CN217882929U

CN217882929U - Battery protection circuit and intelligent door lock

Info

Publication number: CN217882929U
Application number: CN202222035423.XU
Authority: CN
Inventors: 牛帅威
Original assignee: Lumi United Technology Co Ltd
Current assignee: Lumi United Technology Co Ltd
Priority date: 2022-08-03
Filing date: 2022-08-03
Publication date: 2022-11-22
Anticipated expiration: 2032-08-03

Abstract

The embodiment of the utility model discloses battery protection circuit and intelligent lock, wherein, battery protection circuit includes temperature module, current module, battery control module, wherein: the temperature module is connected with a first input end of the battery control module and used for collecting the ambient temperature and outputting a first electric signal corresponding to the ambient temperature to the battery control module; one end of the current module is used for being connected with the battery, the other end of the current module is connected with the second input end of the battery control module, and the current module is used for collecting the current output by the battery and outputting a second electric signal corresponding to the current to the battery control module; the output end of the battery control module is connected with the battery and used for controlling the battery to normally output when the ambient temperature is abnormal and the current is smaller than a preset current threshold, wherein the ambient temperature is abnormal and means that the ambient temperature is higher than a first preset temperature or the ambient temperature is lower than a second preset temperature. This technical scheme can make the battery output undercurrent when high temperature, lets equipment keep normal use.

Description

Battery protection circuit and intelligent door lock

Technical Field

The utility model relates to a circuit technical field especially relates to battery protection circuit and intelligent lock.

Background

With the development of electronic products, batteries are increasingly used in electronic products. The battery is applied to various intelligent devices and used for supplying power to various functional modules in the intelligent devices so as to ensure the normal operation of the functional modules.

The discharge safety of the battery is a concern during the use of the battery. Because the battery is greatly influenced by the over-temperature, in the current battery discharge control scheme, the battery is generally turned off when the over-temperature is detected. For the intelligent door lock provided with the battery, if the battery is directly turned off when the overtemperature is detected, all functional modules of the door lock cannot be used, so that the normal use of the intelligent door lock is influenced.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model provides a battery protection circuit and intelligent lock for solve among the prior art the overtemperature and turn off the battery promptly and the unable normal use's of equipment technical problem who brings.

In a first aspect, a battery protection circuit is provided, which includes a temperature module, a current module, and a battery control module, wherein:

the temperature module is connected with a first input end of the battery control module and used for collecting the ambient temperature and outputting a first electric signal corresponding to the ambient temperature to the battery control module;

one end of the current module is used for being connected with a battery, the other end of the current module is connected with a second input end of the battery control module, and the current module is used for collecting current output by the battery and outputting a second electric signal corresponding to the current to the battery control module;

the output end of the battery control module is connected with the battery and used for controlling the battery to normally output when the ambient temperature is determined to be abnormal according to the first electric signal and the current is determined to be smaller than a preset current threshold value according to the second electric signal, wherein the abnormal ambient temperature means that the ambient temperature is higher than a first preset temperature or the ambient temperature is lower than a second preset temperature, and the second preset temperature is lower than the first preset temperature.

In one possible design; the battery control module comprises a first logic circuit and a switch; the first input end of the first logic circuit is connected with the temperature module, the second input end of the first logic circuit is connected with the other end of the current module, the output end of the first logic circuit is connected with the controlled end of the switch, and the on-off output end of the switch is connected with the battery.

In one possible design, the temperature module includes a temperature acquisition unit and a temperature judgment unit; the temperature acquisition unit is connected with one end of the temperature judgment unit and is used for acquiring the ambient temperature; the other end of the temperature judging unit is connected with a first input end of the battery control module and used for judging the ambient temperature and outputting a first electric signal corresponding to the ambient temperature to the battery control module.

In one possible design, the temperature determination unit includes a first comparison circuit, a second comparison circuit, and a second logic circuit; the input end of the first comparison circuit is connected with the temperature acquisition unit, and the output end of the first comparison circuit is connected with the first input end of the second logic circuit, and is used for judging whether the ambient temperature is higher than the first preset temperature or not and outputting a high-temperature indication signal to the second logic circuit when the ambient temperature is higher than the first preset temperature; the input end of the second comparison circuit is connected with the temperature acquisition unit, the output end of the second comparison circuit is connected with the second input end of the second logic circuit, and the second comparison circuit is used for judging whether the ambient temperature is lower than a second preset temperature or not and outputting a low-temperature indication signal to the second logic circuit when the ambient temperature is lower than the second preset temperature, and the second preset temperature is lower than the first preset temperature; the output end of the second logic circuit is connected with the first input end of the battery control module and used for outputting a first electric signal for indicating temperature abnormity to the battery control module when the high-temperature indication signal or the low-temperature indication signal is received.

