CN204949525U

CN204949525U - Constant voltage output electron cigarette device

Info

Publication number: CN204949525U
Application number: CN201520716504.3U
Authority: CN
Inventors: 方建平
Original assignee: XI'AN TUOER MICROELECTRONICS CO Ltd
Current assignee: Hangzhou Toll Microelectronic Co ltd
Priority date: 2015-09-16
Filing date: 2015-09-16
Publication date: 2016-01-13
Anticipated expiration: 2025-09-16

Abstract

The utility model provides an electron cigarette device, its characterized in that guarantees to keep the unanimity at the voltage of whole battery voltage 3.5-4.2 within range outputs, the balanced uniformity of voltage range's smoking effect entirely of furthest, and its inside main smoking detection module that includes, control module, switch drive circuit, LED drive circuit, wherein control module mainly includes system state judge module, switch battery voltage 0 and LED battery voltage 0, switch control circuit includes battery voltage detection module and analog circuit module.

Description

A kind of constant voltage exports electronic cigarette device

Technical field

The utility model relates to a kind of constant voltage and exports electronic cigarette device.

Background technology

Present stage, electronic cigarette all adopted the structure as Fig. 1, comprise pneumatic sensor, control chip, internal battery, tobacco tar and heater strip assembly and indicator lamp five part composition, concrete annexation as shown in Figure 2, pneumatic sensor is held with sampling end SENS and VSS of control chip and is connected, internal battery anode is connected with the vdd terminal of control chip, and negative terminal is held with the VSS of control chip and is connected; Tobacco tar and heater strip assembly are held with output OUT and VSS of control chip and are connected; Indicator lamp is held with the LED of control chip respectively and VSS holds and is connected.Wherein the smoking action of user is mainly converted into the change of the electrology characteristic that control chip can identify by pneumatic sensor, facilitates control chip to sample; Control chip is mainly through the output signal of sampling air flow sensor, judgement system present stage is in standby or smoking state, and according to different condition adjudgement results, control heater strip and indicator lamp and make corresponding action, meet the organoleptic requirements such as the vision of user in smoking process and the sense of taste; Internal battery is the energy source of the inner all parts of electronic cigarette, also be the critical piece determining electronic cigarette service life, tobacco tar and heater strip assembly mainly ensure in smoking process, and when heating wire temperature rises, tobacco tar is fully atomized, and meets the smoking experience of user; Indicator lamp is mainly used to the flame display effect in simulated smoking process, makes every effort to reach vivid effect.

Control chip internal frame diagram as shown in Figure 3, comprises smoking detection module, control module, Switch drive circuit, LED drive circuit and switching device.Smoking detection module for detecting the output of pneumatic sensor, and judges which kind of state is system be in; Control module exports suitable control signal according to the state of system respectively to LED drive circuit and Switch drive circuit; LED drive circuit is used for the drive singal control signal of LED being converted into indicator lamp; Switch drive circuit is used for Switch control signal to be converted into actual switching drive signal.

Traditional electronic cigarette control chip by detecting the output of pneumatic sensor, state residing for judgement system (smoking or standby), and then the conducting of gauge tap device controls whether have electric current in heating wire, as Fig. 4 with cut-off.Wherein the control end Con of switching device is connected with the driver module of heating wire, positive termination anode V+, and negative terminal connects heating wire, and negative terminal and the battery negative terminal V-of heating wire and switching device are connected.

Under traditional controlling mechanism, the power of the heating wire in each smoking cycle is Vdd ²/ R, wherein, Vdd is cell voltage, and R is the average resistance (here because switch conduction resistance is less, We conducted and ignore) of heating wire.This power output and supply voltage in close relations.

But different from actual cigarette, the energy of electronic cigarette comes from internal cell completely, along with the increase of electronic cigarette service time, the electricity of battery reduces gradually, shows as the reduction of cell voltage.Original electronic cigarette chip is by the current path of a switch controlled heater strip, when smoking state being detected, switching tube is opened by controller, heater strip has the electric current of approximate Vdd/R (not considering switch conduction resistance), along with the reduction of cell voltage, the reduction that this heating current is also proportional, this efficiency of heating surface just producing user's in use heater strip can reduce, and shows that the smoking experience of user can be deteriorated along with the use of electronic cigarette.

