Battery protection chip, battery protection circuit and battery

Abstract

The utility model discloses a battery protection chip, a battery protection circuit and a battery, the battery protection chip comprises a reference voltage input pin, a comparison circuit and a controller, the reference voltage input pin is electrically connected with a first input end of the comparison circuit; the reference voltage input pin is used for being connected with an external reference voltage providing circuit; the output end of the comparison circuit is electrically connected with the controller; the second input end of the comparison circuit is electrically connected with an over-current detection pin of the battery protection chip, or the second input end of the comparison circuit is electrically connected with a cell voltage detection pin of the battery protection chip through a first voltage division circuit.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a battery protection chip, a battery protection circuit and a battery. Background Art

[0002] Lithium batteries are widely used in various electronic devices due to their high energy density, long service life, high rated voltage, and environmental protection. In order to avoid overcharging and overdischarging of lithium batteries during use, which may lead to safety hazards, it is usually necessary to set a battery protection chip to ensure the safety of battery use.

[0003] However, the protection voltage in the current battery protection chip is a fixed value. As long as the voltage system of the lithium battery is adjusted, the corresponding battery protection chip needs to be adjusted accordingly. The battery protection chip has the problem of poor versatility. Utility Model Content

[0004] The present application discloses a battery protection chip, a battery protection circuit and a battery, which can improve the versatility of the battery protection chip.

[0005] In a first aspect, an embodiment of the present application discloses a battery protection chip, comprising: a reference voltage input pin, a comparison circuit and a controller, wherein: the reference voltage input pin is electrically connected to the first input end of the comparison circuit, and the reference voltage input pin is used to connect an external reference voltage providing circuit; the output end of the comparison circuit is electrically connected to the controller; the second input end of the comparison circuit is electrically connected to the overcurrent detection pin of the battery protection chip, or the second input end of the comparison circuit is electrically connected to the cell voltage detection pin of the battery protection chip through a first voltage divider circuit.

[0006] In a second aspect, an embodiment of the present application discloses a battery protection circuit, comprising an external reference voltage providing circuit and the battery protection chip described in the first aspect, wherein the external reference voltage providing circuit is electrically connected to a reference voltage input pin of the battery protection chip.

[0007] In a third aspect, an embodiment of the present application discloses a battery, comprising the battery protection circuit described in the second aspect.

[0008] The embodiment of the present application provides a battery protection chip, which includes a reference voltage input pin, a comparison circuit and a controller, wherein the reference voltage input pin is electrically connected to the first input terminal of the comparison circuit, the reference voltage input pin is used to connect to an external reference voltage providing circuit, the output terminal of the comparison circuit is electrically connected to the controller, the second input terminal of the comparison circuit is electrically connected to the overcurrent detection pin of the battery protection chip, or the second input terminal of the comparison circuit is electrically connected to the cell voltage detection pin of the battery protection chip through a first voltage divider circuit. By adopting the scheme provided by the present application, a reference voltage (i.e., protection voltage) for comparison is provided to the comparison circuit in the battery protection chip by an external reference voltage providing circuit provided outside the battery protection chip. If the battery voltage system is adjusted, it is only necessary to adjust the external reference voltage providing circuit accordingly to adjust the reference voltage for comparison, and there is no need to adjust the battery protection chip, which can improve the versatility of the battery protection chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a schematic diagram of the structure of the first battery protection chip disclosed in the embodiment of the present application;

[0010] Figure 2 This is a schematic diagram of the structure of the second battery protection chip disclosed in the embodiment of the present application;

[0011] Figure 3 This is a schematic diagram of the structure of the first battery protection circuit disclosed in the embodiment of the present application;

[0012] Figure 4 A schematic diagram of the structure of a voltage regulation circuit disclosed in an embodiment of the present application;

[0013] Figure 5 A partial structural diagram of a battery protection circuit disclosed in an embodiment of the present application;

[0014] Figure 6 A schematic diagram of the structure of a second battery protection circuit disclosed in an embodiment of the present application;

[0015] Figure 7 A schematic diagram of the structure of a battery disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0017] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way are interchangeable where appropriate, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0018] The present application discloses a battery protection chip, a battery protection circuit and a battery. Figure 1 A schematic diagram of the structure of a battery protection chip disclosed in an embodiment of the present application.