In one possible design, the first comparison circuit includes a first comparator, a first resistor, and a second resistor; the non-inverting input end of the first comparator is connected with one end of the first resistor and one end of the second resistor, the other end of the first resistor is connected with a power supply, the other end of the second resistor is grounded, the inverting input end of the first comparator is connected with the temperature acquisition unit, and the output end of the first comparator is connected with the first input end of the second logic circuit; the second comparison circuit comprises a second comparator, a third resistor and a fourth resistor; the in-phase input end of the second comparator is connected with the temperature acquisition unit, the inverting input end of the second comparator is connected with one end of the third resistor and one end of the fourth resistor, the other end of the third resistor is connected with the power supply, the other end of the fourth resistor is grounded, and the output end of the second comparator is connected with the second input end of the second logic circuit.

In one possible design, the current module includes a signal amplification circuit and a third comparison circuit; one end of the signal amplification circuit is connected with the battery and is used for collecting the current output by the battery and amplifying the signal; one end of the third comparison circuit is connected with the other end of the signal amplification circuit, the other end of the third comparison circuit is connected with the second input end of the battery control module, and the third comparison circuit is used for judging whether the current is greater than the preset current threshold value according to an electric signal obtained by signal amplification and outputting a second electric signal for indicating overcurrent when the current is greater than the preset current threshold value.

In one possible design, the third comparison circuit includes a third comparator, a fifth resistor, and a sixth resistor; the in-phase input end of the third comparator is connected with the other end of the signal amplification circuit, the inverting input end of the third comparator is connected with one end of the fifth resistor and one end of the sixth resistor, the other end of the fifth resistor is connected with the power supply, the other end of the sixth resistor is grounded, and the output end of the third comparator is connected with the second input end of the battery control module.

In one possible design, the signal amplification circuit includes an operational amplifier, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, and an eleventh resistor; one end of the seventh resistor is connected with one end of the battery and one end of the eighth resistor, the other end of the seventh resistor is connected with one end of the ninth resistor, the other end of the ninth resistor is connected with one end of the tenth resistor and the inverting input end of the operational amplifier, the other end of the tenth resistor is connected with the output end of the operational amplifier and one end of the third comparison circuit, the other end of the eighth resistor is connected with one end of the eleventh resistor and the non-inverting input end of the operational amplifier, and the other end of the eleventh resistor is grounded.

In one possible design, the battery control module is further configured to stop the battery output when the ambient temperature is determined to be abnormal according to the first electrical signal and the current is determined to be greater than a preset current threshold according to the second electrical signal; and/or the battery control module is further used for controlling the battery to normally output when the environment temperature is determined to be normal according to the first electric signal, wherein the normal environment temperature means that the environment temperature is greater than or equal to the second preset temperature and is less than or equal to the first preset temperature.

In a second aspect, an intelligent door lock is provided, which comprises a battery, a load and the battery protection circuit of the first aspect.

In one possible design, the load includes a first load and a second load, and the first load and the second load are both connected to the battery and used for working based on the current output by the battery, wherein the current required by the first load to work is smaller than the preset current threshold, and the current required by the second load to work is larger than or equal to the preset current threshold; the battery protection circuit is used for controlling the battery to supply power to the first load and stop supplying power to the second load when the ambient temperature is abnormal.

Implement the embodiment of the utility model provides a, will have following beneficial effect:

the utility model provides a battery protection circuit, including temperature module, current module, battery control module and battery, wherein: the temperature module is connected with a first input end of the battery control module and used for collecting the ambient temperature and outputting a first electric signal corresponding to the ambient temperature to the battery control module; one end of the current module is used for being connected with the battery, the other end of the current module is connected with the second input end of the battery control module, and the current module is used for collecting the current output by the battery and outputting a second electric signal corresponding to the current to the battery control module; the output end of the battery control module is connected with the battery and used for controlling the battery to normally output when the ambient temperature is abnormal and the current is smaller than a preset current threshold value. Because the temperature module can export the first signal of telecommunication corresponding with ambient temperature, the second signal of telecommunication that the current module can export and electric current corresponds for battery control module can judge whether ambient temperature is greater than first preset temperature or whether be less than the second preset temperature and judge whether the electric current is less than preset current threshold value according to the second signal of telecommunication, and then be greater than first preset temperature and electric current and be less than preset current threshold value or control battery normal output when ambient temperature is less than first preset temperature and electric current and is less than preset current threshold value (be ambient temperature unusual), consequently, the utility model discloses a battery protection circuit also can maintain the undercurrent power supply of battery when ambient temperature is unusual, thereby can let equipment keep normal use.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the description below are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Wherein:

fig. 1 is a block diagram of an intelligent door lock according to an embodiment of the present disclosure;

fig. 2 is a block diagram of a battery protection circuit according to an embodiment of the present disclosure;

fig. 3 is a block diagram of a temperature module according to an embodiment of the present disclosure;

fig. 4 is a schematic circuit diagram of a temperature acquisition unit according to an embodiment of the present disclosure;

fig. 5 is a block diagram of a temperature determination unit according to an embodiment of the present application;

fig. 6 is a schematic circuit diagram of a temperature determination unit according to an embodiment of the present disclosure;

fig. 7 is a block diagram of a current module according to an embodiment of the present disclosure;

