CN102915750A - Optical disk driving device and method for judging spindle motor state thereof - Google Patents
Optical disk driving device and method for judging spindle motor state thereof Download PDFInfo
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Abstract
The invention discloses an optical disk driving device and a method for judging a spindle motor state thereof. The method for judging the spindle motor state comprises the steps as follows: applying driving voltage to a spindle motor, wherein the driving voltage controls the spindle motor to stop; reading an RF (radio frequency) signal on an optical disk, when the frequency of the RF signal is smaller than or equal to a preset threshold value, identifying the size of the optical disk according to the fact that whether the time for applying the driving voltage to the spindle motor is longer than preset time or not; determining waiting time corresponding to the identified size of the optical disk; and after lasting the waiting time, determining that the spindle motor state is in a stop state, and stopping applying the driving voltage. The optical disk driving device and the method for judging spindle motor state thereof can save a speed monitor, simplifies the structure of the optical disk driving device during loop detection, reduces the cost, and conveniently judges out whether the spindle motor is in the stop state or not.
Description
Technical field
The present invention relates to the disc drives field, particularly the method for a kind of optical disc apparatus and judgement Spindle Motor state thereof.
Background technology
CD storage technique is a new and high technology that begins to grow up the beginning of the seventies.But optical disc storage has the large random access of storage density height, capacity, preserve the life-span long, working stability is reliable, the light unrivaled advantage of a series of other recording mediums such as portable, is particularly suitable for storage and the exchange of big data quantity information.CD storage technique can not only satisfy the needs of informationized society magnanimity information storage, and the information of the medias such as stored sound, literal, figure, image simultaneously, thereby make traditional information storage, transmission, management and using mode that the variation of essence occur.
The data of storing on the CD read by optical disc apparatus (being commonly referred to CD-ROM drive).Fig. 1 is the structural representation of optical disc apparatus in the prior art.As shown in Figure 1, described optical disc apparatus comprises: the light picker (PU, PickUp) 11 of detection record signal on CD 10, and light picker 11 is specially laser beam modulation head assembly, generally can be referred to as shaven head; Produce the RF chip 12 of binary signal and servo error signal by the RF of combine detection (Radio Frequency) signal optionally; Recover the digital signal processor (DSP) 13 of original data-signal from binary signal; Spindle Motor 14 with High Rotation Speed CD 10; The step motor that moves radially light picker 11 15 by CD 10; The driving chip 16 of drive shaft motor 14 and step motor 15 work; Controller 17 with the whole operation of controlling optical disc apparatus.
Spindle Motor 14 has FG (Frequency Generator) sensor 141, and it produces train of impulses (being commonly referred to as the FG signal) during Spindle Motor 14 rotations, use the running of control Spindle Motor 14.Therefore, on function, the FG sensor 141 here can be described as again the rotation speed monitoring device of Spindle Motor 14.This rotation speed monitoring device is a Magnetosensing element, its characteristic is exactly that the larger voltage of magnetic field intensity is just larger particularly, vice versa, so for a Magnetosensing element, its voltage is sinusoidal wave to be changed, because Spindle Motor 14 its inner certain any magnetic field intensity in rotation is to be periodically variable.Although this Magnetosensing element is in Spindle Motor 14 inside, its voltage change signal (FG signal) can send controller 17 to by detecting the loop.In controller 17 inside a rotating speed determining program can be set, be exactly to judge its cycle size (corresponding rotating speed size) by the voltage change signal (FG signal) that Magnetosensing element monitors in simple terms, thereby judge that Spindle Motor stops action and whether finishes.
But, adopted the Spindle Motor cost of FG sensor higher, and along with the Spindle Motor size becomes more and more less, the FG sensor be installed also become more and more difficult.If but the FG signal that does not have the FG sensor to send is difficult to again judge that Spindle Motor stops action and whether finishes.In addition, if the FG sensor is damaged, also can cause the rotating speed of Spindle Motor can't obtain monitoring, thereby can't judge that Spindle Motor stops action and whether finishes.
Publication number is that the Chinese patent application of CN1423266A discloses and a kind ofly determines disc size and stop the method and apparatus of optical disk rotary without the FG signal.Whether although the technical scheme of this patented claim can realize stopping optical disk rotary without the FG signal, this technical scheme is comparatively complicated for the realization of judging disc size, stop action and finish thereby can not judge easily Spindle Motor.
Summary of the invention
The problem that the present invention solves provides the method for a kind of optical disc apparatus and judgement Spindle Motor state thereof, reduces the cost of optical disc apparatus, can judge easily Spindle Motor simultaneously and whether be in halted state.
For addressing the above problem, technical scheme of the present invention provides a kind of method of judgement Spindle Motor state of optical disc apparatus, comprising:
Impose driving voltage to Spindle Motor, the voltage that described driving voltage stops for the control Spindle Motor;
Read the RF signal on the CD;
When the frequency of described RF signal is less than or equal to predetermined threshold value, whether identify the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor;
The stand-by period of the size of the CD that definite correspondence identifies;
After continuing the described stand-by period, determine that described Spindle Motor state is halted state, stop to apply described driving voltage.
Optionally, when the frequency of described RF signal continues to diminish, determine that described Spindle Motor state is deceleration regime.
Optionally, the stand-by period of determining the size of the CD that correspondence identifies comprises: based on the rotating speed of described Spindle Motor and the first stand-by period that enters corresponding relation between the halted state required time and determine the size of the corresponding CD that identifies; When light picker was in the border of data of optical disk zone and ingress area, the described stand-by period was the first stand-by period.
Optionally, when the frequency of described RF signal reached predetermined threshold value, the rotating speed of described Spindle Motor was 400～500 rev/mins.
Optionally, the CD that identifies is of a size of 12cm, and described the first stand-by period is 307～384ms.
Optionally, the CD that identifies is of a size of 8cm, and described the first stand-by period is 97～121ms.
Optionally, the stand-by period of the size of the CD that definite correspondence identifies also comprises: determined for the second stand-by period based on the first radius, the second radius and described the first stand-by period, radius when described the first radius light picker when determining described the first stand-by period is in the border of data of optical disk zone and ingress area, described the second radius light picker when determining described the second stand-by period is in the radius of data of optical disk when regional; When light picker was in the data of optical disk zone, the described stand-by period was the second stand-by period.
Optionally, before imposing driving voltage to Spindle Motor, the method of described judgement Spindle Motor state also comprises: read light picker and be in the data of optical disk current location information in when zone, then close searching system, described the second radius obtains by described current location information.
Optionally, described CD is the DVD CD, and the described light picker that reads comprises at the current location information on the described CD: the sector auxiliary information that reads light picker current location on described CD.
Optionally, described CD is the CD CD, and the described light picker that reads comprises at the current location information on the described CD: read the absolute time information that is recorded on the described CD.
Optionally, described Preset Time is 340ms, if the time that imposes driving voltage to Spindle Motor during greater than 340ms, is then identified CD and is of a size of 12cm, is of a size of 8cm otherwise identify CD.
Optionally, described RF signal is to read under the state that searching system is closed.
For addressing the above problem, technical scheme of the present invention also provides a kind of optical disc apparatus, comprising:
The driving voltage applying unit is used for imposing driving voltage to Spindle Motor, the voltage that described driving voltage stops for the control Spindle Motor;
Reading unit is used for reading the RF signal on the CD;
The size recognition unit is used for when the frequency of described RF signal is less than or equal to predetermined threshold value, whether identifies the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor;
The time determining unit is for the stand-by period of the size of determining the CD that correspondence identifies;
Status determining unit is used for determining that described Spindle Motor state is halted state after continuing the described stand-by period, and controls described driving voltage applying unit and stop to apply described driving voltage.
Optionally, described reading unit comprises be used to the light picker that reads signal on the CD and the RF chip that produces described RF signal based on the signal that described light picker reads from CD.
Optionally, described size recognition unit, time determining unit and status determining unit are integrated in the master chip of described optical disc apparatus.
Optionally, described time determining unit comprises the first determining unit, is used for based on the rotating speed of described Spindle Motor and the first stand-by period that enters corresponding relation between the halted state required time and determine the size of the corresponding CD that identifies; When light picker was in the border of data of optical disk zone and ingress area, the described stand-by period was the first stand-by period.
Optionally, when the frequency of described RF signal reached predetermined threshold value, the rotating speed of described Spindle Motor was 400～500 rev/mins.
Optionally, the CD that described size recognition unit identifies is of a size of 12cm, and described the first stand-by period is 307～384ms.
Optionally, the CD that described size recognition unit identifies is of a size of 8cm, and described the first stand-by period is 97～121ms.
Optionally, described time determining unit also comprises the second determining unit, be used for determining for the second stand-by period based on the first radius, the second radius and described the first stand-by period, radius when described the first radius light picker when determining described the first stand-by period is in the border of data of optical disk zone and ingress area, described the second radius light picker when determining described the second stand-by period is in the radius of data of optical disk when regional; When light picker was in the data of optical disk zone, the described stand-by period was the second stand-by period.
Optionally, before described driving voltage applying unit imposes driving voltage to Spindle Motor, described reading unit also reads light picker at the current location information in described data of optical disk zone, then closes searching system, and described the second radius obtains by described current location information.
Optionally, described CD is the DVD CD, and described reading unit reads light picker and comprises at the current location information on the described CD: the sector auxiliary information that reads light picker current location on described CD.
Optionally, described CD is the CD CD, and described reading unit reads light picker and comprises at the current location information on the described CD: read the absolute time information that is recorded on the described CD.
Optionally, described Preset Time is 340ms, if described driving voltage applying unit imposes time from driving voltage to Spindle Motor during greater than 340ms, then described size recognition unit identifies CD and is of a size of 12cm, is of a size of 8cm otherwise identify CD.
Optionally, described RF signal is that described reading unit reads under the state that searching system is closed.
Compared with prior art, the technical program has the following advantages:
To Spindle Motor apply control its driving voltage that stops after, judge the state of Spindle Motor by the frequency that detects the RF signal that reads from CD, when the frequency that detects the RF signal is less than or equal to predetermined threshold value, whether identify the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor, and then the stand-by period of the size of the CD that identifies of definite correspondence, after continuing the described stand-by period, just can determine that the Spindle Motor state is halted state, thereby can be implemented in the situation without the FG signal, just can judge easily Spindle Motor and whether be in halted state, owing to saved for generation of rotation speed monitoring device (FG sensor) and the detection loop of FG signal to detect principal axis motor rotation speed, greatly reduced the cost of optical disc apparatus.
Identifying in the situation of disc size, by determining the first stand-by period when light picker is in the border of data of optical disk zone and ingress area, and determine when light picker based on described the first stand-by period and to be in data of optical disk second stand-by period in when zone, realize thus determining the corresponding stand-by period according to light picker at the diverse location of CD, can judge more accurately Spindle Motor and whether be in halted state.
Description of drawings
Fig. 1 is the structural representation of optical disc apparatus in the prior art;
Fig. 2 is the schematic flow sheet of method of the judgement Spindle Motor state of the optical disc apparatus that provides of embodiment of the present invention;
Fig. 3 is the embodiment synoptic diagram that optical disc apparatus provided by the invention is judged the Spindle Motor state;
Fig. 4 ideally judges the synoptic diagram that Spindle Motor stops by the frequency that detects the RF signal;
Fig. 5 judges the synoptic diagram that Spindle Motor stops by the frequency that detects the RF signal under the actual conditions;
Fig. 6 is the structural representation of the optical disc apparatus that provides of embodiment of the present invention.
Embodiment
In the prior art, usually pass through the rotating speed of the FG input Spindle Motor of FG sensor transmission, thereby judge that Spindle Motor stops action and whether finishes, make the Spindle Motor cost higher but the FG sensor is installed.The technical program does not arrange the FG sensor at Spindle Motor, but judge the state of Spindle Motor by the frequency that detects the RF signal that reads from CD, when the frequency that detects the RF signal is less than or equal to predetermined threshold value, whether identify the size of CD greater than Preset Time according to the time that imposes its driving voltage that stops of control to Spindle Motor, and then the stand-by period of the size of the CD that identifies of definite correspondence, after continuing the described stand-by period, determine that the Spindle Motor state is halted state, thereby can be in the situation without the FG signal, judge easily Spindle Motor and whether be in halted state, reduced simultaneously the cost of optical disc apparatus.
For above-mentioned purpose of the present invention, feature and advantage can more be become apparent, below in conjunction with accompanying drawing the specific embodiment of the present invention is described in detail.
Set forth detail in the following description so that fully understand the present invention.But the present invention can be different from alternate manner described here and implements with multiple, and those skilled in the art can do similar popularization in the situation of intension of the present invention.Therefore the present invention is not subjected to the restriction of following public embodiment.
Fig. 2 is the schematic flow sheet of method of the judgement Spindle Motor state of the optical disc apparatus that provides of embodiment of the present invention.Consult Fig. 2, the method for described judgement Spindle Motor state comprises:
Step S101 imposes driving voltage to Spindle Motor, the voltage that described driving voltage stops for the control Spindle Motor;
Step S102 reads the RF signal on the CD;
Whether step S103 when the frequency of described RF signal is less than or equal to predetermined threshold value, identifies the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor;
Step S104 determines stand-by period of the size of the CD that correspondence identifies;
Step S105 after the lasting described stand-by period, determines that described Spindle Motor state is halted state, stops to apply described driving voltage.
The below elaborates with the method for specific embodiment to the judgement Spindle Motor state of above-mentioned optical disc apparatus.
Fig. 3 is the embodiment synoptic diagram that optical disc apparatus provided by the invention is judged the Spindle Motor state.As shown in Figure 3, in the present embodiment, described optical disc apparatus comprises: the light picker (PU) 11 that reads signal on the CD 10; The signal that reads from CD 10 based on described light picker 11 produces the RF chip 12 of RF signal; With the Spindle Motor 24 of High Rotation Speed CD 10, the FG sensor is not set in the Spindle Motor 24; The DC motor 25 that moves radially light picker 11 (be d.c. motor, although step motor has the precedent of using in optical disc apparatus, what use in the present embodiment is the DC motor) by CD 10; The driving chip 16 of drive shaft motor 24 and 25 work of DC motor; And master chip 20, be used for imposing its driving voltage that stops of control by driving chip 16 to Spindle Motor 24, also for detection of the frequency of described RF signal, judge the state of Spindle Motor 24 according to the frequency of the described RF signal that records, when the frequency that detects the RF signal is less than or equal to predetermined threshold value, whether identify the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor 24, and then the stand-by period of the size of the CD that identifies of definite correspondence, after continuing the described stand-by period, determine that Spindle Motor 24 is in halted state.In the specific embodiment, described master chip 20 has been integrated the controller 17 of the whole operation of digital signal processor shown in Figure 1 13 and control optical disc apparatus.
At first, by master chip 20 and driving chip 16, execution in step S101 imposes driving voltage to Spindle Motor, the voltage that described driving voltage stops for the control Spindle Motor.Particularly, when needs stopped Spindle Motor 24 rotation, master chip 20 sent the instruction that stops Spindle Motor 24 to driving chip 16, under the control that drives chip 16, stops operating by imposing a driving voltage drive shaft motor 24.In the present embodiment, driving chip 16 drive shaft motors 24 stops operating, the described driving voltage that applies be drive the maximal value that can export in the loop (for example-7.2V, negative sign represents that this voltage is reverse drive voltages), purpose is to allow Spindle Motor 24 stop within the shortest time.
By light picker 11 and RF chip 12, execution in step S102 reads the RF signal on the CD.
The art personnel know, the data storage method of CD is to come store data with continuous spiral path, and the size of the regional of its track all is the same with density, can guarantee that like this data storage allocation of space is more reasonable.When laser head (light picker) reads on the CD signal, guarantee the accuracy and the stability that read by searching system and focusing system.Searching system makes the laser head can be all the time to the track of quasi-spiral orbit, if laser beam just in time overlaps with the CD track, the error that tracks so is 0.If there is deviation, the photodiode of implementing monitoring finds that two-beam is strong and weak different, and the steady arm on its next door is recovered to signal, and then mobile laser diode just can be positioned orbit centre with laser head.Focusing system makes laser beam accurately penetrate on disc tracks and obtains the strongest signal.When laser beam is returned from CD, need to be through four photodiodes, the signal demand that each photodiode sends forms focus error signal through stack.Only have when this focus error signal is output as zero, focus on just accurately, if focus on inaccurately, obviously just can not successfully read CD.