[0019] like Figure 1 As shown, the battery protection chip disclosed in the present application includes: a reference voltage input pin REF, a comparison circuit 110 and a controller 120, wherein: the reference voltage input pin REF is electrically connected to the first input end of the comparison circuit 110, and the reference voltage input pin REF is used to connect an external reference voltage providing circuit 200; the output end of the comparison circuit 110 is electrically connected to the controller 120; the second input end of the comparison circuit 110 is electrically connected to the overcurrent detection pin VINI of the battery protection chip, or the second input end of the comparison circuit 110 is electrically connected to the cell voltage detection pin VDD of the battery protection chip through the first voltage divider circuit 150.

[0020] The comparison circuit 110 in the present application has the following features: Figure 1 Two connection methods are shown.

[0021] The first type is: the battery protection chip includes a reference voltage input pin REF, a comparison circuit 110 and a controller 120, the first input end of the comparison circuit 110 is electrically connected to the reference voltage input pin REF, the second input end of the comparison circuit 110 is electrically connected to the overcurrent detection pin VINI of the battery protection chip, the output end of the comparison circuit 110 is electrically connected to the controller 120, the comparison circuit 110 compares the voltage input through the VINI pin and the REF pin, and sends a comparison signal to the controller 120, and the controller 120 performs corresponding protection operations according to the received comparison signal.

[0022] The second type is: the battery protection chip includes a reference voltage input pin REF, a comparison circuit 110, a controller 120 and a first voltage divider circuit 150. The first input end of the comparison circuit 110 is electrically connected to the reference voltage input pin REF, the second input end of the comparison circuit 110 is electrically connected to the cell voltage detection pin VDD of the battery protection chip through the first voltage divider circuit 150, and the output end of the comparison circuit 110 is electrically connected to the controller 120. In the present application, the first voltage divider circuit 150 is used to divide the voltage input through the VDD pin. The comparison circuit 110 compares the voltage output by the first voltage divider circuit 150 with the voltage input through the REF pin, and sends a comparison signal to the controller 120. The controller 120 performs corresponding protection operations according to the received comparison signal.

[0023] In an embodiment of the present application, a reference voltage input pin REF is added to the battery protection chip, the first input end of the comparison circuit 110 in the battery protection chip is electrically connected to the reference voltage input pin REF, and the reference voltage input pin REF is electrically connected to an external reference voltage providing circuit 200 outside the battery protection chip. The external reference voltage providing circuit 200 provides a reference voltage (i.e., a protection voltage) for comparison to the comparison circuit 110. When this solution is adopted, if the battery voltage system is adjusted, it is only necessary to adjust the external reference voltage providing circuit 200 accordingly to adjust the reference voltage for comparison, and there is no need to adjust the battery protection chip. This can improve the versatility of the battery protection chip, avoid inventory stagnation caused by frequent updates of the battery protection chip, and facilitate management.

[0024] The embodiment of the present application provides a battery protection chip, which includes a reference voltage input pin REF, a comparison circuit 110 and a controller 120, the reference voltage input pin REF is electrically connected to the first input end of the comparison circuit 110, the reference voltage input pin REF is used to connect to an external reference voltage providing circuit 200, the output end of the comparison circuit 110 is electrically connected to the controller 120, the second input end of the comparison circuit 110 is electrically connected to the overcurrent detection pin VINI of the battery protection chip, or the second input end of the comparison circuit 110 is electrically connected to the cell voltage detection pin VDD of the battery protection chip through the first voltage divider circuit 150. Using the solution provided by the present application, the reference voltage (i.e., protection voltage) for comparison is provided to the comparison circuit 110 in the battery protection chip by an external reference voltage providing circuit 200 provided outside the battery protection chip. If the battery voltage system is adjusted, it is only necessary to adjust the external reference voltage providing circuit 200 accordingly to adjust the reference voltage for comparison, and there is no need to adjust the battery protection chip, which can improve the versatility of the battery protection chip.