FIG. 8 is a schematic circuit diagram of a current module according to an embodiment of the present disclosure;

fig. 9 is a block diagram of a battery control module according to an embodiment of the present disclosure;

fig. 10 is a schematic circuit diagram of a battery control module according to an embodiment of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

The battery protection circuit of this application is applicable in various electronic equipment that utilize the battery to carry out the power supply, for example, cell-phone, panel computer and various intelligent device (such as intelligent lock, electric window curtain, intelligent robot etc.).

Referring to fig. 1, fig. 1 is a block diagram of an intelligent door lock according to an embodiment of the present disclosure, as shown in fig. 1, the intelligent door lock 1 may include a battery 10, a load 20, and a battery protection circuit 30, where the battery 10 is connected to the load 20 and the battery protection circuit 30. The load 20 may specifically include a fingerprint module, a password module, a face recognition module, and other power consumption modules, where the current required by the fingerprint module and the password module during operation is small, usually within 100 milliamperes (mA), and may be referred to as a first load or a low-power consumption module in the present application; the current required by the face recognition module during operation is relatively large, usually about 2 amperes (a), and the face recognition module can be called as a second load in the application and also can be called as a large-function power utilization module. The battery 10 is used for supplying power to the load 20 to ensure the normal operation of the load 20; specifically, the battery 10 may output a current corresponding to the power consumption demand to each power consumption module in the loads 20 based on the power consumption demand of each power consumption module in the loads 20, for example, the battery 10 may output a current within 100mA to the fingerprint module and the password module based on the work demand of the fingerprint module and the password module; the battery 10 may also output a current of about 2A to the face recognition module based on the operational requirements of the face recognition module. Specifically, the battery 10 may be a lithium battery. The battery protection circuit 30 is used to control the output of the battery 10 to function as protection of the battery 10; specifically, the battery protection circuit 30 may control the battery 10 to normally output the current, and may also control the battery 10 to stop outputting the current. Specifically, the battery protection circuit 30 may control the battery 10 to normally output to supply power to the first load when the ambient temperature is greater than a first preset temperature and the current output by the battery 10 is less than a preset current threshold, or when the ambient temperature is less than a second preset temperature and the current output by the battery 10 is less than the preset current threshold, where the second preset temperature is less than the first preset temperature; the battery protection circuit 30 may also be configured to stop the output of the battery 10 to stop supplying power to the second load when the ambient temperature is greater than the first preset temperature and the current output by the battery 10 is greater than the preset current threshold, or when the ambient temperature is less than the second preset temperature and the current output by the battery 10 is greater than the preset current threshold. The preset current threshold may be greater than the current required by the first load to operate, and less than or equal to the current required by the second load to operate. In this way, the battery protection circuit 30 can control the battery 10 to output normally when the ambient temperature is abnormal (the ambient temperature is high or low) and the current output by the battery is small, so that the low-power electricity-consuming module of the door lock can be used normally when the ambient temperature is abnormal, and the basic function of the door lock is ensured.

Referring to fig. 2, fig. 2 is a block diagram of a battery protection circuit according to an embodiment of the present disclosure, and as shown in fig. 2, the battery protection circuit 30 may include a temperature module 31, a current module 32, and a battery control module 33, where:

the temperature module 31 is connected to a first input end of the battery control module 33, and is configured to collect an ambient temperature and output a first electrical signal corresponding to the ambient temperature to the battery control module 33;

one end of the current module 32 is configured to be connected to the battery 10, the other end of the current module 32 is connected to a second input end of the battery control module 33, and the current module 32 is configured to collect a current output by the battery and output a second electrical signal corresponding to the current to the battery control module 33;

the output end of the battery control module 33 is connected to the battery 10, and is configured to control the battery 10 to normally output when the ambient temperature is determined to be abnormal according to the first electrical signal and the current is determined to be less than the preset current threshold according to the second electrical signal, where the abnormal ambient temperature means that the ambient temperature is higher than a first preset temperature or the ambient temperature is lower than a second preset temperature, and the second preset temperature is lower than the first preset temperature.

