Source: http://www.google.com/patents/US7911891?dq=6,621,746
Timestamp: 2014-03-16 13:47:41
Document Index: 467196277

Matched Legal Cases: ['Application No. 60', 'Application No. 60', 'Application No. 60', 'Application No. 60', 'Application No. 60', 'Application No. 60', 'Application No. 60', 'Application No. 60', 'Application No. 60', 'Application No. 60']

Patent US7911891 - Apparatus for controling servo signal gains of an optical disc drive and ... - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsThe invention provides an apparatus for controlling servo signal gains of an optical disc drive. The apparatus adjusts the gains of a plurality of servo signals controlling a servo system of the optical disc drive according to a closed-loop mode or a state-reloading mode whenever the optical disk drive...http://www.google.com/patents/US7911891?utm_source=gb-gplus-sharePatent US7911891 - Apparatus for controling servo signal gains of an optical disc drive and method of sameAdvanced Patent SearchPublication numberUS7911891 B2Publication typeGrantApplication numberUS 11/758,082Publication dateMar 22, 2011Filing dateJun 5, 2007Priority dateJun 5, 2006Also published asUS8089834, US20070280066, US20110110205Publication number11758082, 758082, US 7911891 B2, US 7911891B2, US-B2-7911891, US7911891 B2, US7911891B2InventorsChia-Wei Liao, Chih-Ching Chen, Yuh Cheng, Ming-Jiou Yu, Kuo-Jung Lan, Chun-Yu Lin, Shu-Hung ChouOriginal AssigneeMediatek Inc.Export CitationBiBTeX, EndNote, RefManPatent Citations (49), Non-Patent Citations (8), Referenced by (2), Classifications (6), Legal Events (1) External Links: USPTO, USPTO Assignment, EspacenetApparatus for controling servo signal gains of an optical disc drive and method of sameUS 7911891 B2Abstract The invention provides an apparatus for controlling servo signal gains of an optical disc drive. The apparatus adjusts the gains of a plurality of servo signals controlling a servo system of the optical disc drive according to a closed-loop mode or a state-reloading mode whenever the optical disk drive encounters an operating state transition. In closed-loop mode, at least one AGC loop of the apparatus compensates the gains of the servo signals with a selectable bandwidth during a specific period after the operating state transition to accelerate the convergence of the servo signals. In state-reloading mode, at least one AGC loop of the apparatus reloads the previously saved convergence values or pre-determined values as the initial values according to the current operating state immediately after the operating state transition to accelerate the convergence of the servo signals.
CROSS REFERENCE TO RELATED APPILCATIONS This application claims the benefit of U.S. Provisional Application No. 60/803,874, filed Jun. 5, 2006, U.S. Provisional Application No. 60/803,875, filed Jun. 5, 2006, U.S. Provisional Application No. 60/803,887, filed Jun. 5, 2006, U.S. Provisional Application No. 60/810,991, filed Jun. 5, 2006, U.S. Provisional Application No. 60/810,972, filed Jun. 5, 2006, U.S. Provisional Application No. 60/810,989, filed Jun. 5, 2006, U.S. Provisional Application No. 60/811,031, filed Jun. 5, 2006, U.S. Provisional Application No. 60/811,017, filed Jun. 5, 2006, U.S. Provisional Application No. 60/810,990, filed Jun. 5, 2006, and U.S. Provisional Application No. 60/810,898, filed Jun. 5, 2006. Each of these provisional applications is hereby incorporated by reference.
BRIEF SUMMARY OF THE INVENTION An apparatus for controlling servo signal gains of an optical disc drive is provided. The apparatus adjusts the gains of a plurality of servo signals controlling a servo system of the optical disc drive according to a closed-loop mode or a state-reloading mode whenever the optical disk drive encounters an operating state transition, in which the reflectivity of an optical disc is changed. In closed-loop mode, at least one AGC loop determining the gains of the servo signals is compensated with a selectable bandwidth during a specific period after the operating state transition to accelerate the convergence of the servo signals. Or in state reloading mode, previously saved convergence values or pre-determined values determining the most possible gains of the servo signals are immediately reloaded to be the initial values of at least one AGC loop after the operating state transition to accelerate the convergence of the servo signals. After reloading of this previously saved convergence values or pre-determined values as the initial values of AGC loops, the requirement for the bandwidth of AGC loops can be not so high.
FIG. 12 shows converging processes of the AGC loop in closd-loop mode and state-reload mode. Each of the times T1�T5 corresponds to an operating state transition as in FIG. 11. The loop ratio 1 shows the converging process of the AGC loop ratio in closed-loop mode only, and the loop ratio 2 shows the converging process of the AGC loop ratio in the combination of state-reload and closed-loop mode. The Bandwidth of AGC loop is selectable. Because the loop ratio 1 could be accelerated with a high bandwidth during a specific period after the operating state transition, rapid convergence of the loop ratio 1 could be attained. Additionally, because previously saved convergence values of the loop ratio or any pre-determined values are immediately assigned to be as the initial values of the loop ratio 2, the loop ratio 2 immediately converges to the correct level to accelerate the convergence of the servo signals.
P w P p ⁢ ⁢ k = Δ ⁢ ⁢ I 1 ′ Δ ⁢ ⁢ I 1 = ( Δ ⁢ ⁢ I 1 ″ + Δ w ′ ) ( Δ ⁢ ⁢ I 1 ″ + Δ ⁢ ⁢ I w ′ + Δ ⁢ ⁢ I p ⁢ ⁢ k ′ ) Equation ⁢ ⁢ ( 1 ) In Equation (1), the parameter ΔI1″ is meant to be an amount of current shown in FIG. 21 and can be calculated according to the slope Gw and target read power level Pr, and the amount of currentΔIw′ can be derived according to the driving signal Sw′. Since the target peak power level Ppk and the target write power level Pw are known and the amounts of current ΔI1″ and ΔIw′ are calculated, the amount of current ΔIpk′ can also be calculated by Equation (1). That is, the peak power control value can be derived if the write power control value and an adjusting value corresponding to the amount of current ΔI1″ are determined, since a conversion relation between driving signals corresponding to the above-mentioned amounts of current and control values is almost linear. Thus, the adjusting value corresponding to the amount of currentΔI1″ can be calculated according to the amount of current ΔI1″ and the conversion relation between the driving signals and control values. The peak power control value is determined once the adjusting value is calculated, and then the APC system 2502 can control the actual peak power level at the target peak power level Ppk correctly according to the peak power control value. In this embodiment, the peak power control value is equal to the value of the write power control value plus the determined adjusting value. Even though a required driving current passing through the LD D1 may be a little different due to the above-mentioned reasons (e.g. a change of the temperature of the LD D1 or the other factors), the APC system 2502 can still control the actual peak power level at the target peak power level Ppk effectively by deriving a new adjusting value according to the target read power P r, and a new calculated slope (usually, when the required driving current is different, there is also some possibility that the write power control value is changed and therefore it is necessary to calculate a new slope).
14K 1 KHz
18K 2 KHz
16K Bypass
18K Bypass
VMAX=max (CUR_MAX, PRE_MAX) (1)VMIN=min (CUR_MIN, PRE_MIN) (2)
VMAX=max (PRE_MAX1, PRE_MAX2, . . . , PRE_MAXn−1, CUR_MAX) (3)VMIN=max (PRE_MIN1, PRE_MIN2, . . . , PRE_MINn−1, CUR_MIN) (4)
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS5212675 *Jan 23, 1992May 18, 1993Pioneer Electronic CorporationApparatus for detecting position of light spotUS5699334Jan 22, 1996Dec 16, 1997Matsushita Electric Industrial Co., Ltd.Control devices for optical disk based on driving signal saturationUS5703848 *Apr 5, 1994Dec 30, 1997Hewlett-Packard CompanyOff track detection system for ruggedized optical disk driveUS5768227 *Sep 8, 1997Jun 16, 1998Canon Kabushiki KaishaOptical information recording and or reproducing apparatus and method for irradiating a recording medium having a plurality of information tracksUS5805715Jun 29, 1994Sep 8, 1998Samsung Electronics Co., Ltd.Method and apparatus for compensating multi-resolution linear distortionUS5915028Sep 8, 1995Jun 22, 1999Robert Bosch GmbhAmplitude demodulatorUS6091678Jan 5, 1998Jul 18, 2000Hitachi Video & Information Systems, Inc.Method and apparatus for detecting position of alternated land and groove of information recording mediumUS6392967Sep 11, 1998May 21, 2002Sony Precision Engineering Center (S) Pte. Ltd.Apparatus for measuring characteristics of optical disc systems and methodUS6424687Mar 15, 1999Jul 23, 2002Cirrus Logic, Inc.Method and device for alignment of audio data frames using interpolation and decimationUS6590843Jun 1, 1999Jul 8, 2003Texas Instruments IncorporatedDVD radial runout cancellation with self-calibrationUS6731586Mar 26, 2001May 4, 2004Samsung Electronics Co., Ltd.Apparatus for and method of controlling auto laser diode powerUS6735162Jun 13, 2001May 11, 2004Lsi Logic CorporationApparatus and method providing a mirror averaging function to generate a mirror signal from optical data on an optical discUS6762982May 23, 2001Jul 13, 2004Lsi Logic CorporationApparatus and method of interrupt detection in an optical disc environmentUS6834035Sep 29, 2000Dec 21, 2004Matsushita Electric Industrial Co. Ltd.Digital reproduced signal processing deviceUS6891787Aug 22, 2000May 10, 2005Sanyo Electric Co., Ltd.Apparatus for recording/reproducing signal on/from optical diskUS6898223Feb 28, 2002May 24, 2005Samsung Electronics Co., Ltd.Apparatus for and method of controlling output of a laser diodeUS6967906May 16, 2003Nov 22, 2005Samsung Electronics Co., Ltd.Circuit and method for detecting mirror signal for optical disc apparatusUS7035187Dec 13, 2002Apr 25, 2006Via Technologies, Inc.Apparatus and method for generating RFZC signal for optical systemsUS7474235Jun 5, 2007Jan 6, 2009Mediatek Inc.Automatic power control system for optical disc drive and method thereofUS20010006494Dec 22, 2000Jul 5, 2001Sang On ParkApparatus and method for controlling tracking for optical recording/reproducing apparatusUS20010024459Mar 26, 2001Sep 27, 2001Seo Jin-GyoApparatus for and method of controlling auto laser diode powerUS20020196717 *Apr 1, 2002Dec 26, 2002Naruhiro MasuiSignal processing method and signal processing apparatusUS20030021208Jul 25, 2002Jan 30, 2003Youichi OguraDigital data reproduction apparatusUS20030185260Dec 17, 2002Oct 2, 2003Samsung Electronics Co., Ltd.Laser diode driver and driving method for controlling auto laser power, optical pickup device, and optical recording/reproducing apparatus using the sameUS20040190397 *Sep 17, 2003Sep 30, 2004Matsushita Electric Industrial Co., Ltd.Apparatus and method for tracking controlUS20040233826May 18, 2004Nov 25, 2004Akihiro SuganoLaser power control device, information recording apparatus, optical disk apparatus, laser power source drive current value determining method, information recording method, optical disk recording methodUS20040252599May 20, 2004Dec 16, 2004Sanyo Electric Co, Ltd.Offset adjusting circuit for optical disc and offset adjusting methodUS20040257946Nov 7, 2003Dec 23, 2004Chao-Ming HuangDynamic radio frequency ripple signal compensator of an optical storage systemUS20050006882Jul 10, 2003Jan 13, 2005Yunzhang WangAir bag and method for making an air bagUS20050185559Feb 1, 2005Aug 25, 2005Kabushiki Kaisha ToshibaOptical disk device, reproduction method of information on optical disk, and optical diskUS20050270918May 27, 2005Dec 8, 2005Kuang-Yu YenOptical disc drive capable of generating digital servo control signals and method thereofUS20050280569Jun 14, 2005Dec 22, 2005Samsung Electronics Co., Ltd.Analog baseband processor and method of processing analog baseband for use in multimode communication systemUS20050281300Aug 15, 2004Dec 22, 2005Yung-Chih LiLaser power controller and method for performing auto power controlUS20060193053 *Jan 30, 2006Aug 31, 2006Tdk CorporationDiffraction grating, light-receiving element, and optical head and optical recording/reproducing apparatus utilizing themUS20060267825Feb 28, 2006Nov 30, 2006Sanyo Electric Co., Ltd.High frequency compensator and reproducing deviceUS20070019772Sep 29, 2006Jan 25, 2007Applied Micro Circuits CorporationTimeshared jitter attenuator in multi-channel mapping applicationsUS20070047635Aug 24, 2005Mar 1, 2007Stojanovic Vladimir MSignaling system with data correlation detectionUS20070070853Mar 30, 2005Mar 29, 2007Kenji KoishiInformation recording method, information recording apparatus and information recording mediumUS20070133831Sep 5, 2006Jun 14, 2007Samsung Electronics Co., Ltd.Apparatus and method of reproducing virtual sound of two channelsUS20080033695Oct 17, 2005Feb 7, 2008Nsk LtdAbnormality Diagnosing System For Mechanical EquipmentUS20080219116Jun 17, 2005Sep 11, 2008Kenji NarumiOptical Information Recording Method, Optical Information Recording Apparatus, and Optical Information Recording MediumUSRE40822Aug 23, 2007Jul 7, 2009Ronnie LaiCalibration method for slice level of zero cross signal and method of producing track-crossing signalCN1319841AMar 23, 2001Oct 31, 2001三星电子株式会社Device and method for automatically controlling laser diode powerCN1402231ASep 29, 2002Mar 12, 2003威盛电子股份有限公司Read-write head output power control method for CD machineCN1448929AOct 10, 2002Oct 15, 2003三星电子株式会社Laser diode driver, optical pickup device, and optical recording/reproducing apparatus using the sameCN1573973AMay 10, 2004Feb 2, 2005三洋电机株式会社Offset adjusting circuit for optical disc and offset adjusting method, integrated circuit, optical discCN1604208ASep 15, 2004Apr 6, 2005株式会社东芝Optical disk apparatus and laser control methodTW227017B Title not availableTW476935B Title not available* Cited by examinerNon-Patent CitationsReference1English language translation of abstract of CN 1319841 (published Oct. 31, 2001).2English language translation of abstract of CN 1402231 (published Mar. 12, 2003).3English language translation of abstract of CN 1448929 (published Oct. 15, 2003).4English language translation of abstract of CN 1573973 (published Feb. 2, 2005).5English language translation of abstract of CN 1604208 (published Apr. 6, 2005).6English language translation of abstract of TW 227017 (published Jan. 21, 2005).7English language translation of abstract of TW 476935 (published Feb. 21, 2002).8Office Action of U.S. Appl. No. 11/758,119, dated May 28, 2008.Referenced byCiting PatentFiling datePublication dateApplicantTitleUS8248289 *Aug 25, 2010Aug 21, 2012Texas Instruments IncorporatedPower and area efficient interleaved ADCUS20120050081 *Aug 25, 2010Mar 1, 2012Texas Instruments IncorporatedPower and area efficient interleaved adc* Cited by examinerClassifications U.S. Classification369/44.29, 369/44.26International ClassificationG11B7/00Cooperative ClassificationG11B7/0941, G11B7/0903European ClassificationG11B7/09KLegal EventsDateCodeEventDescriptionJun 5, 2007ASAssignmentOwner name: MEDIATEK INC., TAIWANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LIAO, CHIA-WEI;CHEN, CHIH-CHING;CHENG, YUH;AND OTHERS;REEL/FRAME:019379/0711;SIGNING DATES FROM 20070312 TO 20070319Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LIAO, CHIA-WEI;CHEN, CHIH-CHING;CHENG, YUH;AND OTHERS;SIGNING DATES FROM 20070312 TO 20070319;REEL/FRAME:019379/0711RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google