[0025] In the present application, the above-mentioned comparison circuit 110 can be one of a comparison circuit for overcharge detection, a comparison circuit for overdischarge detection, a comparison circuit for discharge overcurrent detection, a comparison circuit for short-circuiting detection, and a comparison circuit for charge overcurrent detection. That is to say, the reference voltage used for comparison in the comparison circuits used to implement overcharge detection, overdischarge detection, discharge overcurrent detection, short-circuiting detection, and charge overcurrent detection in the battery protection chip can be provided by an external reference voltage providing circuit 200 arranged outside the battery protection chip through the reference voltage input pin REF of the battery protection chip.

[0026] Among them, the comparison circuit for discharge over current detection, the comparison circuit for short circuit detection and the comparison circuit for charge over current detection are connected according to the first connection method of the comparison circuit described above, that is, the second input end of the comparison circuit is electrically connected to the overcurrent detection pin VINI of the battery protection chip, and the comparison circuit for over charge detection and the comparison circuit for over discharge detection are connected according to the second connection method of the comparison circuit described above, that is, the second input end of the comparison circuit is electrically connected to the cell voltage detection pin VDD of the battery protection chip through the first voltage divider circuit 150.

[0027] In the embodiment of the present application, there may be multiple reference voltage input pins REF, and there may be multiple comparison circuits 110. In one implementation, the number of reference voltage input pins REF may be equal to the number of comparison circuits 110, and the reference voltage input pins REF correspond to the comparison circuits 110 one by one, that is, one reference voltage input pin REF is electrically connected to one comparison circuit 110. In another implementation, the number of reference voltage input pins REF may be less than the number of comparison circuits 110, that is, multiple comparison circuits 110 may be electrically connected to the same reference voltage input pin REF.

[0028] Exemplarily, the plurality of comparison circuits 110 may include a comparison circuit for overcharge detection, a comparison circuit for overdischarge detection, a comparison circuit for discharge overcurrent detection, a comparison circuit for short-circuiting detection, and a comparison circuit for charge overcurrent detection. That is to say, the reference voltages used for comparison in the various comparison circuits in the battery protection chip for implementing overcharge detection, overdischarge detection, discharge overcurrent detection, short-circuit detection, and charge overcurrent detection may all be provided by an external reference voltage providing circuit 200 disposed outside the battery protection chip through a reference voltage input pin REF of the battery protection chip.

[0029] Furthermore, the first input terminals of different comparison circuits 110 may be electrically connected to different reference voltage input pins REF, or to the same reference voltage input pin REF. In addition, the reference voltages provided by different reference voltage input pins REF may be the same or different.

[0030] In one embodiment, Figure 2 As shown, the comparison circuit 110 may include a comparator, wherein: the first input terminal of the comparator is electrically connected to the reference voltage input pin REF; the output terminal of the comparator is electrically connected to the controller 120; the second input terminal of the comparator is electrically connected to the overcurrent detection pin VINI, or the second input terminal of the comparator is electrically connected to the cell voltage detection pin VDD through the first voltage divider circuit 150. The first input terminal of the above-mentioned comparator may be the negative input terminal of the comparator, and the second input terminal of the comparator may be the positive input terminal of the comparator.

[0031] In the embodiment of the present application, the first voltage divider circuit 150 includes a first resistor 130 and a second resistor 140, the first end of the first resistor 130 is electrically connected to the cell voltage detection pin VDD, the second end of the first resistor 130 is electrically connected to the first end of the second resistor 140, the second end of the second resistor 140 is grounded, and the second input end of the comparison circuit 110 is electrically connected to the second end of the first resistor 130. In this case, by adjusting the resistance values ​​of the first resistor 130 and the second resistor 140, different input voltages can be provided to the second input end of the comparison circuit 110.