Need to prove that the signal of RF described in the present embodiment is to process generation based on light picker 11 from the signal of disc reading and by RF chip 12 under the state that searching system is closed.Under normal broadcast state, focusing system and searching system all move, and under non-broadcast state, just no longer the data on the CD have been read, therefore do not need to track, this moment, CD still was in rotation status, and light picker 11 reads but is signal on the trapped orbit, i.e. the 18T signal of the 22T signal of CD CD or DVD CD.What the 22T signal of described CD CD or the 18T signal of DVD CD referred to is exactly the signal same period.So-called same period, signal was exactly that CD must be carved in the beginning of every frame (frame) when being carved into data, and the physical length of each frame all is the same, therefore, had known that the time interval between two same period signals just can have been known rotating speed.The signal of CD CD has 3T, 4T, 5T, 6T, 7T, 8T, 9T, 10T, these several length of 11T, and 22T is exactly two continuous 11T signals.The signal of DVD CD has 3T, 4T, 5T, 6T, 7T, 8T, 9T, 10T, these several length of 11T, 14T, and 18T is exactly the 14T+4T signal.Wherein, T is regular length, for the CD CD, and 1T=0.3 μ m, for the DVD CD, 1T=0.133 μ m.These quantitatively all are definite a kind of specification for the data on the demodulation CD.
Behind the RF signal, master chip 20 is by the state of the frequency judgement Spindle Motor 24 of the described RF signal of detection from disc reading, and the state of described Spindle Motor 24 comprises 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 larger, the frequency of RF signal is just larger, rotating speed is less, the frequency of RF signal is just little, little the arriving to a certain degree of frequency when the RF signal, show that then Spindle Motor 24 stops action and finished, so frequency that can be by considering the RF signal is to judge the state of Spindle Motor 24, for example: Spindle Motor 24 rotating speeds constantly become large, the state of this moment is acceleration mode, and Spindle Motor 24 rotating speeds constantly diminish, and the state of this moment is deceleration regime, become 0 and work as Spindle Motor 24 rotating speeds, the state of this moment is halted state.So when the frequency that detects the RF signal continued to diminish, then the state of described Spindle Motor 24 can be judged as and be in deceleration regime, arrive to a certain degree when the frequency that detects the RF signal is little, then the state of described Spindle Motor 24 can be judged as and be in halted state.
Fig. 4 ideally judges the synoptic diagram that Spindle Motor stops by the frequency that detects the RF signal.In conjunction with Fig. 3 and Fig. 4, before master chip 20 sends Spindle Motors 24 halt instructions to driving chip 16, the driving voltage of Spindle Motor 24 is cyclical variation (sinusoidal waveform), and the RF signal also is corresponding cyclical variation, and this moment, the frequency of RF signal remained unchanged.In this moment of T1, master chip 20 sends Spindle Motor 24 halt instructions to driving chip 16, under the control that drives chip 16, stop by imposing a driving voltage (making Spindle Motor 24 reverse to order about the voltage that it stops) drive shaft motor 24, as shown in Figure 4, the frequency that can see the RF signal this moment continue to diminish (cycle constantly becomes large), until this moment of T2, after the frequency that detects the RF signal reaches certain value, show that Spindle Motor 24 stops action and finishes, namely be judged as Spindle Motor and stop.Therefore, T1 to T2 during this period of time, Spindle Motor 24 is in deceleration regime, the time after T2, Spindle Motor 24 is in halted state.
Certainly, above-mentioned is to judge that by the frequency that detects the RF signal Spindle Motor stops in the ideal case, and under actual conditions, thereby can be because the saturated situation of system occurring so that be difficult in subsequent step judge whether Spindle Motor stops, described system is saturated to be because the function restriction of master chip causes, and is exactly that master chip can not detect the too little RF signal of frequency in simple terms.Therefore, as long as detect the too little RF signal of frequency the saturated situation of system might appear all.
Fig. 5 judges the synoptic diagram that Spindle Motor stops by the frequency that detects the RF signal under the actual conditions.As shown in Figure 5, still in this moment of T1, master chip 20 sends Spindle Motors 24 halt instructions to driving chip 16, under the control that drives chip 16, stops operating by imposing a driving voltage drive shaft motor 24.In the process that Spindle Motor 24 rotating speeds reduce, know the state of Spindle Motor 24 by the frequency that detects the RF signal, the frequency of RF signal is also constantly diminishing in the whole process.But because the restriction of the function of master chip 20, after the frequency of RF signal was reduced to a certain degree, master chip 20 just can't detect the frequency of RF signal, the saturated situation of system namely occurred.Consult Fig. 5, suppose this moment at T3, the saturated situation of system has appearred, can determine in the subsequent step that in order to be implemented in Spindle Motor 24 stops, the threshold value of the frequency of embodiment of the present invention by preseting a RF signal, when the frequency that detects the RF signal is less than or equal to described predefined threshold value (showing that the system of reaching is saturated), and namely is judged as Spindle Motor 24 after continuing the predefined stand-by period and is in halted state.
Certainly, owing to the difference along with disc size, the described predefined stand-by period also is different, therefore, before determining the described stand-by period, also needs to determine first the size of CD.The inventor finds by research, from apply driving voltage to Spindle Motor, different because of the size of CD to the saturated required time of the system that reaches, length during this period of time is also different, therefore can whether identify according to the time that imposes driving voltage to Spindle Motor the size of CD greater than Preset Time.Be execution in step S103, when the frequency of described RF signal is less than or equal to predetermined threshold value, whether identify the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor.
In specific embodiment, can be by the comparatively rational described predetermined threshold value of a large amount of actual testing setups.Here the value representation with the frequency of RF signal is RF, RF=A/B then, wherein B is the numerical value of 16 systems drawing after the RF signal of 20 pairs of receptions of master chip is processed, its expression be time signal (its inverse then represent be frequency signal), this time signal reflection master chip 20 is what of the corresponding clock pulse signal of the RF of one-period signal, particularly, when detecting the RF signal with this clock pulse signal, can the number of the corresponding clock pulse signal of RF signal of one-period be calculated by the counter of master chip 20 inside, such as the time of a clock pulse signal of master chip 20 is 1 μ s, the corresponding clock pulse signal of RF signal of supposing one-period has calculated 100, and the time signal of this moment is 100 μ s so; A is definite value, reflects corresponding relation constant between B and the RF.After Spindle Motor 24 halt instructions are sent, the rotating speed of Spindle Motor 24 constantly diminishes, the value of the B that obtains after master chip 20 is processed can become increasing, the value of RF then constantly diminishes, after the value of B reaches a higher limit, master chip 20 can't record the value of B again, can think that then system is saturated at this moment.In specific embodiment, the higher limit of B can be set as 16 system numerical value 01F4, this moment the RF signal the value RF=A/01F4 of frequency, A/01F4 is described predetermined threshold value.For example: before Spindle Motor 24 halt instructions are sent, the rotating speed of Spindle Motor is 1500 rev/mins, suppose that this moment, corresponding RF value was A/0019, the value of the B that obtains after 0019 master chip 20 when being 1500 rev/mins for the rotating speed of Spindle Motor 24 is processed, after Spindle Motor 24 halt instructions are sent, rotating speed constantly diminishes, it is large that the value of B constantly becomes, the value of RF constantly diminishes, the value of supposing RF becomes A/0060, A/0100 from A/0019, until after becoming A/01F4, think then that system is saturated can not detect.
As 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 that imposes driving voltage to Spindle Motor is T1 to T3 during this period of time.In the specific embodiment, described Preset Time is 340ms, namely when the frequency of described RF signal is less than or equal to predetermined threshold value, if the time that imposes driving voltage to Spindle Motor is during greater than 340ms, then identify CD and be of a size of 12cm, be of a size of 8cm otherwise identify CD.Particularly, can be by a timer be set, the beginning timing in impose driving voltage to Spindle Motor of described timer finishes timing when being less than or equal to predetermined threshold value to the frequency that detects described RF signal, just can judge the size of CD based on the result of timing.
After identifying the size of CD, execution in step S104 determines stand-by period of the size of the CD that correspondence identifies.Particularly, the described stand-by period is different except the size because of CD, also different different in the residing position of CD because of light picker, when light picker is in the border (also can be described as the reference position in data of optical disk zone) of data of optical disk zone and ingress area, the described stand-by period was the first stand-by period, at this moment, the stand-by period of determining the size of the CD that correspondence identifies comprises: based on the rotating speed of described Spindle Motor and the first stand-by period that enters corresponding relation between the halted state required time and determine the size of the corresponding CD that identifies.
Described the first stand-by period can be set by the rotating speed of setting up described Spindle Motor and the model that enters corresponding relation between the halted state required time.Specifically obtain rotating speed and the time response of employed Spindle Motor by a large amount of actual measurements, being Spindle Motor need to repeatedly measurement result how long to stopping operating from certain rotating speed, set up the rotating speed of Spindle Motor and enter the model of corresponding relation between the halted state required time by the mode of match, the corresponding relation here may be linear relationship, also may be nonlinear relationship.
In the present embodiment, what obtain by actual measurement is the model of linear relationship.And when the frequency of RF signal is less than or equal to predetermined threshold value A/01F4 (when reaching described predetermined threshold value A/01F4, be that system is saturated), the rotating speed of CD can obtain the result by actual measurement for this moment, no matter disc size is 8cm or 12cm, when light picker is in the border of data of optical disk zone and ingress area, the rotating speed of the Spindle Motor 24 that records is approximately 400～500 rev/mins, thus can according to disc size and this moment Spindle Motor 24 rotating speed and time response (stopping operating the required time) judge how long should wait for, namely 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, allowing so principal axis motor rotation speed reach needed the first stand-by period of 0rpm from 400rpm is exactly (0-400)/(1.3) ≈ 307ms, allowing principal axis motor rotation speed reach needed the first stand-by period of 0rpm from 500rpm is exactly (0-500)/(1.3) ≈ 384ms, and the scope that therefore described the first stand-by period is set should be 307～384ms.And because the quality of 8cm dish is low weight, stop than being easier to, that is to say that its slope can be larger with respect to the 12cm dish, the slope that obtains after tested the linear relationship model is-4.12rpm/ms, thus, when the frequency of RF signal equals predetermined threshold value A/01F4 (system is saturated), the rotating speed of described Spindle Motor is 400～500rpm, allowing so principal axis motor rotation speed reach needed the first stand-by period of 0rpm from 400rpm is exactly (0-400)/(4.12) ≈ 97ms, allowing principal axis motor rotation speed reach needed the first stand-by period of 0rpm from 500rpm is exactly (0-500)/(4.12) ≈ 121ms, and the scope that described the first stand-by period of this moment is set should be 97～121ms.In the specific embodiment, equally can be by the timing of above-mentioned timer realization to described the first stand-by period, when the frequency of RF signal reaches predetermined threshold value, just start this timer and carry out timing, after reaching described the first stand-by period, timing finishes timing, can finish this moment by producing trigger pip prompting timing, thereby determine that the Spindle Motor state is halted state.
In addition, when light picker is in the data of optical disk zone when (not comprising its reference position herein), the described stand-by period was the second stand-by period, the stand-by period of determining at this moment the size of the CD that correspondence identifies also comprises: based on the first radius, the second radius and described the first stand-by period determined for the second stand-by period, radius (the CD center of circle is to the distance of light picker track of living in) when described the first radius light picker when determining described the first stand-by period is in the border of data of optical disk zone and ingress area, described the second radius light picker when determining described the second stand-by period is in the radius of data of optical disk when regional.
When light picker is in the data of optical disk zone, before imposing driving voltage to Spindle Motor, also comprise: read light picker and be in the data of optical disk current location information in when zone, then close searching system, described the second radius obtains by described current location information.Described current location information is different for different optical disc types, when described CD is the DVD CD, then reads light picker and refers to the sector auxiliary information (ID) that reads light picker current location on CD at the current location information on the CD; If described CD is the CD CD, then reads light picker and refer at the current location information on the CD and read the absolute time information (Sub-Q) that is recorded on the described CD.Need to prove, before imposing driving voltage to Spindle Motor, can preset this driving voltage, after finishing default driving voltage, searching system is in closed condition (can't read ID/Sub-Q this moment) before, need to read ID/Sub-Q, for the ID/Sub-Q that guarantees to read is the ID/Sub-Q of searching system turn-off transient really, can only close at once searching system after running through ID/Sub-Q, after this Spindle Motor reduces speed now under the applying of driving voltage.
Usually, regardless of the size of CD, the value of described the first radius is known, and namely for the CD CD, the first radius is 25mm, and for the DVD CD, the first radius is 24mm.In addition, described the second stand-by period that light picker is on any position (not comprising its reference position) in data of optical disk zone is directly proportional with the rotating speed (angular velocity omega) of CD, again because ω=v/r, wherein v is linear velocity, r is described the second radius, therefore, the second stand-by period was directly proportional with v/r.In fact the linear velocity of CD is constant, causes for the second stand-by period be directly proportional with 1/r.The pass of described the first stand-by period when as a result, light picker is in the border that described the second stand-by period on the optional position in data of optical disk zone and light picker be in data of optical disk zone and ingress area is:
Second the stand-by period=(the first radius * the first stand-by period)/the second radius (1)
Wherein, the second radius can be expressed as:
The second radius=the first radius+track pitch * physical track number (2)
For CD, track pitch is known constant, and for the second stand-by period, and if only if physical track number provides, and just can calculate by formula (1), (2).
And described physical track number is can derive by the ID/Sub-Q that light picker reads to obtain, concrete derivation dawn known to those skilled in the art, do not repeat them here.
Therefore, after measuring described the first stand-by period, just can draw light picker according to the first stand-by period, the first radius, the second radius and be in data of optical disk described second stand-by period in when zone.
After the stand-by period of the size of determining the CD that correspondence identifies, execution in step S105 after the lasting described stand-by period, determines that described Spindle Motor state is halted state, stops to apply described driving voltage.
As shown in Figure 5, this moment Spindle Motor 24 of T1 begins to enter deceleration regime, this frequency that constantly detects the RF signal of T3 equals predetermined threshold value (system is saturated), according to the default stand-by period wait for to T4 this constantly, it is the default stand-by period of T4=T3+, this constantly is judged to be T4 Spindle Motor 24 and enters halted state, and stop to apply described driving voltage this moment, namely stops to Spindle Motor 24 power supplies (input voltage of Spindle Motor 24 is 0).Therefore, T1 to T4 during this period of time, Spindle Motor 24 is in deceleration regime, wherein, T1 to T3 can detect the frequency of RF signal during this period of time, T3 to T4 during this period of time (stand-by period) can not detect the frequency of RF signal, time after T4, Spindle Motor 24 is in halted state.
Need to prove, above-mentioned actual measurement refers to the research work done in order to set out comparatively rational described predetermined threshold value and the first stand-by period, do not refer to the implementation of the method that the described judgement Spindle Motor of embodiment of the present invention stops, owing to do not dispose FG sensor rotation speed monitoring device in the optical disc apparatus of the method that the described judgement Spindle Motor of enforcement stops, how many concrete rotating speeds that therefore can not obtain certain moment Spindle Motor is, but in actual measurement, can be by FG sensor rotation speed monitoring device be set at optical disc apparatus, thus detect certain constantly the concrete rotating speed of Spindle Motor what are.
In addition, the A here also be can be by actual measurement as a result indirect calculation out.A should be certain value in theory, can go out concrete numerical value by looking for a method indirect calculation, for example: how many B that finds out first among the formula RF=A/B corresponding when the rotating speed of Spindle Motor is 1500 rev/mins (frequency is 25Hz) is, when 1200 rev/mins (frequency is 20Hz) among the corresponding formula RF=A/B B what are, ... by that analogy, until when finding out 200 rev/mins among the corresponding formula RF=A/B B what are, by repeatedly measure (getting rid of error) as far as possible, draw at last the concrete numerical value of A.In the present embodiment, the concrete numerical value that the result by actual measurement draws A indirectly is 15E0 (16 system number).Need to prove, here the concrete numerical value of the A that draws is a mean value of obtaining in order conveniently to look for a little and to calculate in the process of actual measurement, in fact the value of calculating under different rotating speeds is different, for example: 1500 rev/mins of values that draw A correspond to 16D4, and 450 rev/mins of values that draw A correspond to EC7.Although averaging, A can have certain error, but when the actual set threshold value, mainly consider to set in the situation when rotating speed reaches 400～500 rev/mins, so this error does not affect for whether reaching the saturated judgement of system, does not just affect the judgement that Spindle Motor stops yet.
Based on the method for above-mentioned judgement Spindle Motor state, embodiment of the present invention also provides a kind of optical disc apparatus.Fig. 6 is the structural representation of the optical disc apparatus that provides of embodiment of the present invention, and as shown in Figure 6, described optical disc apparatus comprises:
Driving voltage applying unit 201 is used for imposing driving voltage to Spindle Motor, the voltage that described driving voltage stops for the control Spindle Motor;
Reading unit 202 is used for reading the RF signal on the CD;
Size recognition unit 203 is used for when the frequency of described RF signal is less than or equal to predetermined threshold value, whether identifies the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor; Described size recognition unit 203 is connected with described driving voltage applying unit 201, reading unit 202;
Time determining unit 204 is for the stand-by period of the size of determining the CD that correspondence identifies; Described time determining unit 204 is connected with described size recognition unit 203; Described time determining unit 204 can comprise the first determining unit, is used for based on the rotating speed of described Spindle Motor and the first stand-by period that enters corresponding relation between the halted state required time and determine the size of the corresponding CD that identifies; When light picker was in the border of data of optical disk zone and ingress area, the described stand-by period was the first stand-by period; Described time determining unit 204 also can comprise the second determining unit, be used for determining for the second stand-by period based on the first radius, the second radius and described the first stand-by period, radius when described the first radius light picker when determining described the first stand-by period is in the border of data of optical disk zone and ingress area, described the second radius light picker when determining described the second stand-by period is in the radius of data of optical disk when regional; When light picker was in the data of optical disk zone, the described stand-by period was the second stand-by period;
Status determining unit 205 is used for determining that described Spindle Motor state is halted state after continuing the described stand-by period, and controls described driving voltage applying unit 201 and stop to apply described driving voltage; Described status determining unit 205 is connected with described time determining unit 204, driving voltage applying unit 201.
In the specific embodiment, in conjunction with Fig. 3, described driving voltage applying unit 201 is specifically as follows and drives chip 16, and described reading unit 202 can comprise be used to the light picker 11 that reads signal on the CD and the RF chip 12 that produces described RF signal based on the signal that described light picker 11 reads from CD.Described size recognition unit 203, time determining unit 204 and status determining unit 205 are integrated in the master chip 20 of described optical disc apparatus.
Can with reference to the method for the judgement Spindle Motor state of above-mentioned optical disc apparatus, not repeat them here about the implementation of described optical disc apparatus.
To sum up, the method for the optical disc apparatus that embodiment of the present invention provides and judgement Spindle Motor state thereof has following beneficial effect at least:
To Spindle Motor apply control its driving voltage that stops after, judge the state of Spindle Motor by the frequency that detects the RF signal that reads from CD, when the frequency that detects the RF signal is less than or equal to predetermined threshold value, whether identify the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor, and then the stand-by period of the size of the CD that identifies of definite correspondence, after continuing the described stand-by period, just can determine that the Spindle Motor state is halted state, thereby can be implemented in the situation without the FG signal, just can judge easily Spindle Motor and whether be in halted state, owing to saved for generation of rotation speed monitoring device (FG sensor) and the detection loop of FG signal to detect principal axis motor rotation speed, greatly reduced the cost of optical disc apparatus.
Identifying in the situation of disc size, by determining the first stand-by period when light picker is in the border of data of optical disk zone and ingress area, and determine when light picker based on described the first stand-by period and to be in data of optical disk second stand-by period in when zone, realize thus determining the corresponding stand-by period according to light picker at the diverse location of CD, can judge more accurately Spindle Motor and whether be in halted state.
Although the present invention with preferred embodiment openly as above; but it is not to limit the present invention; any those skilled in the art without departing from the spirit and scope of the present invention; can utilize method and the technology contents of above-mentioned announcement that technical solution of the present invention is made possible change and modification; therefore; every content that does not break away from technical solution of the present invention; to any simple modification, equivalent variations and modification that above embodiment does, all belong to the protection domain of technical solution of the present invention according to technical spirit of the present invention.
Claims (25)
1. the method for the judgement Spindle Motor state of an optical disc apparatus is characterized in that, comprising:
Impose driving voltage to Spindle Motor, the voltage that described driving voltage stops for the control Spindle Motor;
Read the RF signal on the CD;
When the frequency of described RF signal is less than or equal to predetermined threshold value, whether identify the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor;
The stand-by period of the size of the CD that definite correspondence identifies;
After continuing the described stand-by period, determine that described Spindle Motor state is halted state, stop to apply described driving voltage.
2. the method for judgement Spindle Motor state according to claim 1 is characterized in that, when the frequency of described RF signal continues to diminish, determines that described Spindle Motor state is deceleration regime.
3. the method for judgement Spindle Motor state according to claim 1, it is characterized in that, determine that the stand-by period of the size of the CD that correspondence identifies comprises: based on the rotating speed of described Spindle Motor and the first stand-by period that enters corresponding relation between the halted state required time and determine the size of the corresponding CD that identifies; When light picker was in the border of data of optical disk zone and ingress area, the described stand-by period was the first stand-by period.
4. the method for judgement Spindle Motor state according to claim 3 is characterized in that, when the frequency of described RF signal reached predetermined threshold value, the rotating speed of described Spindle Motor was 400～500 rev/mins.
5. the method for judgement Spindle Motor state according to claim 4 is characterized in that, the CD that identifies is of a size of 12cm, and described the first stand-by period is 307～384ms.
6. the method for judgement Spindle Motor state according to claim 4 is characterized in that, the CD that identifies is of a size of 8cm, and described the first stand-by period is 97～121ms.
7. the method for judgement Spindle Motor state according to claim 3, it is characterized in that, the stand-by period of the size of the CD that definite correspondence identifies also comprises: determined for the second stand-by period based on the first radius, the second radius and described the first stand-by period, radius when described the first radius light picker when determining described the first stand-by period is in the border of data of optical disk zone and ingress area, described the second radius light picker when determining described the second stand-by period is in the radius of data of optical disk when regional; When light picker was in the data of optical disk zone, the described stand-by period was the second stand-by period.
8. the method for judgement Spindle Motor state according to claim 7, it is characterized in that, before imposing driving voltage to Spindle Motor, also comprise: read light picker and be in the data of optical disk current location information in when zone, then close searching system, described the second radius obtains by described current location information.
9. the method for judgement Spindle Motor state according to claim 8, it is characterized in that, described CD is the DVD CD, and the described light picker that reads comprises at the current location information on the described CD: the sector auxiliary information that reads light picker current location on described CD.
10. the method for judgement Spindle Motor state according to claim 8 is characterized in that, described CD is the CD CD, and the described light picker that reads comprises at the current location information on the described CD: read the absolute time information that is recorded on the described CD.
11. the method for judgement Spindle Motor state according to claim 1, it is characterized in that described Preset Time is 340ms, if the time that imposes driving voltage to Spindle Motor is during greater than 340ms, then identify CD and be of a size of 12cm, be of a size of 8cm otherwise identify CD.
12. the method for judgement Spindle Motor state according to claim 1 is characterized in that, described RF signal is to read under the state that searching system is closed.
13. an optical disc apparatus is characterized in that, comprising:
The driving voltage applying unit is used for imposing driving voltage to Spindle Motor, the voltage that described driving voltage stops for the control Spindle Motor;
Reading unit is used for reading the RF signal on the CD;
The size recognition unit is used for when the frequency of described RF signal is less than or equal to predetermined threshold value, whether identifies the size of CD greater than Preset Time according to the time that imposes driving voltage to Spindle Motor;
The time determining unit is for the stand-by period of the size of determining the CD that correspondence identifies;
Status determining unit is used for determining that described Spindle Motor state is halted state after continuing the described stand-by period, and controls described driving voltage applying unit and stop to apply described driving voltage.
14. optical disc apparatus according to claim 13 is characterized in that, described reading unit comprises be used to the light picker that reads signal on the CD and the RF chip that produces described RF signal based on the signal that described light picker reads from CD.
15. optical disc apparatus according to claim 13 is characterized in that, described size recognition unit, time determining 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 characterized in that, described time determining unit comprises the first determining unit, is used for based on the rotating speed of described Spindle Motor and the first stand-by period that enters corresponding relation between the halted state required time and determine the size of the corresponding CD that identifies; When light picker was in the border of data of optical disk zone and ingress area, the described stand-by period was the first stand-by period.
17. optical disc apparatus according to claim 16 is characterized in that, when the frequency of described RF signal reached predetermined threshold value, the rotating speed of described Spindle Motor was 400～500 rev/mins.
18. optical disc apparatus according to claim 17 is characterized in that, the CD that described size recognition unit identifies is of a size of 12cm, and described the first stand-by period is 307～384ms.
19. optical disc apparatus according to claim 17 is characterized in that, the CD that described size recognition unit identifies is of a size of 8cm, and described the first stand-by period is 97～121ms.
20. optical disc apparatus according to claim 16, it is characterized in that, described time determining unit also comprises the second determining unit, be used for determining for the second stand-by period based on the first radius, the second radius and described the first stand-by period, radius when described the first radius light picker when determining described the first stand-by period is in the border of data of optical disk zone and ingress area, described the second radius light picker when determining described the second stand-by period is in the radius of data of optical disk when regional; When light picker was in the data of optical disk zone, the described stand-by period was the second stand-by period.
21. optical disc apparatus according to claim 20, it is characterized in that, before described driving voltage applying unit imposes driving voltage to Spindle Motor, described reading unit also reads light picker at the current location information in described data of optical disk zone, then close searching system, described the second radius obtains by described current location information.
22. optical disc apparatus according to claim 21, it is characterized in that, described CD is the DVD CD, and described reading unit reads light picker and comprises at the current location information on the described CD: the sector auxiliary information that reads light picker current location on described CD.
23. optical disc apparatus according to claim 21 is characterized in that, described CD is the CD CD, and described reading unit reads light picker and comprises at the current location information on the described CD: read the absolute time information that is recorded on the described CD.
24. optical disc apparatus according to claim 13, it is characterized in that, described Preset Time is 340ms, if described driving voltage applying unit imposes time from driving voltage to Spindle Motor is during greater than 340ms, then described size recognition unit identifies CD and is of a size of 12cm, is of a size of 8cm otherwise identify CD.
25. optical disc apparatus according to claim 13 is characterized in that, described RF signal is that described reading unit reads under the state that searching system is closed.
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