CN104883800B - GHz high-speed LED optical communication driver - Google Patents

Abstract

The invention discloses a GHz high-speed LED optical communication driver. A power supply module is used for outputting a needed constant voltage for supply, and limiting an output current. An LED working module consists of a resonant cavity, an LED, and a K101. A control module comprises a PWM generation device, a positive Buffer and a negative Buffer, and is used for the on/off control of the switch K101. A constant current module consists of a resistor, a capacitor, and an operational amplifier. The cathode of the LED is sequentially connected with the switch K101 and the resistor in a series manner, and then is grounded. The resonant cavity is in parallel connection with the LED. One end of a current-limiting constant voltage unit is connected with the anode of the LED, and the other end of the current-limiting constant voltage unit is grounded. An output end of the PWM generation device is connected with the input end of the positive Buffer and the input end of the negative Buffer at the same time. The output ends of the positive Buffer and the negative Buffer output control signals so as to control the switch K101. The driver can achieve the high-speed on/off of the switch K101, thereby achieving the superspeed light modulation of the LED.

Description

A kind of GHz high speeds LED light communications driver

Technical field

The present invention relates to a kind of LED light communication drives, more particularly to a kind of a kind of LED high speed optical communications driver of high speed.

Background technology

LED light communication technology is a kind of brand-new communication technology for progressively growing up in recent years, many related technologies Research is also in the starting stage, and the especially technology in high speed LED component, high-speed switching circuit is even more almost blank.Optic communication is Superfast photoswitch speed is realized, and is not the speed-sensitive switch in circuit common, this point it is emphasized that the switch speed of light Rate, and the switching rate in non-electronic or hole.Deficiency of the optic communication to wireless communications applications such as supplementary WIFI, in some fields Substituting WIFI becomes a kind of brand-new communication mode.LED light communication technology is progressively grow up in recent years a kind of brand-new Communication technology, many related technical research are also in the starting stage, especially in high speed LED component, the skill of high-speed switching circuit Art is even more almost blank.LED is connected one and switchs the field for carrying out that simple modulation is brand-new developing, and LED light communication needs one The driving modulation circuit of individual high speed is supported, at present in the superfast modulation solution that a system is there is no using in.

The content of the invention

The technical problem to be solved is for above-mentioned the deficiencies in the prior art, there is provided a kind of high speed LED light is led to Letter driver, the present invention relates to a kind of LED high speed optical communications driver can realize the superfast LED light modulations of the GHz of system.

To realize above-mentioned technology, the present invention is adopted the technical scheme that：A kind of GHz high speeds LED light communications driver, including Power supply unit, LED operation module, switch control module and constant flow module；It is characterized in that：Supply module is powered by current limliting constant pressure Unit is constituted, and powers and output current is limited for being adapted to the constant pressure needed for output；LED operation module by resonator cavity, LED and switch K101 are constituted；Control module includes PWM generating meanss, positive electricity Buffer, negative electricity Buffer, for switch K101 carries out on-off control；Constant flow module is made up of resistance, electric capacity and amplifier；The negative electrode of LED is gone here and there successively with switch K101, resistance It is grounded after connection；Resonator cavity is in parallel with LED；Current limliting constant pressure unit one end is connected with LED anode, other end ground connection；PWM generating meanss Output be simultaneously connected with the input and negative electricity Buffer inputs of positive electricity Buffer；The outfan and negative electricity of positive electricity Buffer Buffer outfan output control signals are with controlling switch K101；The in-phase input end ground connection of amplifier, inverting input and resistance The connection of ungrounded end；Electric capacity C1 is connected between the outfan of the inverting input and amplifier of amplifier；The outfan of amplifier is also It is connected with pressure limiting constant current unit；

When PWM generating meanss produce a positive voltage, positive electricity Buffer and negative electricity Buffer driving switch K101 are open-minded, LED passes through current limliting constant pressure power supply unit and the positive power supply of constant flow module and produces the electric current of an overshoot, LED is quickly sent out Bright, now resonator cavity stores energy simultaneously；When PWM generating meanss produce a specific negative voltage when, positive electricity Buffer and bear Electric Buffer drives HEMT K101 to close, and resonator cavity produces a reverse spike voltage pair by resonance LED reverse power supply, to accelerate the shut-off of LED；The resonator cavity can control the time of reverse power supply Jing after control resonant parameter, To realize sequencing contro, make resonator cavity compare with the LED turn-off times.