[0032] It should be noted that the VSS pin of the battery protection chip in the drawings of the present application is a common ground pin, the VM pin is a detection pin for the charger and load, the CO pin is a pin for controlling the charging MOS, and the DO pin is a pin for controlling the discharging MOS.

[0033] like Figure 3 As shown, an embodiment of the present application discloses a battery protection circuit, which includes an external reference voltage providing circuit 200 and the battery protection chip described above, wherein the external reference voltage providing circuit 200 is electrically connected to a reference voltage input pin REF of the battery protection chip.

[0034] An embodiment of the present application provides a battery protection circuit, in which an external reference voltage providing circuit 200 arranged outside the battery protection chip provides a reference voltage for comparison (i.e., a protection voltage) to a comparison circuit 110 in the battery protection chip through a reference voltage input pin REF of the battery protection chip. If the battery voltage system is adjusted, it is only necessary to adjust the external reference voltage providing circuit 200 accordingly to adjust the reference voltage for comparison, and there is no need to adjust the battery protection chip, thereby improving the versatility of the battery protection chip.

[0035] In one implementation, the external reference voltage providing circuit 200 may include a voltage regulating circuit 210. That is, the external reference voltage providing circuit 200 may provide an adjustable reference voltage.

[0036] In the embodiments of the present application, Figure 4 As shown, the voltage regulating circuit 210 may include a boost circuit 211 and a second voltage divider circuit 212, the output end of the boost circuit 211 is electrically connected to the input end of the second voltage divider circuit 212, and the output end of the second voltage divider circuit 212 is electrically connected to the reference voltage input pin REF. In other words, a standard voltage VREF can be obtained as a reference through the boost circuit 211, and then a reference voltage that should be input to the reference voltage input pin REF of the battery protection chip can be obtained through the second voltage divider circuit 212.

[0037] In the embodiments of the present application, Figure 4 As shown, the second voltage divider circuit 212 may include a third resistor 2121 and a fourth resistor 2122, the output end of the boost circuit 211 is electrically connected to the first end of the third resistor 2121, the second end of the third resistor 2121 is electrically connected to the first end of the fourth resistor 2122, the second end of the fourth resistor 2122 is grounded, and the reference voltage input pin REF is electrically connected to the second end of the third resistor 2121. In the case where the second voltage divider circuit 212 includes the third resistor 2121 and the fourth resistor 2122, by adjusting the resistance value of the third resistor 2121 and the resistance value of the fourth resistor 2122, different reference voltages can be provided to the reference voltage input pin REF of the battery protection chip, corresponding to different protection requirements of different voltage systems.

[0038] Optionally, the third resistor 2121 and the fourth resistor 2122 may be fixed-value resistors. In this case, the resistance of the third resistor 2121 and the resistance of the fourth resistor 2122 may be adjusted by replacing the models of the third resistor 2121 and the fourth resistor 2122.

[0039] Optionally, the third resistor 2121 may be an adjustable resistor, and the fourth resistor 2122 may be an adjustable resistor. In this case, the resistance value of the third resistor 2121 and the resistance value of the fourth resistor 2122 may be directly adjusted without changing the resistor model, which is convenient to operate.

[0040] In the embodiment of the present application, the boost circuit 211 may adopt a boost circuit in the prior art, and the present application does not impose any specific limitation on this.

[0041] In the embodiments of the present application, Figure 5 As shown, the battery protection chip includes reference voltage input pins REF1 and REF2, R2 is used as the third resistor 2121, R3 is used as the fourth resistor 2122, and a second voltage divider circuit is formed, R4 is used as the third resistor 2121, and R5 is used as the fourth resistor 2122 to form another second voltage divider circuit, the voltage VREF output by the boost circuit 211 is input to the REF1 pin after being divided by R2 and R3, and the voltage VREF output by the boost circuit 211 is input to the REF2 pin after being divided by R4 and R5. That is, the output end of a boost circuit 211 can be electrically connected to the input end of different second voltage divider circuits 212, and the output end of each second voltage divider circuit 212 is electrically connected to a reference voltage input pin.

[0042] In another implementation, Figure 6 As shown, the external reference voltage providing circuit 200 may include a voltage source 220, the positive electrode of the voltage source 220 is electrically connected to the reference voltage input pin, and the negative electrode of the voltage source 220 is grounded. In other words, the reference voltage may be directly provided to the reference voltage input pin REF of the battery protection chip through the voltage source 220. In this case, the model of the voltage source 220 may be changed to correspond to different protection requirements of different voltage systems.

[0043] An embodiment of the present application discloses a battery, which includes the battery protection circuit described above.

[0044] like Figure 7 As shown, the battery may include a battery protection chip U1 and a battery protection chip U2. Both the battery protection chip U1 and the battery protection chip U2 include a reference voltage input pin. The battery protection chip U1 and the battery protection chip U2 are electrically connected to an external reference voltage providing circuit through the reference voltage input pin.

[0045] In addition, the battery may further include a battery cell, a metal-oxide-semiconductor field effect transistor (MOS tube) and a connector.

[0046] The above embodiments of the present application focus on describing the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, they will not be repeated here.

[0047] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A battery protection chip, characterized in that: include: Reference voltage input pin, comparison circuit and controller, where: The reference voltage input pin is electrically connected to the first input terminal of the comparison circuit, and the reference voltage input pin is used to connect to an external reference voltage providing circuit; The output end of the comparison circuit is electrically connected to the controller; The second input end of the comparison circuit is electrically connected to the overcurrent detection pin of the battery protection chip, or the second input end of the comparison circuit is electrically connected to the cell voltage detection pin of the battery protection chip through the first voltage divider circuit.

2. The battery protection chip according to claim 1, characterized in that: There are a plurality of reference voltage input pins and a plurality of comparison circuits, and one reference voltage input pin is electrically connected to one comparison circuit.

3. The battery protection chip according to claim 1, characterized in that: The comparison circuit comprises a comparator, wherein: The first input terminal of the comparator is electrically connected to the reference voltage input pin; The output end of the comparator is electrically connected to the controller; The second input end of the comparator is electrically connected to the overcurrent detection pin, or the second input end of the comparator is electrically connected to the cell voltage detection pin through the first voltage divider circuit.

4. The battery protection chip according to claim 1, characterized in that: The first voltage divider circuit includes a first resistor and a second resistor, the first end of the first resistor is electrically connected to the battery cell voltage detection pin, the second end of the first resistor is electrically connected to the first end of the second resistor, the second end of the second resistor is grounded, and the second input end of the comparison circuit is electrically connected to the second end of the first resistor.

5. A battery protection circuit, characterized in that: It comprises an external reference voltage providing circuit and the battery protection chip according to any one of claims 1 to 4, wherein the external reference voltage providing circuit is electrically connected to a reference voltage input pin of the battery protection chip.

6. The battery protection circuit according to claim 5, characterized in that: The external reference voltage providing circuit includes a voltage regulating circuit.

7. The battery protection circuit according to claim 6, characterized in that: The voltage regulating circuit comprises a boost circuit and a second voltage divider circuit, wherein the output end of the boost circuit is electrically connected to the input end of the second voltage divider circuit, and the output end of the second voltage divider circuit is electrically connected to the reference voltage input pin.

8. The battery protection circuit according to claim 7, characterized in that: The second voltage divider circuit includes a third resistor and a fourth resistor, the output end of the boost circuit is electrically connected to the first end of the third resistor, the second end of the third resistor is electrically connected to the first end of the fourth resistor, the second end of the fourth resistor is grounded, and the reference voltage input pin is electrically connected to the second end of the third resistor.

9. The battery protection circuit according to claim 8, characterized in that: The third resistor is an adjustable resistor, and the fourth resistor is an adjustable resistor.

10. The battery protection circuit according to claim 5, characterized in that: The external reference voltage providing circuit comprises a voltage source, a positive electrode of the voltage source is electrically connected to the reference voltage input pin, and a negative electrode of the voltage source is grounded.

11. A battery, characterized in that: The battery protection circuit comprises the battery protection circuit according to any one of claims 5 to 10.

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