The temperature module 31 may be any circuit module capable of collecting an ambient temperature and outputting a first electrical signal corresponding to the ambient temperature. The first electrical signal corresponding to the ambient temperature means that the first electrical signal changes with the change of the ambient temperature. The first electrical signal may be a continuous signal, for example may be a voltage signal; the first electrical signal may also be a discrete signal, for example, a level signal. Whether the first electrical signal is a continuous signal or a discrete signal depends on the specific circuit design of the temperature module 31. Specifically, when the first electrical signal is a discrete signal, a high temperature may be indicated by a low level signal and a low temperature may be indicated by a high level signal; the low temperature can be indicated by a high level signal, and the high temperature can be indicated by a high level signal; alternatively, a low level signal may indicate a high temperature or a low temperature, or a high level signal may indicate a high temperature or a low temperature. The specific level signal used to indicate the temperature depends on the specific circuit design of the temperature module 31.

The current module 32 may be any circuit module capable of detecting the current output by the battery and outputting the second electrical signal corresponding to the current output by the battery. The meaning of the second electrical signal corresponding to the current means that the second electrical signal varies with the current output from the battery. The second electrical signal may be a continuous signal, for example may be a voltage signal; the second electrical signal may also be a discrete signal, for example, a level signal. Whether the second electrical signal is a continuous signal or a discrete signal depends on the specific circuit design of the current module 32. When the first electric signal is a discrete signal, a low level signal can be used for indicating large current, and a high level signal can be used for indicating small current; it is also possible to indicate a small current with a high signal and a large current with a high signal. The specific level signal used to represent the specific current signal depends on the specific circuit design of the temperature module 31.

The battery control module 33 may be any circuit module capable of controlling the battery to normally output when the ambient temperature is abnormal and the current is smaller than the preset current threshold. Specifically, the battery control module 33 may determine whether the ambient temperature is abnormal according to the first electrical signal input by the temperature module 31, and determine whether the current output by the battery is greater than a preset current threshold according to the second electrical signal input by the current module 32; and then controlling whether the battery outputs according to the judged result.

Because the temperature module can export the first signal of telecommunication that corresponds with ambient temperature, the second signal of telecommunication that the current module can export and the electric current corresponds for battery control module can judge whether ambient temperature is greater than first preset temperature or whether be less than the second preset temperature and judge whether the electric current is less than and predetermine the current threshold value and then control the battery and normally export when ambient temperature is greater than first preset temperature and the electric current is less than and predetermine the current threshold value according to the first signal of telecommunication, consequently, the utility model discloses a battery protection circuit also can maintain the undercurrent power supply of battery when ambient temperature is unusual (be high temperature or low temperature promptly), thereby can let equipment keep normal use.

Optionally, the battery control module 33 is further configured to control the battery to stop outputting when it is determined that the ambient temperature is abnormal according to the first electrical signal and it is determined that the current is greater than a preset current threshold according to the second electrical signal; and/or the battery control module 33 is further configured to control the battery 10 to normally output when it is determined that the ambient temperature is normal according to the first electrical signal, where the ambient temperature is normal, and the ambient temperature is greater than or equal to the second preset temperature and is less than or equal to the first preset temperature. Through carrying out different control to the battery under different circumstances, can let the battery work rationally, prevent that the battery from damaging.

The specific circuit design and operation principle of each module in the battery protection circuit 30 described above will be described in detail below with reference to fig. 3 to 10.

In one possible design, as shown in fig. 3, the temperature module 31 may include a temperature acquisition unit 311 and a temperature determination unit 312; the temperature acquisition unit 311 includes a temperature acquisition component, and the temperature acquisition unit 311 is connected to one end of the temperature determination unit 312 and is configured to acquire an ambient temperature; the other end of the temperature determining unit 312 is connected to a first input end of the battery control module 33, and is configured to determine the ambient temperature and output a first electrical signal corresponding to the ambient temperature to the battery control module.

The temperature acquisition component can be a thermistor, and the resistance value of the thermistor changes along with the change of the ambient temperature. Specifically, the temperature collecting part may be a Negative Temperature Coefficient (NTC) thermistor, the resistance of which decreases as the temperature increases.

In a specific design, as shown in fig. 4, the temperature collecting unit 311 may include an NTC thermistor Rntc1, a twelfth resistor R1 and a thirteenth resistor R2, wherein one end of the NTC thermistor Rntc1 is connected to a power supply, the other end of the NTC thermistor Rntc1 is connected to one end of the twelfth resistor R1, the other end of the twelfth resistor R1 is connected to one end of the thirteenth resistor R2 and one end of the temperature determining unit 312, and the other end of the thirteenth resistor R2 is grounded. In the circuit design, the NTC thermistor Rntc1, the twelfth resistor R1 and the thirteenth resistor R2 form a voltage division circuit, when the resistance value of the NTC thermistor Rntc1 changes along with the ambient temperature, the voltage value Vntc at the two ends of the twelfth resistor R2 also changes, so that the voltage value at the two ends of the thirteenth resistor R2 can reflect the ambient temperature to finish the collection of the ambient temperature, and the temperature judgment unit can judge the ambient temperature according to the voltage value Vntc at the two ends of the twelfth resistor R1.