As further improved technical scheme of the present invention, wave filter that the pressure limiting constant current unit includes being sequentially connected in series, Rectifier bridge and circuit for power conversion；The wave filter other end is AC input end, is input into for civil power；It is the filtering of civil power filtered device, whole Circuit for power conversion is entered after stream bridge rectification；The circuit for power conversion is suitable defeated to produce one for realizing DC-DC Constant pressure needed for going out is powered and output current is limited, and the voltage of output is tri- groups of Va, Vb and Vg.

As further improved technical scheme of the present invention, also including being connected between rectifier bridge and circuit for power conversion PFC；The PFC is used for Active PFC and produces a HVDC output, is disturbed with reducing the harmonic wave to civil power.

Used as further improved technical scheme of the present invention, switch K101 is HEMT.

Used as further improved technical scheme of the present invention, the control device includes frequency conversion engine, reference clock signal Source, reference power supply, voltage controlled oscillator, compensation network, programme-control and buffer；Also include electric capacity C2；Reference clock signal source, Reference power supply, voltage controlled oscillator, compensation network and programme controlled output are connected with frequency conversion engine respectively；The output of reference power supply Also it is connected with programme-control, programme controlled output is also connected with buffer simultaneously；Use after output series capacitance C2 of buffer In controlling switch K101.

PFC Chineses are：Active PFC, in the present invention, PFC is as power factor correction circuit, whole to increase The angle of flow of stream device, the waveform for correcting input current is allowed to follow voltage waveform to become ideal sine wave, so as to reduce Input harmonics content, improves interfering for electrical network.Further, since the decline of harmonic content also causes the disturbance of rear stage system Composition is reduced, and improves the performance of system.PWM is the abbreviation of English " Pulse Width Modulation ", and abbreviation pulsewidth is adjusted System, is a kind of method of high frequency chopping, and the work(to output parameter precise control is realized by the size of dutycycle in regulating cycle Energy.

The operation principle of the present invention：a：Current limliting constant pressure power supply unit is to provide supply module；Wherein AC input is civil power Input, wave filter is to be filtered, and rectifier bridge is to carry out rectification, and PFC is to carry out Active PFC and produce a high straightening Stream output, PFC module only reduce the harmonic wave to civil power and disturb, and circuit for power conversion is to realize DC-DC to produce one It is adapted to the constant pressure needed for output to power and limit output current, the voltage of output is tri- groups of Va, Vb and Vg and more Other group of output voltage；b：Resonator cavity, LED and switch K101 constitute LED operation module；c：PWM generating meanss and positive electricity Buffer, negative electricity Buffer constitute the control module of the on-off control to switching K101, and the control module is above all realized The power supply of positive and negative voltage, uses " relative " level conversion method, and such as Fig. 3, Vg give control chip simultaneously as control chip Ground, and Vg<0, ground connection when in other words the ground of control chip to be less than LED operation, but the power supply Vvco needed for chip and Vref must be positive, then Va=Vvco+Vg relative to Vg>0, Vb=Vref+Vg>0, control is then capable of achieving by the value for adjusting Vg The output of coremaking piece is driven for positive and negative voltage relative to ground connection during LED operation, and while realizes ultrahigh speed control (because being Immediately produced by control chip, there is no the demand of conversion time, simply power consumption is increased slightly)；d：Resistance, electric capacity and amplifier are constituted Constant flow module.

When control chip produces a high level (level when this high level is relative to LED operation is for just), by just Electric Buffer and negative electricity Buffer drives HEMT K101 open-minded, and LED is by civil power by changing what is produced Forward voltage is powered and produces the electric current of an overshoot, and LED is quickly shinny, and now resonator cavity stores energy simultaneously.Work as control When coremaking piece produces a specific low level (this low level is negative relative to level during LED operation), by positive electricity Buffer and negative electricity Buffer drives HEMT K101 to close, and resonator cavity produces a reversely point by resonance Peak voltage accelerates the electricity shut-off of LED to LED reverse power supply.In addition, can strictly control reversely confession by precise control resonant parameter The time of electricity namely sequencing contro method so as to can compare with the LED electricity turn-off times, so as to the current-carrying for avoiding band curvature from being brought Sub- radiation recombination efficiency declines and accelerates light shut-off speed.

So-called overshoot is open-minded, refers to that LED is in momentary excess current working condition in the ascent stage for starting, subsequently just enters The constant current operation state of stable state.So-called electricity shut-off and light shut-off refer to that LED actually has two turn off process, one be will be additional What is carried is electrically cut off, referred to as electricity shut-off, and now LED can't extinguish at once, but just extinguish after a bit of time；Light Extinguishing be referred to as light shut-off, then, it is corresponding also to have electric-opening and light to open, in other words, the electricity of LED and just have Certain sequential relationship.

The present invention can realize the GHz high speed open and close for switching K101, so as to realize the high speed light modulation to LED.With tradition Simply one regular tap pipe of series connection is modulated difference to LED, present invention employs the resonance method, overshoot and opens method, reversely notes Entering method, band curvature corrective method, the sequencing contro of innovation and relative level transformation approach, positive/negative-pressure drives method to go to drive one newly The HEMT of type, such as HEMT device, which works in linear amplification state, and provides the GHz of a system Ultrahigh speed drives solution.

Description of the drawings

Fig. 1 is the principle general diagram of the present invention.

Fig. 2 be the present invention realize theory diagram.

Fig. 3 is the LED drive circuit parsing schematic diagram of the present invention.

Below in conjunction with the accompanying drawings the specific embodiment of the present invention is described further.

Specific embodiment

Embodiment 1

Referring to Fig. 1, a kind of this GHz high speeds LED light communications driver, including power supply unit, LED operation module, switch control Molding block and constant flow module；It is characterized in that：Supply module is made up of current limliting constant pressure power supply unit, for being adapted to needed for output Constant pressure is powered and output current is limited；LED operation module is made up of resonator cavity, LED and switch K101；Control module bag PWM generating meanss, positive electricity Buffer, negative electricity Buffer are included, for on-off control being carried out to switching K101；Constant flow module is by electricity Resistance, electric capacity and amplifier are constituted；The negative electrode of LED is grounded after being sequentially connected in series with switch K101, resistance；Resonator cavity is in parallel with LED；Current limliting Constant pressure unit one end is connected with LED anode, other end ground connection；The output of PWM generating meanss input simultaneously with positive electricity Buffer End and negative electricity Buffer inputs connect；The outfan and negative electricity Buffer outfans output control signal of positive electricity Buffer is controlling System switch K101；The in-phase input end ground connection of amplifier, inverting input are connected with the ungrounded end of resistance；The anti-phase input of amplifier Electric capacity C1 is connected between end and the outfan of amplifier；The outfan of amplifier is also connected with pressure limiting constant current unit；

When PWM generating meanss produce a positive voltage, positive electricity Buffer and negative electricity Buffer driving switch K101 are open-minded, LED passes through current limliting constant pressure power supply unit and the positive power supply of constant flow module and produces the electric current of an overshoot, LED is quickly sent out Bright, now resonator cavity stores energy simultaneously；When PWM generating meanss produce a specific negative voltage when, positive electricity Buffer and bear Electric Buffer drives HEMT K101 to close, and resonator cavity produces a reverse spike voltage pair by resonance LED reverse power supply, to accelerate the shut-off of LED；The resonator cavity can control the time of reverse power supply Jing after control resonant parameter, To realize sequencing contro, make resonator cavity compare with the LED turn-off times.

Preferably, in the present embodiment 1, referring to Fig. 2, the pressure limiting constant current unit includes the filtering being sequentially connected in series Device, rectifier bridge and circuit for power conversion；The wave filter other end is AC input end, is input into for civil power；The filtered device filtering of civil power, Circuit for power conversion is entered after rectifier bridge rectification；The circuit for power conversion is adapted to producing one for realizing DC-DC Constant pressure needed for output is powered and output current is limited, and the voltage of output is tri- groups of Va, Vb and Vg.Also include being connected to PFC between rectifier bridge and circuit for power conversion；The PFC is used for Active PFC and produces a HVDC output, Disturbed with reducing the harmonic wave to civil power.Switch K101 is HEMT.The control device include frequency conversion engine, Reference clock signal source, reference power supply, voltage controlled oscillator, compensation network, programme-control and buffer；Also include electric capacity C2；Ginseng Examine signal source of clock, reference power supply, voltage controlled oscillator, compensation network and programme controlled output to be connected with frequency conversion engine respectively； The output of reference power supply is also connected with programme-control, and programme controlled output is also connected with buffer simultaneously；The output of buffer It is used for controlling switch K101 after series capacitance C2.

A kind of this course of work of LED high speed optical communications driver actually simply, is exactly two processes of on an off： When PWM generating meanss produce a positive voltage, drive HEMT K101 open-minded by Buffer, LED leads to Cross current limliting constant pressure supply module and the positive power supply of constant flow module and produce the electric current of an overshoot, LED is quickly shinny, now humorous Chamber shake while storing energy.When PWM generating meanss produce a specific negative voltage, high electron mobility is driven by Buffer Rate transistor K101 is closed, and resonator cavity produces a reverse spike voltage to LED reverse power supply by resonance, accelerates the electricity of LED Shut-off.In addition, time namely the sequencing contro method of reverse power supply can be strictly controlled by precise control resonant parameter so as to The LED electricity turn-off times can compare, and turn off light so as to avoid the carrier radiation recombination efficiency brought by band curvature from declining Speed is accelerated.

Claims (5)

1. a kind of GHz high speeds LED light communications driver, including power supply unit, LED operation module, switch control module and constant current Module；It is characterized in that：Supply module is made up of current limliting constant pressure power supply unit, is powered and right for being adapted to the constant pressure needed for output Output current is limited；LED operation module is made up of resonator cavity, LED and switch K101；Control module includes that PWM occurs dress Put, positive electricity Buffer, negative electricity Buffer, for switch K101 carry out on-off control；Constant flow module is by resistance, electric capacity and amplifier Constitute；The negative electrode of LED is grounded after being sequentially connected in series with switch K101, resistance；Resonator cavity is in parallel with LED；Current limliting constant pressure unit one end It is connected with LED anode, other end ground connection；The output of PWM generating meanss input and negative electricity simultaneously with positive electricity Buffer Buffer inputs connect；The outfan and negative electricity Buffer outfan output control signals of positive electricity Buffer is with controlling switch K101；The in-phase input end ground connection of amplifier, inverting input are connected with the ungrounded end of resistance；The inverting input and fortune of amplifier Electric capacity C1 is connected between the outfan put；The outfan of amplifier is also connected with pressure limiting constant current unit；

When PWM generating meanss produce a positive voltage, positive electricity Buffer and negative electricity Buffer driving switch K101 are open-minded, LED By current limliting constant pressure power supply unit and the positive electric current powered and produce an overshoot of constant flow module, make LED quickly shinny, this When resonator cavity simultaneously store energy；When PWM generating meanss produce a specific negative voltage, positive electricity Buffer and negative electricity Buffer drives HEMT K101 to close, and resonator cavity produces a reverse spike voltage to LED by resonance Reverse power supply, to accelerate the shut-off of LED；The resonator cavity can control the time of reverse power supply, with reality Jing after control resonant parameter Existing sequencing contro, makes resonator cavity compare with the LED turn-off times.

2. a kind of GHz high speeds LED light communications driver according to claim 1, it is characterised in that：The pressure limiting constant current list Unit includes wave filter, rectifier bridge and the circuit for power conversion being sequentially connected in series；The wave filter other end is AC input end, defeated for civil power Enter；Circuit for power conversion is entered after the filtered device filtering of civil power, rectifier bridge rectification；The circuit for power conversion is used to realize direct current Turn direct current and power and output current is limited to produce a constant pressure being adapted to needed for output, the voltage of output is Va, Vb With tri- groups of Vg.

3. a kind of GHz high speeds LED light communications driver according to claim 2, it is characterised in that：It is also whole including being connected to PFC between stream bridge and circuit for power conversion；The PFC is used for Active PFC and produces a HVDC output, with Reduce the harmonic wave to civil power to disturb.

4. a kind of GHz high speeds LED light communications driver according to claim 1, it is characterised in that：Switch K101 is high electricity Transport factor transistor.

5. a kind of GHz high speeds LED light communications driver according to claim 1 or 2 or 3 or 4, it is characterised in that：It is described Control device includes that frequency conversion engine, reference clock signal source, reference power supply, voltage controlled oscillator, compensation network, programme-control are eased up Rush device；Also include electric capacity C2；Reference clock signal source, reference power supply, voltage controlled oscillator, compensation network and programme controlled output It is connected with frequency conversion engine respectively；The output of reference power supply is also connected with programme-control, programme controlled output simultaneously also with buffering Device connects；It is used for controlling switch K101 after output series capacitance C2 of buffer.