Mediatek Corporation

Mediatek Incorporation

Hsiang-Ji Hsieh

Yu-Hsin Lin

Ping-Ying Wang

Meng-Ta Yang

Chih-Yuan Chen

Gwo-Huei Wu

Hsueh-Kun Liao

Chao-ming Huang

Chih-Chin Hsu

Yu-Kai Chou

A method and an apparatus for deciding a spherical aberration compensation (SAC) value for an optical storage medium are provided. The optical storage medium comprises at least one recording layer and a cover layer. The SAC value is suitable for a selected one of the at least one recording layer. First, a focus search on the optical storage medium is performed to derive a focus error (FE) signal in response to a testing SAC value. Then, a center level and a center basis corresponding to the testing SAC value according to the FE signal is determined. The SAC value according to the center level, the center basis, and the testing SAC value is also determined. When the center level and the center basis are equal, the SAC value is determined to be the testing SAC value.

Method and apparatus for deciding spherical aberration compensation value

A recording apparatus for optical data includes a photo detection IC for producing a plurality of phase signals; a plurality of sample/hold (S/H) circuits electrically connected to the photo detection IC; a plurality of limiter circuits electrically connected to the photo detection IC; a channel signal generator connected to the S/H circuits; and a level shift circuit connected to an output of the channel signal generator. The recording apparatus for optical data prevents the interference of servo signal during high speed operation and ensures normal operation of S/H circuits thereof.

Recording apparatus for optical data

An optical disc drive includes a servo system and a system behavior detection module. The system behavior detection module includes a controller and a signal feeding unit coupled to the controller and the servo system. The controller is operable in a detection mode and in a normal operation mode. In the detection mode, the controller enables the signal feeding unit so as to introduce an exciting signal into the servo system. In the normal operation mode, the controller disables the signal feeding unit so as to inhibit introduction of the exciting signal into the servo system.

Optical disc drive with a system behavior detection module

A phase locked loop capable of compensating for errors caused by cycle slips. The phase locked loop includes a phase detection unit for generating a phase error signal; a loop filter for filtering the phase error signal and generating a first control signal; a cycle slip detector for detecting whether a cycle slip has occurred according to the phase error signal and generating a slip indication signal; a toggling unit for toggling the selection between a first value and a second value as a compensation signal according to the slip indication signal; an accumulator for accumulating the compensation signal and generating a second control signal; an adder for adding the first control signal and the second control signal and generating a third control signal; and a controllable oscillator for generating the output clock at a frequency based on the third control signal.

Phase locked loop having cycle slip detector capable of compensating for errors caused by cycle slips

A method for controlling an optical drive to record data onto a disc. The optical recorder has a pick up head for emitting laser onto the disc to record data onto the disc. The method includes adjusting a write power and a write strategy of the optical drive according to a linear velocity of the disc when passing by the pick up head.

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Taipei Hsien, Taiwan

Hsiang-Ji Hsieh