Based on above problem, market has occurred design a kind of voltage detecting circuit at chip internal, in different voltage section, produce different dutycycles by digital circuit, which effectively reduces the deviation of output voltage average value in whole battery voltage range.

In order to reduce the correlation of output voltage and cell voltage, main employing at present as shown in Figure 5, battery voltage detection and PWM control module is increased in Switch control circuit inside, be data signal by analog to digital conversion circuit by cell voltage change transitions, and control the dutycycle of the switching tube under certain cell voltage condition by it.

But aforesaid way is owing to adopting digital circuit, determine which kind of dutycycle is digital circuit produce by the analog-to-digital conversion mode detecting cell voltage, cell voltage continuous transformation cannot be realized export, the characteristic that voltage stabilization keeps, the duty cycle adjustment of segmentation can only be realized, (especially at the critical voltage point of two dutycycles in whole battery voltage range, output voltage saltus step by a relatively large margin can be produced), and consider the scale of circuit, it is very high that analog-to-digital precision can not be done, Fig. 6 and Fig. 7 principle that to be the mode that adopts digital circuit segmentation to select regulate dutycycle and output voltage schematic diagram.

Wherein between Fig. 6 indication circuit inner setting 3 dutycycle selection areas, be respectively D2, D1 and D0 (D2>D1>D0).Fig. 7 represents the output voltage change schematic diagram of this control mode in whole battery voltage range, can obviously find out from figure, in whole battery voltage range, the degree of correlation of output voltage and cell voltage has the trend diminished, but as described above, which only can realize the duty cycle adjustment of segmentation, at two dutycycle switching point places, the significantly saltus step of output voltage can be produced, and will eliminate or reduce this problem and can only increase segmentation number.

Summary of the invention

Based on above problem, the utility model proposes and a kind ofly detect the implementation that cell voltage regulates dutycycle automatically, both meet cell voltage change, kept the effect of output voltage stabilization, turn avoid the demand that digital implementation needs the analog to digital conversion circuit introducing degree of precision simultaneously.

For reaching above object, a kind of constant voltage of the present utility model exports electronic cigarette chip and adopts following technical scheme:

Accompanying drawing explanation

Fig. 1 is the structural representation of existing electronic cigarette;

Fig. 2 is the circuit connection diagram of existing electronic cigarette;

Fig. 3 is existing electronic cigarette control chip internal frame diagram;

Fig. 4 is that existing electronic cigarette control chip is by detecting the output of pneumatic sensor, the view residing for judgement system;

Fig. 5 is existing electronic cigarette control module internal frame diagram;

Fig. 6 is the principle schematic that the mode adopting digital circuit segmentation to select regulates dutycycle;

Fig. 7 is the output voltage change schematic diagram of this control mode in whole battery voltage range;

Fig. 8 is by triangular wave square wave performance period schematic diagram.

Fig. 9 realizes the constant analog circuit connection layout of output voltage.

Figure 10 is the analog result schematic diagram of two kinds of different control modes output voltages.

Detailed description of the invention

The utility model has walked around the segmenting of digital circuit duty cycle adjustment, utilizes analog circuit can produce the feature of continuous print duty cycle adjustment, and the output characteristics of electronic cigarette is optimized further.

Design an output voltage Vref and do not produce circuit (for analog circuit than being easier to realize) with the internal reference voltage of cell voltage change, and by internal circuit realize one with the voltage of cell voltage change in direct ratio, i.e. K*Vbat (wherein K is proportionality coefficient).By the adjustment in later stage, the precision of Vref at least can reach ± and 1%.

The triangular wave of Fig. 8 can be realized by internal comparator and charge-discharge circuit, utilize the triangular wave in Fig. 8 to be easy to realize the cycle square wave of dutycycle D=Ton/ (Ton+Toff), be equivalent to:

D＝Vref/(K*Vbat)

Because output equivalent voltage is:

Vout＝D*Vbat

Namely

Vout＝Vref/(K*Vbat)*Vbat＝Vref/K

Have nothing to do with cell voltage, achieve the constant of output voltage, aforesaid way dutycycle presents continuous print change along with the change of Vbat, carry out output voltage in this manner hardly with the change of output voltage, Fig. 9 is the connection diagram of this circuit, as shown in FIG., comprising:

1.Vref module: produce and the incoherent reference voltage Vref of supply voltage.

2.Sens module: sampling battery voltage Vbat, and COEFFICIENT K exports a voltage Vout=K*Vbat according to a certain percentage.

3.Isource module: produce and the incoherent constant-current source electric current of supply voltage.

4.Comp1 and Comp2 module: the magnitude of voltage comparing input positive and negative terminal, and output logic level, exports as high level when positive terminal voltage is greater than negative terminal voltage.

5.Cap electric capacity: the voltage waveform output current of Isource being converted into certain slope.

6.Switch switch: the signal detecting Logic circuit, determines whether discharge to Cap electric capacity.

7.Logic module: by the combinational logic of the output signal of Comp1 and Comp2 by inside, be converted into the square-wave signal with certain dutycycle of equivalence, as shown in Figure 9, the output of Vref is connected with the negative terminal of Comp1 its annexation; The output of Sens is connected with the negative terminal of Comp2; The anode of Isource is connected with Vbat, the anode of negative terminal and Comp1, the anode of Comp2, and the anode of electric capacity Cap with Switch is connected, the negative terminal of Cap and the negative terminal of Switch are connected with GND, the output of Comp1 and Comp2 is connected with input I1 and I2 of Logic, and the FB end of Logic is connected with the control end of Switch.

Specific works process is:

After circuit start, Vref exports constant reference voltage Vref, simultaneously Sens module samples cell voltage Vbat according to fixed proportion output voltage K*Vbat, constant-current source Isource charges to electric capacity Cap, along with the rising of Vcap, the output signal of Comp1 and Comp2 sends into input I1 and I2 of Logic, Logic exports FB signal according to input signal, Cap electric capacity is discharged, Vcap is made to be periodic sawtooth waveforms, output pwm signal simultaneously, this signal is the square wave of dutycycle along with Vbat real-time change of our needs.

Figure 10 is the analog result figure of the output voltage of two kinds of different control modes, as can be seen from Figure 10 also, although the implementation of digital circuit before reduces the degree of correlation of output voltage and cell voltage, but still have larger deviation, and have significantly segmented characterizing, and adopt the control mode output voltage of analog regulation only to have less error in whole cell voltage interval.

Claims

1. a constant voltage exports electronic cigarette device, comprise system mode judge module, Switch control circuit module and LED control circuit module, described system mode judge module is connected with LED control circuit module with Switch control circuit module respectively, described Switch control circuit module comprises battery voltage sensing module and analog module, described battery voltage sensing module is connected with analog circuit, it is characterized in that, described analog circuit detects cell voltage in real time, by cell voltage determination output duty cycle, output voltage is made to keep constant.

2. a kind of constant voltage according to claim 1 exports electronic cigarette device, and it is characterized in that, described analog module comprises Vref module, Sens module, Isource module, Comp1 and Comp2 module, Cap electric capacity and Logic module.

3. a kind of constant voltage according to claim 2 exports electronic cigarette device, and it is characterized in that, the described output of Vref module is connected with the negative terminal of Comp1; The described output of Sens module is connected with the negative terminal of Comp2, the anode of described Isource module is connected with Vbat, the anode of negative terminal and Comp1, the anode of Comp2, and Cap electric capacity is connected with the anode of Switch, the described negative terminal of Cap electric capacity and the negative terminal of Switch are connected with GND, the described output of Comp1 with Comp2 module is connected with the input of Logic, and the FB end of described Logic module is connected with the control end of Switch.