Charging management circuit

Abstract

The utility model discloses a charging management circuit, and relates to the technical field of battery charging circuits. According to the utility model, the positive electrode of a direct-current voltage source DC is connected with the source electrode of an MOS tube Q3, and the drain electrode of the MOS tube Q3 is sequentially connected in series with an inductor LP, a diode D13 and a resistor R84 to the positive electrode of a battery charging end BAT; the chip U14 controls the on-off of the MOS tube Q3 through the switching tubes Q4, Q5 and Q6, thereby controlling the on-off of the charging circuit. According to the utility model, the charging circuit is used for charging the charging end of the battery, the control circuit is used for detecting the charging end of the battery, the on-off of the charging circuit and the charging voltage are controlled by controlling the on-off of the switching tubes Q6, Q4 and Q5 and the MOS tube Q3, and the chip U14 is used for controlling, so that the integration level is high, and the stability and the safety of the battery charging process are ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of battery charging circuits, and particularly relates to a charging management circuit. Background Technique

[0002] In people's daily life, various products that consume electric energy are often used, such as mobile communication tools, laptop computers, household appliances, power tools, or electric vehicles, etc. Some of these products that consume electric energy are equipped with rechargeable batteries. After the electric energy of the product is exhausted, a charger needs to be used to charge the battery of the product.

[0003] Taking an electric vehicle as an example, with the increasing popularity of electric vehicles, the corresponding chargers have higher and higher requirements for performance and cost. An excellent charger can extend the service life of the electric vehicle battery and achieve the purpose of energy conservation and environmental protection. However, the management circuits in existing electric vehicle chargers are all composed of multiple comparators and some discrete devices. There are many devices, the periphery is complex, and the functions are single. Due to the large number of devices, the circuit board area occupied by them is also relatively large, which is not conducive to reducing the cost of charger products. Summary of the Invention

[0004] The purpose of the utility model is to provide a charging management circuit, which controls the charging process of the battery charging end by setting a charging circuit, and detects whether the battery charging end is no-load through a control circuit, and controls the on-off of the charging circuit and the charging voltage by controlling the on-off of the switching transistors Q6, Q4, and Q5 and the MOS transistor Q3, and is controlled by the chip U14, with high integration, ensuring the stability and safety of the battery charging process, extending the service life of the battery, and providing a reliable charging effect.

[0005] To solve the above technical problems, the utility model is realized through the following technical solutions:

[0006] The utility model relates to a charging management circuit, which includes a charging circuit for charging a battery and a control circuit for controlling the on-off of the charging circuit; the control circuit includes a chip U14, a resistor R101 and a resistor R105; the charging circuit includes a DC voltage source DC, a MOS transistor Q3, switching transistors Q4, Q5 and Q6; the positive pole of the DC voltage source DC is connected to the source electrode of the MOS transistor Q3, and the drain electrode of the MOS transistor Q3 is successively connected in series with an inductor LP, a diode D13 and a resistor R84 to the positive pole of the battery charging terminal BAT; the gate electrode of the MOS transistor Q3 is successively connected in series with a resistor R82 and a capacitor C122 to the ground; the MOS transistor Q3 controls the on-off of the charging circuit; the emitter electrode of the switching transistor Q6 is grounded, and the collector electrode of the switching transistor Q6 is successively connected in series with resistors R83 and R85 to the DC voltage source DC; the base electrode of the switching transistor Q6 is connected in series with a resistor R81 to the 11th pin of the chip U14; the emitter electrodes of the switching transistors Q4 and Q5 are both connected to the intermediate connection point of the resistor R82 and the capacitor C122, the collector electrode of the switching transistor Q5 is grounded, and the collector electrode of the switching transistor Q4 is connected to a 20V voltage source; the base electrodes of the switching transistors Q4 and Q5 are both connected to the intermediate connection point of the resistors R83 and R85; the 19th pin of the chip U14 is successively connected in series with resistors R90 and R104 to the intermediate connection point between the resistor R84 and the battery charging terminal BAT; the 20th pin of the chip U14 is successively connected in series with resistors R94 and R103 to the intermediate connection point between the inductor LP and the diode D13; one end of the series circuit composed of the resistors R101 and R105 is connected to the intermediate connection point between the resistors R94 and R103, and the other end is connected to the intermediate connection point between the resistors R90 and R104; the intermediate connection point of the resistors R101 and R105 is grounded; the chip U14 controls the on-off of the MOS transistor Q3 through the switching transistors Q4, Q5 and Q6.

[0007] As a preferred technical solution of the utility model, the positive pole of the DC voltage source DC is further connected with grounding capacitors C107 and C108.

[0008] As a preferred technical solution of the utility model, the 6th pin of the chip U14 is successively connected in series with resistors R91 and R100 to a 20V voltage source; the intermediate connection point of the resistors R91 and R100 is further connected with a grounding capacitor C124 and a grounding resistor R102; the 7th pin of the chip U14 is grounded, and the 5th pin of the chip U14 is successively connected in series with a resistor R00 and a diode D9 to a voltage source VDD.

[0009] As a preferred technical solution of the utility model, the 14th pin of the chip U14 is successively connected in series with a resistor R93 and a light-emitting diode LED2 to the ground, and the chip U14 controls the lighting and extinguishing of the light-emitting diode LED2 to display the charging state.

[0010] As a preferred technical solution of the present utility model, a resistor R79 is connected in series between the base and the emitter of the switching transistor Q6, and both ends of the resistor R79 are connected in parallel with a capacitor C113.

[0011] As a preferred technical solution of the present utility model, both ends of the resistor R101 are connected in parallel with a capacitor C123, and both ends of the resistor R105 are connected in parallel with a capacitor C125.

[0012] The present utility model has the following beneficial effects:

[0013] The present utility model controls the charging process of the battery charging terminal by setting a charging circuit, detects whether the battery charging terminal is no-load through a control circuit, and controls the on-off of the charging circuit and the charging voltage by controlling the on-off of the switching transistors Q6, Q4 and Q5 and the MOS transistor Q3. It is controlled by the single-chip microcomputer chip U14, with high integration, ensuring the stability and safety of the battery charging process, prolonging the service life of the battery, and providing a reliable charging effect.

[0014] Of course, it is not necessary for any product implementing the present utility model to achieve all the above-mentioned advantages simultaneously. Description of the Drawings

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

[0016] Figure 1 It is a circuit diagram of the charging circuit of a charging management circuit;

[0017] Figure 2 It is a circuit diagram of the control circuit. Detailed Embodiments

[0018] The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only some of the embodiments of the present utility model, rather than all of them. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments of the present utility model belong to the protection scope of the present utility model.

[0019] Please refer to Figure 1-2As shown in the figure, the utility model relates to a charging management circuit, which includes a charging circuit for charging a battery and a control circuit for controlling the on / off of the charging circuit; the control circuit includes a chip U14, a resistor R101 and a resistor R105; the charging circuit includes a DC voltage source DC, a MOS transistor Q3, switching transistors Q4, Q5 and Q6; the chip U14 controls the on / off of the MOS transistor Q3 through the switching transistors Q4, Q5 and Q6, so as to realize the on / off of the charging circuit and the control of the charging voltage.

[0020] The positive pole of the DC voltage source DC is connected to the source electrode of the MOS transistor Q3, and the positive pole of the DC voltage source DC is also connected with grounding capacitors C107 and C108; the drain electrode of the MOS transistor Q3 is sequentially connected in series with an inductor LP, a diode D13 and a resistor R84 to the positive pole of the battery charging terminal BAT; the gate electrode of the MOS transistor Q3 is sequentially connected in series with a resistor R82 and a capacitor C122 to the ground; the MOS transistor Q3 controls the on / off of the charging circuit.

[0021] The emitter of the switching transistor Q6 is grounded, the collector of the switching transistor Q6 is sequentially connected in series with resistors R83 and R85 to the DC voltage source DC; the base of the switching transistor Q6 is connected in series with a resistor R81 to the 11th pin of the chip U14; a resistor R79 is connected in series between the base and the emitter of the switching transistor Q6, and both ends of the resistor R79 are connected in parallel with a capacitor C113.

[0022] The emitters of the switching transistors Q4 and Q5 are both connected to the intermediate connection point of the resistor R82 and the capacitor C122, the collector of the switching transistor Q5 is grounded, and the collector of the switching transistor Q4 is connected to a 20V voltage source; the bases of the switching transistors Q4 and Q5 are both connected to the intermediate connection point of the resistors R83 and R85.

[0023] The 19th pin of the chip U14 is sequentially connected in series with resistors R90 and R104 to the intermediate connection point between the resistor R84 and the battery charging terminal BAT; the 20th pin of the chip U14 is sequentially connected in series with resistors R94 and R103 to the intermediate connection point between the inductor LP and the diode D13; one end of the series circuit composed of the resistors R101 and R105 is connected to the intermediate connection point between the resistors R94 and R103, and the other end is connected to the intermediate connection point between the resistors R90 and R104; the intermediate connection point of the resistors R101 and R105 is grounded; both ends of the resistor R101 are connected in parallel with a capacitor C123, and both ends of the resistor R105 are connected in parallel with a capacitor C125.

[0024] Pin 6 of chip U14 is serially connected to a 20V voltage source through resistors R91 and R100 in sequence; a ground capacitor C124 and a ground resistor R102 are also connected to the midpoint between resistors R91 and R100; pin 7 of chip U14 is grounded, and pin 5 of chip U14 is serially connected to voltage source VDD through resistors R00 and diode D9 in sequence; pin 14 of chip U14 is serially connected to a light-emitting diode LED2 through resistor R93 to ground, and chip U14 controls the lighting and extinguishing of the light-emitting diode LED2 to display the charging status.

[0025] This embodiment is about the working principle of a charging management circuit, and the working process is as follows:

[0026] When the battery at the BAT terminal is unloaded, pins P19 / P20 of chip U14 are at high level, and pin P10 outputs low level. At this time, switch Q6 is cut off, pin 4 of MOS transistor Q3 is at high level, and MOS transistor Q3 conducts normally, and the BAT battery terminal obtains the same voltage as the input terminal. When a battery is plugged in at the BAT terminal for charging, the voltage obtained by pins P19 / P20 of chip U14 through the voltage-dividing resistors gradually increases from low. The voltage of pin P10 of chip U14 also gradually increases. After the base voltage of switch Q6 gradually increases and conducts, the collector voltage decreases, resulting in the emitter voltages of switch Q4 and switch Q5 decreasing, the voltage of pin 4 of MOS transistor Q3 decreasing, and MOS transistor Q3 outputting a corresponding voltage to charge the battery. As the charging voltage and current gradually increase, the voltage obtained by pins P19 / P20 of chip U14 through the voltage-dividing resistors continues to increase from low, the collector voltage of switch Q6 continues to decrease, the voltage of pin 4 of MOS transistor Q3 continues to decrease, and the output voltage increases and the current gradually increases to continuously charge the battery. When the voltage difference detected by pins P19 / P20 of chip U14 across resistor R84 decreases to a certain value, the voltage of pin P10 of chip U14 controls MOS transistor Q3 to turn off through Q4, Q5, and Q6, and the charging is completed.

[0027] In the description of this specification, the descriptions referring to terms such as "one embodiment", "example", "specific example", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0028] The preferred embodiments of the present utility model disclosed above are only used to help illustrate the present utility model. The preferred embodiments do not describe all the details in detail, nor do they limit the present utility model to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principle and practical application of the present utility model, so that those skilled in the relevant technical field can well understand and utilize the present utility model. The present utility model is only limited by the claims and their full scope and equivalents.

Claims

1. A charging management circuit, characterized in that: It includes a charging circuit for charging the battery, and a control circuit for controlling the on and off of the charging circuit; the control circuit includes a chip U14, a resistor R101 and a resistor R105; The charging circuit includes a direct current voltage source DC, a MOS tube Q3, switch tubes Q4, Q5 and Q6; The positive electrode of the DC voltage source DC is connected to the source electrode of the MOS transistor Q3; the drain electrode of the MOS transistor Q3 is connected in series with the inductor LP, the diode D13 and the resistor R84 to the positive electrode of the battery charging terminal BAT; the gate electrode of the MOS transistor Q3 is connected in series with the resistor R82 and the capacitor C122 to the ground; the MOS transistor Q3 controls the on and off of the charging circuit; The emitter of the switch tube Q6 is grounded, and the collector of the switch tube Q6 is connected in series with resistors R83 and R85 to a DC voltage source DC; the base of the switch tube Q6 is connected in series with resistor R81 to pin 11 of the chip U14; The emitters of the switch tubes Q4 and Q5 are connected to the middle connection point of the resistor R82 and the capacitor C122, the collector of the switch tube Q5 is grounded, and the collector of the switch tube Q4 is connected to a 20V voltage source; the bases of the switch tubes Q4 and Q5 are connected to the middle connection point of the resistors R83 and R85; Pin 19 of the chip U14 is connected in series with resistors R90 and R104 to the middle connection point between the resistor R84 and the battery charging terminal BAT; Pin 20 of the chip U14 is connected in series with resistors R94 and R103 to the middle connection point between the inductor LP and the diode D13; One end of the series circuit composed of the resistors R101 and R105 is connected to the middle connection point of the resistors R94 and R103, and the other end is connected to the middle connection point of the resistors R90 and R104; the middle connection point of the resistors R101 and R105 is grounded; The chip U14 controls the on and off of the MOS tube Q3 through the switch tubes Q4, Q5 and Q6.

2. A charging management circuit according to claim 1, characterized in that: The positive electrode of the DC voltage source DC is also connected to grounding capacitors C107 and C108.

3. A charging management circuit according to claim 1, characterized in that: Pin 6 of the chip U14 is connected in series with resistors R91 and R100 to a 20V voltage source; the middle connection point between the resistors R91 and R100 is also connected to a grounding capacitor C124 and a grounding resistor R102; Pin 7 of the chip U14 is grounded, and pin 5 of the chip U14 is connected in series with a resistor R00 and a diode D9 to a voltage source VDD.

4. A charging management circuit according to claim 1, characterized in that: Pin 14 of the chip U14 is connected in series with a resistor R93 and a light emitting diode LED2 to ground, and the chip U14 controls the light emitting diode LED2 to indicate the charging status.

5. A charging management circuit according to claim 1, characterized in that: A resistor R79 is connected in series between the base and the emitter of the switch tube Q6 , and both ends of the resistor R79 are connected in parallel with the capacitor C113 .

6. A charging management circuit according to claim 1, characterized in that: Both ends of the resistor R101 are connected in parallel with the capacitor C123 , and both ends of the resistor R105 are connected in parallel with the capacitor C125 .

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