Optionally, as shown in fig. 4, the temperature collecting unit 311 may further include a first capacitor C1 and a second capacitor C2, wherein one end of the first capacitor C1 is connected to the power supply and one end of the NTC thermistor Rntc1, the other end of the first capacitor C1 is grounded, and the second capacitor C2 is connected in parallel to the thirteenth resistor R2. The capacitor is arranged in the temperature acquisition unit, so that irrelevant signals can be filtered, and the acquired environmental temperature is more accurate.

In some possible designs, the temperature determining unit 312 may determine the temperature by a comparison circuit, and output the first electrical signal by a logic circuit. Specifically, as shown in fig. 5, the temperature determination unit 312 may include a first comparison circuit 312A, a second comparison circuit 312B, and a second logic circuit 312C. An input end of the first comparison circuit 312A is connected to the temperature acquisition unit 311, and an output end of the first comparison circuit 312A is connected to a first input end of the second logic circuit 312C, and is configured to determine whether the ambient temperature is higher than the first preset temperature, and output a high temperature indication signal to the second logic circuit 312C when the ambient temperature is higher than the first preset temperature; an input end of the second comparing circuit 312B is connected to the temperature acquiring unit 311, an output end of the second comparing circuit 312B is connected to a second input end of the second logic circuit 312C, and is configured to determine whether the ambient temperature is lower than a second preset temperature, and output a low temperature indication signal to the second logic circuit 312C when the ambient temperature is lower than the second preset temperature, where the second preset temperature is lower than the first preset temperature; the output end of the second logic circuit 312C is connected to the first input end of the battery control module 33, and is configured to output a first electrical signal for indicating temperature abnormality to the battery control module when receiving the high temperature indication signal or the low temperature indication signal.

In one specific design, as shown in fig. 6, the first comparison circuit 312A includes a first comparator U1, a first resistor R7, and a second resistor R8; the non-inverting input end of the first comparator U1 is connected to one end of the first resistor R7 and one end of the second resistor R8, the other end of the first resistor R7 is connected to the power supply, the other end of the second resistor R8 is grounded, the inverting input end of the first comparator U1 is connected to the temperature acquisition unit 311, and the output end V _ high of the first comparator U1 is connected to the first input end of the second logic circuit 312C. When the voltage signal Vntc is greater than the reference voltage of the non-inverting input end of the first comparator, the V _ high outputs a low-level signal 0; when the voltage signal Vntc is smaller than the reference voltage of the non-inverting input terminal of the first comparator, V _ high outputs a high level signal 1.

In one specific design, as shown in fig. 6, the second comparator circuit 312B includes a second comparator U2, a third resistor R3, and a fourth resistor R4; the non-inverting input end of the second comparator U2 is connected to the temperature acquisition unit 311, the inverting input end of the second comparator U2 is connected to one end of the third resistor R3 and one end of the fourth resistor R4, the other end of the third resistor R3 is connected to the power supply, the other end of the fourth resistor R4 is grounded, and the output end of the second comparator U2 is connected to the second input end V _ low of the second logic circuit 312C. When the voltage signal Vntc is smaller than the reference voltage of the inverting input end of the second comparator, the V _ low outputs a low level signal 0; when the voltage signal Vntc is greater than the reference voltage at the inverting input terminal of the first comparator, V _ low outputs a high level signal 1.

In one specific design, as shown in FIG. 6, the second logic 312C may be a NAND gate logic.

In some possible designs, as shown in fig. 7, the current module 32 includes a signal amplification circuit 321 and a third comparison circuit 322; one end of the signal amplification circuit 321 is connected to the battery 10, and is configured to collect current output by the battery 10 and amplify a signal; one end of the third comparing circuit 322 is connected to the other end of the signal amplifying circuit 321, and the other end of the third comparing circuit 322 is connected to the second input end of the battery control module 33, and is configured to determine whether the current is greater than the preset current threshold according to an electrical signal obtained by signal amplification, and output a second electrical signal for indicating an overcurrent when the current is greater than the preset current threshold.

In one specific design, as shown in fig. 8, the signal amplification circuit 321 includes an operational amplifier U4, a seventh resistor R9, an eighth resistor R13, a ninth resistor R12, a tenth resistor R11, and an eleventh resistor R15; one end of the seventh resistor R9 is connected to one end of the battery 10 and one end of the eighth resistor R13, the other end of the seventh resistor R9 is connected to one end of the ninth resistor R12, the other end of the ninth resistor R12 is connected to one end of the tenth resistor R11 and the inverting input terminal of the operational amplifier U4, the other end of the tenth resistor R11 is connected to the output terminal Vout of the operational amplifier U4 and one end of the third comparator 322, the other end of the eighth resistor R13 is connected to one end of the eleventh resistor R15 and the non-inverting input terminal of the operational amplifier U4, and the other end of the eleventh resistor R15 is grounded. The signal amplification factor Gain = R11/R12 of the signal amplification circuit, the voltage Vout = Iload R9 Gain + Vref at the output end of the signal discharge circuit, iload is the current output by the battery, and Vref =0 volts (V).

