CN107346909A

CN107346909A - A kind of charging circuit and battery

Info

Publication number: CN107346909A
Application number: CN201710341886.XA
Authority: CN
Inventors: 王钊
Original assignee: Nanjing Sino Microelectronics Co Ltd
Current assignee: Nanjing Sino Microelectronics Co Ltd
Priority date: 2017-05-12
Filing date: 2017-05-12
Publication date: 2017-11-14

Abstract

A kind of charging circuit is provided in the embodiment of the present application, including：Charge circuit, for being charged to battery core；Sensor, the sensor are located in battery, and are less than preset distance with the distance of the battery core, for sensing the temperature of the battery core；The sensor is negative temperature coefficient sensor or positive temperature coefficient sensor；Constant-current source, for for the sensors with current；Field-effect transistor, in conducting, shunting the charging current of the charge circuit；First operational amplifier OP2, when the battery core temperature for being arrived in the sensor sensing exceedes predetermined temperature Tch, control field-effect transistor conducting, predetermined temperature is maximum charge temperature set in advance, battery core.Using the scheme in the application, by preventing that battery core temperature is too high in charging process, charging security is improved.

Description

A kind of charging circuit and battery

Technical field

The application is related to IC design field, in particular it relates to a kind of charging circuit and battery.

Background technology

It is faster due to charging for electronic equipment, the time is more saved, especially for mancarried electronic aid, user Quick-charge function is generally required, and the faster equipment that charges is more welcome.Therefore, in recent years, for various quick charges Technology has carried out numerous studies.

Accelerate charging rate typically by the way of raising charging current.

But inventor has found that after raising charging current, battery core temperature turns into another limitation.That is, when charging current compared with Greatly, when and duration of charge is longer, battery core temperature can be caused to rise, if battery core temperature is too high, battery performance may be caused Decline, battery permanent damages can be caused when serious, there is also potential safety hazard.

The content of the invention

A kind of charging circuit and battery are provided in the embodiment of the present application, for solving in charging process in the prior art, The problem of security declines caused by battery core temperature is too high.

According to the one side of the embodiment of the present application, there is provided a kind of charging circuit, including：Charge circuit, for Battery core charges；Sensor, the sensor are located in battery, and are less than preset distance with the distance of the battery core, for sensing the electricity The temperature of core；The sensor is negative temperature coefficient sensor or positive temperature coefficient sensor；Constant-current source, for being carried for the sensor Power supply stream；Field-effect transistor, in conducting, shunting the charging current of the charge circuit；First operational amplifier OP2, When battery core temperature for being arrived in the sensor sensing exceedes predetermined temperature Tch, control field-effect transistor conducting, this is predetermined Temperature is maximum charge temperature set in advance, battery core.

According to the second of the embodiment of the present application aspect, a kind of battery is additionally provided, including：Battery core, and described above Charging circuit.

Using the charging circuit and battery provided in the embodiment of the present application, pass through positive temperature coefficient or the biography of negative temperature coefficient Sensor senses the temperature of battery core, when detecting that battery core temperature is too high, turns on field-effect transistor, the charging to charge circuit Electric current is shunted, and reduces the charging current of battery core, to reduce the temperature of battery core, so as to form the negative-feedback of battery core temperature electricity Road, when stablizing, control battery core temperature is maintained at design temperature charging, prevents that battery core temperature is too high, improves the peace of charging Quan Xing.

Brief description of the drawings

Accompanying drawing described herein is used for providing further understanding of the present application, forms the part of the application, this Shen Schematic description and description please is used to explain the application, does not form the improper restriction to the application.In the accompanying drawings：

Fig. 1 shows the circuit diagram of the charging circuit according to the embodiment of the present application one.

Embodiment

During the application is realized, inventor find, in the prior art, by the way of raising charging current come When accelerating charging rate, after the charging interval continues for some time, battery core temperature can be caused to rise, if battery core temperature is too high, Battery performance may be caused to decline, battery permanent damages can be caused when serious, while will also result in potential safety hazard.

To solve the above problems, this application provides a kind of charging circuit and battery, pass through positive temperature coefficient or negative temperature The sensor of coefficient senses the temperature of battery core, when sensor detects that battery core temperature is too high, turns on field-effect transistor, right The charging current of charge circuit is shunted, and reduces the charging current of battery core, to reduce the temperature of battery core, so as to form battery core temperature The negative-feedback circuit of degree, when stablizing, control battery core temperature is maintained at design temperature charging, prevents that battery core temperature is too high, carries The high security of charging.

In order that the technical scheme and advantage in the embodiment of the present application are more clearly understood, below in conjunction with accompanying drawing to the application Exemplary embodiment be described in more detail, it is clear that described embodiment be only the application a part implementation Example, rather than the exhaustion of all embodiments.It should be noted that in the case where not conflicting, embodiment and reality in the application Applying the feature in example can be mutually combined.

