CN102915750B - Optical disc apparatus and the method judging spindle motor state thereof - Google Patents
Optical disc apparatus and the method judging spindle motor state thereof Download PDFInfo
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- CN102915750B CN102915750B CN201110224793.1A CN201110224793A CN102915750B CN 102915750 B CN102915750 B CN 102915750B CN 201110224793 A CN201110224793 A CN 201110224793A CN 102915750 B CN102915750 B CN 102915750B
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Abstract
A kind of optical disc apparatus and the method judging spindle motor state thereof, the method for described judgement spindle motor state includes: impose driving voltage to spindle motor, and described driving voltage is to control the voltage that spindle motor stops；Read the RF signal on CD；When the frequency of described RF signal is less than or equal to predetermined threshold value, whether it is more than Preset Time according to the time imposing driving voltage to spindle motor and identifies the size of CD；Determine the stand-by period of the size of the CD that correspondence identifies；After continuing the described stand-by period, determine that described spindle motor state is halted state, stop applying described driving voltage.Described optical disc apparatus and judge that the method for spindle motor state simplifies the structure of optical disc apparatus in the case of saving rotation speed monitoring device and measure loop, reduces cost, and can judge whether spindle motor is in halted state easily.
Description
Technical field
The present invention relates to disc drives field, particularly to a kind of optical disc apparatus and judge main shaft horse
The method reaching state.
Background technology
CD storage technique is the new and high technology starting the beginning of the seventies to grow up.Optical disc storage has
Storage density is high, capacity big, can arbitrary access, preserve life-span length, portable stable and reliable in work, light
Band etc. a series of other record the unrivaled advantage of media, be particularly suitable for big data quantity information storage and
Exchange.CD storage technique can not only meet the needs of informationized society ultrahigh-density data storage, and can
Store the information of the medias such as sound, word, figure, image, so that traditional information is deposited simultaneously
Store up, transmit, manage and occupation mode there occurs the change of essence.
On CD, the data of storage are read by optical disc apparatus (commonly referred to CD-ROM drive).Fig. 1 is
The structural representation of optical disc apparatus in prior art.As it is shown in figure 1, described optical disc apparatus includes:
Detection records the light picker (PU, PickUp) 11 of signal on the optical disc 10, and light picker 11 is specially
Laser beam modulation head assembly, typically can be referred to as shaven head；By the RF (Radio of selective combine detection
Frequency) signal produces binary signal and the RF chip 12 of servo error signal；From binary signal
Recover the digital signal processor (DSP) 13 of original data-signal；The main shaft horse of CD 10 rotate at high speed
Reach 14；By the stepper motor 15 moving radially light picker 11 of CD 10；Drive shaft motor 14 and step
Enter the driving chip 16 of motor 15 work；Controller 17 with the whole operation controlling optical disc apparatus.
Spindle motor 14 has FG (Frequency Generator) sensor 141, and it is at spindle motor 14
Produce train of pulse (commonly referred to as FG signal) during rotation, use the operating controlling spindle motor 14.Cause
This, functionally, FG sensor 141 here can be described as again the rotation speed monitoring device of spindle motor 14.Should
Rotation speed monitoring device is a Magnetosensing element, and its characteristic is exactly particularly that the biggest voltage of magnetic field intensity is the biggest,
Vice versa, so for a Magnetosensing element, its voltage is sine wave change, because main shaft
Motor 14 magnetic field intensity of its internal certain point rotating when is in periodically variable.Although this
Magnetosensing element is inside spindle motor 14, but its voltage change signal (FG signal) can be by detection
Loop sends controller 17 to.One rotating speed determining program can be set inside controller 17, in simple terms
It is through the voltage change signal (FG signal) that Magnetosensing element monitors and judges its cycle size (phase
Corresponding rotating speed size), thus judge whether spindle motor stopping action being complete.
But, the spindle motor that have employed FG sensor is relatively costly, and along with spindle motor size becomes
Obtain more and more less, FG sensor is installed and has become more and more difficult.But send out without FG sensor
The FG signal sent, is difficult to again judge whether spindle motor stopping action being complete.If additionally, FG passes
Sensor is damaged, and the rotating speed also resulting in spindle motor cannot be monitored, thus cannot judge main shaft
Whether motor stopping action being complete.
The Chinese patent application of Publication No. CN1423266A discloses one and determines light without FG signal
Dish size and the method and apparatus stopping optical disk rotary.Although the technical scheme of this patent application is capable of
Stop optical disk rotary without FG signal, but this technical scheme is for judging the realization of disc size more
Complexity, thus can not judge whether spindle motor stopping action being complete easily.
Summary of the invention
The problem that the present invention solves is to provide a kind of optical disc apparatus and judges the side of spindle motor state
Method, reduces the cost of optical disc apparatus, can judge whether spindle motor is in stopping easily simultaneously
State.
For solving the problems referred to above, technical scheme provides the judgement master of a kind of optical disc apparatus
The method of axle motor condition, including:
Imposing driving voltage to spindle motor, described driving voltage is to control the voltage that spindle motor stops；
Read the RF signal on CD；
When the frequency of described RF signal is less than or equal to predetermined threshold value, impose driving according to spindle motor
Whether the time of voltage is more than Preset Time is identified the size of CD；
Determine the stand-by period of the size of the CD that correspondence identifies；
After continuing the described stand-by period, determine that described spindle motor state is halted state, stop applying institute
State driving voltage.
Optionally, when the frequency of described RF signal persistently diminishes, determine that described spindle motor state is for subtracting
Speed state.
Optionally, determine that the stand-by period of the size of the CD that correspondence identifies includes: based on described main shaft
The rotating speed of motor determines the corresponding CD identified with the corresponding relation entered between halted state required time
The first stand-by period of size；When light picker is in the border of data of optical disk region and ingress area,
The described stand-by period was the first stand-by period.
Optionally, when the frequency of described RF signal reaches predetermined threshold value, the rotating speed of described spindle motor is
400～500 revs/min.
Optionally, the size of the CD identified is 12cm, and described first stand-by period is 307～384ms.
Optionally, the size of the CD identified is 8cm, and described first stand-by period is 97～121ms.
Optionally, determine that the stand-by period of the size of the CD that correspondence identifies also includes: based on the first half
Footpath, the second radius and described first stand-by period determined for the second stand-by period, and described first radius is for determining
When light picker is in the border of data of optical disk region and ingress area during described first stand-by period half
Footpath, when when described second radius is for determining described second stand-by period, light picker is in data of optical disk region
Radius；When light picker is in data of optical disk region, the described stand-by period was the second stand-by period.
Optionally, before spindle motor imposes driving voltage, the method for described judgement spindle motor state
Also include: reading light picker is in current location information during data of optical disk region, is then shut off tracking
System, described second radius is obtained by described current location information.
Optionally, described CD is DVD, current on described CD of described reading light picker
Positional information includes: read light picker sector auxiliary information of current location on described CD.
Optionally, described CD is CD CD, described reading light picker present bit on described CD
Confidence breath includes: reads and is recorded in the absolute time information on described CD.
Optionally, described Preset Time is 340ms, if it is big to impose time of driving voltage to spindle motor
When 340ms, then the size identifying CD is 12cm, and the size otherwise identifying CD is 8cm.
Optionally, described RF signal is to read when searching system is closed.
For solving the problems referred to above, technical scheme additionally provides a kind of optical disc apparatus, including:
Driving voltage applying unit, for imposing driving voltage to spindle motor, described driving voltage is control
The voltage that spindle motor processed stops；
Read unit, for reading the RF signal on CD；
Dimensions recognition unit, is used for when the frequency of described RF signal is less than or equal to predetermined threshold value, according to
Impose time of driving voltage to spindle motor and whether identify the size of CD more than Preset Time；
Time determines unit, for determining the stand-by period of the size of CD that correspondence identifies；
Status determining unit, for after the most described stand-by period, determines that described spindle motor state is
Halted state, and control the described driving voltage applying unit stopping described driving voltage of applying.
Optionally, described reading unit includes the light picker for reading signal on CD and based on institute
State the RF chip of the signal described RF signal of generation that light picker reads from CD.
Optionally, to determine that unit and status determining unit are integrated in described described Dimensions recognition unit, time
The master chip of optical disc apparatus.
Optionally, the described time determines that unit includes that first determines unit, for based on described spindle motor
Rotating speed and the corresponding relation that enters between halted state required time determine the chi of the corresponding CD identified
The first very little stand-by period；When light picker is in the border of data of optical disk region and ingress area, institute
Stating the stand-by period was the first stand-by period.
Optionally, when the frequency of described RF signal reaches predetermined threshold value, the rotating speed of described spindle motor is
400～500 revs/min.
Optionally, the size of the CD that described Dimensions recognition unit identifies is 12cm, and described first waits
Time is 307～384ms.
Optionally, the size of the CD that described Dimensions recognition unit identifies is 8cm, and described first waits
Time is 97～121ms.
Optionally, the described time determines that unit also includes that second determines unit, for based on the first radius,
Second radius and described first stand-by period determined for the second stand-by period, and described first radius is described for determining
Radius when light picker is in the border of data of optical disk region and ingress area during the first stand-by period, institute
State half when light picker when the second radius is to determine described second stand-by period is in data of optical disk region
Footpath；When light picker is in data of optical disk region, the described stand-by period was the second stand-by period.
Optionally, described driving voltage applying unit before spindle motor imposes driving voltage, described reading
Take unit and also read the light picker current location information in described data of optical disk region, be then shut off tracking
System, described second radius is obtained by described current location information.
Optionally, described CD is DVD, and described reading unit reads light picker at described CD
On current location information include: read light picker sector auxiliary information of current location on described CD.
Optionally, described CD is CD CD, and described reading unit reads light picker on described CD
Current location information include: read be recorded in the absolute time information on described CD.
Optionally, described Preset Time is 340ms, if described driving voltage applying unit is to spindle motor
Impose time of driving voltage more than 340ms time, the most described Dimensions recognition unit identifies the size of CD
For 12cm, the size otherwise identifying CD is 8cm.
Optionally, described RF signal is that described reading unit reads when searching system is closed.
Compared with prior art, the technical program has the advantage that
After applying spindle motor to control its driving voltage stopped, the RF read from CD by detection
The frequency of signal judges the state of spindle motor, when detecting that the frequency of RF signal is less than or equal to presetting threshold
During value, whether the time according to imposing driving voltage to spindle motor identifies CD more than Preset Time
Size, and then determine the stand-by period of the size of CD that correspondence identifies, after continuing the described stand-by period,
Just can determine that spindle motor state is halted state, such that it is able to realize in the case of without FG signal,
Just can judge whether spindle motor is in halted state easily, owing to eliminating for producing FG signal
With rotation speed monitoring device (FG sensor) and the measure loop of detection principal axis motor rotation speed, greatly reduce light
The cost of disk drive device.
In the case of identifying disc size, it is determined by out when light picker is in data of optical disk region
With the first stand-by period during the border of ingress area, and determine based on described first stand-by period and work as light
Pick-up is in the second stand-by period during data of optical disk region, is achieved according to light picker at CD
Diverse location determine the corresponding stand-by period, it is possible to judge whether spindle motor is in more accurately and stop
Only state.
Accompanying drawing explanation
Fig. 1 is the structural representation of optical disc apparatus in prior art；
Fig. 2 is the method for the judgement spindle motor state of the optical disc apparatus that embodiment of the present invention provides
Schematic flow sheet；
Fig. 3 is the embodiment schematic diagram that the optical disc apparatus that the present invention provides judges spindle motor state；
Fig. 4 is ideally to judge, by the frequency of detection RF signal, the schematic diagram that spindle motor stops；
Fig. 5 is to judge, by the frequency of detection RF signal, the schematic diagram that spindle motor stops under actual conditions；
Fig. 6 is the structural representation of the optical disc apparatus that embodiment of the present invention provides.
Detailed description of the invention
In prior art, the rotating speed of the FG signal detection spindle motor generally transmitted by FG sensor,
Thus judge whether spindle motor stopping action being complete, but FG sensor is installed and makes spindle motor cost
Higher.The technical program does not arrange FG sensor on spindle motor, but is read from CD by detection
The frequency of the RF signal taken judges the state of spindle motor, when detect the frequency of RF signal less than or etc.
When predetermined threshold value, according to imposing to spindle motor whether the time controlling its driving voltage stopped is more than
Preset Time identifies the size of CD, and then determines the stand-by period of the size of CD that correspondence identifies,
After the most described stand-by period, determine that spindle motor state is halted state, such that it is able to without FG
In the case of signal, judge whether spindle motor is in halted state easily, reduce CD simultaneously
The cost of driving means.
Understandable, below in conjunction with the accompanying drawings for enabling the above-mentioned purpose of the present invention, feature and advantage to become apparent from
The detailed description of the invention of the present invention is described in detail.
Elaborate detail in the following description so that fully understanding the present invention.But the present invention can
Being different from alternate manner described here implement with multiple, those skilled in the art can be without prejudice to this
Similar popularization is done in the case of invention intension.Therefore the present invention is not by following public detailed description of the invention
Limit.
Fig. 2 is the method for the judgement spindle motor state of the optical disc apparatus that embodiment of the present invention provides
Schematic flow sheet.Refering to Fig. 2, the method for described judgement spindle motor state includes:
Step S101, imposes driving voltage to spindle motor, and described driving voltage stops for controlling spindle motor
Voltage only；
Step S102, reads the RF signal on CD；
Step S103, when the frequency of described RF signal is less than or equal to predetermined threshold value, according to main shaft
Motor imposes time of driving voltage and whether identifies the size of CD more than Preset Time；
Step S104, determines the stand-by period of the size of the CD that correspondence identifies；
Step S105, after continuing the described stand-by period, determines that described spindle motor state is halted state,
Stop applying described driving voltage.
With specific embodiment, above-mentioned optical disc apparatus is judged that the method for spindle motor state is made in detail below
Describe in detail bright.
Fig. 3 is the embodiment schematic diagram that the optical disc apparatus that the present invention provides judges spindle motor state.
As it is shown on figure 3, in the present embodiment, described optical disc apparatus includes: read the light of signal on CD 10
Pick-up (PU) 11；The signal read from CD 10 based on described light picker 11 produces RF letter
Number RF chip 12；The spindle motor 24 of CD 10, is not provided with in spindle motor 24 rotate at high speed
FG sensor；By CD 10 move radially light picker 11 DC motor 25 (i.e. d.c. motor,
Although stepper motor has the precedent of application in optical disc apparatus, but uses DC in the present embodiment
Motor)；The driving chip 16 of drive shaft motor 24 and DC motor 25 work；And master chip 20,
For imposing its driving voltage stopped of control by driving chip 16 to spindle motor 24, it is additionally operable to inspection
Survey the frequency of described RF signal, judge spindle motor 24 according to the frequency of the described RF signal recorded
State, when frequency RF signal being detected is less than or equal to predetermined threshold value, according to spindle motor 24
Whether the time imposing driving voltage identify the size of CD more than Preset Time, and then determines corresponding knowledge
The stand-by period of the size of the CD not gone out, after the most described stand-by period, determine at spindle motor 24
In halted state.In specific embodiment, described master chip 20 incorporates the Digital Signal Processing shown in Fig. 1
The controller 17 of the whole operation of device 13 and control optical disc apparatus.
First, by master chip 20 and driving chip 16, perform step S101, impose to spindle motor
Driving voltage, described driving voltage is to control the voltage that spindle motor stops.Specifically, stop when needs
When spindle motor 24 rotates, master chip 20 sends the instruction stopping spindle motor 24 to driving chip 16,
Under the control of driving chip 16, stop operating by imposing a driving voltage drive shaft motor 24.
In the present embodiment, driving chip 16 drive shaft motor 24 stops operating, the described driving voltage of applying
It is the maximum (such as-7.2V, negative sign represents that this voltage is reverse drive voltages) that can export of drive circuit,
Purpose is to allow spindle motor 24 can stop within the shortest time.
By light picker 11 and RF chip 12, perform step S102, read the RF signal on CD.
Those skilled in the art knows, the data storage method of CD, is to come with continuous print spiral path
Depositing data, the size of the regional of its track and density are just as, and so can ensure that number
According to memory allocation more reasonable.When laser head (light picker) reads signal on CD, logical
Cross searching system and the accuracy of focusing system guarantee reading and stability.Searching system makes laser head energy
The most all the time the track to quasi-spiral orbit, if laser beam just overlaps with disc track, then track
Error be 0.If there is deviation, the photodiode of implementing monitoring finds that two-beam power is different, it
The locator on side is recovered to signal, then moves laser diode, so that it may laser head is positioned track
Center.Focusing system enables laser beam accurately to penetrate in disc tracks and obtains the strongest signal.When swashing
The when that light beam returning from CD, needing through four photodiodes, each photodiode is sent out
The signal demand gone out, through superposition, forms focus error signal.Only export when this focus error signal
When being zero, it is just accurate, if focusing on inaccurate, it is clear that cannot successfully read CD to focus on.
It should be noted that RF signal described in the present embodiment be when searching system is closed based on
Light picker 11 from the signal of disc reading and is processed generation by RF chip 12.Shape is play normally
Under state, focusing system and searching system are all to run, and under non-broadcast state, the most no longer read light
Data on dish, are therefore made without tracking, and now CD is still in rotation status, light picker
11 read is but the signal on trapped orbit, i.e. the 22T signal of CD CD or DVD
18T signal.What the 22T signal of described CD CD or the 18T signal of DVD referred to is exactly the same period
Signal.So-called same period, signal was exactly that CD have to be carved in the beginning of every frame (frame) when being carved into data
Enter, and what the physical length of each frame was just as, therefore it is known that between two same period signals
Time interval is it is known that rotating speed.The signal of CD CD have 3T, 4T, 5T, 6T, 7T, 8T,
These several length of 9T, 10T, 11T, and 22T is exactly two continuous print 11T signals.DVD
Signal has these several length of 3T, 4T, 5T, 6T, 7T, 8T, 9T, 10T, 11T, 14T, and 18T
It it is exactly 14T+4T signal.Wherein, T is regular length, for CD CD, and 1T=0.3 μm, for
DVD, 1T=0.133 μm.These one being quantitatively provided to the data on demodulation CD and determining
Specification.
After disc reading to RF signal, master chip 20 is judged by the frequency detecting described RF signal
The state of spindle motor 24, the state of described spindle motor 24 includes the rotation speed change of spindle motor 24.
From the above mentioned, the frequency of RF signal and rotating speed link together.When rotating speed is the biggest, RF signal
Frequency is the biggest, and rotating speed is the least, and the frequency of RF signal is the least, when the frequency of RF signal is little to certain journey
Degree, then show that spindle motor 24 stops action and has been completed, it is possible to by considering RF signal
Frequency is to judge the state of spindle motor 24, such as: spindle motor 24 rotating speed constantly becomes big, now
State is acceleration mode, and spindle motor 24 rotating speed constantly diminishes, and state now is deceleration regime, and works as
Spindle motor 24 rotating speed becomes 0, and state now is halted state.So, when RF signal being detected
Frequency when persistently diminishing, the state of the most described spindle motor 24 can determine whether, for being in deceleration regime, to work as inspection
The frequency measuring RF signal is little to a certain extent, and the state of the most described spindle motor 24 can determine whether as being in
Halted state.
Fig. 4 is ideally to judge, by the frequency of detection RF signal, the schematic diagram that spindle motor stops.
In conjunction with Fig. 3 and Fig. 4, master chip 20 sends before spindle motor 24 halt instruction to driving chip 16, main
The driving voltage of axle motor 24 is cyclically-varying (sinusoidal waveform), and RF signal is also in the corresponding cycle
Property change, now the frequency of RF signal remains unchanged.In this moment of T1, master chip 20 is to driving
Dynamic chip 16 sends spindle motor 24 halt instruction, under the control of driving chip 16, by imposing one
Driving voltage (making spindle motor 24 invert to order about its voltage stopped) drive shaft motor 24 stops,
As shown in Figure 4, now it can be seen that the frequency of RF signal persistently diminishes (cycle constantly becomes big), until
In this moment of T2, after detecting that the frequency of RF signal reaches certain value, show that spindle motor 24 stops dynamic
It is complete, is i.e. judged as that spindle motor stops.Therefore, T1 to T2 during this period of time, spindle motor
24 are in deceleration regime, the time after T2, and spindle motor 24 is in halted state.
Certainly, above-mentioned is to judge that spindle motor stops by the frequency of detection RF signal in the ideal case,
And in practical situations both, can be because situation that system is saturated occurring so that be difficult to judge in subsequent step
Spindle motor has stopped, and described system is saturated is to cause owing to the function of master chip limits, letter
It it is exactly the master chip RF signal that can not detect that frequency is the least for list.Therefore, as long as detection frequency is the least
RF signal is likely to the situation that system is saturated occur.
Fig. 5 is to judge, by the frequency of detection RF signal, the schematic diagram that spindle motor stops under actual conditions.
As it is shown in figure 5, still in this moment of T1, master chip 20 sends spindle motor 24 to driving chip 16
Halt instruction, under the control of driving chip 16, by imposing a driving voltage drive shaft motor 24
Stop operating.During spindle motor 24 rotating speed reduces, known by the frequency of detection RF signal
The state of spindle motor 24, whole during the frequency of RF signal also constantly diminishing.But due to master
The function of chip 20 limits, after the frequency of RF signal is reduced to a certain degree, and master chip 20 just detection
Less than the frequency of RF signal, i.e. occur in that the situation that system is saturated.Refering to Fig. 5, it is assumed that T3 this
In the individual moment, the situation that the system that occurs in that is saturated, in order to realize can determine spindle motor in subsequent step
24 stop, and embodiment of the present invention, by presetting the threshold value of the frequency of a RF signal, works as detection
Frequency to RF signal is less than or equal to described threshold value set in advance (showing to reach system saturated), and
I.e. it is judged as that spindle motor 24 is in halted state after continuing the stand-by period set in advance.
Certainly, owing to along with the difference of disc size, the described stand-by period set in advance is also different,
Therefore, before determining the described stand-by period, in addition it is also necessary to first determine the size of CD.Inventor is led to
Cross research to find, apply driving voltage to spindle motor, to the system that the reaches saturated required time because of
The size of CD is different, and length during this period of time is the most different, therefore can drive according to imposing to spindle motor
Whether the time of dynamic voltage is more than Preset Time is identified the size of CD.I.e. perform step S103, work as institute
When stating the frequency of RF signal less than or equal to predetermined threshold value, according to spindle motor impose driving voltage time
Between whether identify the size of CD more than Preset Time.
In a particular embodiment, the described default threshold that substantial amounts of actual testing setup is relatively reasonable can be passed through
Value.Here the value of the frequency of RF signal being expressed as RF, then RF=A/B, wherein B is master chip 20
The numerical value of 16 systems drawn after processing the RF signal received, what it represented is the time
Signal (its inverse then represent be frequency signal), this time signal reflection master chip 20 is a cycle
The clock pulse signal corresponding to RF signal number, specifically, with this clock pulse signal detect
During RF signal, can by counter within master chip 20 corresponding to the RF signal in a cycle time
The number of clock signal is calculated, such as the time of master chip 20 clock pulse signal
It is 1 μ s, it is assumed that the clock pulse signal corresponding to RF signal in a cycle has calculated 100,
Time signal the most now is 100 μ s；A is definite value, reflects corresponding pass constant between B with RF
System.After spindle motor 24 halt instruction sends, the rotating speed of spindle motor 24 constantly diminishes, master chip
The value of the B obtained after 20 process can become increasing, and the value of RF the most constantly diminishes, when the value of B
After reaching a higher limit, master chip 20 cannot record the value of B again, then it is believed that now system be saturated.
In a particular embodiment, the higher limit of B may be set to 16 binary value 01F4, the now frequency of RF signal
Value RF=A/01F4 of rate, A/01F4 is described predetermined threshold value.Such as: spindle motor 24 halt instruction
Before sending, the rotating speed of spindle motor is 1500 revs/min, it is assumed that now corresponding RF value is A/0019,
The value of the B that master chip 20 obtains after the processing when rotating speed that 0019 is spindle motor 24 is 1500 revs/min,
After spindle motor 24 halt instruction sends, rotating speed constantly diminishes, and the value of B constantly becomes big, and the value of RF is not
Break and diminish, it is assumed that the value of RF becomes A/0060, A/0100 from A/0019, until after becoming A/01F4,
Then think that system is saturated can not have detected.
As it is shown in figure 5, when the frequency of described RF signal is less than or equal to predetermined threshold value (when system is saturated),
The time imposing driving voltage to spindle motor is T1 to T3 during this period of time.In specific embodiment, institute
Stating Preset Time is 340ms, i.e. when the frequency of described RF signal is less than or equal to predetermined threshold value, if to
Spindle motor impose time of driving voltage more than 340ms time, then the size identifying CD is 12cm,
The size otherwise identifying CD is 8cm.Specifically, can be by arranging a timer, described timer
Beginning timing in imposing driving voltage to spindle motor, to detect the frequency of described RF signal less than or
Terminating timing during equal to predetermined threshold value, result based on timing just can interpolate that out the size of CD.
After identifying the size of CD, perform step S104, determine the size of the CD that correspondence identifies
Stand-by period.Specifically, the described stand-by period, except different because the size of CD is different, also picks up because of light
Take device different, when light picker is in data of optical disk region and leads in CD location difference
When entering border (the alternatively referred to as original position in data of optical disk region) in region, the described stand-by period is
One stand-by period, now, determine that the stand-by period of the size of the CD that correspondence identifies includes: based on institute
The rotating speed stating spindle motor determines corresponding identifying with the corresponding relation entered between halted state required time
First stand-by period of size of CD.
Described first stand-by period can be by setting up rotating speed and the entrance halted state institute of described spindle motor
Between taking time, the model of corresponding relation is set.Obtain being made especially by substantial amounts of actual measurement
The rotating speed of spindle motor and time response, i.e. spindle motor many to the needs that stop operating from certain rotating speed
The repetitive measurement result of few time, the rotating speed setting up spindle motor by the way of matching stops shape with entering
The model of corresponding relation between state required time, corresponding relation here may be linear relationship, it is also possible to
For non-linear relation.
In the present embodiment, obtained by reality measurement is the model of linear relationship.And when the frequency of RF signal
When rate is less than or equal to predetermined threshold value A/01F4, (when reaching described predetermined threshold value A/01F4, i.e. system is satisfied
With), the rotating speed for now CD can obtain result by reality measurement, and no matter disc size is 8cm
Or 12cm, when light picker is in the border of data of optical disk region and ingress area, the main shaft recorded
The rotating speed of motor 24 is about 400～500 revs/min, thus can be according to disc size and now main shaft horse
The rotating speed reaching 24 judges how long should wait, i.e. with time response (stopping operating the required time)
Set for the first stand-by period.When disc size is 12cm, the slope of linear relationship model is about
-1.3rpm/ms (rpm: rev/min, ms: millisecond).The rotating speed of described spindle motor is 400～500rpm,
So allowing principal axis motor rotation speed is exactly (0-400) from the first stand-by period required for 400rpm reaches 0rpm
/ (-1.3) ≈ 307ms, allows principal axis motor rotation speed when first required for 500rpm reaches 0rpm waits
Between be exactly (0-500)/(-1.3) ≈ 384ms, the most described first the stand-by period set scope should be
307～384ms.And because the mass ratio of 8cm dish is relatively light, be easier to stop, say, that its slope
Can be bigger for 12cm dish, the slope obtaining linear relationship model after tested is-4.12
Rpm/ms, thus, when the frequency of RF signal is equal to predetermined threshold value A/01F4 (system is saturated), described
The rotating speed of spindle motor is 400～500rpm, then allow principal axis motor rotation speed reach 0rpm institute from 400rpm
The first stand-by period needed is exactly (0-400)/(-4.12) ≈ 97ms, allows principal axis motor rotation speed from 500rpm
The first stand-by period required for reaching 0rpm is exactly (0-500)/(-4.12) ≈ 121ms, now described
The scope that first stand-by period set should be 97～121ms.In specific embodiment, equally can be by above-mentioned
Timer realizes the timing to described first stand-by period, when the frequency of RF signal reaches predetermined threshold value just
Start this timer and carry out timing, after timing reaches described first stand-by period, terminate timing, now may be used
To be terminated, so that it is determined that spindle motor state is halted state by generation one triggering signal prompt timing.
Additionally, when light picker is in data of optical disk region (the most not including its original position), institute
Stating the stand-by period was the second stand-by period, now determined the stand-by period of the size of the CD that correspondence identifies
Also include: determined for the second stand-by period based on the first radius, the second radius and described first stand-by period,
When described first radius is for determining described first stand-by period, light picker is in data of optical disk region and importing
Radius (distance in the CD center of circle to track residing for light picker) during the border in region, described second radius
Radius when light picker is in data of optical disk region during for determining described second stand-by period.
When light picker is in data of optical disk region, before imposing driving voltage to spindle motor, also
Including: reading light picker is in current location information during data of optical disk region, and being then shut off tracking is
System, described second radius is obtained by described current location information.Described current location information for
Different optical disc types is different, when described CD is DVD, then reads light picker at light
Current location information on dish refers to read light picker sector auxiliary information of current location on CD
(ID)；If described CD is CD CD, then reads light picker current location information on CD and refer to
Be to read the absolute time information (Sub-Q) that is recorded on described CD.It should be noted that to master
Before axle motor imposes driving voltage, this driving voltage can be preset, drive completing to preset
After voltage, before searching system is closed (now cannot read ID/Sub-Q), need to read
Take ID/Sub-Q, in order to ensure that the ID/Sub-Q read is the ID/Sub-Q of searching system turn-off transient really,
Can only immediately close off searching system after running through ID/Sub-Q, hereafter spindle motor is in the applying of driving voltage
Under reduce speed now.
Usually, regardless of the size of CD, the value of described first radius is known, i.e. for CD
CD, the first radius is 25mm, and for DVD, the first radius is 24mm.Additionally, light
Pick-up is in described second on any position (not including its original position) in data of optical disk region etc.
Treating that the time is directly proportional to the rotating speed (angular velocity omega) of CD, again because ω=v/r, wherein v is linear velocity,
R is described second radius, and therefore, the second stand-by period was directly proportional to v/r.In fact the linear velocity of CD
It is constant, caused for the second stand-by period be directly proportional to 1/r.As a result, light picker is in data of optical disk district
Described second stand-by period on the optional position in territory and light picker are in data of optical disk region and Lead-In Area
The relation of described first stand-by period during border in territory is:
Second stand-by period=(the first radius × the first stand-by period)/the second radius (1)
Wherein, the second radius can be expressed as:
Second radius=the first radius+track pitch × physical track number (2)
For CD, track pitch is known constant, for the second stand-by period, and and if only if thing
If reason track number provides, just can pass through formula (1), (2) are calculated.
And described physical track number can be by what the ID/Sub-Q that light picker read was derived by,
Concrete derivation dawn known to those skilled in the art, do not repeat them here.
Therefore, after obtaining described first stand-by period by measurement, according to the first stand-by period, the first half
Footpath, the second radius just can draw described second stand-by period when light picker is in data of optical disk region.
After determining the stand-by period of size of CD that correspondence identifies, perform step S105, continue institute
After stating the stand-by period, determine that described spindle motor state is halted state, stop applying described driving voltage.
As it is shown in figure 5, this moment spindle motor 24 of T1 initially enters deceleration regime, this moment of T3
Detect that the frequency of RF signal, equal to predetermined threshold value (system is saturated), waits according to the default stand-by period
To this moment of T4, the i.e. stand-by period that T4=T3+ presets, this moment of T4 is judged to spindle motor
24 enter halted states, now stop applying described driving voltage, and i.e. stopping powers to spindle motor 24 (leads
The input voltage of axle motor 24 is 0).Therefore, during this period of time, spindle motor 24 is in and subtracts T1 to T4
Speed state, wherein, T1 to T3 can detect the frequency of RF signal during this period of time, during T3 to T4 this section
Between (stand-by period) frequency of RF signal, the time after T4, spindle motor 24 can not be detected
It is in halted state.
It should be noted that above-mentioned actual measurement refers to set out relatively reasonable described default threshold
Value and the first stand-by period and the research work done, do not imply that judge described in embodiment of the present invention main
Being embodied as of the method that axle motor stops, owing to implementing the light of the method that described judgement spindle motor stops
Disk drive device does not configure the rotation speed monitoring devices such as FG sensor, therefore can not obtain certain moment main shaft
The concrete rotating speed of motor is how many, but reality is measured when, can be by optical disc apparatus
On the rotation speed monitoring devices such as FG sensor are set, thus detect that the concrete rotating speed of certain moment spindle motor is for many
Few.
Additionally, A here also can be by what the result of actual measurement was calculated indirectly.In theory
A should be certain value, can be by looking for a method indirectly to calculate concrete numerical value, such as: first find out and leading
B in the formula RF=A/B that the rotating speed of axle motor is corresponding when being 1500 revs/min (frequency is 25Hz)
For how much, in formula RF=A/B corresponding time 1200 revs/min (frequency is 20Hz), B is how many ...
By that analogy, until it is how many for finding out B in formula RF=A/B corresponding when 200 revs/min, by many
Secondary measurement (gets rid of error) as far as possible, finally draws the concrete numerical value of A.In the present embodiment, surveyed by reality
The result of amount show that the concrete numerical value of A is 15E0 (16 system number) indirectly.It should be noted that here
The concrete numerical value of the A drawn is looking for for convenience a little and calculating and obtain during reality is measured
Individual mean value, the value actually calculated under different rotating speeds is different, such as: 1500 revs/min
Clock show that the value of A corresponds to 16D4, and 450 revs/min of values drawing A correspond to EC7.Although A takes
Can there is certain error in mean value, but mainly consider when actual set threshold value to reach 400～500 at rotating speed
Rev/min time in the case of be set, so this error does not affect for whether reaching system saturated
Judge, the most do not affect the judgement that spindle motor stops.
Method based on above-mentioned judgement spindle motor state, embodiment of the present invention additionally provides a kind of CD
Driving means.Fig. 6 is the structural representation of the optical disc apparatus that embodiment of the present invention provides, such as Fig. 6
Shown in, described optical disc apparatus includes:
Driving voltage applying unit 201, for imposing driving voltage to spindle motor, described driving voltage is
Control the voltage that spindle motor stops；
Read unit 202, for reading the RF signal on CD；
Dimensions recognition unit 203, is used for when the frequency of described RF signal is less than or equal to predetermined threshold value,
Whether it is more than Preset Time according to the time imposing driving voltage to spindle motor and identifies the size of CD；
Described Dimensions recognition unit 203 is connected with described driving voltage applying unit 201, reading unit 202；
Time determines unit 204, for determining the stand-by period of the size of CD that correspondence identifies；Described
Time determines that unit 204 is connected with described Dimensions recognition unit 203；The described time determines that unit 204 can
Unit is determined, for rotating speed based on described spindle motor and entrance halted state required time including first
Between corresponding relation determine first stand-by period of size of CD that correspondence identifies；Work as light picker
When being in the border of data of optical disk region and ingress area, the described stand-by period was the first stand-by period；Institute
The time of stating determines that unit 204 may also include second and determines unit, for based on the first radius, the second radius
Determining for the second stand-by period with described first stand-by period, described first radius is for determining that described first waits
Radius when light picker is in the border of data of optical disk region and ingress area during the time, described the second half
Radius when light picker is in data of optical disk region when footpath is to determine described second stand-by period；When light picks up
Taking device when being in data of optical disk region, the described stand-by period was the second stand-by period；
Status determining unit 205, for after the most described stand-by period, determines described spindle motor state
For halted state, and control described driving voltage applying unit 201 and stop applying described driving voltage；Institute
State status determining unit 205 and determine that with the described time unit 204, driving voltage applying unit 201 are connected.
In specific embodiment, in conjunction with Fig. 3, described driving voltage applying unit 201 is specifically as follows driving core
Sheet 16, described reading unit 202 can include the light picker 11 for reading signal on CD and base
RF chip 12 in the signal described RF signal of generation that described light picker 11 reads from CD.Institute
State Dimensions recognition unit 203, the time determines unit 204 and status determining unit 205 is integrated in described CD
The master chip 20 of driving means.
It is embodied as referring to the judgement main shaft of above-mentioned optical disc apparatus about described optical disc apparatus
The method of motor condition, does not repeats them here.
To sum up, embodiment of the present invention provides optical disc apparatus and judge the side of spindle motor state
Method, at least has the advantages that
After applying spindle motor to control its driving voltage stopped, the RF read from CD by detection
The frequency of signal judges the state of spindle motor, when detecting that the frequency of RF signal is less than or equal to presetting threshold
During value, whether the time according to imposing driving voltage to spindle motor identifies CD more than Preset Time
Size, and then determine the stand-by period of the size of CD that correspondence identifies, after continuing the described stand-by period,
Just can determine that spindle motor state is halted state, such that it is able to realize in the case of without FG signal,
Just can judge whether spindle motor is in halted state easily, owing to eliminating for producing FG signal
With rotation speed monitoring device (FG sensor) and the measure loop of detection principal axis motor rotation speed, greatly reduce light
The cost of disk drive device.
In the case of identifying disc size, it is determined by out when light picker is in data of optical disk region
With the first stand-by period during the border of ingress area, and determine based on described first stand-by period and work as light
Pick-up is in the second stand-by period during data of optical disk region, is achieved according to light picker at CD
Diverse location determine the corresponding stand-by period, it is possible to judge whether spindle motor is in more accurately and stop
Only state.
Although the present invention is open as above with preferred embodiment, but it is not for limiting the present invention, appoints
What those skilled in the art without departing from the spirit and scope of the present invention, may be by the disclosure above
Technical solution of the present invention is made possible variation and amendment by method and technology contents, therefore, every does not takes off
From the content of technical solution of the present invention, it is any that above example is made by the technical spirit of the foundation present invention
Simple modification, equivalent variations and modification, belong to the protection domain of technical solution of the present invention.
Claims (25)
1. the method for the judgement spindle motor state of an optical disc apparatus, it is characterised in that including:
Imposing driving voltage to spindle motor, described driving voltage is to control the voltage that spindle motor stops；
Read the RF signal on CD；
When the frequency of described RF signal is less than or equal to predetermined threshold value, impose driving according to spindle motor
Whether the time of voltage is more than Preset Time is identified the size of CD；
Determine the stand-by period of the size of the CD that correspondence identifies；
After continuing the described stand-by period, determine that described spindle motor state is halted state, stop applying described
Driving voltage.
The method of judgement spindle motor state the most according to claim 1, it is characterised in that when described
When the frequency of RF signal persistently diminishes, determine that described spindle motor state is deceleration regime.
The method of judgement spindle motor state the most according to claim 1, it is characterised in that determine correspondence
The stand-by period of the size of the CD identified includes: rotating speed based on described spindle motor stops with entrance
Only the corresponding relation between state required time determine CD that correspondence identifies size first etc.
Treat the time；When light picker is in the border of data of optical disk region and ingress area, during described wait
Between be the first stand-by period.
The method of judgement spindle motor state the most according to claim 3, it is characterised in that described RF
When the frequency of signal reaches predetermined threshold value, the rotating speed of described spindle motor is 400～500 revs/min.
The method of judgement spindle motor state the most according to claim 4, it is characterised in that identify
The size of CD is 12cm, and described first stand-by period is 307～384ms.
The method of judgement spindle motor state the most according to claim 4, it is characterised in that identify
The size of CD is 8cm, and described first stand-by period is 97～121ms.
The method of judgement spindle motor state the most according to claim 3, it is characterised in that determine correspondence
The stand-by period of the size of the CD identified also includes: based on the first radius, the second radius and described
First stand-by period determined for the second stand-by period, and described first radius is for determining described first stand-by period
Time light picker radius when being in the border of data of optical disk region and ingress area, described second radius
Radius when light picker is in data of optical disk region during for determining described second stand-by period；When light picks up
Taking device when being in data of optical disk region, the described stand-by period was the second stand-by period.
The method of judgement spindle motor state the most according to claim 7, it is characterised in that to main shaft horse
Reach before imposing driving voltage, also include: that reads when light picker is in data of optical disk region is current
Positional information, is then shut off searching system, and described second radius is to be obtained by described current location information
?.
The method of judgement spindle motor state the most according to claim 8, it is characterised in that described CD
For DVD, described reading light picker current location information on described CD includes: read
Take light picker sector auxiliary information of current location on described CD.
The method of judgement spindle motor state the most according to claim 8, it is characterised in that described CD
For CD CD, described reading light picker current location information on described CD includes: read
It is recorded in the absolute time information on described CD.
The method of 11. judgement spindle motor state according to claim 1, it is characterised in that described default
Time is 340ms, if to spindle motor impose time of driving voltage more than 340ms time, then know
The size not going out CD is 12cm, and the size otherwise identifying CD is 8cm.
The method of 12. judgement spindle motor state according to claim 1, it is characterised in that described RF
Signal is to read when searching system is closed.
13. 1 kinds of optical disc apparatus, it is characterised in that including:
Driving voltage applying unit, for imposing driving voltage to spindle motor, described driving voltage is for controlling
The voltage that spindle motor stops；
Read unit, for reading the RF signal on CD；
Dimensions recognition unit, is used for when the frequency of described RF signal is less than or equal to predetermined threshold value, according to
Impose time of driving voltage to spindle motor and whether identify the size of CD more than Preset Time；
Time determines unit, for determining the stand-by period of the size of CD that correspondence identifies；
Status determining unit, for after the most described stand-by period, determines that described spindle motor state is for stopping
Only state, and control the described driving voltage applying unit stopping described driving voltage of applying.
14. optical disc apparatus according to claim 13, it is characterised in that described reading unit includes
For reading the light picker of signal on CD and reading from CD based on described light picker
Signal produces the RF chip of described RF signal.
15. optical disc apparatus according to claim 13, it is characterised in that described Dimensions recognition unit,
Time determines that unit and status determining unit are integrated in the master chip of described optical disc apparatus.
16. optical disc apparatus according to claim 13, it is characterised in that the described time determines unit
Determine unit including first, taken with entering halted state for rotating speed based on described spindle motor
First stand-by period of the size of the CD that the correspondence that determines the corresponding relation between identifies；When light picks up
When taking the border that device is in data of optical disk region and ingress area, when the described stand-by period is the first wait
Between.
17. optical disc apparatus according to claim 16, it is characterised in that the frequency of described RF signal
When rate reaches predetermined threshold value, the rotating speed of described spindle motor is 400～500 revs/min.
18. optical disc apparatus according to claim 17, it is characterised in that described Dimensions recognition unit
The size of the CD identified is 12cm, and described first stand-by period is 307～384ms.
19. optical disc apparatus according to claim 17, it is characterised in that described Dimensions recognition unit
The size of the CD identified is 8cm, and described first stand-by period is 97～121ms.
20. optical disc apparatus according to claim 16, it is characterised in that the described time determines unit
Also include that second determines unit, for based on the first radius, the second radius and described first stand-by period
Determined for the second stand-by period, when described first radius is for determining described first stand-by period at light picker
Radius when the border of data of optical disk region and ingress area, described second radius is for determining described
Radius when light picker is in data of optical disk region during two stand-by period；When light picker is in CD
During data area, the described stand-by period was the second stand-by period.
21. optical disc apparatus according to claim 20, it is characterised in that described driving voltage applies
Before unit imposes driving voltage to spindle motor, described reading unit also reads light picker described
The current location information in data of optical disk region, is then shut off searching system, and described second radius is to pass through
Described current location information obtains.
22. optical disc apparatus according to claim 21, it is characterised in that described CD is DVD
CD, described reading unit reads light picker current location information on described CD and includes: read
Take light picker sector auxiliary information of current location on described CD.
23. optical disc apparatus according to claim 21, it is characterised in that described CD is CD light
Dish, described reading unit reads light picker current location information on described CD and includes: read
It is recorded in the absolute time information on described CD.
24. optical disc apparatus according to claim 13, it is characterised in that described Preset Time is
340ms, if the time that described driving voltage applying unit imposes driving voltage to spindle motor be more than
During 340ms, it is 12cm that the most described Dimensions recognition unit identifies the size of CD, otherwise identifies
The size of CD is 8cm.
25. optical disc apparatus according to claim 13, it is characterised in that described RF signal is institute
State and read what unit read when searching system is closed.
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| CN111751567A (en) * | 2019-03-28 | 2020-10-09 | 比亚迪股份有限公司 | Rotational speed detection device and vehicle |
| CN111464091B (en) * | 2020-04-08 | 2021-12-03 | 成都极米科技股份有限公司 | Control method and control device of shift motor and projection system |
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| CN1423266A (en) * | 2001-12-04 | 2003-06-11 | Lg电子株式会社 | Method and apparatus for determining CD size without FG signal and stopping CD rotation |
| CN1444219A (en) * | 2002-03-13 | 2003-09-24 | Lg电子株式会社 | Method for defining deficiency of optical recording medium and disk size and its equipment |
| US20050073925A1 (en) * | 2003-10-01 | 2005-04-07 | Mediatek Inc. | Method and system for identifying the size of an opitcal disc |
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| JPH067423B2 (en) * | 1984-03-16 | 1994-01-26 | パイオニア株式会社 | Disk size detection circuit |
| CN101114487B (en) * | 2006-07-28 | 2014-06-11 | 扬智科技股份有限公司 | CD detecting method |
| CN101261858A (en) * | 2007-03-08 | 2008-09-10 | 扬智科技股份有限公司 | CD form judgement method and CD device for judging this form |
| US7667451B2 (en) * | 2007-11-30 | 2010-02-23 | Philips & Lite-On Digital Solutions Corporation | Method for determining size of optical disc inserted into optical disc drive |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1423266A (en) * | 2001-12-04 | 2003-06-11 | Lg电子株式会社 | Method and apparatus for determining CD size without FG signal and stopping CD rotation |
| CN1444219A (en) * | 2002-03-13 | 2003-09-24 | Lg电子株式会社 | Method for defining deficiency of optical recording medium and disk size and its equipment |
| US20050073925A1 (en) * | 2003-10-01 | 2005-04-07 | Mediatek Inc. | Method and system for identifying the size of an opitcal disc |
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