In one specific design, as shown in fig. 8, the third comparator circuit 322 includes a third comparator U3, a fifth resistor R5, and a sixth resistor R6; the in-phase input end of the third comparator U3 is connected to the other end of the signal amplifying circuit 321, the inverting input end of the third comparator U3 is connected to one end of the fifth resistor R5 and one end of the sixth resistor R6, the other end of the fifth resistor R5 is connected to the power supply, the other end of the sixth resistor R6 is grounded, and the output end V _ current of the third comparator U3 is connected to the second input end of the battery control module 33. When the voltage Vout of the output end of the signal amplification circuit is greater than the reference voltage of the inverting input end of the third comparator, the V _ curren outputs a high-level signal 1; when the voltage Vout of the output terminal of the signal amplification circuit is smaller than the reference voltage of the inverting input terminal of the third comparator, V _ curren outputs a low level signal 0.

Optionally, as shown in fig. 8, the current module 31 further includes a third capacitor C3, a fourth capacitor C4, and an inductor FB, wherein one end of the seventh resistor is connected to the battery 10 through the inductor FB, one end of the third capacitor C3 is connected to one ends of the battery 10 and the fourth capacitor C4, and the other end of the third capacitor C3 and the other end of the fourth capacitor C4 are grounded. And the third capacitor, the fourth capacitor and the inductor FB form a filter circuit, so that the anti-interference capability of the battery protection circuit can be improved.

In some possible designs, in the case that the first electrical signal and the second electrical signal are both level signals, the battery control module 31 may implement the judgment of the ambient temperature, the current output by the battery, and the output control of the battery through a logic circuit and a switch. Wherein the switch may be a transistor. As shown in fig. 9, the battery control module 33 may include a first logic circuit 331 and a transistor 332, a first input terminal of the first logic circuit 331 is connected to the temperature module 31, a second input terminal of the first logic circuit 331 is connected to the other terminal of the current module 32, an output terminal of the first logic circuit 331 is connected to a controlled terminal of the transistor 332, and an on-off output terminal of the transistor 332 is connected to the battery.

The first logic circuit 331 may be a gate logic circuit, such as an and gate logic circuit, an or gate logic circuit, an xor gate logic circuit, and so on. The specific type of gate logic circuit that the first logic circuit is depends on the specifics of the first electrical signal and the second electrical signal. The transistor 332 may be an electron tube capable of performing on-off control, such as a triode or a MOS tube. When the transistor is a triode, the base electrode of the triode is the controlled end of the transistor, and the collector electrode or the emitter electrode of the triode is the on-off output end of the transistor; when the transistor is an MOS transistor, the grid of the MOS transistor is the controlled end of the transistor, and the source or the drain of the MOS transistor is the on-off output end of the transistor.

In a specific design, as shown in fig. 10, the first logic circuit 331 may be an and logic circuit, and the transistor may be a PMOS transistor Q1, where a first input terminal of the and logic circuit 331 is connected to the output terminal of the temperature module 31, a second input terminal of the and logic circuit 331 is connected to the output terminal of the current module 32, an output terminal VBAT _ EN of the and logic circuit 331 is connected to a gate of the PMOS transistor Q1, a source of the PMOS transistor Q1 is connected to the battery, and a drain of the PMOS transistor Q1 is connected to the power supply.

Optionally, as shown in fig. 10, the battery control module 33 may further include a fifth capacitor C5 and a sixth capacitor C6, where one end of the fifth capacitor C5 is connected to the source of the PMOS transistor Q1 and the battery, the other end of the fifth capacitor C5 is grounded, one end of the sixth capacitor C6 is connected to the drain of the PMOS transistor Q1 and the power supply, and the other end of the sixth capacitor C6 is grounded. The capacitor is arranged in the battery control module, so that noise signals can be filtered, and the battery control module can control the battery more stably.

Optionally, as shown in fig. 10, the battery control module 31 may further include a thirteenth resistor R16 and a fourteenth resistor R14, where the and gate logic circuit 331 is grounded through the thirteenth resistor R16, and the and gate logic circuit 331 is connected to the gate of the PMOS transistor Q1 through the fourteenth resistor R14.

The specific circuit structure of each module is different, and the operation principle of each module is different. The operation principle of the battery protection operating circuit of the present application will be described below with the circuit configuration of the temperature module 31 including the circuit configurations shown in fig. 4 and 6, the circuit configuration of the current module 32 being the circuit configuration shown in fig. 8, and the circuit configuration of the battery control module 31 being the circuit configuration shown in fig. 10:

in the first case: when the environment temperature is lower than a second preset temperature and the current output by the battery is smaller than a preset current threshold value, the resistance value of Rntc1 is larger, vntc is smaller than the reference voltage of the non-inverting input end of U1, V _ high outputs a high-level signal 1, vntc is smaller than the reference voltage of the inverting input end of U2, V _ low outputs a low-level signal 0, and V _ temp outputs a high-level signal 1; vout is less than the reference voltage of the inverting input end of U3, and V _ current outputs a low level signal 0; VBAT _ EN outputs a low level signal 0, Q1 is conducted, and the battery normally outputs.

In the second case: when the environment temperature is higher than a first preset temperature and the current output by the battery is smaller than a preset current threshold value, the resistance value of Rntc1 is smaller, vntc is larger than the reference voltage of the non-inverting input end of U1, V _ high outputs a high level signal 0, vntc is larger than the reference voltage of the inverting input end of U2, V _ low outputs a low level signal 1, and V _tempoutputs a high level signal 1; vout is smaller than the reference voltage of the inverting input end of U3, and V _ current outputs a low-level signal 0; VBAT _ EN outputs a low level signal 0, Q1 is conducted, and the battery normally outputs.

In the third case: when the environment temperature is lower than a second preset temperature and the current output by the battery is larger than a preset current threshold value, the resistance value of Rntc1 is larger, vntc is smaller than the reference voltage of the non-inverting input end of U1, V _ high outputs a high level signal 1, vntc is smaller than the reference voltage of the inverting input end of U2, the output end V _ low of U2 outputs a low level signal 0, and V _tempoutputs a high level signal 1; vout is larger than the reference voltage of the inverting input end of U3, and V _ current outputs a low-level signal 1; VBAT _ EN outputs a high level signal 1, Q1 is turned off, and the battery stops outputting.

In a fourth case: when the environment temperature is higher than a first preset temperature and the current output by the battery is higher than a preset current threshold value, the resistance value of Rntc1 is larger, vntc is higher than the reference voltage of the non-inverting input end of U1, V _ high outputs a high level signal 0, vntc is higher than the reference voltage of the inverting input end of U2, the output end V _ low of U2 outputs a low level signal 1, and V _tempoutputs a high level signal 1; vout is larger than the reference voltage of the inverting input end of U3, and V _ current outputs a low-level signal 1; VBAT _ EN outputs a high level signal 1, Q1 is turned off, and the battery stops outputting.

In the fifth case: when the environment temperature is greater than or equal to a second preset temperature and less than or equal to a first preset temperature, the resistance value of Rntc1 is within a preset interval, vntc is less than the reference voltage of the non-inverting input end of U1, V _ high outputs a high-level signal 1, vntc is greater than the reference voltage of the inverting input end of U2, V _ low outputs a low-level signal 1, and V _ temp outputs a high-level signal 0; VBAT _ EN outputs low level signal 0, Q1 is conducted, and the battery outputs normally.

Through the circuit described above, under the condition that the ambient temperature is normal (i.e. the ambient temperature is greater than or equal to the second preset temperature and less than or equal to the first preset temperature), no matter whether the current output by the battery is a large current (i.e. greater than the preset current threshold) or a small current (i.e. less than or equal to the preset current threshold), the battery protection circuit 30 can control the battery to normally output, i.e. the battery normally supplies power; when the ambient temperature exceeds the normal range (i.e. the ambient temperature is lower than the second preset temperature or higher than the first preset temperature), the battery protection circuit 30 controls the battery to stop outputting when the current output by the battery is a large current, and controls the battery to normally output only when the current output by the battery is a small current. Normal use of the apparatus can be ensured by allowing a small current to be normally output in the case where the ambient temperature exceeds the normal range, and damage to the battery can be prevented by prohibiting a large current output. Specifically, when the circuit is applied to the intelligent door lock, the low-power module (namely, the fingerprint module, the password module and the like) of the door lock can normally work under the condition that the ambient temperature exceeds a normal range, so that the intelligent door lock can be normally used, and meanwhile, the high-power module (for example, the face recognition module and the like) of the door lock can pause to work under the condition that the ambient temperature exceeds the normal range, so that the circuit is prevented from being damaged.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the invention, which is defined by the appended claims.

Claims

1. A battery protection circuit, comprising a temperature module, a current module, a battery control module, wherein:

2. The battery protection circuit of claim 1, wherein the battery control module comprises a first logic circuit and a switch;

the first input end of the first logic circuit is connected with the temperature module, the second input end of the first logic circuit is connected with the other end of the current module, the output end of the first logic circuit is connected with the controlled end of the switch, and the on-off output end of the switch is connected with the battery.

3. The battery protection circuit of claim 1, wherein the temperature module comprises a temperature acquisition unit and a temperature determination unit;

the temperature acquisition unit is connected with one end of the temperature judgment unit and is used for acquiring the ambient temperature;

the other end of the temperature judging unit is connected with a first input end of the battery control module and used for judging the ambient temperature and outputting a first electric signal corresponding to the ambient temperature to the battery control module.

4. The battery protection circuit according to claim 3, wherein the temperature determination unit includes a first comparison circuit, a second comparison circuit, and a second logic circuit;

the input end of the first comparison circuit is connected with the temperature acquisition unit, and the output end of the first comparison circuit is connected with the first input end of the second logic circuit, so as to judge whether the ambient temperature is higher than the first preset temperature or not, and output a high-temperature indication signal to the second logic circuit when the ambient temperature is higher than the first preset temperature;

the input end of the second comparison circuit is connected with the temperature acquisition unit, the output end of the second comparison circuit is connected with the second input end of the second logic circuit, and the second comparison circuit is used for judging whether the ambient temperature is lower than a second preset temperature or not and outputting a low-temperature indication signal to the second logic circuit when the ambient temperature is lower than the second preset temperature, and the second preset temperature is lower than the first preset temperature;

the output end of the second logic circuit is connected with the first input end of the battery control module and used for outputting a first electric signal for indicating temperature abnormity to the battery control module when the high-temperature indication signal or the low-temperature indication signal is received.

5. The battery protection circuit of claim 4, wherein the first comparison circuit comprises a first comparator, a first resistor, and a second resistor;

the non-inverting input end of the first comparator is connected with one end of the first resistor and one end of the second resistor, the other end of the first resistor is connected with a power supply, the other end of the second resistor is grounded, the inverting input end of the first comparator is connected with the temperature acquisition unit, and the output end of the first comparator is connected with the first input end of the second logic circuit;

the second comparison circuit comprises a second comparator, a third resistor and a fourth resistor;

the in-phase input end of the second comparator is connected with the temperature acquisition unit, the inverting input end of the second comparator is connected with one end of the third resistor and one end of the fourth resistor, the other end of the third resistor is connected with the power supply, the other end of the fourth resistor is grounded, and the output end of the second comparator is connected with the second input end of the second logic circuit.

6. The battery protection circuit according to any one of claims 1-5, wherein the current module comprises a signal amplification circuit and a third comparison circuit;

one end of the signal amplification circuit is connected with the battery and is used for collecting the current output by the battery and amplifying a signal;

one end of the third comparison circuit is connected with the other end of the signal amplification circuit, the other end of the third comparison circuit is connected with the second input end of the battery control module, and the third comparison circuit is used for judging whether the current is greater than the preset current threshold value according to an electric signal obtained by signal amplification and outputting a second electric signal for indicating overcurrent when the current is greater than the preset current threshold value.

7. The battery protection circuit of claim 6, wherein the third comparison circuit comprises a third comparator, a fifth resistor, and a sixth resistor;

the in-phase input end of the third comparator is connected with the other end of the signal amplification circuit, the inverting input end of the third comparator is connected with one end of the fifth resistor and one end of the sixth resistor, the other end of the fifth resistor is connected with the power supply, the other end of the sixth resistor is grounded, and the output end of the third comparator is connected with the second input end of the battery control module.

8. The battery protection circuit according to claim 6, wherein the signal amplification circuit comprises an operational amplifier, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, and an eleventh resistor;

one end of the seventh resistor is connected with one end of the battery and one end of the eighth resistor, the other end of the seventh resistor is connected with one end of the ninth resistor, the other end of the ninth resistor is connected with one end of the tenth resistor and the inverting input end of the operational amplifier, the other end of the tenth resistor is connected with the output end of the operational amplifier and one end of the third comparison circuit, the other end of the eighth resistor is connected with one end of the eleventh resistor and the non-inverting input end of the operational amplifier, and the other end of the eleventh resistor is grounded.

9. The battery protection circuit of claim 1, wherein the battery control module is further configured to control the battery to stop outputting when the ambient temperature is determined to be abnormal according to the first electrical signal and the current is determined to be greater than a preset current threshold according to the second electrical signal;

and/or the presence of a gas in the atmosphere,

the battery control module is further used for controlling the battery to normally output when the ambient temperature is determined to be normal according to the first electric signal, wherein the normal ambient temperature means that the ambient temperature is greater than or equal to the second preset temperature and is less than or equal to the first preset temperature.

10. An intelligent door lock, characterized by comprising a battery, a load and a battery protection circuit according to any one of claims 1-9.

11. The intelligent door lock of claim 10, wherein the load comprises a first load and a second load, and the first load and the second load are both connected with the battery and are used for operating based on the current output by the battery, wherein the current required by the first load to operate is less than the preset current threshold value, and the current required by the second load to operate is greater than or equal to the preset current threshold value;

the battery protection circuit is used for controlling the battery to supply power to the first load and stop supplying power to the second load when the ambient temperature is abnormal.