Embodiment one

As shown in circuit in Fig. 1 dotted line frames, according to the charging circuit of the embodiment of the present application one, including：

Charge circuit, the charge circuit include the second PMOS NMOS tube MN1 of MPA, the 3rd PMOS MPB, first, resistance R3, the second operational amplifier OP1；

Sensor, the sensor are located in battery, and are less than preset distance with battery core BAT distance, for sensing the electricity The temperature of core；

Current source, for providing electric current for thermo-sensitive resistor Rntc；

First PMOS MPC, in conducting, shunting the charging current of the charge circuit；

First operational amplifier OP2, when the battery core temperature for being arrived in sensor sensing exceedes predetermined temperature Tch, control First PMOS turns on, and the predetermined temperature is maximum charge temperature set in advance, battery core.

In the specific implementation, can be encapsulated according to the charging circuit of the embodiment of the present application in same chip.

In the specific implementation, sensor can use the thermo-sensitive resistor Rntc of negative temperature coefficient, i.e. resistance Rntc electricity Pressure difference rises and declined with temperature.

In the specific implementation, the distance between thermo-sensitive resistor and battery core can be less than 5 millimeters of distance, and the application is to this It is not restricted.Because the distance of sensor and battery core is close, due to the effect of heat transfer, both temperature are very close, can be with Think approximately the same.

In the specific implementation, the battery core maximum charge temperature of setting can be according to the material of battery core, environmental factor etc. really Fixed safe charging temperature, such as 45 degrees Celsius, 50 degrees Celsius etc., the application is not restricted to this.

In the specific implementation, current source I1 can be constant-current source that is accurate and not changed by temperature change.

In the specific implementation, first PMOS MPC can also realize that the application is not limited this using NMOS tube System.

The specific annexation of above-mentioned each part is as follows：

First operational amplifier OP2 positive input terminates one end of the sensor；Negative input terminates the first reference voltage VR2；The sensor other end is grounded；PMOS MPC grid connects the first operational amplifier OP2 output end, and source electrode connects power supply VDD。

In charge circuit, the second PMOS MPA drain electrode connects battery core BAT positive pole, and second PMOS MPA grid connects 3rd MPOS pipes MPB grid；The drain electrode of 3rd PMOS connects first NMOS tube MN1 drain electrode, the 3rd PMOS The drain electrode of grid and the 3rd PMOS connect；The grid of first NMOS tube connects second operational amplifier OP1 output End, the source electrode of first NMOS tube meet resistance R3；The positive input of second operational amplifier terminates the second reference voltage VR1, Negative input terminates the source electrode of first NMOS tube, and output terminates the grid of second PMOS；A resistance R3 termination this The source electrode of one NMOS tube, the other end are grounded after being connected to the negative pole of the battery core；The drain electrode of second PMOS connect this first The source electrode of NMOS tube；The drain electrode of first PMOS connects the source electrode of first NMOS tube.

In the specific implementation, the sensor can also be the thermo-sensitive resistor of positive temperature coefficient.Now, the second operational amplifier Positive input termination reference voltage VR2, negative input termination thermo-sensitive resistor.

In the specific implementation, reference voltage VR2 and VR1 can use band-gap reference circuit common in the art to produce It is raw, in order to simplify description, description is omitted herein.

In the specific implementation, the resistance value of the sensor meets following condition：When the temperature of the thermo-sensitive resistor reaches predetermined During temperature Tch, the size of the resistance value Rntc (Tch) of the sensor and electric current I1 of current source product is equal to first ginseng Voltage VR2 is examined, wherein, the predetermined temperature is maximum charge temperature set in advance, the battery core.

Specifically, when battery core BAT temperature is relatively low, resistance Rntc resistance is higher, and current source flows through resistance Rntc generations Voltage VRt be more than VR2, now operational amplifier OP2 output signals GMPC voltages are high level, equal to supply voltage, so as to So that first PMOS | Vgs | be less than | Vthp |, PMOS MPC is in cut-off state, so as to the charge circuit not influenceed Charging.

The operation principle of charge circuit is as follows：Operational amplifier OP1 forms feedback loop with NMOS tube MN1, resistance R3, Operational amplifier adjusts the voltage for causing V3 voltages to be equal to VR1, and now resistance R3 electric current is equal to VR1/R3, and wherein VR1 is ginseng Voltage VR1 magnitude of voltage is examined, R3 is resistance R3 resistance value.According to Kirchhoff's law, resistance R3 current value is equal to NMOS Pipe MN1 drain current value, PMOS MPB drain current value being also equal to, PMOS MPA and PMOS MPB forms current mirror, Replica current, such as the ratio between MPA breadth length ratio and MPB breadth length ratio are N: 1, then drain electrode electricity of the MPA drain current equal to MPB N times of stream.Therefore MPA is multiplied in the first reference voltage VR1 again divided by the constant current of resistance R3 resistance enters to battery core BAT with N Row charging.

