CN107508662A - A kind of clock recovery circuitry and method - Google Patents
A kind of clock recovery circuitry and method Download PDFInfo
- Publication number
- CN107508662A CN107508662A CN201710867796.4A CN201710867796A CN107508662A CN 107508662 A CN107508662 A CN 107508662A CN 201710867796 A CN201710867796 A CN 201710867796A CN 107508662 A CN107508662 A CN 107508662A
- Authority
- CN
- China
- Prior art keywords
- data
- clock
- sampling
- circuit
- phase clock
- 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.)
- Pending
Links
- 238000011084 recovery Methods 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 24
- 238000005070 sampling Methods 0.000 claims abstract description 132
- 230000005540 biological transmission Effects 0.000 claims description 11
- 102100038026 DNA fragmentation factor subunit alpha Human genes 0.000 description 4
- 101000950906 Homo sapiens DNA fragmentation factor subunit alpha Proteins 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 230000001360 synchronised effect Effects 0.000 description 3
- 102100038023 DNA fragmentation factor subunit beta Human genes 0.000 description 2
- 241001269238 Data Species 0.000 description 2
- 101100277639 Homo sapiens DFFB gene Proteins 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L7/00—Arrangements for synchronising receiver with transmitter
- H04L7/02—Speed or phase control by the received code signals, the signals containing no special synchronisation information
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L7/00—Arrangements for synchronising receiver with transmitter
- H04L7/02—Speed or phase control by the received code signals, the signals containing no special synchronisation information
- H04L7/033—Speed or phase control by the received code signals, the signals containing no special synchronisation information using the transitions of the received signal to control the phase of the synchronising-signal-generating means, e.g. using a phase-locked loop
Abstract
The invention provides a kind of clock recovery circuitry and method, the present invention when selecting optimal phase clock every time, it is that an optimal phase clock is selected from all phase clocks, an optimal phase clock is not selected using of the prior art among last non-selected phase clock, and then can be when selecting optimal phase clock every time, the serial data received can be quickly and accurately sampled using optimal phase clock, reduces the probability of serial data sampling failure.
Description
Technical field
The present invention relates to high-speed serial data transmission field, in particular, is related to a kind of clock recovery circuitry and method.
Background technology
USB2.0 high-speed serial datas Transmission system includes transtation mission circuit and receiving circuit, and USB2.0 high-speed serial datas pass
It is defeated not transmit data sync clock and data together, thus need to use local clock in receiving terminal and receive serial
Data recovery goes out synchronised clock and is used for sampling and synchronous serial data.
The method that currently used high speed data clock recovers is space over-sampling method, usually using N number of adjacent phase
Identical and frequency is spaced with data transfer rate identical with frequency clock Simultaneous Sampling Data, processing is carried out to the data sampled and found out
Optimal phase clock, when using space oversampler method, optimal phase clock is selected, and use the phase selected
Bit clock goes the process of sampling serial data to include：
When an optimal phase clock is selected from all phase clocks first, and then using the phase selected
Clock goes the serial data that sampling receives, and hereafter, an optimal phase clock is selected from remaining phase clock, using new
The phase clock selected goes to continue the serial data that sampling receives.
When the phase clock of first time selection is still better than the phase clock selected for the second time, now selected using second
The phase clock selected out continues the serial data that sampling receives, and is likely to result in the failure of part-serial data sampling.
The content of the invention
In view of this, the present invention provides a kind of clock recovery circuitry and method, to solve when the phase of first time selection
Clock is still better than the phase clock selected for the second time, now continues what sampling received using the phase clock selected for the second time
Serial data, it is likely to result in the problem of part-serial data sampling fails.
In order to solve the above technical problems, present invention employs following technical scheme：
A kind of clock recovery circuitry, including：
Over-sampling and edge sense circuit, edge count and ballot selection circuit, clock selection circuit；
The over-sampling and edge sense circuit, the edge count and ballot selection circuit, the clock selection circuit
It is sequentially connected；
The over-sampling and edge sense circuit, for selected every time from all phase clocks one it is optimal
During phase clock, using N number of phase clock while sampling serial data, determined according to the sampled result of two neighboring phase clock
Data jump is along position；Wherein, N is positive integer and N is not less than 2；
The edge counts and ballot selection circuit, for according to data jump edge of each data jump along position
Number, the number that a corresponding data jump reaches along number default value at first is selected along position from all data jumps
According to hopping edge position, and by the data jump of selection the clock selection circuit is sent to along position；
The clock selection circuit, for the data jump according to reception along position, selected from N number of phase clock
Go out an optimal phase clock, so that data sampling and string turn and circuit is described serial according to the phase clock sampling selected
Data.
Preferably, the over-sampling and edge sense circuit are used to be determined according to the sampled result of two neighboring phase clock
When data jump is along position, it is specifically used for：
By the sampled result XOR of two neighboring phase clock, the position of data edge is obtained.
Preferably, the edge counts and ballot selection circuit is used for according to data jump of each data jump along position
Along number, a corresponding data jump is selected along position from all data jumps and reaches default value at first along number
Data jump along position when, be specifically used for：
The data jump of real-time statistics different pieces of information hopping edge position is along number；
A corresponding data jump is selected along position from all data jumps and reaches present count at first along number
The data jump of value is along position.
Preferably, the clock selection circuit is used for the data jump according to reception along position, from N number of phase clock
In select an optimal phase clock so that data sampling and string turn and circuit according to select phase clock sampling institute
When stating serial data, it is specifically used for：
According to default data jump along position and the corresponding relation of phase clock, it is determined that with the data jump of reception along position
Corresponding phase clock is put, so that data sampling and string turn and circuit samples the serial number according to the phase clock selected
According to.
Preferably, in addition to：
Data Matching circuit；The Data Matching circuit turns with the data sampling and string and circuit is connected；
The Data Matching circuit, for match be input to the serial data of the over-sampling and edge sense circuit with it is defeated
Enter to the data sampling and string to turn the transmission delay of the simultaneously serial data of circuit, to ensure that data sampling and string turn and in circuit
The institute inputted in data, the relativeness of recovered clock and over-sampling and edge sense circuit in the serial data of input
State the data in serial data, the relativeness of phase clock corresponding with the recovered clock in the serial data keeps one
Cause.
A kind of clock recovery method, including：
Over-sampling and edge sense circuit are selecting an optimal phase clock from all phase clocks every time
When, using N number of phase clock while sampling serial data, data jump is determined according to the sampled result of two neighboring phase clock
Along position；Wherein, N is positive integer and N is not less than 2；
Edge count and ballot selection circuit according to data jump of each data jump along position along number, from all
Data jump selects a corresponding data jump along position and reaches the data jump of default value at first along number along position
Put, and the data jump of selection is sent to clock selection circuit along position；
Clock selection circuit, along position, selects one most according to the data jump of reception from N number of phase clock
Excellent phase clock, so that data sampling and string turn and circuit samples the serial data according to the phase clock selected.
Preferably, over-sampling and edge sense circuit determine data jump according to the sampled result of two neighboring phase clock
Along position, including：
By the sampled result XOR of two neighboring phase clock, the position of data edge is obtained.
Preferably, edge count and ballot selection circuit according to data jump of each data jump along position along number,
The data that a corresponding data jump reaches along number default value at first are selected along position from all data jumps
Hopping edge position, including：
The data jump of real-time statistics different pieces of information hopping edge position is along number；
A corresponding data jump is selected along position from all data jumps and reaches present count at first along number
The data jump of value is along position.
Preferably, clock selection circuit is selected according to the data jump of reception along position from N number of phase clock
One optimal phase clock, so that data sampling and string turn and circuit samples the serial number according to the phase clock selected
According to when, be specifically used for：
According to default data jump along position and the corresponding relation of phase clock, it is determined that with the data jump of reception along position
Corresponding phase clock is put, so that data sampling and string turn and circuit samples the serial number according to the phase clock selected
According to.
Preferably, over-sampling and edge sense circuit are selecting an optimal phase from all phase clocks every time
During bit clock, using N number of phase clock while sampling serial data, number is determined according to the sampled result of two neighboring phase clock
Before the position of hopping edge, in addition to：
The Data Matching Circuit Matching is input to the serial data of the over-sampling and edge sense circuit with being input to
The data sampling and string turn and the transmission delay of the serial data of circuit, to ensure to input in data sampling and string turn and circuit
The serial data in data, the string that inputs in the relativeness of recovered clock and over-sampling and edge sense circuit
Data, the relativeness of phase clock corresponding with the recovered clock in the serial data in row data are consistent.
Compared to prior art, the invention has the advantages that：
It is of the invention when selecting optimal phase clock every time the invention provides a kind of clock recovery circuitry and method,
It is that an optimal phase clock is selected from all phase clocks, not using of the prior art from last unselected
An optimal phase clock is selected among the phase clock selected, and then ought can every time select optimal phase clock
When, the serial data received can be quickly and accurately sampled using optimal phase clock, reduces serial data sampling failure
Probability.
Brief description of the drawings
In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing
There is the required accompanying drawing used in technology description to be briefly described, it should be apparent that, drawings in the following description are only this
The embodiment of invention, for those of ordinary skill in the art, on the premise of not paying creative work, can also basis
The accompanying drawing of offer obtains other accompanying drawings.
Fig. 1 is a kind of structural representation of clock recovery circuitry provided by the invention；
Fig. 2 is the structural representation of a kind of over-sampling provided by the invention and edge sense circuit；
Fig. 3 is the structural representation of a kind of edge counting provided by the invention and ballot selection circuit；
Fig. 4 is a kind of structural representation for counting and voting circuit provided by the invention；
Fig. 5 is a kind of structural representation of clock selection circuit provided by the invention；
Fig. 6 is a kind of data sampling provided by the invention and string turns and the structural representation of circuit；
Fig. 7 is a kind of method flow diagram of clock recovery method provided by the invention.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete
Site preparation describes, it is clear that described embodiment is only part of the embodiment of the present invention, rather than whole embodiments.It is based on
Embodiment in the present invention, those of ordinary skill in the art are obtained every other under the premise of creative work is not made
Embodiment, belong to the scope of protection of the invention.
