CN105005753B - NFC communication device - Google Patents
NFC communication device Download PDFInfo
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- CN105005753B CN105005753B CN201510486362.0A CN201510486362A CN105005753B CN 105005753 B CN105005753 B CN 105005753B CN 201510486362 A CN201510486362 A CN 201510486362A CN 105005753 B CN105005753 B CN 105005753B
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Abstract
The present invention discloses a kind of NFC communication device, including receives link, modulation link, coil and signal processing apparatus；Receives link is coupled to receive the request signal that external device is sent by coil, and is transferred to signal processing means processes after request signal is demodulated；Signal processing apparatus control modulation link is coupled by coil with the coil of external device, and outwardly equipment sends answer signal corresponding with request signal；Receives link includes Schmidt's comparator, level converter and the demodulating equipment being sequentially connected in series；The other end of Schmidt's comparator is electrically connected with the first end of coil；Modulation link includes modulating device, current conversion module and the current-amplifying device being sequentially connected in series；Current conversion module is used to the voltage signal through over-modulating device being converted to current signal；Current-amplifying device is used to current signal being amplified；Other ends of current-amplifying device are electrically connected with coil.The electronic device of above-mentioned NFC communication device is less, and cost is relatively low.
Description
Technical field
The present invention relates to technical field of near field communication, more particularly to a kind of NFC communication device.
Background technology
In recent years, with the development of mobile Internet, using smart mobile phone as the mobile device of representative, because its is easy to carry,
The features such as application extension is versatile and flexible, as more and more important information interactive terminal.Mobile device is to closely interconnection technique
Demand cause NFC (Near Field Communication, close range wireless communication) technology to have found its suitable application
Platform.Using NFC technique, the data exchange between identification, mobile payment, two mobile devices easily can be quickly realized
Etc. content.The receives link of common NFC communication device is the circuit positioned at chip exterior, and receives link is located at chip exterior
Required electronic component is more, and cost is higher.
The content of the invention
Based on this, it is necessary to provide a kind of number of electronic components less NFC communication device.
A kind of NFC communication device, including receives link, modulation link, coil and signal processing apparatus；The receives link
By the coil and the request signal for being coupled to receive the external device transmission of external device coil, and the request is believed
It is transferred to the signal processing apparatus after number demodulation and is handled；The signal processing apparatus control modulation link passes through institute
The coil that coil is stated with the external device is coupled, and outwardly equipment sends answer signal corresponding with the request signal；
The receives link includes Schmidt's comparator, level converter and the demodulating equipment being sequentially connected in series；It is described to apply
The other end of close special comparator is electrically connected with the first end of the coil；
The modulation link includes modulating device, current conversion module and the current-amplifying device being sequentially connected in series；The electricity
Stream modular converter is used for the current signal that the voltage signal by the modulating device is converted to default size；The electric current is put
Big device is used to the current signal being amplified；Other ends of the current-amplifying device are electrically connected with the coil.
In one of the embodiments, the receives link also includes amplification module, and the amplification module is opened including first
Close and amplifier group；
The first switch is in parallel with the amplifier group, the first end of the first switch and the first end of the coil
Electrical connection, the second end of the first switch is electrically connected with Schmidt's comparator；
Schmidt's comparator is electrically connected by the first switch or the amplifier group and the first end of the coil
Connect.
In one of the embodiments, the amplifier group includes the amplification that an amplifier or two or more are in parallel
Device, each amplifier has a default multiplication factor scope, and each amplifier multiplication factor scope not
It is overlapping
In one of the embodiments, the receives link also by the coil receive that the external device sends when
Clock signal, and handled the signal processing apparatus is transferred to after clock signal reception；
When the modulated signal produced in the modulation antenna efficiency and the modulation link is high level, the clock signal
Amplitude diminish, under load modulating mode, the signal processing apparatus controls the amplifier group work, the amplifier group
The amplitude for the part that the amplitude of the clock signal is diminished is amplified to the range value of preset range.
In one of the embodiments, the receives link also includes the first coupled capacitor, first coupled capacitor
First end is electrically connected with the first end of the first switch, the second end of first coupled capacitor and the first end of the coil
Electrical connection；
Schmidt's comparator passes sequentially through the of the amplification module and first coupled capacitor and the coil
One end is electrically connected.
In one of the embodiments, the receives link also include current-limiting resistance, the first end of the current-limiting resistance with
The first end electrical connection of first coupled capacitor, the second end of the current-limiting resistance and the first end of the first switch are electrically connected
Connect；
Schmidt's comparator pass sequentially through the amplification module, the current-limiting resistance and first coupled capacitor with
The first end electrical connection of the coil.
In one of the embodiments, the receives link also includes clamp circuit, and Schmidt's comparator leads to successively
Cross the clamp circuit and the amplification module is electrically connected with the first end of the coil.
In one of the embodiments, the clamp circuit includes the first resistor and second resistance being in series；Described
Another termination power of one resistance, the other end ground connection of the second resistance；The resistance of the first resistor and the described second electricity
The resistance of resistance is equal.
In one of the embodiments, the current conversion module is transfer resistance；Or
The current conversion module be adjustable current array, the power supply termination power of the adjustable current array, it is described can
The controlled terminal of current array is adjusted to connect the modulating device, the output of the adjustable current array terminates the Current amplifier dress
Put.
In one of the embodiments, the current conversion module includes second switch, transfer resistance and adjustable current battle array
Row；
The transfer resistance one terminates current-amplifying device, another termination adjustable current array of the transfer resistance
Output end and the second switch first end, the power supply termination power of the adjustable current array, adjustable current battle array
The controlled terminal of row connects the modulating device, the second termination modulating device of the second switch；
When the adjustable current array works, the transfer resistance is short-circuited or the value of the transfer resistance is zero；
When the adjustable current array does not work, the transfer resistance value is first resistor value.
In one of the embodiments, the current-amplifying device is triode, the base stage of the triode and the electricity
The output end electrical connection of modular converter is flowed, the colelctor electrode of the triode is electrically connected with the first end of the coil, three pole
The emitter stage of pipe is electrically connected with the second end of the coil.
In one of the embodiments, the NFC communication device also includes the second electric capacity being in parallel with the coil.
Above-mentioned NFC communication device, receives link includes Schmidt's comparator, level converter and demodulating equipment, modulation
Link includes modulating device, current conversion module and current-amplifying device, using less electronic component, you can complete to external world
The demodulation modulation for the request signal that equipment is sent, saves cost.Further, above-mentioned NFC communication device can also be by the external world
The recovering clock signals that equipment is sent are into the reference clock signal for modulating link, and the reference clock signal is received link general
What the recovering clock signals that external device is sent came out, thus without being additionally provided reference clock, and precision is higher, error is more
It is small.
Brief description of the drawings
Fig. 1 is the electrical block diagram of NFC communication device one embodiment of the present invention；
Fig. 2 passes through reception chain for the request signal that the external device in NFC communication device one embodiment of the present invention is sent
The waveform diagram of road everywhere；
Fig. 3 modulates for the clock signal that the external device in NFC communication device one embodiment of the present invention is sent in load
The waveform diagram of lower process receives link everywhere.
Embodiment
It is logical to NFC of the present invention below in conjunction with accompanying drawing for the objects, technical solutions and advantages of the present invention are more clearly understood
The embodiment of T unit is illustrated.It should be appreciated that specific embodiment described herein is only to explain this hair
It is bright, it is not intended to limit the present invention.
Referring to Fig. 1, in one embodiment, NFC communication device of the present invention includes receives link 100, modulation link 200, line
Enclose L and signal processing apparatus 300.Receives link 100 is sent by the external device that is coupled to receive of coil L and external device coil
Request signal, and be conveyed to signal processing apparatus 300 after request signal is demodulated.Signal processing apparatus 300 controls modulation chain
Road 200 is coupled by coil L with the coil of external device, and outwardly equipment sends response letter corresponding with request signal.
Specifically, receives link 100 includes the Schmidt's comparator 130, level converter 120 and demodulation being sequentially connected in series
Device 110.The one end of Schmidt's comparator 130 is electrically connected with the input of level converter 120, and the of the other end and coil L
One end is electrically connected.
Modulation link 200 includes modulating device 210, current conversion module 220 and the current-amplifying device being sequentially connected in series
230.Current conversion module 220 is used for the modulation electricity that the modulated voltage signal through over-modulating device 210 is converted to default size
Flow signal.Current-amplifying device 230 is used to modulated current signal being amplified.One end of current-amplifying device 230 and electric current
The output end electrical connection of modular converter 220, other ends are electrically connected with coil L.
It should be understood that when receiving the request signal that external device is sent, modulation link 200 is idle, or
Say it is that modulation dynamics is zero.Now, the working condition of receives link 100 is as follows：Schmidt's comparator 130 receives coil L
Request signal be processed into the data signal of low and high level；Level converter 120 Schmidt's comparator 130 is handled after number
The data signal that word signal transacting is handled into suitable demodulating equipment 110；After demodulating equipment 110 handles level converter 120
Digital demodulation signal go out external device transmission information.
After the request signal of external device transmission has been received, the control modulation link 200 of signal processing apparatus 300 starts work
Make：Modulating device 210 exports modulated voltage signal according to the control of signal processing apparatus 300；Current conversion module 220 will be modulated
The modulated voltage signal that device 210 is sent is converted into modulated current signal；Current-amplifying device 230 amplifies modulated current signal
After generate modulation intelligence, coupled by coil L with the coil of external device, modulation intelligence passed into external device.
Above-mentioned NFC communication device, receives link 100 includes Schmidt's comparator 130, level converter 120 and demodulation
Device 110, modulation link 200 includes modulating device 210, current conversion module 220 and current-amplifying device 230, using less
Electronic component, you can complete to external world equipment send request signal demodulation modulation, save cost.
In the present embodiment, Schmidt's comparator 130, level converter 120 and demodulating equipment 110 are respectively positioned on NFC communication
In device chip, modulating device 210, current conversion module 220 also are located in NFC communication device chip.
It should be understood that the signal amplitude that sends of the external devices that receive of coil L is general than larger, therefore can will be outside
The signal that boundary's equipment is sent passes straight through to Schmidt's comparator 130.And the signal width that the external device received for coil L is sent
Less situation is spent, then needs to be resent to Schmidt's comparator 130 after being amplified signal.Therefore, receives link 100 may be used also
With including amplification module 150.Specifically, amplification module 150 includes first switch S1 and amplifier group 151.Wherein, first switch
S1 is in parallel with amplifier group 151, and first switch S1 first end is electrically connected with coil L first end, and the second of first switch S1
End is electrically connected with Schmidt's comparator 130.Schmidt's comparator 130 passes through first switch S1's or amplifier group 150 and coil L
First end is electrically connected.
In one embodiment, amplifier group 151 includes two amplifiers parallel with one another, such as the first amplifier O1 and the
Two amplifier O2.First amplifier O1 and the second amplifier O2 are respectively provided with a default multiplication factor scope, and the first amplification
Device O1 and the second amplifier O2 multiplication factor scope is not overlapping.It is preferred that, the first amplifier O1 is the larger height of multiplication factor
Gain amplifier, the second amplifier O2 is the less low gain amplifier of multiplication factor.So, first switch S1, the first amplification
Device O1 and the second amplifier O2 three constitute a structure to signal with straight-through, low gain amplification or plus and blowup.When
So, the first amplifier O1 and the second amplifier O2 can have several gears to be adjusted, so that first switch S1,
Gain amplifier or straight-through with larger adjustable range of the structure that one amplifier O1 and the second amplifier O2 is constituted to signal.When
So, in other embodiments, amplifier group 151 can also include an amplifier or two or more amplifier parallel with one another.
In one embodiment, receives link 100 can also include the first coupled capacitor C1.First coupled capacitor C1 and amplification
Module 150 is connected.Specifically, the first coupled capacitor C1 first end is electrically connected with first switch S1 first end, the first coupling
Electric capacity C1 the second end is electrically connected with coil L first end.Therefore, Schmidt's comparator 130 passes sequentially through the He of amplification module 150
First coupled capacitor C1 is electrically connected with coil L first end.First coupled capacitor C1 is set, be may be such that by the first coupled capacitor
C1 forceful electric power signal and weak electric signal isolation, and the path of high-frequency signal is provided, prevent power current from entering weak electricity system, to protect
Demonstrate,prove the safe handling of equipment.
In one embodiment, it is contemplated that when the amplitude for the signal that the external device that coil L is received is sent is excessive, can produce
Raw larger electric current flows into receives link 100, it is possible to which each part of receives link 100 is caused to damage.Therefore, connect
Current-limiting resistance R1 can also be included by receiving link 100.Current-limiting resistance R1 is in series with the first coupled capacitor C1 and amplification module 150.
Current-limiting resistance R1 first end is electrically connected with the first coupled capacitor C1 first end, current-limiting resistance R1 the second end and first switch
S1 first end electrical connection.Schmidt's comparator 130 passes sequentially through amplification module 150, current-limiting resistance R1 and the first coupled capacitor
C1 is electrically connected with coil L first end.I/O module is well known to those skilled in the art, and to simplify explanation, I/O module is not in reality
Show in example.
It is preferred that, receives link 100 also includes clamp circuit 140.Schmidt's comparator 130 passes sequentially through clamp circuit
140 and amplification module 150 electrically connected with coil L first end.Specifically, clamp circuit 140 can include first be in series
Resistance R2 and second resistance R3.First resistor R2 another termination power, second resistance R3 other end ground connection.First resistor R2
Resistance it is equal with second resistance R3 resistance.Clamp circuit 140 is set, can be by clamp circuit 140 by signal amplitude
Center value is arranged to the half numerical value of the supply voltage of clamp circuit 140.Certainly, clamp circuit 140 can also be other circuit knots
Structure, due to the technology that clamp circuit is well known to those skilled in the art, therefore will not be repeated here.
In one embodiment, current conversion module 220 can be transfer resistance R4, transfer resistance R4 two ends respectively with tune
Device 210 and current-amplifying device 230 processed are electrically connected.Under this scheme, the modulated voltage signal sent by modulating device 210 is passed through
After transfer resistance R4, modulated current signal is converted to.Transfer resistance R4 can be the resistance of fixed resistance value, or resistance is big
Small adjustable resistance.Transfer resistance R4 resistance can be any resistance between tens kilo-ohms to hundreds of kilo-ohms.
In addition, current conversion module 220 can also be adjustable current array 221.The power supply termination of adjustable current array 221
Power supply, the controlled terminal of adjustable current array 221 connects modulating device 210, the output termination Current amplifier of adjustable current array 221
Device 230.Under this scheme, adjustable current array 221 is set to suitable current value, the tune sent by modulating device 210
Voltage signal processed is converted to modulated current signal after adjustable current array 221.
In one embodiment, current conversion module 220 can also include second switch S2, transfer resistance R4 and adjustable current
Array 221.The converted resistance R4 of modulated voltage signal or adjustable current array 221 that modulation module 210 is sent, are converted into tune
Current signal processed.Specifically, the circuit structure of current conversion module 220 can be：The termination Current amplifier dresses of transfer resistance R4 mono-
Put 230, the output end and second switch S2 first end of transfer resistance R4 another termination adjustable current array 221.Adjustable electric
Flow the power supply termination power of array 221, the controlled terminal of adjustable current array 221 connects modulating device 210, the of second switch S2
Two termination modulating devices 210.When adjustable current array 221 works, second switch S2 open, and transfer resistance R4 be short-circuited or
Transfer resistance R4 resistance is zero.When adjustable current array 221 does not work, second switch S2 closures, transfer resistance R4's takes
It is worth for first resistor value, first resistor value can be any resistance between tens kilo-ohms to hundreds of kilo-ohms.In this scheme, conversion electricity
It can be the adjustable resistance of resistance size to hinder R4.
It should be understood that in other embodiments, the circuit structure of current conversion module 220 can also be：Transfer resistance
R4 connects with second switch S2, and the transfer resistance R4 and second switch S2 after series connection are that adjustable current array 221 is in parallel, series connection
Transfer resistance R4 and second switch S2 two ends afterwards is electrically connected with the controlled terminal and output end of adjustable current array respectively.This
When, transfer resistance can be the resistance or the adjustable resistance of resistance size of fixed resistance value.Transfer resistance R4 resistance can be tens
Kilo-ohm to any resistance between hundreds of kilo-ohms.
In one embodiment, current-amplifying device 230 is triode Q.The output end and triode of current conversion module 220
Q base stage electrical connection.Triode Q colelctor electrode is electrically connected with coil L first end, and the of triode Q emitter stage and coil L
Two ends are electrically connected.Triode Q is used for the voltage amplitude in modulation coil L after modulated current signal is amplified.Certainly, in other realities
Apply in example, current-amplifying device 230 can also can amplify the device of electric current for other, and triode Q cost is relatively low.
It should be understood that during modulation link 200 works, modulation link 200 needs a reference clock.And
When modulating the work of link 200, the coil of external device still sends signal by being coupled with coil L to receives link 100.Cause
This, can revert to modulation chain by receives link 100 by when modulation link 200 works by the signal that external device is sent
Reference clock needed for road 200, without the reference clock signal needed for extra increase modulation link 200.
Specifically, receives link 100 also receives the clock signal that external device is sent by coil L, and by clock signal
Signal processing apparatus 300 is sent to after processing.The modulated signal for working and modulating the generation of link 200 in modulation link 200 is height
During level, the amplitude of the clock signal after being coupled in the presence of load modulation can be pulled low, and signal processing apparatus 300 can be controlled
Amplifier group 151 works.The amplitude for the part that amplifier group 151 diminishes the amplitude of clock signal is amplified to the width of preset range
Angle value.Specifically, amplifier group 151 can only to being pulled low after clock signal amplitude be pulled low part amplification, also may be used
It is amplified with the entirety of the clock signal after to being pulled low.Because the reference clock signal is received link by external device
What the signal of transmission was recovered, thus without being additionally provided reference clock, and precision is higher, error is smaller.
In the present embodiment, transfer resistance R4 resistance can not be excessive or too small, if transfer resistance R4 resistance is excessive, adjusts
The modulation depth of link 200 processed is too small, and modulation link 200 may not have modulating action；If transfer resistance R4 resistance is too small,
Then the modulation depth of modulation link 200 is too big, may influence the recovery of reference clock.Specifically, transfer resistance R4 resistance
It can be chosen between tens kilo-ohms to hundreds of kilo-ohms.Certainly, transfer resistance R4 resistance is also with triode Q multiplication factor and putting
The multiplication factor of big device group 151 is related.Therefore, the span of above-mentioned transfer resistance R4 resistances is a recommended value, specifically
Value can enter line translation according to practical situations.
In the present embodiment, part beyond the first coupled capacitor C1 and current-limiting resistance R1 is removed in receives link 100 can be with
It is respectively positioned in NFC communication device chip, the portion beyond current-amplifying device 230 and transfer resistance R4 is removed in modulation link 200
Dividing can be respectively positioned in NFC communication device chip.
In one embodiment, NFC communication device also includes the second electric capacity C2 being in parallel with coil L.It is suitable by selection
Coil model, that is, inductance value size, and suitable second capacitance size, resonance point can be adjusted to NFC
Working frequency (such as 13.56MHz) near, thus with more preferable selecting frequency characteristic, between coil L and the coil of external equipment
Coupling effect more preferably, signal transmission is more preferable.
Referring to Fig. 1, Fig. 2 and Fig. 3, structure and workflow to NFC communication device of the present invention are carried out furtherly
It is bright.
Referring to Fig. 1, receives link 100 includes the first coupled capacitor C1, current-limiting resistance R1, the amplification module being sequentially connected in series
150th, clamp circuit 140, Schmidt's comparator 130, level converter 120 and demodulating equipment 110.Wherein, amplification module 150
Including the first switch S1, the first amplifier O1 and the second amplifier O2 being in parallel.What clamp circuit 140 was in series including two
First resistor R2 and second resistance R3.Level converter 120 can be level translator.Demodulating equipment 110 can be demodulation
Device.First coupled capacitor C1 first end is electrically connected with current-limiting resistance R1.
Modulation link 200 includes triode Q, current-amplifying device 220 and the modulating device 210 being sequentially connected in series.Wherein, it is electric
Flowing amplifying device 220 includes transfer resistance R4, second switch S2 and adjustable current array 221.Transfer resistance R4 mono- terminates electric current
Amplifying device 230, the output end and second switch S2 first end of transfer resistance R4 another termination adjustable current array 221.
The power supply termination power of adjustable current array 221, the controlled terminal of adjustable current array 221 connects modulating device 210, second switch
S2 the second termination modulating device 210.
Coil L two ends are parallel with the second electric capacity C2.Coil L first end and the first coupled capacitor C1 other end and three
Pole pipe Q colelctor electrode electrical connection, coil L the second end is electrically connected with triode Q emitter stage, and coil L the second end ground connection.
The other end of demodulating equipment 110 is electrically connected with signal processing apparatus 300.The other end and signal processing apparatus of modulating device 210
300 electrical connections.According to contactless specification, different types of interface traffic channel is different, with A classes in the present embodiment
Exemplified by ASK (Amplitude Shift Keying, amplitude-shift keying) 100% is modulated, to illustrate the work(of NFC communication device of the present invention
Energy and advantage.In A class ASK100% modulated process, be carried out by " pause " state PCD (proximity Coupling device) and
Communication between PICC (proximity card), " pause " state can be understood as the envelope monotone decreasing of PCD to less than at the beginning of it
5% part of initial value is interval.
Referring to Fig. 2, in the radiofrequency field that PICC is placed in PCD read write lines, now the coil of PCD read write lines is close with coil L,
The request signal waveform that PCD read write lines are sent is shown in Fig. 2 A1 waveforms.Coil L will receive the request of PCD read write lines transmission
Signal is sent to receives link 100, after the first coupled capacitor C1, current-limiting resistance R1 and first switch S1, the signal of formation
As shown in B1 waveforms.Because the first switch S1 of amplification module 150 works, and amplifier group 151 does not work, therefore B1 waveforms
Amplitude does not change with respect to the amplitude of A1 waveforms.Certainly, if selection amplifier group 151 works, first switch S1 does not work,
Then the amplitude of B1 waveforms can change with respect to the amplitude of A1 waveforms.B1 waveform signals pass through clamp circuit 140, due to clamp electricity
Road 140 includes the equal first resistor R2 and second resistance R3 of two resistances, therefore the numerical value of the central point of B1 wave-shape amplitudes is
The supply voltage V of clamp circuit 140DDThe half of numerical value.And Schmidt's comparator 130 can will be above the signal of predetermined threshold value voltage
High level is placed in, the signal less than predetermined threshold value voltage is placed in low level, therefore B1 waveform signals are by clamp circuit 140 and apply
After close special comparator 130, the signal of formation is as shown in C1 waveforms.Because the operating voltage of demodulating equipment 110 is 1.2V, and C1 ripples
The high level of shape signal is 3.3V, therefore the high level of C1 waveform signals need to be converted into 1.2V using level converter 120.
After signal after the switching levels of level converter 120 is demodulated by demodulating equipment 110, signal processing apparatus 300 is sent to.
Modulating device 210 exports modulated signal CLKm according to the control of signal processing apparatus 300, now modulated signal CLKm
For modulated voltage signal, modulated signal CLKm can be modulated by following two modes.A kind of mode is that closing is adjustable
Current array 221, second switch S2 closures, by second switch S2 and transfer resistance R4, modulated voltage signal CLKm is changed
For modulated current signal.Now, transfer resistance R4 has certain resistance.Another way is to disconnect second switch S2, will be changed
Resistance R4 sets to zero resistance or by transfer resistance R4 short circuits, and adjustable current array 221 is set into suitable current value, passes through
Modulated voltage signal CLKm is converted to modulated current signal by adjustable current array 221.Then electric current will be modulated by triode Q
Signal is amplified.
, it is necessary to which PICC replys answer signal after the signal of PCD read write lines transmission is received, and modulation is not exported in PICC
During signal, PCD read write lines can continue to send 13.56MHz clock signal, and the clock signal can be with after receives link 100
Used as the reference clock of modulation link 200.Referring to Fig. 3, when modulated signal CLKm is high level, coil L is received
The amplitude of clock signal for the 13.56MHz that PCD read write lines are sent can be pulled low, the clock signal after dragging down as shown in A2, and by
Clock signal A2 after dragging down is inaccurate as the reference clock of modulation link 200.In the present embodiment, signal processing apparatus
300 detect after the clock signal A2 after being pulled low, and control amplifier group 151 works, the clock signal A2's after being pulled low
The part that amplitude is pulled low is amplified to the range value of preset range, as shown in B2.Signal B2 passes through clamp circuit 140 and Schmidt
After comparator 130, the signal of generation is as shown in C2., can and signal C2 meets the requirement of the reference clock signal of modulation link 200
Used using the reference clock signal as modulation link 200.
It should be noted that signal processing apparatus 300 can control amplifier group 151 to be worked with suitable gain, will be by
The part that the amplitude of clock signal A2 after dragging down is pulled low is amplified to the range value of preset range.And for being pulled low after when
The part that clock signal A2 amplitude is not pulled low, then no requirement (NR).I.e. amplifier group 151 can only to being pulled low after clock signal
The amplification of part that A2 amplitude is pulled low, can also to being pulled low after clock signal A2 be integrally amplified.
Above-mentioned NFC communication device, using less electronic component, you can complete the request signal that equipment is sent to external world
Demodulation is modulated, and saves cost.In addition, receives link 100 can also be sent out external device when modulating the work of link 200
The clock signal sent carries out recovery processing, ultimately generates the reference clock signal of modulation link 200, without extra increase
The reference clock signal needed for link 200 is modulated, and because the reference clock signal is that received link 100 sends out external device
What the signal sent was recovered, therefore without being additionally provided reference clock, and precision is higher, error is smaller.
Embodiment described above only expresses the several embodiments of the present invention, and it describes more specific and detailed, but simultaneously
Therefore the limitation to the scope of the claims of the present invention can not be interpreted as.It should be pointed out that for one of ordinary skill in the art
For, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to the guarantor of the present invention
Protect scope.Therefore, the protection domain of patent of the present invention should be determined by the appended claims.
Claims (12)
1. a kind of NFC communication device, it is characterised in that including receives link, modulation link, coil and signal processing apparatus；Institute
Receives link is stated by the coil and the request signal for being coupled to receive the external device transmission of external device coil, and will
The signal processing apparatus is transferred to after the request signal demodulation to be handled；The signal processing apparatus controls the modulation
Link is coupled by the coil with the coil of the external device, sends corresponding with the request signal to the external device
Answer signal；
The receives link includes Schmidt's comparator, level converter and the demodulating equipment being sequentially connected in series；The Schmidt
The other end of comparator is electrically connected with the first end of the coil；
The modulation link includes modulating device, current conversion module and the current-amplifying device being sequentially connected in series；The electric current turns
Mold changing block is used for the modulated current signal that the modulated voltage signal by the modulating device is converted to default size；The electricity
Stream amplifying device is used to the current signal being amplified；Other ends of the current-amplifying device are electrically connected with the coil
Connect.
2. NFC communication device according to claim 1, it is characterised in that the receives link also includes amplification module, institute
Stating amplification module includes first switch and amplifier group；
The first switch is in parallel with the amplifier group, and the first end of the first switch and the first end of the coil are electrically connected
Connect, the second end of the first switch is electrically connected with Schmidt's comparator；
Schmidt's comparator is electrically connected by the first switch or the amplifier group with the first end of the coil.
3. NFC communication device according to claim 2, it is characterised in that the amplifier group include an amplifier or
The amplifier that two or more is in parallel, each amplifier has a default multiplication factor scope, and is put described in each
The multiplication factor scope of big device is not overlapping.
4. NFC communication device according to claim 2, it is characterised in that the receives link is also connect by the coil
The clock signal that the external device is sent is received, and the signal processing apparatus will be transferred to after clock signal processing；
When the modulated signal produced in the modulation antenna efficiency and the modulation link is high level, the width of the clock signal
Degree diminishes, under load modulating mode, and the signal processing apparatus controls the amplifier group work, and the amplifier group is by institute
The amplitude for stating the part that the amplitude of clock signal diminishes is amplified to the range value of preset range.
5. NFC communication device according to claim 2, it is characterised in that the receives link also includes the first coupling electricity
Hold, the first end of first coupled capacitor electrically connects with the first end of the first switch, the of first coupled capacitor
Two ends are electrically connected with the first end of the coil；
Schmidt's comparator passes sequentially through the amplification module and first coupled capacitor and the first end of the coil
Electrical connection.
6. NFC communication device according to claim 5, it is characterised in that the receives link also includes current-limiting resistance, institute
The first end for stating current-limiting resistance is electrically connected with the first end of first coupled capacitor, the second end of the current-limiting resistance with it is described
The first end electrical connection of first switch；
Schmidt's comparator pass sequentially through the amplification module, the current-limiting resistance and first coupled capacitor with it is described
The first end electrical connection of coil.
7. NFC communication device according to claim 2, it is characterised in that the receives link also includes clamp circuit, institute
State that Schmidt's comparator passes sequentially through the clamp circuit and the amplification module is electrically connected with the first end of the coil.
8. NFC communication device according to claim 7, it is characterised in that the clamp circuit includes first be in series
Resistance and second resistance；Another termination power of the first resistor, the other end ground connection of the second resistance；First electricity
The resistance of resistance is equal with the resistance of the second resistance.
9. NFC communication device according to claim 1, it is characterised in that the current conversion module is transfer resistance；Or
The current conversion module is adjustable current array, the power supply termination power of the adjustable current array, the adjustable electric
The controlled terminal of stream array connects the modulating device, and the output of the adjustable current array terminates the current-amplifying device.
10. NFC communication device according to claim 1, it is characterised in that the current conversion module is opened including second
Pass, transfer resistance and adjustable current array；
The transfer resistance one terminates the current-amplifying device, another termination adjustable current array of the transfer resistance
Output end and the second switch first end, the power supply termination power of the adjustable current array, adjustable current battle array
The controlled terminal of row connects the modulating device, the second termination modulating device of the second switch；
When the adjustable current array works, the transfer resistance is short-circuited or the value of the transfer resistance is zero；Institute
When stating adjustable current array and not working, the transfer resistance value is first resistor value.
11. NFC communication device according to claim 1, it is characterised in that the current-amplifying device is triode, institute
The base stage for stating triode is electrically connected with the output end of the current conversion module, the colelctor electrode of the triode and the coil
First end is electrically connected, and the emitter stage of the triode is electrically connected with the second end of the coil.
12. the NFC communication device according to claim 1 to 11 any one, it is characterised in that the NFC communication device
Also include the second electric capacity being in parallel with the coil.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100291869A1 (en) * | 2007-11-15 | 2010-11-18 | Robin Wilson | Near field rf communicators |
| CN101964065A (en) * | 2009-07-23 | 2011-02-02 | 北京同方微电子有限公司 | Radio frequency integrated circuit for near-field communication |
| CN102446286A (en) * | 2010-10-12 | 2012-05-09 | 上海华虹Nec电子有限公司 | ASK (Amplitude Shift Keying) demodulator of RFID (Radio Frequency Identification) label analog front-end circuit |
| US20140237206A1 (en) * | 2012-06-30 | 2014-08-21 | At&T Intellectual Property I, L.P. | Managing Personal Information on a Network |
| WO2015109267A1 (en) * | 2014-01-17 | 2015-07-23 | Hallmark Cards, Incorporated | System and method for near field communication |
| CN204856521U (en) * | 2015-08-03 | 2015-12-09 | 珠海市杰理科技有限公司 | NFC communication device |
-
2015
- 2015-08-03 CN CN201510486362.0A patent/CN105005753B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100291869A1 (en) * | 2007-11-15 | 2010-11-18 | Robin Wilson | Near field rf communicators |
| CN101964065A (en) * | 2009-07-23 | 2011-02-02 | 北京同方微电子有限公司 | Radio frequency integrated circuit for near-field communication |
| CN102446286A (en) * | 2010-10-12 | 2012-05-09 | 上海华虹Nec电子有限公司 | ASK (Amplitude Shift Keying) demodulator of RFID (Radio Frequency Identification) label analog front-end circuit |
| US20140237206A1 (en) * | 2012-06-30 | 2014-08-21 | At&T Intellectual Property I, L.P. | Managing Personal Information on a Network |
| WO2015109267A1 (en) * | 2014-01-17 | 2015-07-23 | Hallmark Cards, Incorporated | System and method for near field communication |
| CN204856521U (en) * | 2015-08-03 | 2015-12-09 | 珠海市杰理科技有限公司 | NFC communication device |
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