In the specific implementation, when the terminal voltage VRt of the thermo-sensitive resistor raises with the temperature of the battery core so that first computing The output voltage of amplifier reduces so that | Vgs | be more than | Vthp | when, first operational amplifier controls first PMOS MPC is turned on, and the first MPOS pipes shunt the drain current of first NMOS tube so that the charging current drop of first charge circuit It is low.

Specifically, when battery core maximum charge temperature of the battery core temperature close to setting, Rntc resistance reduces than before, leads When causing VRt voltage to be near or below VR2 voltages, GMPC voltages decline, | Vgs | be more than | Vthp | when, PMOS MPC is led It is logical, shunt MN1 drain current so that MN1 drain current reduces, i.e. MPB drain current also reduces, MPA drain electrode electricity Stream also reduces therewith, so forms negative-feedback circuit, will be adjusted when this negative-feedback circuit is stable so that VRt voltage is equal to VR2 Voltage, now the temperature of battery core be equal to the battery core maximum charge temperature of setting, such as 45 degrees Celsius.

Using the charging circuit in the embodiment of the present application, sensed by the sensor of positive temperature coefficient or negative temperature coefficient The temperature of battery core, when sensor detects that battery core temperature is too high, the first PMOS MPC is turned on, the charging electricity to charge circuit Stream is shunted, and reduces the charging current of battery core, to reduce the temperature of battery core, so as to form the negative-feedback circuit of battery core temperature, When stablizing, control battery core temperature is maintained at design temperature charging, prevents that battery core temperature is too high, improves the safety of charging Property.

In addition, using the charging circuit in the embodiment of the present application, cause battery core adstante febre in lasting charging, can charge It is balanced between temperature and charging current, maintains battery to carry out maximum current charging under the allowed maximum temperature that charges, Charge efficiency is high.

Embodiment two

Based on same inventive concept, a kind of battery is additionally provided in the embodiment of the present application.

Included according to the battery of the embodiment of the present application two：Battery core BAT, and the charging electricity according to the embodiment of the present application one Road.

The specific implementation of the charging circuit in battery in the embodiment of the present application is referred in the embodiment of the present application one The implementation of charging circuit, repeat part and repeat no more.

Using the battery in the embodiment of the present application, battery core is sensed by the sensor of positive temperature coefficient or negative temperature coefficient Temperature, when sensor detects that battery core temperature is too high, turn on the first PMOS MPC, the charging current of charge circuit is entered Row shunting, the charging current of battery core is reduced, to reduce the temperature of battery core, so as to form the negative-feedback circuit of battery core temperature, when steady Regularly, control battery core temperature is maintained at design temperature charging, prevents that battery core temperature is too high, improve the security of charging.

In addition, using the battery in the embodiment of the present application, cause battery core adstante febre in lasting charging, can be in charging temperature It is balanced between charging current, maintains battery to carry out maximum current charging, charging under the allowed maximum temperature that charges Efficiency high.

It should be understood by those skilled in the art that, embodiments herein can be provided as method, system or computer program Product.Therefore, the application can use the reality in terms of complete hardware embodiment, complete software embodiment or combination software and hardware Apply the form of example.Moreover, the application can use the computer for wherein including computer usable program code in one or more The computer program production that usable storage medium is implemented on (including but is not limited to magnetic disk storage, CD-ROM, optical memory etc.) The form of product.

The application is with reference to the flow according to the method for the embodiment of the present application, equipment (system) and computer program product Figure and/or block diagram describe.It should be understood that can be by every first-class in computer program instructions implementation process figure and/or block diagram Journey and/or the flow in square frame and flow chart and/or block diagram and/or the combination of square frame.These computer programs can be provided The processors of all-purpose computer, special-purpose computer, Embedded Processor or other programmable data processing devices is instructed to produce A raw machine so that produced by the instruction of computer or the computing device of other programmable data processing devices for real The device for the function of being specified in present one flow of flow chart or one square frame of multiple flows and/or block diagram or multiple square frames.

These computer program instructions, which may be alternatively stored in, can guide computer or other programmable data processing devices with spy Determine in the computer-readable memory that mode works so that the instruction being stored in the computer-readable memory, which produces, to be included referring to Make the manufacture of device, the command device realize in one flow of flow chart or multiple flows and/or one square frame of block diagram or The function of being specified in multiple square frames.

These computer program instructions can be also loaded into computer or other programmable data processing devices so that counted Series of operation steps is performed on calculation machine or other programmable devices to produce computer implemented processing, so as in computer or The instruction performed on other programmable devices is provided for realizing in one flow of flow chart or multiple flows and/or block diagram one The step of function of being specified in individual square frame or multiple square frames.

Although having been described for the preferred embodiment of the application, those skilled in the art once know basic creation Property concept, then can make other change and modification to these embodiments.So appended claims be intended to be construed to include it is excellent Select embodiment and fall into having altered and changing for the application scope.

Obviously, those skilled in the art can carry out the essence of various changes and modification without departing from the application to the application God and scope.So, if these modifications and variations of the application belong to the scope of the application claim and its equivalent technologies Within, then the application is also intended to comprising including these changes and modification.

Claims

A kind of 1. charging circuit, it is characterised in that including：

Charge circuit, for being charged to battery core；

Sensor, the sensor are located in battery, and are less than preset distance with the distance of the battery core, for sensing the electricity The temperature of core；The sensor is negative temperature coefficient sensor or positive temperature coefficient sensor；

Current source, for for the sensors with current；

Field-effect transistor, in conducting, shunting the charging current of the charge circuit；

First operational amplifier OP2, when the battery core temperature for being arrived in the sensor sensing exceedes predetermined temperature Tch, control The field-effect transistor conducting, the predetermined temperature are the maximum charge temperature of set in advance, described battery core.
2. circuit according to claim 1, it is characterised in that the field-effect transistor is the first PMOS or second NMOS tube.
3. circuit according to claim 2, it is characterised in that the charge circuit includes：

The second PMOS NMOS tube MN1 of MPA, the 3rd PMOS MPB, first, resistance R3, the second operational amplifier OP1；

Wherein, the drain electrode of second PMOS connects the positive pole of the battery core, and the grid of second PMOS connects the described 3rd The grid of MPOS pipes；The drain electrode of 3rd PMOS connects the drain electrode of first NMOS tube, the grid of the 3rd PMOS Drain electrode with the 3rd PMOS connects；The grid of first NMOS tube connects the output end of second operational amplifier, The source electrode of first NMOS tube meets the resistance R3；The positive input of second operational amplifier terminates the second reference voltage VR1, negative input terminate the source electrode of first NMOS tube, and output terminates the grid of second PMOS；The resistance R3's The source electrode of one termination first NMOS tube, the other end are grounded after being connected to the negative pole of the battery core；Second PMOS Drain electrode connect the source electrode of first NMOS tube.
4. circuit according to claim 3, it is characterised in that the sensor is thermo-sensitive resistor, first field-effect Transistor is the first PMOS, and the power supply source is constant-current source；

The first input end of first operational amplifier connects one end of the thermo-sensitive resistor, and the second input termination first is with reference to electricity VR2 is pressed, output end is connected with the grid of first field-effect transistor；

The of described thermo-sensitive resistor one end ground connection, the output end of the other end and the current source and first operational amplifier One input connects；

The input termination power vd D of the constant-current source, output terminate the thermo-sensitive resistor；

The grid of first PMOS connects the output end of the first operational amplifier, and source electrode meets power vd D；Drain electrode connects described first The source electrode of NMOS tube.
5. circuit according to claim 1, it is characterised in that the sensor be negative temperature coefficient thermo-sensitive resistor, institute The first input end for stating the second operational amplifier is positive input terminal, and the second input is negative input end.
6. circuit according to claim 5, it is characterised in that the resistance value Rntc of the sensor meets following condition： When the temperature of the thermo-sensitive resistor reaches the predetermined temperature Tch, resistance value Rntc (Tch) and the electricity of the sensor The size of the electric current I1 in stream source product is equal to the first reference voltage VR2.
7. circuit according to claim 6, it is characterised in that

When the output voltage of first operational amplifier causes first PMOS | Vgs | be less than | Vthp | when, it is described First PMOS MPC ends；

Wherein, it is described | Vgs | it is the absolute value of the gate source voltage of first PMOS, | Vthp | it is first PMOS The absolute value of MPC threshold voltage.
8. circuit according to claim 6, it is characterised in that the charge circuit is filled with scheduled current to the battery core Electricity.
9. circuit according to claim 8, it is characterised in that the size of the scheduled current multiplies in the first reference equal to N Voltage VR1 again divided by resistance R3 resistance, wherein, N is the width of breadth length ratio and the 3rd PMOS of second PMOS Ratio between long ratio.
10. circuit according to claim 7, it is characterised in that

When the thermo-sensitive resistor terminal voltage VRt with the battery core temperature raise so that first operational amplifier it is defeated Go out voltage reduction so that | Vgs | be more than | Vthp | when, first operational amplifier controls the first PMOS MPC conductings, The first MPOS pipes shunt the drain current of first NMOS tube so that the charging current drop of first charge circuit It is low.
A kind of 11. battery, it is characterised in that including：

Battery core；And

Such as the charging circuit any one of claim 1-10.