Invention content
It is above-mentioned of the existing technology to solve present invention aims at a kind of small battery charging method of proposition and its deviceBaby battery charging equipment is not fully filled the technical problem of electricity.
For this purpose, the present invention proposes a kind of small battery charging method, the first charge step：Power input unit passes through charging valveIt is charging output unit charging to manage unit；When charging, the charging current of the Charge Management unit output is detected, when the chargingWhen electric current reaches predetermined threshold value, the Charge Management unit stops charging, and generates control signal；
Second charge step：TCU transfer control unit starts voltage regulation unit according to the control signal, the power inputUnit is charged by the voltage regulation unit for the charging output unit；When charging, controlled by TCU transfer control unit described steadyUnit is pressed to stop charging.
Preferably, in second charge step：The TCU transfer control unit is by voltage stabilizing start unit by voltage regulation unitStart, and detect the charging voltage of the charging output unit by voltage detection unit, when the charging voltage reaches defaultWhen threshold value, according to the effect of the voltage detection unit, the voltage regulation unit is set to stop charging by turning off control unit.
Preferably, first charge step includes：When the charging voltage of charging output unit is not more than first voltage thresholdWhen value, the Charge Management unit is trickle charge；When the charging voltage for the output unit that charges is not less than first voltage threshold value,The Charge Management unit is constant-current charge；It is described to fill when the charging voltage for the output unit that charges is close to constant-voltage charge voltageElectric administrative unit is constant-voltage charge.
Preferably, further include the indicative step of working condition for the low current charge method；By describedTCU transfer control unit controls indicating unit work.
Preferably, first charge step with second charge step being isolated to complete by voltage isolated locationLogic control to the charging output unit voltage.
In addition, the invention also provides a kind of baby battery charging unit, including power input unit and charging output unit,With for charging output unit the Charge Management unit and voltage regulation unit that charge, and in charging process intoThe TCU transfer control unit of row conversion and control；The power input unit and the Charge Management unit and the voltage regulation unit phaseEven；The Charge Management unit includes input, output end and control terminal；The input terminal accesses the power input unit,The output end is picked out to the charging output unit；The TCU transfer control unit includes control signal input, control outputEnd, power control terminal and control feedback end, the control signal input are mutually accessed with the control terminal, the control output endConnect with the voltage regulation unit, the control feedback end connects with the charging output unit, the power control terminal with it is describedPower input unit connects.
Preferably, the TCU transfer control unit includes voltage stabilizing start unit, shutdown control unit and voltage detection unit；InstituteVoltage stabilizing start unit is stated with the control signal input and the power input to connect, and with the shutdown control unit phaseEven；The voltage detection unit connects with the control feedback end, and is connect with the shutdown control unit；The shutdown controlEnd connects with the control output end.
Preferably, further include the indicating unit for being used to indicate charged state, controlled and indicated by the TCU transfer control unitUnit carries out instruction work.
Preferably, further include at the charging output unit to the Charge Management unit and the voltage regulation unitThe voltage isolated location being isolated.
The Charge Management unit includes the first charhing unit for trickle charge, and second for constant-current charge is filledElectric unit, and the third charhing unit for constant-voltage charge.
The beneficial effect of the present invention compared with the prior art includes：The charging method and charging unit of the present invention, including theOne charge step and the second charge step, the first charge step are charged by Charge Management unit, are detecting charging electricityWhen stream reaches predetermined threshold value, the Charge Management unit stops charging, generates control signal, and then, TCU transfer control unit is by rootIt switching into the second charge step and charges according to control signal, TCU transfer control unit starts voltage regulation unit and charges, andIt controls voltage regulation unit and stops charging；It, can be to small in the first charging stage for this charging method compares existing charging methodBattery carries out basic charging, and when Charge Management unit since charging current is smaller, and when stopping charging, Charge Management unit willContinue to generate control signal, it is that baby battery equipment continues to fill which, which will start TCU transfer control unit and start voltage regulation unit,Electricity in charging process, passes through TCU transfer control unit and controls voltage regulation unit and stop charging.
Low current charge equipment can be filled to by 4.2V by battery, be made up by above-mentioned charging method and charging unitThe case where battery can not be filled to 4.2v by normal charge managing chip, realizing low current can also charge, to improveThe service efficiency of baby battery overcomes since baby battery equipment self-capacity is with regard to small, and is not fully filled the problem of electricity.
Specific implementation mode
With reference to embodiment and compares attached drawing invention is further described in detail.It is emphasized thatFollowing the description is only exemplary, the range being not intended to be limiting of the invention and its application.
With reference to the following drawings, non-limiting and nonexcludability embodiment will be described, wherein identical reference numeral indicatesIdentical component, unless stated otherwise.
As shown in Figure 1, present embodiments provide a kind of baby battery charging unit, including power input unit 1 and charge defeatedGo out unit 5, and the Charge Management unit 2 for charging to the charging output unit 5 and voltage regulation unit 3, and is used forThe TCU transfer control unit 4 of conversion and control is carried out in charging process；The power input unit 1 and the Charge Management unit 2 andThe voltage regulation unit 3 is connected；The Charge Management unit 2 includes input terminal 21, output end 22 and control terminal；The input terminalThe 21 access power input units 1, the output end 22 are picked out to the charging output unit 5；The TCU transfer control unit 4Including control signal input 41, control output end 43, power control terminal 42 and control feedback end 44, the control signal inputEnd 41 is mutually accessed with the control terminal, and the control output end 43 connects with the voltage regulation unit 3, the control feedback end 44 andThe charging output unit 5 connects, and the power control terminal 42 is connect with the power input unit 1.
As shown in Figures 2 and 3, wherein the Charge Management unit 2 of the present embodiment is PWM voltage-dropping type lithium battery Charge Management coresPiece has constant current constant voltage charging mode, and the structure of the charging management chip is the prior art, and the present invention repeats no more；Correspondingly,The Charge Management unit 2 can also be other charging management chips with constant current constant voltage charging mode.
The Charge Management unit 2 includes the first charhing unit for trickle charge, and for the second of constant-current chargeCharhing unit, and the third charhing unit for constant-voltage charge.
As shown in figure 3, the schematic diagram of the Charge Management unit 2 of the present embodiment, the Charge Management unit 2 is illustrated in conjunction with attached drawingOperation principle, wherein should know, each parameter such as charging voltage as described below, electric current etc. is only signal, is notCorresponding to the relevant parameter of the present embodiment charging output unit 5：
Constant-current charge electric current is arranged by the current sense resistor RCS being connected between CSP pins and BAT pins, in constant pressureCharge mode, cell voltage 16.8V, precision 1%.Threshold value is latched when VCC pin voltages are more than low pressure, and is more than batteryWhen voltage, charger normal work charges to battery.
If cell voltage is less than 11.2V, charger is set automatically into trickle charge pattern, at this time charging currentConstant-current charge electric current 15%.When cell voltage is more than 11.2V, charger enters constant current charging mode, at this time charging currentBy internal 200mV reference voltages and a non-essential resistance RCS setting, i.e. charging current is 200mV/RCS.When cell voltage afterWhen continuous rising is close to constant-voltage charge voltage, charger enters constant-voltage charge pattern, and charging current is gradually reduced.When charging current subtractsWhen the small value being arranged to EOC pin resistance, charging terminates, and DRV pins export high level.Crystalline substance inside open-drain output pinBody pipe turns off, and exports as high-impedance state；Transistor inside another open-drain output pin is connected, and low level is exported, to refer toShow charging end state.
In the present embodiment, charging current is by following setting：
Wherein, constant-current charge electric current is determined by following formula：
Wherein：
ICHIt is constant-current charge electric current.
RCSIt is the charging current detection resistance being connected between CSP pins and BAT pins.
Then, the setting of charging end current：
In constant-voltage charge pattern, charging current is gradually reduced, when charging current is reduced to set by the resistance of EOC pinsWhen electric current, charging terminates.
Charging end current is determined by following formula：
Wherein：
IEOCCharging end current, unit are ampere.
Rext be from EOC pin to ground between the resistance that connects, unit is ohm.The resistance value of Rext cannot be more than 100KΩ, otherwise charging will be unable to normal termination.
RCSIt is the charging current detection resistance between CSP pins and BAT pins, unit is ohm.
The ratio of charging end current and constant-current charge electric current can be calculated according to formula above：
As Rext=0, IEOC/ICH=9.17%, i.e., the minimum charging end current that user can be arranged is set perseveranceThe 9.17% of current charge electric current.
As Rext=100K Ω, IEOC/ICH=73%, i.e., the maximum charge ending current that user can be arranged is setConstant-current charge electric current 73%.
According to above-mentioned principle, the exhausted only electric current of most of lithium battery charging chip, is usually both greater than currently on the market20MA is unable to smaller, some even biggers；
That is, for baby battery equipment, even if being arranged to 9.17%, when can not meet baby battery and commonly chargingCharging terminates the minimum current value that reach, so the present embodiment when charging to baby battery, is divided into two charging stepsSuddenly, following methods are specifically shown in：
A kind of small battery charging method provided in this embodiment, charges to baby battery using above-mentioned charging unit,Including：First charge step：Power input unit 1 is that charging output unit 5 charges by Charge Management unit 2；When charging,The charging current that the Charge Management unit 2 exports is detected, when the charging current reaches predetermined threshold value, the Charge ManagementUnit 2 stops charging, and generates control signal；
Second charge step：TCU transfer control unit 4 starts voltage regulation unit 3 according to the control signal, and the power supply is defeatedEnter unit 1 to charge for the charging output unit 5 by the voltage regulation unit 3；When charging, controlled by TCU transfer control unit 4The voltage regulation unit 3 stops charging.
First charge step includes：When the charging voltage for the output unit 5 that charges is not more than first voltage threshold value, instituteIt is trickle charge to state Charge Management unit 2；It is described when the charging voltage for the output unit 5 that charges is not less than first voltage threshold valueCharge Management unit 2 is constant-current charge；When the charging voltage for the output unit 5 that charges is close to constant-voltage charge voltage, the chargingAdministrative unit 2 is constant-voltage charge.
When connecting external power supply, the first charge step is carried out, Charge Management unit 2 fills power output unitElectricity, at this point, the control terminal of Charge Management unit 2 is high-impedance state, at this point, TCU transfer control unit 4 does not work, voltage regulation unit 3 is not yetWork, voltage regulation unit 3 are exported without charging voltage；
When charging current close to 9.17% (value can be configured according to the tissue of detection resistance, such as 73%, for smallFor battery, preferably 9.17%) when, Charge Management unit 2 without charging voltage export, at this point, the control of Charge Management unit 2End is low level (control signal).
As shown in Figure 2 and Figure 4, in the present embodiment, the TCU transfer control unit 4 includes voltage stabilizing start unit 45, shutdown controlUnit 46 and voltage detection unit 47 processed；The voltage stabilizing start unit 45 and the control signal input 41 and the power supply are defeatedEnter end to connect, and is connected with the shutdown control unit 46；The voltage detection unit 47 connects with the control feedback end 44,And it is connect with the shutdown control unit 46；The shutdown control terminal connects with the control output end 43.
Voltage stabilizing start unit 45 is connected under low level effect, passes through voltage stabilizing start unit 45 by power input unit 1Power control terminal 42 input, through shutdown control unit 46 43 output signal of control output end so that voltage regulation unit 3 obtainsEnabling signal (high level), voltage regulation unit 3 are started to work, and have charging voltage output.
After regulated power supply starts, it can continue to carry out voltage stabilizing charging to charging output unit 5 (baby battery), as shown in figure 5,Regulated power supply can be voltage-stablizer, such as DC-DC, LDO etc., it can be achieved that voltage stabilizing charge, the present embodiment to voltage regulation unit 3 notIt is limited, those skilled in the art can select the voltage regulation unit 3 of setting unlike signal according to actual conditions.
Voltage regulation unit 3 continues to charge to baby battery, in charging process, passes through the voltage detecting list set on control feedback end 44The charging voltage of the charging output unit 5 of 47 pairs of charging output units 5 of member is detected, to determine that the charging of voltage regulation unit 3 terminatesTime point, voltage detection unit 47 is after charging, when detecting that voltage meets 4.2V, voltage detection unit 47 be connected,To control the signal output that connected shutdown control unit 46 cuts off control output end 43, to realize what voltage regulation unit 3 chargedTerminate.
By above-mentioned control method, low current may be implemented and overcome the problems, such as that existing charhing unit is not fully filled electricity, avoid leadingIt causes existing charhing unit baby battery to be also not up to 4.2V (often 4.0 or 4.1V or so), just terminates to charge, be controlled by convertingThe logic control of unit 4 processed is detected in conjunction with the feedback of TCU transfer control unit 4, and one can be achieved on the conversion of two charge steps,But charging can be also realized in the case of low current.
As shown in figure 4, in the present embodiment, baby battery charging unit further includes the indicating unit for being used to indicate charged state48, indicating unit 48 is controlled by the TCU transfer control unit 4 and carries out instruction work.
In the present embodiment, voltage stabilizing start unit 45 is triode, can be NPN type or positive-negative-positive, and shutdown control unit 46 isRelay, including switch K1, and it is controlled by the control unit of voltage detection unit 47, voltage detection unit 47 includes one or three polesPipe can be equally NPN type or positive-negative-positive, further include voltage-stabiliser tube, and indicating unit 48 includes LED1 and LED2, wherein voltage stabilizing startsThe triode of unit 45 and the triode of voltage detection unit 47 are different types of.
When the triode of voltage detection unit 47 stops absolutely, supply voltage is added to by K1 coils on LED1 anodes, LED1It shines, indicates charged state；According to above-mentioned principle, when battery is charged to 4.2V, when voltage detection unit 47 is connected, then voltageThe current collection of the triode of detection unit 47 extremely low level, extinguishes from LED1, and LED2 is lighted, and indicates that charging terminates；From inLED1, LED2 complete charged state instruction and charging complete indicates function.
As shown in fig. 6, in the present embodiment, baby battery charging unit further includes at the charging output unit 5 pairThe voltage isolated location 51 that the Charge Management unit 2 and the voltage regulation unit 3 are isolated.The voltage isolated location 51 includesThe diode (A1) being arranged on the output end 22 of Charge Management unit 2 and setting are in 3 output end of voltage regulation unit (i.e. control feedbackThe diode (A2) on 44) is held, is achieved in when Charge Management unit 2 charges to charging output unit 5, output voltageVoltage regulation unit 3 or TCU transfer control unit 4 will not be interfered, similarly, when voltage regulation unit 3 charges, the output of voltage regulation unit 3Voltage will not interfere Charge Management unit 2 and TCU transfer control unit 4.
Voltage detection unit 47 is when the charging voltage to the output unit 5 that charges is detected feedback, in the present embodimentIn some alternative embodiments, when voltage isolated location 51 is not arranged, voltage is detected as Vz1 (voltage stabilizing tube voltage)+Vce (collectionEmitter voltage)=Vbat (cell voltage)=4.2V, the output voltage of voltage regulation unit 3 is 4.2V at this time, when setting voltage is isolatedWhen unit 51, voltage is detected as Vd5 (isolated location voltage)+Vz1+Vce=Vbat (cell voltage)=4.2V, at this time voltage stabilizingThe output voltage of unit 3 is 4.2V, Vz1+Vce=Vbat (cell voltage)=4.2V, the at this time output voltage of voltage regulation unit 3For 4.9v.
The charging method and charging unit of the present invention, including the first charge step and the second charge step, the first charging stepSuddenly it is charged by Charge Management unit 2, when detecting that charging current reaches predetermined threshold value, the Charge Management unit 2Stop charging, generate control signal, then, TCU transfer control unit 4 will be switched into according to control signal to the second charge stepIt charges, TCU transfer control unit 4 starts voltage regulation unit 3 and charges, and controls voltage regulation unit 3 and stop charging；This charging sideFor method compares existing charging method, in the first charging stage, basic charging can be carried out to baby battery, works as Charge ManagementSince charging current is smaller, and when stopping charging, Charge Management unit 2 will continue to generate control signal, the control signal unit 2It is that baby battery equipment continues to charge that TCU transfer control unit 4, which will be started, and start voltage regulation unit 3, in charging process, passes through conversion and controlUnit 4 controls voltage regulation unit 3 and stops charging.
Low current charge equipment can be filled to by 4.2V by battery, be made up by above-mentioned charging method and charging unitThe case where battery can not be filled to 4.2v by normal charge managing chip, realizing low current can also charge, to improveThe service efficiency of baby battery overcomes since baby battery equipment self-capacity is with regard to small, and is not fully filled the problem of electricity.
It would be recognized by those skilled in the art that it is possible to make numerous accommodations to above description, so embodiment is onlyFor describing one or more particular implementations.
Although having been described and describing the example embodiment for being counted as the present invention, it will be apparent to those skilled in the art thatIt can be variously modified and is replaced, without departing from the spirit of the present invention.Furthermore it is possible to make many modifications with will be specialCondition of pledging love is fitted to the religious doctrine of the present invention, without departing from invention described herein central concept.So the present invention is unrestrictedIn specific embodiment disclosed here, but the present invention may further include belonging to all embodiments of the scope of the invention and its being equalObject.