The embodiments of the invention provide a kind of clock recovery circuitry, reference picture 1, including：
Over-sampling and edge sense circuit 101, edge count and ballot selection circuit 103, clock selection circuit 104.
Over-sampling and edge sense circuit 101, edge count and voted selection circuit 103, clock selection circuit 104 successively
Connection, N number of phase clock 102 is counted with over-sampling and edge sense circuit 101, edge and ballot selection circuit 103, clock select
Select that circuit 104 connects respectively, N is that positive integer and N are not less than 2, it is preferred that N 6.
Each phase clock in N number of phase clock 102, for providing clock signal to over-sampling and edge sense circuit
101st, edge counting and ballot selection circuit 103, clock selection circuit 104；
Over-sampling and edge sense circuit 101, for selected every time from all phase clocks one it is optimal
During phase clock, using N number of phase clock while sampling serial data, determined according to the sampled result of two neighboring phase clock
Data jump is along position；
Edge counts and ballot selection circuit 103, for according to data jump of each data jump along position along number,
The data that a corresponding data jump reaches along number default value at first are selected along position from all data jumps
Hopping edge position, and the data jump of selection is sent to the clock selection circuit along position；Wherein, default value is technology
What personnel set in advance.
Clock selection circuit 104, for the data jump according to reception along position, selected from N number of phase clock
Go out an optimal phase clock, so that data sampling and string turn and circuit 105 is according to the phase clock sampling selected
Serial data.
Optionally, on the basis of the present embodiment, in addition to：
Data Matching circuit 106；Data Matching circuit 106 turns with data sampling and string and circuit 105 is connected；
Data Matching circuit 106, for match be input to the serial data of the over-sampling and edge sense circuit 101 with
It is input to the data sampling and string turns the transmission delay that the serial data of simultaneously circuit 105 is come due to transmission path different band, with
Ensure data sampling and string turns and the data in circuit 105 in the serial data that inputs, the relativeness of recovered clock with
Data in the serial data inputted in over-sampling and edge sense circuit 101, with recovery in the serial data when
The relativeness of phase clock corresponding to clock is consistent.
Specifically, the course of work of above-mentioned each circuit is：
The data of input are serial data, and serial data is divided into two-way, all the way as clock recovery, be input to over-sampling and
In edge sense circuit 101, sample, be input in Data Matching circuit 106 as recovered clock all the way.The purpose of clock recovery
Phase clock is to determine, the purpose of recovered clock sampling is to carry out data sampling to serial data using the phase clock of determination to obtain
To the data synchronous with phase clock.
When 6 phase clocks are the equal 480M in adjacent phase interval caused by phaselocked loop (local crystal oscillator clock makes reference)
Clock.
After over-sampling and edge sense circuit 101 receive serial data, N number of phase clock while sampling serial number are used
According to determining data jump along position according to the sampled result of two neighboring phase clock, edge counts and ballot selection circuit 103
According to data jump of each data jump along position along number, a correspondence is selected along position from all data jumps
Data jump reach the data jump of default value at first along number and sent along position, and by the data jump of selection along position
To clock selection circuit 104, clock selection circuit 104, along position, selects according to the data jump of reception from N number of phase clock
Go out an optimal phase clock, data sampling and string turn and circuit 105 uses the phase clock sampling serial data selected out.
Data Matching circuit 106 matches serial data and the input for being input to the over-sampling and edge sense circuit 101
Turn to the data sampling and string and the serial data of circuit 105 is due to the next transmission delay of transmission path different band, to ensure
Data, the relativeness of recovered clock in the serial data that data sampling and string turn and inputted in circuit 105 are adopted with crossing
The recovered clock pair in data and the serial data in the serial data inputted in sample and edge sense circuit 105
The relativeness for the phase clock answered is consistent.
It is that one is selected from all phase clocks when selecting optimal phase clock every time in the present embodiment
Optimal phase clock, it is not optimal using selecting one among the phase clock non-selected from the last time of the prior art
Phase clock, and then when selecting optimal phase clock every time optimal phase clock can be used accurately fast
The serial data that the sampling of speed receives, reduce the probability of serial data sampling failure.
Optionally, on the basis of any of the above-described embodiment, over-sampling and edge sense circuit are used for according to two neighboring
When the sampled result of phase clock determines data jump along position, it is specifically used for：
By the sampled result XOR of two neighboring phase clock, the position of data edge is obtained.
Specifically, the circuit structure diagram reference picture 2 of over-sampling and edge sense circuit.
In Fig. 2, over-sampling and edge sense circuit include multiple triggers (trigger 1010- triggers 10211) and more
Individual XOR gate (XOR gate 1020- XOR gates 1025).
Wherein, the present embodiment is by taking 6 phase clocks as an example, and the frequency of 6 phase clocks is identical, between adjacent phase clock
Interval be identical, be a clock cycle 1/6,6 phase clocks frequency with input serial data maximum
Data transfer rate is identical.
It should be noted that not drawing all trigger and XOR gate in the present embodiment, only depict part and touch
Send out device and XOR gate.
The course of work of each building block of over-sampling and edge sense circuit is：
The data received, i.e. serial data, trigger are sampled to input serial data simultaneously using 6 phase clocks, tool
Body, that trigger 1010 receives is the clock signal PH0 of zero phase clock input, and what trigger 1011 received is first
The clock signal PH1 of individual phase clock input, what trigger 1012 received is the clock signal of second phase clock input
PH2, that trigger 1013 receives is the clock signal PH3 of the 3rd phase clock input, and what trigger 1014 received is the 4th
The clock signal PH4 of individual phase clock input, what trigger 1015 received is the clock signal of the 5th phase clock input
PH5。
The sampled result of 6 triggers corresponds respectively to q0~q5, the sampled result of adjacent phase clock XOR two-by-two, really
Fixed number according to hopping edge position, and by all output results give rear stage trigger sampling.
To the data of each XOR gate output, sampled, obtain com01-com50, that is, obtain different pieces of information hopping edge
The hopping edge information of position.Wherein, the signal that XOR gate 1020 exports is sampled using PH5 clock signals, XOR gate 1021
The signal of output is sampled using PH0 clock signals, by that analogy, when the signal of the output of XOR gate 1025 uses PH4
Clock signal is sampled.
Wherein, when trigger 1026 export data be high level when, illustrate data jump along position 0-1 phases it
Between, when trigger 1027 export data be high level when, illustrate data jump along position between 1-2 phases, by that analogy,
When the data exported when trigger 10211 are high level, illustrate data jump along position between 5-0 phases.
It should be noted that the present embodiment is explained by taking 6 phase clocks as an example, further, it is also possible to use it
His phase clock.
In the present embodiment, the concrete structure schematic diagram of over-sampling and edge sense circuit is given, according in the present embodiment
Over-sampling and edge sense circuit, it becomes possible to it is determined that each data jump is along position.
Optionally, on the basis of any of the above-described embodiment, edge counts and ballot selection circuit is used for according to per number
According to the data jump of hopping edge position along number, a corresponding data jump is selected along position from all data jumps
When reaching the data jump of default value at first along number along position, it is specifically used for：
The data jump of real-time statistics different pieces of information hopping edge position is along number；
A corresponding data jump is selected along position from all data jumps and reaches present count at first along number
The data jump of value is along position.
Wherein, position of the data jump along position between phase clock adjacent two-by-two.
Specifically, edge counts and the circuit structure reference picture 3 of ballot selection circuit.
Edge counts and ballot selection circuit includes multiple countings and votes circuit and (count and vote circuit
1030- counts and voted circuit 1035) and multiple and door (with door 1040- and door 1045).PH0-PH5 is different phase
The clock signal of clock input, wherein, the present embodiment is still by taking 6 phase clocks as an example.Com01-com50 is that over-sampling and edge are examined
The output signal of slowdown monitoring circuit, glb_rstn represent chip global reset signal, and after electricity on chip, glb_rstn is first set to 0, rearmounted
1.Fc_rstn1 and fc_rstn2 is counter O reset and trigger reset signal, rstn1<0>、rstn2<0>、rstn1<1>、
rstn2<1>……rstn1<5>、rstn2<5>For reset signal, select<0>To select<5>For the data finally determined
Hopping edge position, select<0>Represent the position between PH0 and PH1, select<1>The position between PH1 and PH2 is represented, with
This analogizes, select<5>The position between PH5 and PH0 is represented, when any one in com01-com50 is high level, accordingly
Counting circuit will add 1, when the data jump for having a counting circuit reaches default value along number, produce protection
Protect signals, protect this counting and vote the select signals of circuit output and be not reset, at the same produce rstn1 and
Rstn2 reset signals, process it is excessively multiple with door 1041 to door 1045, obtain fc_rstn1 and fc_rstn2 signals, reset institute
Some countings and the trigger for voting the counter and correlation in circuit.The select signals not being reset will be defeated
Go out to clock selection circuit.Afterwards, count and vote the counter in circuit to restart to count, until some counter
Reach default value.
Specifically, edge counts and voted the cut-away view reference picture 4 of circuit.
Com signals are the output of over-sampling and edge sense circuit, the side information of a certain position are represented, such as com01 tables
Show the information on data jump edge on the position between PH0 and PH1, if a hopping edge, then com01 exports a clock week
The high level of phase, if not exporting low level if, com can be com01/com12/com23/com34/com45/com50；
PH represents a phase clock in N phase clocks, can be PH0~PH5, and PH_b is PH reverse signal；Glb_rstn is
Chip global reset signal, low level are effective；Fc_rstn1/fc_rstn2 is counter O reset and trigger reset signal, its
Middle fc_rstn1 is used for resetting counter Counter, fc_rstn2 and glb_rstn signal with glb_rstn signal logics with rear
It is used for resetting d type flip flop DFF1 after logical AND；GND represents low level, and high level signal HIGH is produced after phase inverter；Count
Device sampling com side information and counting, and give result to comparator Comparator, when the count value of counter is with presetting
When numerical value is the same, comparator output high level, low level is otherwise exported.The high level and and mux of DFF1 sampling comparator outputs
(two, which enter one, goes out selector) latches DFF1 output together.DFF1 output reversely produces rstn1 signals, and rstn1 is mainly used to
Fc_rstn1 signals are produced, reset all counters.DFF2 samples rstn1 signals, d type flip flop DFF2 input and output logic
Or rear generation rstn2 signals, rstn2 are mainly used to produce fc_rstn2 signals, reset all d type flip flop DFF.DFF3 is sampled
Signal after rstn1 is reverse, DFF3 input and output logic or rear generation protect signals, for protecting the meter of counter
When numerical value reaches preset value, select signals are not reset caused by DFF4.DFF4 samples DFF3 output signal outgoing position
Selection signal select.
In the present embodiment, it can be selected when determining data jump along position every time from all data jumps along position
Select out a corresponding data jump and reach the data jump of default value at first along number along position, and then can ensure to select
The phase clock gone out is optimal in all phase clocks, ensures that the serial data of input can be sampled correctly.Meanwhile if
This circuit put can also ensure that will not produce burr when phase clock switches.
Optionally, on the basis of any of the above-described embodiment, clock selection circuit is used for the data jump edge according to reception
Position, an optimal phase clock is selected from N number of phase clock so that data sampling and string turn and circuit according to
When the phase clock selected samples the serial data, it is specifically used for：
According to default data jump along position and the corresponding relation of phase clock, it is determined that with the data jump of reception along position
Corresponding phase clock is put, so that data sampling and string turn and circuit samples the serial number according to the phase clock selected
According to.
Specifically, the data jump from reception is selected from N number of phase clock along position according to the data jump received
It is optimal data recovery clock to become along the farthest phase clock in position, gives this phase clock to data sampling and string turns simultaneously
Circuit is used for data sampling and serioparallel exchange.
Specifically, the circuit structure reference picture 5 of clock selection circuit.
Clock selection circuit has multiple NAND gates, nor gate and phase inverter, in the input of clock selection circuit, PH0-PH5
The clock signal exported for different phase clocks, select<0>-select<5>To count and voting circuit output
Signal, PH0-PH5, select<0>-select<5>It is final defeated after signal is input to multiple NAND gates, nor gate and phase inverter
Go out recov_clock, wherein, recov_clock and and select<0>-select<5>High level signal in signal is input to
And select the phase clock of same NAND gate is identical, i.e.,<0>-select<5>In high level signal be input to it is same
The phase clock of NAND gate is output.
In Fig. 5, GND represents earth terminal, and the function of this clock selection circuit is according to select<0>-select<5>Letter
Number, a phase clock is selected as recovered clock.
It should be noted that from figure 5 it can be seen that work as select<1>For high level when, the phase clock of final choice
For PH3, from circuit theory for, select to jump edge placement (select from data<1>What is represented is the position between PH0 and PH1
Put) farthest phase clock is as optimal recovered clock.
When the optimal phase clock currently selected with last time selection phase clock it is identical, then be continuing with the last time
The phase clock of selection, if the optimal phase clock currently selected and the phase clock of last time selection differ, more
The phase clock used is changed, and then data sampling and string turn and circuit goes sampled data using new phase clock.
Wherein, data sampling and string turn the circuit structure reference picture 6 of simultaneously circuit.
In Fig. 6, data sampling and string turn simultaneously circuit and include multiple DFF (d type flip flop), buffer (buffer), this implementation
In example, using 4 frequency dividings, i.e. div4.Para_clk is parallel output clock signal.
Data sampling and string turn and the input signal of circuit is recov_clock, seri_ of clock selection circuit output
Data and glb_rstn signals, wherein, seri_data is the serial data received, and glb_rstn is chip global reset signal,
When seri_data reaches data sampling and string turns simultaneously circuit, serial mode enters first row DFF, parallel by secondary series DFF
Output.It should be noted that using 4 frequency dividings in the present embodiment, can also be using the frequency dividing of other forms.
In the present embodiment, according to default data jump along position and the corresponding relation of phase clock, it is determined that with reception
Phase clock of the data jump along position correspondence, it is to guarantee to use optimal phase clock sampling serial data.
Optionally, a kind of clock recovery method is provided in another embodiment of the present invention, reference picture 7, including：
S11, over-sampling and edge sense circuit are selecting an optimal phase from all phase clocks every time
During clock, using N number of phase clock while sampling serial data, data are determined according to the sampled result of two neighboring phase clock
Hopping edge position；Wherein, N is positive integer and N is not less than 2；
S12, edge count and ballot selection circuit according to data jump of each data jump along position along number, from institute
Some data jumps select the data jump that a corresponding data jump reaches default value along number at first along position
Along position, and by the data jump of selection clock selection circuit is sent to along position；
S13, clock selection circuit, along position, one are selected from N number of phase clock according to the data jump of reception
Individual optimal phase clock, so that data sampling and string turn and circuit samples the serial number according to the phase clock selected
According to.
Further, over-sampling and edge sense circuit are selecting an optimal phase from all phase clocks every time
During bit clock, using N number of phase clock while sampling serial data, number is determined according to the sampled result of two neighboring phase clock
Before the position of hopping edge, in addition to：
The Data Matching Circuit Matching is input to the serial data of the over-sampling and edge sense circuit with being input to
The data sampling and string turn and circuit serial data due to transmission path different band come delay, with ensure data sampling and
Data, the relativeness of recovered clock and over-sampling and Edge check electricity in the serial data that string turns and inputted in circuit
Data, phase clock corresponding with the recovered clock in the serial data in the serial data inputted in road it is relative
Relation is consistent.
It is that one is selected from all phase clocks when selecting optimal phase clock every time in the present embodiment
Optimal phase clock, it is not optimal using selecting one among the phase clock non-selected from the last time of the prior art
Phase clock, and then when selecting optimal phase clock every time optimal phase clock can be used accurately fast
The serial data that the sampling of speed receives, reduce the probability of serial data sampling failure.
Optionally, on the basis of the embodiment of any of the above-described clock recovery method, over-sampling and edge sense circuit root
Data jump is determined along position according to the sampled result of two neighboring phase clock, including：
By the sampled result XOR of two neighboring phase clock, the position of data edge is obtained.
In the present embodiment, the concrete structure schematic diagram of over-sampling and edge sense circuit is given, according in the present embodiment
Over-sampling and edge sense circuit, it becomes possible to it is determined that each data jump is along position.
Optionally, on the basis of the embodiment of any of the above-described clock recovery method, along the selection circuit root that counts and vote
According to data jump of each data jump along position along number, selected from all data jumps along position corresponding to one
Data jump reaches the data jump of default value along number along position at first, including：
The data jump of real-time statistics different pieces of information hopping edge position is along number；
A corresponding data jump is selected along position from all data jumps and reaches present count at first along number
The data jump of value is along position.
In the present embodiment, it can be selected when determining data jump along position every time from all data jumps along position
Select out a corresponding data jump and reach the data jump of default value at first along number along position, and then can ensure to select
The phase clock gone out is optimal in all phase clocks, ensures that the serial data of input can be sampled correctly.Meanwhile if
This circuit put can also ensure that will not produce burr when phase clock switches.
Optionally, on the basis of the embodiment of any of the above-described clock recovery method, clock selection circuit is according to reception
Data jump selects an optimal phase clock, so that data sampling and string turn along position from N number of phase clock
And circuit is specifically used for when sampling the serial data according to the phase clock selected：
According to default data jump along position and the corresponding relation of phase clock, it is determined that with the data jump of reception along position
Corresponding phase clock is put, so that data sampling and string turn and circuit samples the serial number according to the phase clock selected
According to.
In the present embodiment, according to default data jump along position and the corresponding relation of phase clock, it is determined that with reception
Phase clock of the data jump along position correspondence, it is to guarantee to use optimal phase clock sampling serial data.
It should be noted that the concrete structure and the course of work of each circuit in above-mentioned each method and step, please join
According to the respective description in above-described embodiment, will not be repeated here.
The foregoing description of the disclosed embodiments, professional and technical personnel in the field are enable to realize or using the present invention.
A variety of modifications to these embodiments will be apparent for those skilled in the art, as defined herein
General Principle can be realized in other embodiments without departing from the spirit or scope of the present invention.Therefore, it is of the invention
The embodiments shown herein is not intended to be limited to, and is to fit to and principles disclosed herein and features of novelty phase one
The most wide scope caused.
Claims (10)
- A kind of 1. clock recovery circuitry, it is characterised in that including：Over-sampling and edge sense circuit, edge count and ballot selection circuit, clock selection circuit；The over-sampling and edge sense circuit, the edge count and voted selection circuit, the clock selection circuit successively Connection；The over-sampling and edge sense circuit, for selecting an optimal phase from all phase clocks every time During clock, using N number of phase clock while sampling serial data, data are determined according to the sampled result of two neighboring phase clock Hopping edge position；Wherein, N is positive integer and N is not less than 2；The edge counts and ballot selection circuit, for according to data jump of each data jump along position along number, from All data jumps select the data jump that a corresponding data jump reaches default value along number at first along position Become and be sent to the clock selection circuit along position along position, and by the data jump of selection；The clock selection circuit, for the data jump according to reception along position, one is selected from N number of phase clock Individual optimal phase clock, so that data sampling and string turn and circuit samples the serial number according to the phase clock selected According to.
- 2. clock recovery circuitry according to claim 1, it is characterised in that the over-sampling and edge sense circuit are used for When determining data jump along position according to the sampled result of two neighboring phase clock, it is specifically used for：By the sampled result XOR of two neighboring phase clock, the position of data edge is obtained.
- 3. clock recovery circuitry according to claim 1, it is characterised in that the edge is counted and ballot selection circuit is used According to data jump of each data jump along position along number, from all data jumps selected along position one it is right When the data jump answered reaches the data jump of default value along number along position at first, it is specifically used for：The data jump of real-time statistics different pieces of information hopping edge position is along number；A corresponding data jump is selected along position from all data jumps and reaches default value at first along number Data jump is along position.
- 4. clock recovery circuitry according to claim 1, it is characterised in that the clock selection circuit is used for according to reception Data jump along position, an optimal phase clock is selected from N number of phase clock, so that data sampling and string Turn and circuit according to select phase clock sampling the serial data when, be specifically used for：According to default data jump along position and the corresponding relation of phase clock, it is determined that with the data jump of reception along position pair The phase clock answered, so that data sampling and string turn and circuit samples the serial data according to the phase clock selected.
- 5. clock recovery circuitry according to claim 1, it is characterised in that also include：Data Matching circuit；The Data Matching circuit turns with the data sampling and string and circuit is connected；The Data Matching circuit, the serial data of the over-sampling and edge sense circuit is input to for matching with being input to The data sampling and string turn and the transmission delay of the serial data of circuit, to ensure to input in data sampling and string turn and circuit The serial data in data, the string that inputs in the relativeness of recovered clock and over-sampling and edge sense circuit Data, the relativeness of phase clock corresponding with the recovered clock in the serial data in row data are consistent.
- A kind of 6. clock recovery method, it is characterised in that including：Over-sampling and edge sense circuit make when selecting an optimal phase clock from all phase clocks every time With N number of phase clock while sampling serial data, determine data jump along position according to the sampled result of two neighboring phase clock Put；Wherein, N is positive integer and N is not less than 2；Edge count and ballot selection circuit according to data jump of each data jump along position along number, from all data A corresponding data jump is selected in the position of hopping edge and reaches the data jump of default value at first along number along position, and The data jump of selection is sent to clock selection circuit along position；Clock selection circuit according to the data jump of reception along position, selected from N number of phase clock one it is optimal Phase clock, so that data sampling and string turn and circuit samples the serial data according to the phase clock selected.
- 7. clock recovery method according to claim 6, it is characterised in that over-sampling and edge sense circuit are according to adjacent The sampled result of two phase clocks determines data jump along position, including：By the sampled result XOR of two neighboring phase clock, the position of data edge is obtained.
- 8. clock recovery method according to claim 6, it is characterised in that edge counts and ballot selection circuit is according to every The data jump of individual data hopping edge position selects a corresponding data along position along number from all data jumps Hopping edge number reaches the data jump of default value along position at first, including：The data jump of real-time statistics different pieces of information hopping edge position is along number；A corresponding data jump is selected along position from all data jumps and reaches default value at first along number Data jump is along position.
- 9. clock recovery method according to claim 6, it is characterised in that clock selection circuit is jumped according to the data of reception Become along position, an optimal phase clock is selected from N number of phase clock, so that data sampling and string turn simultaneously circuit When sampling the serial data according to the phase clock selected, it is specifically used for：According to default data jump along position and the corresponding relation of phase clock, it is determined that with the data jump of reception along position pair The phase clock answered, so that data sampling and string turn and circuit samples the serial data according to the phase clock selected.
- 10. clock recovery method according to claim 6, it is characterised in that over-sampling and edge sense circuit are each When an optimal phase clock is selected from all phase clocks, using N number of phase clock simultaneously sampling serial data, Data jump is determined along before position according to the sampled result of two neighboring phase clock, in addition to：The Data Matching Circuit Matching is input to the serial data of the over-sampling and edge sense circuit and is input to described Data sampling and string turn and the transmission delay of the serial data of circuit, to ensure the institute inputted in data sampling and string turn and circuit State the data in serial data, the relativeness of recovered clock and the serial number inputted in over-sampling and edge sense circuit Data, the relativeness of phase clock corresponding with the recovered clock in the serial data in are consistent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710867796.4A CN107508662A (en) | 2017-09-22 | 2017-09-22 | A kind of clock recovery circuitry and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710867796.4A CN107508662A (en) | 2017-09-22 | 2017-09-22 | A kind of clock recovery circuitry and method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107508662A true CN107508662A (en) | 2017-12-22 |
Family
ID=60697480
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710867796.4A Pending CN107508662A (en) | 2017-09-22 | 2017-09-22 | A kind of clock recovery circuitry and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107508662A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108616270A (en) * | 2018-05-16 | 2018-10-02 | 珠海市杰理科技股份有限公司 | Restoring circuit and receiving device |
| CN113886315B (en) * | 2021-09-23 | 2024-05-03 | 珠海一微半导体股份有限公司 | Clock data recovery system, chip and clock data recovery method |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005122460A1 (en) * | 2004-06-04 | 2005-12-22 | Opelcomm, Inc. | Clock recovery system and phase sampling determination system |
