CN105162078B - The charge protector and method and terminal of a kind of terminal - Google Patents

Abstract

The invention discloses a charging protection circuit of a terminal, a method thereof and a terminal. The charging protection circuit comprises: a cell voltage detection module integrated in a battery chip for detecting the voltage of the battery chip; a control module connected with the battery chip The voltage detection module is connected to generate a load protection command when it is recognized that the detected voltage is greater than the first set threshold value; the load protection switch is connected between the battery chip and the load, and is connected to the control module for disconnecting the power supply from the battery chip to the load according to the load protection instruction. The invention detects the voltage of the battery chip through the cell voltage detection module, and the control module judges and generates a load protection command according to the detected voltage, and then protects the load through the load protection switch, and cuts off the cell and the load when abnormal high voltage occurs to protect the load from being damaged.

Description

A charging protection circuit and method for a terminal, and a terminal

technical field

The embodiments of the present invention relate to the field of electronic technology, and in particular, to a charging protection circuit and method for a terminal, and a terminal.

Background technique

Due to the advantages of high energy, high battery voltage, wide working range and long storage life, lithium-ion batteries have been widely used in military and civilian small electrical appliances, such as mobile phones, portable computers, video cameras and cameras, etc., partially replacing traditional batteries. Battery. However, due to its physical characteristics, lithium batteries have strict requirements on charging current, discharging current, voltage and temperature during use. Once exceeded, it will have serious consequences in terms of safety and life. Therefore, during the charging and discharging process of lithium-ion batteries, key parameters such as overcharge voltage, overdischarge voltage, charge limit current, and discharge current need to be detected and controlled to prevent excessive battery loss and ensure safety during use.

At present, the battery protection board includes functions such as overcharge protection, overdischarge protection, charging overcurrent, and discharging overcurrent. Because the mobile phone may encounter overvoltage when charging, the mobile phone charging circuit has added an overvoltage protection function. Generally, an overvoltage protection chip is added in the front stage. When a certain upper limit is reached, the charging input is automatically turned off to realize overvoltage protection for the circuit.

However, when the battery cell has abnormal high voltage or the cell side is abnormally connected to high voltage, the high voltage of the battery part will be directly supplied to the load using the power supply. When the voltage reaches a certain value, the load may be damaged. At the same time, the excessive voltage will also damage the Components in the circuit are damaged.

Contents of the invention

The invention provides a terminal charging protection circuit, method and terminal, so as to effectively protect the load when the battery core has abnormal high voltage.

For reaching this purpose, the present invention adopts following technical scheme:

In the first aspect, an embodiment of the present invention provides a charging protection circuit for a terminal, including

Cell voltage detection module, integrated inside the battery chip, used to detect the voltage of the battery chip;

The control module is connected to the cell voltage detection module, and is used to generate a load protection instruction when it is recognized that the detected voltage is greater than the first set threshold value;

A load protection switch, connected between the battery chip and the load, and connected to the control module, is used for disconnecting the power supply from the battery chip to the load according to the load protection instruction.

In the second aspect, the embodiment of the present invention also provides a terminal charging protection method, including:

Detecting the voltage of the battery chip through the cell voltage detection module;

When it is recognized by the control module that the detected voltage is greater than the first set threshold value, a load protection instruction is generated;

The load protection instruction is transmitted to the load protection switch, so as to control the load protection switch to cut off the power supply of the battery chip to the load according to the load protection instruction.

In a third aspect, an embodiment of the present invention further provides a terminal, including a battery and a battery chip, and also includes the charging protection circuit of the terminal described in the first aspect.

The invention detects the voltage of the battery chip through the cell voltage detection module, and the control module judges and generates a load protection command according to the detected voltage, and then protects the load through the load protection switch, and cuts off the cell and the load when abnormal high voltage occurs. to protect the load from being damaged.

Description of drawings

In order to illustrate the technical solutions of the exemplary embodiments of the present invention more clearly, the following briefly introduces the drawings used in describing the embodiments. Apparently, the drawings introduced are only the drawings of a part of the embodiments to be described in the present invention, rather than all the drawings. Those of ordinary skill in the art can also obtain the Other attached drawings.

FIG. 1 is a schematic structural diagram of a terminal charging protection circuit provided by Embodiment 1 of the present invention;

FIG. 2 is a schematic structural diagram of a terminal charging protection circuit provided by Embodiment 2 of the present invention;

FIG. 3 is a schematic structural diagram of a terminal charging protection circuit provided by Embodiment 3 of the present invention;

FIG. 4 is a schematic flowchart of a charging protection method for a terminal provided in Embodiment 4 of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention. In addition, it should be noted that, for the convenience of description, only some structures related to the present invention are shown in the drawings but not all structures.

Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although the flowcharts describe the steps as sequential processing, many of the steps may be performed in parallel, concurrently, or simultaneously. Additionally, the order of the various steps can be rearranged. The process may be terminated when its steps are complete, but may also have additional steps not included in the figure. The processing may correspond to a method, function, procedure, subroutine, subroutine, or the like.

Embodiment one

Figure 1 is a schematic diagram of a terminal charging protection circuit structure provided by Embodiment 1 of the present invention. This circuit structure can be applied to any terminal that needs to provide charging protection. As shown in Figure 1, the structure specifically includes: battery voltage detection module 110 , control module 120 and load protection switch 130 .

Wherein, the battery cell voltage detection module 110 is integrated inside the battery chip and is used to detect the voltage of the battery chip; the control module 120 is connected to the battery cell voltage detection module and is used to identify that the detected voltage is greater than the first set threshold limit value, a load protection instruction is generated; the load protection switch 130 is connected between the battery chip and the load, and is connected to the control module 120, and is used to disconnect the battery chip from the load to the load according to the load protection instruction. power supply.

Exemplarily, the first set threshold value is 6V-7V, preferably 6.5V. The load protection switch adopts a metal-oxide-semiconductor field effect transistor (Metal-Oxid-Semiconductor field effect transistor, MOS transistor) connected in series with a diode. Further, when the cell voltage detection module 110 detects that the cell voltage is higher than the first set threshold value (U1), the V1MOS transistor is turned off, cutting off the power connection between the battery chip and the load, so as to protect the load from damage.

A terminal charging protection circuit provided by Embodiment 1 of the present invention detects the voltage of the battery chip through the battery voltage detection module, and the control module generates a load protection command according to the detected voltage, and then performs load protection through the load protection switch. Protection, when abnormal high voltage occurs, cut off the power connection between the battery core and the load, so as to protect the load from damage.

Embodiment two

Fig. 2 is a schematic structural diagram of a terminal charging protection circuit provided by Embodiment 2 of the present invention. Further, an embodiment of the present invention provides an overcharge protection circuit structure, as shown in Fig. 2 , the structure specifically includes: Core voltage detection module 110 , control module 120 and overcharge protection switch 140 .

Wherein, the battery cell voltage detection module 110 is integrated inside the battery chip and is used to detect the voltage of the battery chip; the control module 120 is connected to the battery cell voltage detection module and is used to identify that the detected voltage is greater than the second set threshold limit value, an overcharge protection command is generated; the overcharge protection switch 140 is connected between the battery chip and the charging interface, and is connected to the control module 120, and is used to disconnect the battery according to the overcharge protection command. The charging interface charges the battery chip.

Exemplarily, the second set threshold value is 4V-4.5V, preferably 4.35V. The overcharge protection switch adopts a MOS transistor connected in series with a diode. Further, when the cell voltage detection module 110 detects that the cell voltage is higher than the second set threshold value (U2), the V2MOS transistor is turned off, the connection between the cell and the charging interface is cut off, and the charging is stopped to realize the overcharge protection function . Further, in the overcharge protection state, the body diode of V2 can still conduct, so that the battery can supply power to the load.

A terminal charging protection circuit provided by Embodiment 2 of the present invention detects the voltage of the battery chip through the cell voltage detection module, and the control module generates an overcharge protection command according to the detected voltage, and then realizes it through the overcharge protection switch Overcharge protection function, in the overcharge protection state, the body diode of V2 can still conduct, so that the battery can supply power to the load.

Embodiment Three

Fig. 3 is a schematic structural diagram of a terminal charging protection circuit provided by Embodiment 3 of the present invention. further optimization.

As shown in FIG. 3 , the battery cell voltage detection module 110 is integrated in a battery chip, and the battery chip can be installed in a battery pack or an application system. The control module 120 is connected to the cell voltage detection module 110, and when it is recognized that the voltage detected by the cell voltage detection module 110 is greater than the first set threshold value, it acts on the load protection switch 130 by generating a load protection command. When the voltage detected by the cell voltage detection module 110 is greater than the second set threshold value, an overcharge protection command is generated to act on the overcharge protection switch 140. Further, the load protection switch 130 is connected in series with the overcharge protection switch 140 Setting, the load protection switch 130 is connected between the battery chip and the load, the overcharge protection switch 140 is connected between the battery chip and the charging interface, and further, the load protection switch 130 and the overcharge protection switch 140 respectively adopt a MOS with a diode connected in series Tubes V1 and V2.

Exemplarily, the first set threshold value is greater than the second set threshold value. When charging starts, the V1MOS tube and V2MOS tube are both in the open state, and the body diodes of V1 and V2 can be turned on. It should be noted that the body diodes of V1 and V2 are in opposite directions and are used for charging and charging respectively. discharge situation. When the cell voltage detection module detects that the cell voltage is less than the second set threshold value, the battery can be charged normally and the load can be discharged normally to ensure the normal use of the load; when the cell voltage detection module detects that the cell voltage When it is greater than the second set threshold value and less than the first set threshold value, the V1MOS tube is turned on at this time, and the V2MOS tube is turned off. At this time, the battery is no longer charged but can discharge the load normally to ensure the normal use of the load; when the battery When the cell voltage detection module detects that the cell voltage is greater than the first set threshold value, it judges that there is an abnormal high voltage at the cell end, and continuing to supply power to the load may damage the load. At this time, the V1MOS tube is turned off to cut off the connection between the cell and the load. The power connection between them protects the load from being damaged.

Further, the charging protection circuit further includes a resistor R1 and a capacitor C1, both of which protect the circuit.

A terminal charging protection circuit provided by Embodiment 3 of the present invention detects the voltage of the battery chip through the cell voltage detection module, and the control module generates a load protection instruction or an overcharge protection instruction according to the detected voltage, and then through the load protection Switch or overcharge protection switch to control the opening or closing of VI MOS tube or V2MOS tube to realize load protection function or overcharge protection function. When abnormal high voltage occurs, cut off the power connection between the cell and the load to protect the load from being damaged; in the overcharge protection state, the body diode of V2 can still conduct, so that the battery can supply power to the load; when the cell voltage is less than When the second threshold value is set, the battery can be charged and discharged normally at this time.

Embodiment Four

FIG. 4 is a schematic flowchart of a terminal charging protection method provided by Embodiment 4 of the present invention. The charging protection method can be applied to any charging protection circuit and any terminal that needs to provide charging protection. As shown in Figure 4, the method specifically includes:

S210. Detect the voltage of the battery chip through the cell voltage detection module;

S220. Generate a load protection instruction when it is recognized by the control module that the detected voltage is greater than the first set threshold value;

Exemplarily, the first set threshold value is 6V-7V, preferably 6.5V. When it is recognized that the detected voltage is greater than the first set threshold value, the default is that the battery cell has abnormal high voltage or The high voltage is abnormally connected to the cell side, and a load protection command is generated.

S230. Transmit the load protection instruction to a load protection switch, so as to control the load protection switch to disconnect the power supply from the battery chip to the load according to the load protection instruction.

Exemplarily, the load protection switch adopts a MOS transistor V1 connected in series with a diode. When the MOS transistor receives a load protection command, the V1 MOS transistor is turned off to cut off the power supply connection between the battery cell and the load to protect the load from damage.

Further, the charging protection method also includes:

If it is recognized by the control module that the detected voltage is greater than the second set threshold value, an overcharge protection instruction is generated;

Exemplarily, the second set threshold value is 4V-4.5V, preferably 4.35V, when it is identified that the detected voltage is greater than the second set threshold value and less than the first set threshold value, At this time, the default is to reach the overvoltage protection point, and an overcharge protection command is generated.

The overcharge protection instruction is transmitted to the overcharge protection switch, so as to control the overcharge protection switch to disconnect the charging port from charging the battery chip according to the overcharge protection instruction.

Exemplarily, the overcharge protection switch adopts a MOS transistor V2 connected in series with a diode. When the MOS transistor receives an overcharge protection command, the V2MOS transistor is turned off, cuts off the connection between the battery cell and the charging interface, stops charging, and realizes overcharging. Charge protection function. Further, in the overcharge protection state, the body diode of V2 can still conduct, so that the battery can supply power to the load.

Further, if it is recognized by the control module that the detected voltage is less than the second set threshold value, then both the V1MOS transistor and the V2MOS transistor are in the open state, and both the body diode of V1 and the body diode of V2 can be turned on, At this time, the battery can be charged normally and the load can be discharged normally to ensure the normal use of the load.

A terminal charging protection method provided by Embodiment 4 of the present invention detects the voltage of the battery chip through the battery cell voltage detection module, recognizes the detected voltage through the control module and judges to generate a load protection command or an overcharge protection command, and then the load The protection instruction or the overcharge protection instruction is transmitted to the corresponding load protection switch or overcharge protection switch to realize the load protection function or the overcharge protection function. When abnormal high voltage occurs, cut off the power connection between the cell and the load to protect the load from being damaged; in the overcharge protection state, the body diode of V2 can still conduct, so that the battery can supply power to the load; when the cell voltage is less than When the second threshold value is set, the battery can be charged and discharged normally at this time. Different working states are judged by detecting the voltage of the battery chip, and then different circuit functions are realized.

An embodiment of the present invention also provides a terminal, the terminal specifically includes: a battery and a battery chip, and also includes the charging protection circuit of the terminal mentioned in any embodiment of the present invention.

Specifically, the battery chip needs to detect and control key parameters such as the overcharge voltage, overdischarge voltage, charge limit current, and discharge current of the battery, so as to prevent excessive battery loss and ensure the safety of the battery and its terminal use. .

Further, the terminal may be a mobile phone, a tablet computer or other terminal equipment that needs to provide charging protection.

The terminal provided by the embodiment of the present invention is used for the charging protection method provided by the embodiment of the present invention. The charging protection circuit provided by the embodiment of the present invention is used to achieve the purpose of charging protection. It has corresponding functional modules and beneficial Effect. For technical details not described in detail in this embodiment, reference may be made to the circuits and methods provided in the above embodiments of the present invention.

Note that the above are only preferred embodiments of the present invention and applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and can also include more other equivalent embodiments without departing from the concept of the present invention, and the present invention The scope is determined by the scope of the appended claims.

Claims (3)

1. A terminal charging protection circuit, characterized in that, comprising: Cell voltage detection module, integrated inside the battery chip, used to detect the voltage of the battery chip; The control module is connected to the cell voltage detection module, and is used to generate a load protection command when it is recognized that the detected voltage is greater than the first set threshold value, that is, when the cell side is abnormally connected to a high voltage; The control module is also used to generate an overcharge protection command when it recognizes that the detected voltage is greater than the second set threshold value; Wherein, the first set threshold value is 6.5V; the second set threshold value is 4.35V; A load protection switch, connected between the battery chip and the load, and connected to the control module, for disconnecting the power supply from the battery chip to the load according to the load protection instruction; The circuit also includes an overcharge protection switch, connected between the battery chip and the charging interface, and connected to the control module, for disconnecting the charging interface from charging the battery chip according to the overcharge protection instruction ; Wherein, the load protection switch and the overcharge protection switch adopt metal-oxide-semiconductor field effect transistors respectively, and a diode is connected in parallel between the source and the drain of the field effect transistor, wherein the anode of the diode is connected to the The source of the field effect transistor is electrically connected, and the cathode of the diode is electrically connected to the drain of the field effect transistor. 2. A load protection terminal, comprising a battery and a battery chip, further comprising the charging protection circuit of the terminal according to claim 1. 3. A charging protection method for a terminal, characterized in that it is performed by the terminal according to claim 2, the method comprising: Detect the voltage of the battery chip through the cell voltage detection module; When the control module recognizes that the detected voltage is greater than the first set threshold value, that is, when the battery side is abnormally connected to high voltage, a load protection command is generated; transmitting the load protection instruction to the load protection switch, so as to control the load protection switch to disconnect the power supply from the battery chip to the load according to the load protection instruction; If it is recognized by the control module that the detected voltage is greater than the second set threshold value, an overcharge protection instruction is generated; Transmitting the overcharge protection instruction to the overcharge protection switch, so as to control the overcharge protection switch to disconnect the charging interface from charging the battery chip according to the overcharge protection instruction; Wherein, the first set threshold value is 6.5V; the second set threshold value is 4.35V; Wherein, the load protection switch and the overcharge protection switch adopt metal-oxide-semiconductor field effect transistors respectively, and a diode is connected in parallel between the source and the drain of the field effect transistor, wherein the anode of the diode is connected to the The source of the field effect transistor is electrically connected, and the cathode of the diode is electrically connected to the drain.