CN220857623U

CN220857623U - Current protection circuit is prevented flowing backward by battery package for charging ware

Info

Publication number: CN220857623U
Application number: CN202321502333.5U
Authority: CN
Inventors: 闵羽飞
Original assignee: Jiangsu Yihe Electronic Co ltd
Current assignee: Jiangsu Yihe Electronic Co ltd
Priority date: 2023-06-13
Filing date: 2023-06-13
Publication date: 2024-04-26
Anticipated expiration: 2033-06-13

Abstract

The utility model provides a battery pack anti-backflow current protection circuit for a charger, which comprises a reference voltage module, a comparator U1 and a comparator, wherein the reference voltage module is used for providing a reference voltage and connecting the reference voltage to the reverse end of the comparator U1; the output end of the relay front-end voltage detection module is connected with the same-direction end of the comparator U1; the output end of the comparator U1 is connected with the power supply end Vctrl of the relay K1. In the utility model, when the output voltage of the front-end voltage detection module of the relay is larger than the preset voltage of the reference voltage module, the comparator U1 outputs a high level to supply power to the relay K1, and then the relay is closed, so that the reverse current generated when the battery pack opens the charging MOS can be effectively reduced.

Description

Current protection circuit is prevented flowing backward by battery package for charging ware

Technical Field

The utility model relates to the field of power supplies, in particular to a battery pack backflow-preventing current protection circuit for a charger, which is realized aiming at a high-power supply.

Background

The conventional circuit of the charger output end is shown in fig. 1, wherein Vo is the output of the main circuit of the charger, 12V is the output end of the auxiliary power supply of the charger, c+ is connected with a charging port of the battery pack, bat-is connected with a negative electrode of the battery pack, COM port is connected with a signal end of the battery pack, and s_g is the ground wire of the output end. The relay K1 is directly powered by 12V generated by the auxiliary power supply of the charger, and when the relay K1 is opened, the power supply starts to charge the battery.

However, at the moment of electrification of the charger, the voltage on the electrolytic capacitor at the front end of the relay does not start to rise, the 12V voltage generated by the auxiliary power supply is already used for closing the relay, and meanwhile, the charging MOS on the battery pack protection plate is opened, so that a large reverse current can be generated, and the protection plate charging MOS is damaged.

Therefore, a protection circuit is needed to solve the problem of the reverse current.

Disclosure of utility model

The utility model aims to solve the problem that a protection board charging MOS is damaged due to reverse current generated at the moment of electrification of a charger, and provides a battery pack reverse current prevention protection circuit for the charger.

The technical scheme of the utility model is as follows:

The utility model provides a battery pack anti-backflow current protection circuit for a charger, which comprises:

The reference voltage module is used for providing reference voltage, and the output end of the reference voltage module is connected with the reverse end of the comparator U1;

The relay front-end voltage detection module comprises resistors R452 and R453, wherein one end of the resistor R452 is connected with the positive electrode of the relay K1 front-end electrolytic capacitor EC401, namely the output voltage Vo of the main circuit of the charger, the other end of the resistor R452 is connected with one end of the resistor R453, the connection point is used as the output of a detection circuit and is connected with the homodromous end of the comparator U1, and the other end of the resistor R453 is grounded;

And the reverse and same-direction ends of the comparator U1 are respectively connected with the outputs of the reference voltage module and the relay front-end voltage detection module, and the output of the comparator U1 is connected with the power supply end Vctrl-K1 of the relay K1.

Further, the reference voltage module comprises a comparator U1, resistors R445 and R446;

One end of the resistor R445 is connected with a 5V auxiliary power supply of the charger, the other end of the resistor R445 is connected with the resistor R446 in series and then grounded, the connection point of the resistors R445 and R446 is connected with the reverse end of the comparator U1, and the connection point is used as the output of the reference voltage module and is connected with the reverse end of the comparator U1;

the power supply end of the comparator U1 is connected with a 12V auxiliary power supply of the charger, and the output end of the comparator U1 is connected with the power supply end Vctrl-K1 of the relay K1, so that the on-off of the relay is controlled.

The utility model has the beneficial effects that:

In the utility model, the relay K1 is not driven by 12V voltage generated by an auxiliary power supply of a charger, but a voltage signal is generated by the 358 operational amplifier comparator U1, so as to control the on and off of the relay K1.

When the utility model is used, the voltage on the electrolytic capacitor EC401 output before the relay is obtained through the voltage detection module at the front end of the relay, and when the voltage on the electrolytic capacitor is controlled to be larger than the preset voltage of the reference voltage module through setting the ratio of the resistors R452 and R453, the pin 7 of the comparator U1 is enabled to output a high level to supply power to the relay K1, and then the relay is closed, so that the reverse current generated when the charging MOS is opened by the battery pack can be effectively reduced.

Additional features and advantages of the utility model will be set forth in the detailed description which follows.

Drawings

The foregoing and other objects, features and advantages of the utility model will be apparent from the following more particular descriptions of exemplary embodiments of the utility model as illustrated in the accompanying drawings wherein like reference numbers generally represent like parts throughout the exemplary embodiments of the utility model.

Fig. 1 shows a prior art circuit diagram.

Fig. 2 shows a circuit diagram of the present utility model.

Detailed Description

Preferred embodiments of the present utility model will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present utility model are shown in the drawings, it should be understood that the present utility model may be embodied in various forms and should not be limited to the embodiments set forth herein.

Working principle:

The foregoing description of embodiments of the utility model has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described.

Claims

1. A reverse current protection circuit for a battery pack for a charger, the circuit comprising:

2. The battery pack anti-reverse current protection circuit for a charger according to claim 1, wherein the reference voltage module comprises a comparator U1, resistors R445, R446;