| CN101232360A (en) * | 2007-01-23 | 2008-07-30 | 华为技术有限公司 | Data receiving apparatus and method |
| CN102404101A (en) * | 2010-09-15 | 2012-04-04 | 索尼公司 | Phase adjustment circuit, receiving apparatus and communication system |
| CN102457261A (en) * | 2010-10-15 | 2012-05-16 | 台湾积体电路制造股份有限公司 | Glitch-free oversampling clock and data recovery |
| CN102946306A (en) * | 2012-11-23 | 2013-02-27 | 中国电子科技集团公司第三十二研究所 | Clock data recovery circuit structure and digitization clock data recovery method |
| CN103036670A (en) * | 2011-12-27 | 2013-04-10 | 龙迅半导体科技(合肥)有限公司 | Clock recovery circuit and parallel output circuit |
| KR20140141920A (en) * | 2013-06-03 | 2014-12-11 | 고려대학교 산학협력단 | Mutli channel interface apparatus |
| CN104579570A (en) * | 2015-01-14 | 2015-04-29 | 灿芯半导体(上海)有限公司 | Data receiver, data receiving system and data transmission system |
| CN205545202U (en) * | 2016-04-29 | 2016-08-31 | 福建先创通信有限公司 | Digital clustering communication equipment clock data restore circuit |
| CN106844253A (en) * | 2016-12-15 | 2017-06-13 | 北京时代民芯科技有限公司 | A kind of serial communication clock data recovery system of low sampling rate |
| CN207218713U (en) * | 2017-09-22 | 2018-04-10 | 深圳朗田亩半导体科技有限公司 | A kind of clock recovery circuitry |
-
2017
- 2017-09-22 CN CN201710867796.4A patent/CN107508662A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005122460A1 (en) * | 2004-06-04 | 2005-12-22 | Opelcomm, Inc. | Clock recovery system and phase sampling determination system |
| CN101232360A (en) * | 2007-01-23 | 2008-07-30 | 华为技术有限公司 | Data receiving apparatus and method |
| CN102404101A (en) * | 2010-09-15 | 2012-04-04 | 索尼公司 | Phase adjustment circuit, receiving apparatus and communication system |
| CN102457261A (en) * | 2010-10-15 | 2012-05-16 | 台湾积体电路制造股份有限公司 | Glitch-free oversampling clock and data recovery |
| CN103036670A (en) * | 2011-12-27 | 2013-04-10 | 龙迅半导体科技(合肥)有限公司 | Clock recovery circuit and parallel output circuit |
| CN102946306A (en) * | 2012-11-23 | 2013-02-27 | 中国电子科技集团公司第三十二研究所 | Clock data recovery circuit structure and digitization clock data recovery method |
| KR20140141920A (en) * | 2013-06-03 | 2014-12-11 | 고려대학교 산학협력단 | Mutli channel interface apparatus |
| CN104579570A (en) * | 2015-01-14 | 2015-04-29 | 灿芯半导体(上海)有限公司 | Data receiver, data receiving system and data transmission system |
| CN205545202U (en) * | 2016-04-29 | 2016-08-31 | 福建先创通信有限公司 | Digital clustering communication equipment clock data restore circuit |
| CN106844253A (en) * | 2016-12-15 | 2017-06-13 | 北京时代民芯科技有限公司 | A kind of serial communication clock data recovery system of low sampling rate |
| CN207218713U (en) * | 2017-09-22 | 2018-04-10 | 深圳朗田亩半导体科技有限公司 | A kind of clock recovery circuitry |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108616270A (en) * | 2018-05-16 | 2018-10-02 | 珠海市杰理科技股份有限公司 | Restoring circuit and receiving device |
| CN108616270B (en) * | 2018-05-16 | 2021-10-15 | 珠海市杰理科技股份有限公司 | Recovery circuit and receiving apparatus |
| CN113886315B (en) * | 2021-09-23 | 2024-05-03 | 珠海一微半导体股份有限公司 | Clock data recovery system, chip and clock data recovery method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103036670B (en) | A kind of clock recovery circuitry and parallel output circuit | |
| Nanda et al. | Universal asynchronous receiver and transmitter (uart) | |
| US6937683B1 (en) | Compact digital timing recovery circuits, devices, systems and processes | |
| CN104333365B (en) | A kind of three-stage time-to-digital conversion circuit | |
| CN107643674A (en) | A kind of Vernier type TDC circuits based on FPGA carry chains | |
| US8837658B2 (en) | Method and apparatus for sampling a serial data stream using a clock signal, based on a counter pattern | |
| CN2922277Y (en) | Clock burr testing circuit | |
| CN104579455B (en) | A kind of multiple data channel of satellite-borne data transmission transmitter independently selects processing unit | |
| US20150023458A1 (en) | Clock and data recovery using dual manchester encoded data streams | |
| CN205545202U (en) | Digital clustering communication equipment clock data restore circuit | |
| CN207218713U (en) | A kind of clock recovery circuitry | |
| CN109947226A (en) | A kind of UART wake-up circuit of MCU chip | |
| US7084679B2 (en) | Method and apparatus for ensuring synchronization of clocks in a multiple clock system | |
| CN107508662A (en) | A kind of clock recovery circuitry and method | |
| CN103364819B (en) | A kind of high precision coincide counter implementation method based on FPGA | |
| US20040096016A1 (en) | Fast locking clock and data recovery unit | |
| CN109543811A (en) | A kind of counting circuit, method of counting and chip | |
| CN106603442B (en) | A kind of cross clock domain high-speed data communication interface circuit of network-on-chip | |
| CN103684423A (en) | Variable synchronous clock frequency division circuit | |
| CN105141302A (en) | Clock edge based single event upset self-inspection error correction circuit | |
| CN103324597A (en) | Scheme for balancing skew between lanes of high-speed serial digital interface | |
| US7643594B2 (en) | Method for extracting clock in clock data recovery system | |
| CN108964748A (en) | A kind of clock recovery method under maximum Doppler frequency shift | |
| CN109086631A (en) | A kind of strong/weakly mixing type PUF circuit of anti-model attack | |
| CN103580687B (en) | A kind of very high speed digital configurable frequency divider |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |