module includes an overvoltage protection circuit, the overvoltage protection circuit includes two sets of overvoltage protection units, and each set of overvoltage protection units includes a Zener diode, a thyristor, a first resistor and a second resistor.

[0014] One end of the Zener diode is connected to the positive terminal of the main circuit, and the other end of the Zener diode is grounded. One end of the thyristor is connected to the positive terminal of the main circuit, and the other end of the thyristor is grounded. The first resistor is connected in series between the thyristor and the Zener diode, and the second resistor is connected between the Zener diode and the ground terminal.

[0015] In a preferred embodiment of the charger described in this utility model, the power supply module includes a transformer step-down circuit, a rectifier filter circuit, and a voltage regulator circuit.

[0016] The beneficial effects of this utility model are:

[0017] (1) The present invention controls the constant current charging module to charge the battery until the battery voltage reaches the threshold, and controls the constant voltage charging module to charge the battery after the battery voltage reaches the threshold. This effectively avoids the battery polarization caused by continuous constant current in the later stage of charging, and also avoids the battery being damaged by excessive current due to excessive charging voltage in the early stage.

[0018] (2) The constant current charging module provided by this utility model includes a voltage regulator circuit. When working normally, the voltage regulator is in a high configuration and does not affect the normal operation of the circuit. When the circuit experiences instantaneous high voltage, the voltage regulator breaks down and conducts, clamping the voltage to about 15V to prevent the downstream components from being damaged due to overvoltage.

[0019] (3) The constant voltage charging module provided by this utility model includes an overvoltage protection circuit. The thyristor Q40 is normally in the off state. When the input voltage rises abnormally, the Zener diode breaks down in reverse and conducts. The first resistor has current, which triggers the gate of the thyristor and turns it on. Once the thyristor is turned on, it will "pull down" the input voltage and short-circuit (approximately directly conduct to ground). The fuse blows due to excessive current, completely cutting off the input and realizing overvoltage protection. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A circuit diagram of the constant current charging module in the charger provided by this utility model;

[0022] Figure 2 This is a circuit diagram of the overvoltage protection circuit in the constant voltage charging module of the charger. Detailed Implementation

[0023] To make the contents of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0024] This application provides a charger, which includes a charging module, a power supply module, and a switching module. The power supply module supplies power to the charging module. The charging module includes a constant current charging module and a constant voltage charging module. The switching module controls the constant current charging module to charge the battery until the battery voltage reaches a threshold, and then controls the constant voltage charging module to charge the battery after the battery voltage reaches the threshold.

[0025] Specifically, the constant current charging module is used to charge the battery by outputting a constant current. See also Figure 1 The constant current charging module includes a constant current circuit. This constant current circuit includes a transistor Q1, a second resistor R2, a third resistor R3, and a fourth resistor R4. The base of transistor Q1 is connected in series with the third resistor R3 and then connected to the positive output terminal of the power supply module. The collector of transistor Q1 is connected in series with diode D4 and the fourth resistor R4 to form the positive output terminal. The emitter of transistor Q1 is connected in series with the second resistor R2 and then grounded to form the negative output terminal.

[0026] In the constant current circuit described above, diode D4 is used for reverse voltage protection. If a reverse voltage occurs at the load terminal, diode D4 conducts to clamp the transistor Q1, preventing it from being reverse-biased and broken down. The fourth resistor is used for current sampling, converting the current signal into a voltage signal, which is then fed back to the control circuit. The third resistor R3 limits the base current of the transistor, protecting Q1. The second resistor, in conjunction with the base circuit, stabilizes the operating point of transistor Q1.

[0027] See Figure 1The constant current charging module also includes a voltage regulator circuit. This voltage regulator circuit includes a first Zener diode, a second Zener diode, and a third Zener diode. The first, second, and third Zener diodes are connected in parallel and then in series with the constant current circuit. Under normal operation, the Zener diodes are in a high-voltage configuration, which does not affect the normal operation of the circuit. When a momentary high voltage occurs in the circuit, the Zener diodes break down and conduct, clamping the voltage to around 15V to prevent damage to downstream components due to overvoltage.

[0028] In addition, the aforementioned constant current circuit also includes a status feedback circuit. This status feedback circuit includes a first LED, a second LED, and a first resistor R1. The first LED and the first resistor R1 are connected in series and then in parallel at the front end of the constant current circuit to indicate power supply; that is, when the circuit is powered on, the first LED is turned on, and the green light illuminates, indicating that the power supply is normal. The second LED and the second resistor R2 are connected in parallel to indicate the operating status. When transistor Q1 is turned on, the second LED is turned on, and the red light illuminates, indicating that the feedback circuit is in operating mode.

[0029] The constant voltage charging module includes an overvoltage protection circuit. See also... Figure 2 The overvoltage protection circuit includes two sets of overvoltage protection units. Each set of overvoltage protection units includes a Zener diode, a thyristor, a first resistor, and a second resistor. One end of the Zener diode is connected to the positive terminal of the main circuit, and the other end is grounded. One end of the thyristor is connected to the positive terminal of the main circuit, and the other end is grounded. The first resistor is connected in series between the thyristor and the Zener diode, and the second resistor is connected between the Zener diode and the ground terminal.

[0030] Taking an overvoltage protection unit as an example, the Zener diode D15 is in reverse cutoff mode when the input voltage is normally 5.5V, which does not affect the circuit operation. The thyristor Q40 is normally off. When the input voltage abnormally increases (exceeding the Zener diode D15's 6.2V regulation voltage), the Zener diode D15 breaks down in reverse and conducts. Current flows through the first resistor R91, triggering the gate of the thyristor Q40, causing it to conduct. Once the thyristor Q40 conducts, it "pulls down" the input voltage, short-circuiting it (approximately directly connecting it to ground). The fuse F1 blows due to excessive current, completely cutting off the input and achieving overvoltage protection.

[0031] The power supply module includes a transformer step-down circuit, a rectifier and filter circuit, and a voltage regulator circuit. The transformer step-down circuit reduces the 220V AC voltage to a lower AC voltage, such as 9V. Then, the rectifier and filter circuit rectifies the 9V AC power, converting it into pulsating DC power. After rectification, the filter smooths the output, resulting in a relatively stable DC power. Finally, the voltage regulator circuit stabilizes the input DC voltage at 5.5V.

[0032] The switching module is existing technology and will not be described in detail in this embodiment.

[0033] Therefore, the technical solution of this application controls the constant current charging module to charge the battery until the battery voltage reaches the threshold, and controls the constant voltage charging module to charge the battery after the battery voltage reaches the threshold. This effectively avoids the battery polarization caused by continuous constant current in the later stage of charging, and also avoids the battery being damaged by excessive current due to excessive charging voltage in the early stage.

[0034] In addition to the above embodiments, this utility model may have other implementation methods; all technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope claimed by this utility model.

Claims

1. A charger characterized by: include: The charging module includes a constant current charging module for outputting a constant current to the battery and a constant voltage charging module for outputting a constant voltage to the battery. A power supply module is used to power the constant current charging module and the constant voltage charging module; In addition, a switching module is used to control the constant current charging module to charge the battery until the battery voltage reaches a threshold, and to control the constant voltage charging module to charge the battery after the battery voltage reaches the threshold.

2. The charger of claim 1, wherein: The constant current charging module includes a constant current circuit, which includes a transistor Q1, a second resistor R2, a third resistor R3, and a fourth resistor R4. The base of transistor Q1 is connected in series with the third resistor R3 and then connected to the positive output terminal of the power supply module. The collector of transistor Q1 is connected in series with diode D4 and the fourth resistor R4 to serve as the positive output terminal. The emitter of transistor Q1 is connected in series with the second resistor R2 and then grounded to serve as the negative output terminal.

3. The charger of claim 2, wherein: The constant current charging module further includes a voltage regulator circuit, which includes a first voltage regulator diode, a second voltage regulator diode, and a third voltage regulator diode. The first voltage regulator diode, the second voltage regulator diode, and the third voltage regulator diode are connected in parallel and then connected in series with the constant current circuit.

4. The charger of claim 3, wherein: The constant current charging module includes a status feedback circuit, which includes a first light-emitting diode, a second light-emitting diode, and a first resistor R1. The first light-emitting diode and the first resistor R1 are connected in series and then in parallel at the front end of the constant current circuit, and the second light-emitting diode and the second resistor R2 are connected in parallel.

5. The charger of claim 1, wherein: The constant voltage charging module includes an overvoltage protection circuit, which includes two sets of overvoltage protection units. Each set of overvoltage protection units includes a Zener diode, a thyristor, a first resistor, and a second resistor. One end of the Zener diode is connected to the positive terminal of the main circuit, and the other end of the Zener diode is grounded. One end of the thyristor is connected to the positive terminal of the main circuit, and the other end of the thyristor is grounded. The first resistor is connected in series between the thyristor and the Zener diode, and the second resistor is connected between the Zener diode and the ground terminal.

6. The charger of claim 1, wherein: The power supply module includes a transformer step-down circuit, a rectifier filter circuit, and a voltage regulator circuit.

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