CN104703343B - A kind of intelligent PWM drive circuit - Google Patents
A kind of intelligent PWM drive circuit Download PDFInfo
- Publication number
- CN104703343B CN104703343B CN201510060339.5A CN201510060339A CN104703343B CN 104703343 B CN104703343 B CN 104703343B CN 201510060339 A CN201510060339 A CN 201510060339A CN 104703343 B CN104703343 B CN 104703343B
- Authority
- CN
- China
- Prior art keywords
- module
- resistance
- connection
- phase input
- logical operation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection
Abstract
The invention provides a kind of intelligent PWM drive circuit, the present invention to the power supply in USB data line and ground wire by carrying out current detecting, Discrete control and the pwm signal for producing different frequency, the signal will control LED in series via it is permanent it is bright, low frequency is glittering, high frequency is glittering and the multiple-working mode such as shut-off.It includes current detection module, voltage transformation module, reference voltage module, comparison module, logical operation module, oscillator module, driver element, LED indicating members, current detection module connects voltage transformation module, voltage transformation module connects the in-phase input end of comparison module, the out-phase input connection reference voltage module of comparison module, the output end connection logical operation module of comparison module, logical operation module connection oscillator module, logical operation module connects driver element, driver element connection LED.
Description
Technical field
The present invention relates to electronic technology field, there is provided a kind of intelligent PWM drive circuit.
Background technology
With the development of society and the progress of science and technology, developing rapidly and vigorously for electronic technology causes the renewal day of electronic product
It is increasingly fast, be gradually intended to full-featured, outward appearance is unique, it is easy to use, follow the fashion and innovated with practical, individual requirement experience
Develop Deng direction, so as to each electronic product such as mobile phone, Pad, laptop computer, camera, have become must in people's daily life
The problem of indispensable part, having become the closely bound up part of people's life, and facing a charging more electronic product,
Electronic product can not intuitively observe charge condition when charging.
The content of the invention
The present invention by carrying out current detecting to the power supply in USB data line and ground wire, Discrete control simultaneously produces difference
The pwm signal of frequency, the signal will control LED in series via it is permanent it is bright, low frequency is glittering, high frequency is glittering and shut-off etc.
Multiple-working mode.
The present invention uses following technical scheme to achieve these goals：
A kind of intelligent PWM drive circuit, it is characterised in that including current detection module, voltage transformation module, reference voltage
Module, comparison module, logical operation module, oscillator module, driver element, LED indicating members, current detection module connection electricity
Modular converter is pressed, voltage transformation module connects the in-phase input end of comparison module, the out-phase input connection reference of comparison module
Voltage module, the output end connection logical operation module of comparison module, logical operation module connection oscillator module, logical operation
Module connects driver element, driver element connection LED.
Above-mentioned technical proposal, the current detection module include resistance R4-R6, the first operational amplifier, and the first computing is put
The out-phase input of big device connects USB positive electricity ends by resistance R5, and the in-phase input end of the first operational amplifier passes through series connection
Resistance R4, electronics R6 connection USB positive electricity ends.
Above-mentioned technical proposal, the voltage transformation module include FET Q1, resistance R7, and FET Q1 grid connects
First operational amplifier output terminal, drain electrode the first operational amplifier in-phase input end of connection, source electrode connection resistance R7, resistance R7 are another
One end is grounded.
Above-mentioned technical proposal, reference voltage module include the second operational amplifier OP, resistance R1-R3, number of parallel 1:N
PNP pipe Q1 and PNP pipe group Q2, resistance R1 is connected between the second operational amplifier OP out-phase input and output end, electricity
Resistance R2 is connected between the second operational amplifier OP in-phase input end and output end, resistance R3 the second operational amplifiers of connection OP
In-phase input end and PNP pipe group Q2 emitter stage, triode Q1 emitter stage connects the second operational amplifier OP out-phase input
End, the second operational amplifier OP output end is by the resistance eutral groundings of 4 series connection, and the voltage between resistance is as the reference voltage two-by-two
Output.
Above-mentioned technical proposal, the comparison circuit include 3 comparators, and the in-phase input end of 3 comparators is all connected with electricity
Hindering the connection end of R7 and FET Q1 source electrodes, out-phase input connects the reference voltage output terminal of reference voltage module respectively, and 3
The output end connection logical operation module of individual comparator.
Above-mentioned technical proposal, the comparison circuit include 3 comparators, and the in-phase input end of 3 comparators is all connected with electricity
Hindering the connection end of R7 and FET Q1 source electrodes, out-phase input connects the reference voltage output terminal of reference voltage module respectively, and 3
The output end connection logical operation module of individual comparator.
Above-mentioned technical proposal, Bit1-Bit3 are output control signal caused by comparator module, alternative selector mould
The input signal of block is respectively 1Hz and 2Hz pwm control signal, and by Bit1-Bit3 logical combination, alternative is selected
Device enter line frequency selection and it is permanent open or the control signal output of permanent shut-off, with this, to realize, driving MOS device is opened
Close control.
Above-mentioned technical proposal, oscillator module include the reference current circuit being sequentially connected, comparator circuit and frequency dividing
Circuit；
Reference current circuit, high-order the comparison reference voltage VREF_H and low level that comparator is taken out by divider resistance compare
Reference voltage VREF_L, follow circuit to produce the reference circuit of charging and discharging currents using the operational amplifier OP sources formed, pass through
Out-phase input to comparator COMP is provided after mirror image after circuit, provides charging and discharging when high-order and low level compares respectively
Electric current,
Comparator circuit includes a high-speed comparator COMP and formed, and comparator negative terminal voltage VN joins with high bit comparison respectively
Examine voltage VREF_H and low level comparison reference voltage VREF_L is compared and overturn, so as to realize that the vibration of certain frequency is believed
Number.Frequency dividing circuit, computing and choosing are carried out into logical operation module to export 1Hz and 2Hz frequency using d type flip flop (DFF)
Select.
The present invention is because use above-mentioned technical proposal, therefore possess following beneficial effect：
The present invention is realized by the design of application specific integrated circuit distinguishes different charged states using single LED lamp, periphery
Circuit structure is simple, and the accuracy of detection of different charged states is high.The usage quantity that traditional method saves LED etc. is compared to, is subtracted
The PCB surface product and socket volume of mini system scheme.
Brief description of the drawings
Fig. 1 is the block diagram of the present invention；
Fig. 2 is the circuit diagram of the present invention；
Fig. 3 logic module circuits of the present invention；
Fig. 4 is voltage detection module figure of the present invention；
Fig. 5 is the reference voltage module circuit diagram of the present invention；
Fig. 6 is the comparator circuit figure of the present invention；
Fig. 7 is logical sum pierce circuit.
Embodiment
Fig. 4 is current detecting and voltage conversion circuit, and R4 is detection resistance, and it is IL to flow through electric current, due to amplifier input two
Terminal voltage is equal, therefore has VP1=VN1, it is assumed that D+in terminal voltages are VDP, and D+out terminal voltages are VDN, resistance R6=R5, then
Have：
VDN=VDP+IL*R4
VP=VDN+Io*R5
VDN=VN1
Io=(VDN-VP)/R6
4 formulas can calculate more than：Vsense=Io*20R5=20*IL*R5
That is, for given resistance R4, output voltage directly reflects the size for the electric current for flowing through detection resistance.
Reference voltage Vout with detection voltage Vsense by comparator relatively after drive driving FET Q2 and Q5, from
And LED and music module is driven to work.
Fig. 5 is generating circuit from reference voltage
OP is operational amplifier in Fig. 1, and Q1, Q2 are that number of parallel is 1：N PNP pipe.Due to amplifier both ends VP, VN voltage
It is equal, i.e. VP=VN, and the number of parallel of PNP pipe ratio is 1：N (is used generally 1 in circuit design:8) so that Q1's and Q2
Vbe forms voltage difference of the value for △ Vbe, with reference to amplifier characteristic, it may be determined that the voltage difference at resistance R3 both ends is exactly △
Vbe, this is the voltage of a positive temperature coefficient.The electric current for flowing through resistance R3 is △ Vbe/R3, can thus calculate Vout
Voltage：Vout=Vbe2+ (△ Vbe/R3) * (R3+R2)
Because Vbe2 is the voltage of negative temperature coefficient, therefore, the voltage superposition of positive and negative two temperatures coefficient, it is possible to design
The voltage of one zero-temperature coefficient.After Vout is carried out into partial pressure by resistance, it is possible to obtain multichannel reference voltage.
Fig. 6 is a high-speed comparator with positive feedback.
MP1, MP2 are that comparator is inputted to pipe, and when INP terminal voltages are higher than INN terminal voltages, the electric current for flowing through MP2 reduces,
MP1 electric current increase is flowed through, meanwhile, A points voltage rise, B points voltage reduces so that the electric current for flowing through M1 reduces, and flows through M2's
Electric current increases, and further promotes the electric current for flowing through MP1 all to flow through M3, and equally, the electric current for flowing through MP2 is walked more, stream by M2 points
The electric current for crossing M4 further reduces, and by M3, M5 and M4, after this two groups of current mirror mirror images of M6, flows through M8 electric current much larger than stream
M6 is crossed, so that output voltage OUT is pulled to high level.Similarly, if INP voltages are less than INN terminal voltages, above analysis is opposite i.e.
Can.
Fig. 3 is logical operation module, and PWM controls truth table
| Bit1 | Bit2 | Bit3 | State or frequency (f) |
| 0 | 0 | 0 | Go out |
| 0 | 0 | 1 | 2Hz |
| 0 | 1 | 0 | 1Hz |
| 1 | x | x | It is permanent bright |
Logical operation combination PWM controls truth table to analyze.1Hz and 2Hz vibration frequency is produced by oscillator, and bit1~
3 are produced by comparator array.Work as bit1, bit2, when bit3 is 0, PWM exports 0 level, closes outside LED paths, LED etc.
Go out.When bit3 is high level, bit2, when bit3 is 0 level, selector selects 2Hz frequencies, is dodged through PWM output controls LED etc.
It is bright；When bit2 is high level, when remaining is 0 level, selector selects 1Hz frequencies, is flashed through PWM output controls LED etc.；When
When bit1 is high level, PWM is permanent to be high, and LED etc. is permanent bright.
This oscillator is mainly made up of three parts, is reference current circuit respectively, more electric and frequency dividing circuit this three
Part.
Reference current circuit, the high-order comparison reference voltage of comparator, and low level comparison reference are taken out by divider resistance
Voltage.Follow circuit to produce the reference circuit of charging and discharging currents using by the operational amplifier OP sources formed simultaneously, enter mirror image
Negative terminal to comparator COMP is provided afterwards, is provided when high-order and low level compares be charged and discharged electric current respectively.Comparator circuit
Mainly be made up of a high-speed comparator COMP, comparator negative terminal voltage VN respectively with high-order (VREF_H) and low level (VREF_L)
Reference voltage is compared and overturn, so as to realize the oscillator signal of certain frequency.Frequency dividing and logical operation circuit, it is main to utilize
D type flip flop (DFF) realizes division function, and final output 1Hz and 2Hz frequency enters logical operation module and carry out computing and choosing
Select.
Claims (5)
1. a kind of intelligent PWM drive circuit, it is characterised in that including current detection module, voltage transformation module, reference voltage mould
Block, comparison module, logical operation module, oscillator module, driver element, LED indicating members, current detection module connection voltage
Modular converter, voltage transformation module connect the in-phase input end of comparison module, and the out-phase input connection of comparison module is with reference to electricity
Die block, the output end connection logical operation module of comparison module, logical operation module connection oscillator module, logical operation mould
Block connects driver element, driver element connection LED；
The current detection module includes resistance R4-R6 and the first operational amplifier, the out-phase input of the first operational amplifier
USB positive electricity ends are connect by resistance R5, resistance R4 by series connection of the in-phase input end of the first operational amplifier, resistance R6 connections
USB positive electricity ends.
2. a kind of intelligent PWM drive circuit according to claim 1, it is characterised in that the voltage transformation module includes
FET Q1, resistance R7, FET Q1 grid connect the first operational amplifier output terminal, drain electrode the first operation amplifier of connection
Device in-phase input end, source electrode connection resistance R7, resistance R7 other ends ground connection.
A kind of 3. intelligent PWM drive circuit according to claim 1, it is characterised in that：Reference voltage module includes second
Operational amplifier OP, resistance R1-R3, number of parallel 1:N PNP pipe Q1 and PNP pipe group Q2, resistance R1 is connected to the second computing
Between amplifier OP out-phase input and output end, resistance R2 is connected to the second operational amplifier OP in-phase input end and defeated
Go out between end, resistance R3 the second operational amplifiers of connection OP in-phase input end and PNP pipe group Q2 emitter stage, triode Q1's
Emitter stage connects the second operational amplifier OP out-phase input, and the second operational amplifier OP output end passes through 4 electricity connected
Resistance ground connection, the voltage between resistance exports as the reference voltage two-by-two.
4. according to any described a kind of intelligent PWM drive circuit in claim 1-3, it is characterised in that：The comparison module
Including 3 comparators, the in-phase input end of 3 comparators is all connected with resistance R7 and FET Q1 source electrodes connection end, out-phase
Input connects the reference voltage output terminal of reference voltage module, the output end connection logical operation module of 3 comparators respectively.
5. a kind of intelligent PWM drive circuit according to claim 4, Bit1-Bit3 is output control caused by comparator module
Signal processed, the input signal of alternative selector module are respectively 1Hz and 2Hz pwm control signal, pass through Bit1-Bit3's
Logical combination, the control signal output of line frequency selection and permanent unlatching or permanent shut-off is entered to alternative selector, is come with this
Realization drives the switch of MOS device to control.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510060339.5A CN104703343B (en) | 2015-02-05 | 2015-02-05 | A kind of intelligent PWM drive circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510060339.5A CN104703343B (en) | 2015-02-05 | 2015-02-05 | A kind of intelligent PWM drive circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104703343A CN104703343A (en) | 2015-06-10 |
| CN104703343B true CN104703343B (en) | 2017-11-24 |
Family
ID=53350004
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510060339.5A Expired - Fee Related CN104703343B (en) | 2015-02-05 | 2015-02-05 | A kind of intelligent PWM drive circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104703343B (en) |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7525291B1 (en) * | 2003-01-21 | 2009-04-28 | Microsemi Corporation | Linearly regulated battery charger |
| JP2011108529A (en) * | 2009-11-18 | 2011-06-02 | Phoenix Electric Co Ltd | Power supply circuit for led |
| CN102539895A (en) * | 2010-12-15 | 2012-07-04 | 鸿富锦精密工业（深圳）有限公司 | USB (universal serial bus) port detecting circuit |
-
2015
- 2015-02-05 CN CN201510060339.5A patent/CN104703343B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN104703343A (en) | 2015-06-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102928760B (en) | LED aging testing system and method for testing thereof | |
| CN102290978B (en) | Power management system | |
| CN105676928B (en) | A kind of band-gap reference circuit | |
| CN101895246A (en) | Control pulse generating circuit and regulating system and method of direct current brushless motor speed | |
| CN103869857B (en) | Constant current and constant power realize circuit and method | |
| CN103944375B (en) | PFC control circuit and PFC circuit with same used | |
| CN106209066A (en) | A kind of method of multiplexing chip pins and chip | |
| CN103885519B (en) | Low voltage bandgap reference circuit | |
| DenHerder | Design and simulation of photovoltaic super system using Simulink | |
| Zebulum et al. | Analog circuits evolution in extrinsic and intrinsic modes | |
| CN108957065A (en) | A kind of electronic load circuit | |
| CN205945689U (en) | Multiplexing chip of chip fin | |
| CN104703343B (en) | A kind of intelligent PWM drive circuit | |
| CN107478890A (en) | A kind of current sensing means for integrated circuit | |
| CN104348431B (en) | Common-mode feedback differential amplification circuit, method and integrated circuit | |
| CN106339025B (en) | A kind of low voltage high-precision band-gap reference circuit applied to Internet of things node | |
| CN103457465A (en) | Constant-current/constant-voltage DC-DC conversion system with external adjustable current-limiting function | |
| CN205811977U (en) | A kind of pwm control signal produces circuit | |
| CN106598900B (en) | LVDS driver circuit | |
| CN102437735A (en) | Switch power supply and divider therefor | |
| CN208572492U (en) | A kind of bright driving circuit of the constant current of wide input voltage and device | |
| CN101586987B (en) | Temperature sensing circuit suitable for operation at low voltage | |
| Shamshiddinov et al. | Use Of Electronic Keys To Increase Energy Savings Of Led Lights | |
| CN106292815B (en) | Low dropout voltage regulator and the output buffer comprising low dropout voltage regulator | |
| CN104753318B (en) | A kind of Switching Power Supply for being depressured negative boosting |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20171124 Termination date: 20220205 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |