Mediatek Corporation

Industrial Technology Research Institute

Mediatek Incorporation

Ming-Jiou Yu

Chih-Ching Chen

Kuo-Jung Lan

Shu-Hung Chou

Chia-Wei Liao

Bing-Yu Hsieh

Yuh Cheng

Chun-Yu Lin

Jong-Woei Chen

Chi-Pei Huang

Chih-chung Wu

Yu-Hsuan Lin

Kuan-Hua Chao

Chia-Hua Chou

Yen-Lin Chen

Shiue-Shin Liu

Li-Te Kuo

Hung-I Chen

Meng-Hsueh Lin

Kuan-Kai Juan

Hao-Hui Yin

Yung-chi Shen

Hung-Yen Chen

King Yin Wang

Chih-Chuan Chen

Chih-Lung Tai

Chang-Long Wu

Yuh Chen

Chin-Yuan Hu

Der-Ray Huaug

Yao-Yu Lee

A controller chip for controlling a motor device includes a first input port, a first output port, a controller, and a signal processing circuit. The first input port is arranged to receive a motor control input. The first output port is arranged to generate a motor control output. The controller is arranged to generate an output signal according to an input signal, and has a second input port for receiving the input signal and a second output port for outputting the output signal. The input signal is derived from the motor control input, and the motor control output is derived from the output signal. The signal processing circuit has a target interconnection configuration selected from a plurality of candidate interconnection configurations each including an interconnection between the first input port and the second input port and an interconnection between the first output port and the second output port.

Controller chip with signal swapping capability for controlling motor device and related method thereof

The present invention discloses read and write power control methods and system for an optical recording device that records information on an optical disk having read-only areas. The read and write power control methods respectively introduce the steps of determining a specific level of a former power control signal output based on a former power control, and then according to the specific level, setting a predetermined level of a power control signal to induce a present power control for rapidly outputting a proper power of the pick-up head. Accordingly, the level transition of the read/write power control signal can be shortened and even eliminated. An unstable read/write power output for the pick-up head can be avoided.

Read and write power control methods and system for optical recording device

An automatic power control system, an automatic power control method, a down sampling circuit and a down sampling method. The automatic power control system is incorporated in an optical disc drive comprising a laser diode for receiving a control signal to generate a laser beam; and a photodetector for detecting the laser beam to generate an analog input signal. The automatic power control system comprises an analog-to-digital converter, a down sampling circuit, a comparator, and a digital-to-analog converter. The analog-to-digital converter converts the analog input signal to digital data. The down sampling circuit, coupled to the analog-to-digital converter, comprises a down sampler, a counter, and a controller. The down sampler receives a predetermined amount of digital data to generate representation data. The counter, coupled to the down sampler, calculates the amount of digital data, and resets the down sampler when the amount equals or exceeds the predetermined count. The controller, coupled to the counter, disables the counter when the digital data is invalid. The comparator, coupled to the down sampling circuit, compares the representation data with predetermined target data to generate error data. The digital-to-analog converter, coupled to the comparator, converts the error data to analog to generate the control signal.

Automatic power control system for optical disc drive and method thereof

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 when the optical disk drive encounters an operating state transition. In a first 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 a second 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.

Apparatus for controlling servo signal gains of an optical disc drive and method of the same

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.

Apparatus for controling servo signal gains of an optical disc drive and method of same

An automatic power control system, a down sampling circuit and a down sampling method. The automatic power control system is incorporated in an optical disc drive comprising a laser diode for receiving a control signal to generate a laser beam; and a photodetector for detecting the laser beam to generate an analog input signal. The automatic power control system comprises an analog-to-digital converter, a down sampling circuit, a comparator, and a digital-to-analog converter. The analog-to-digital converter converts the analog input signal to digital data. The down sampling circuit, coupled to the analog-to-digital converter, comprises a down sampler, a counter, and a controller. The down sampler receives a predetermined amount of digital data to generate representation data. The counter, coupled to the down sampler, calculates the amount of digital data, and resets the down sampler when the amount equals or exceeds the predetermined count. The controller, coupled to the counter, disables the counter when the digital data is invalid. The comparator, coupled to the down sampling circuit, compares the representation data with predetermined target data to generate error data. The digital-to-analog converter, coupled to the comparator, converts the error data to analog to generate the control signal.

A system for determining groove/land (G/L) switching points of an optical disc is disclosed. The system includes a motor rotating signal generating apparatus, an detection apparatus, and a G/L switching point generating apparatus. The motor rotating signal generating apparatus is for sensing the rotation of a motor to generate a motor rotating signal with a period corresponding to the rotation of the optical disc. Also, the detection apparatus is used for receiving the motor rotating signal and an original G/L switching point signal and utilizing the motor rotating signal and the original G/L switching point signal to determine a location of an reproduced G/L switching point of the optical disc. The G/L switching point generating apparatus is for generating an reproduced G/L switching point signal according to the location of the reproduced G/L switching point determined by the detection apparatus.

System and method for determining groove/land switching points of an optical disc utilizing a motor rotating signal and original switching points

An apparatus for light spot servo signal detection for reading an optical recording medium having a plurality of non-writable areas between writable data areas containing address information. An optical pickup provides a light spot to the non-writable areas of the optical recording medium with a predetermined state according to a control signal, and detects optical reflecting signals from the optical recording medium to generate a detection signal. A signal adjusting module offsets signal levels of the detection signal to an operating range to generate an offset shifted detection signal. An analog to digital converter digitizes the offset shifted detection signal to generate a digital signal. A detection circuit detects the servo detection signal according to the digital signal.

Apparatus and methods for light spot servo signal detection

A method for controlling the recording speed of a multi-layered optical disc divides a multi-layered optical disc into a plurality of zones with each zone having a corresponding recording speed. It is then determined which zones need the recording speed to be reduced according to the quality of the optical disc. When the optical drive records data onto an inferior quality zone, it reduces the recording speed to guarantee the reliability of recorded data and enhance recording quality. When the optical drive records data on the next recording layer and has passed the zone that corresponds to the inferior quality zone of the previous recording layer, it increases the recording speed. Thereby the method ensures both quality and efficiency. Furthermore, the recording speed of each subsequent zone of the next recording layer corresponds to the recording speed of each previous zone of the recording layer.

Method for controlling the record speed of a multi-layered optical disc

An apparatus for obtaining a push-pull signal is disclosed. The apparatus includes: a first amplifier coupled to a first fluctuating signal for utilizing a first gain value to amplify the first fluctuating signal and then outputting a first amplified fluctuating signal; a second amplifier coupled to a second fluctuating signal for utilizing a second gain value to amplify the second fluctuating signal and then outputting a second amplified fluctuating signal; a subtractor electrically connected to the first and second amplifiers for subtracting the second amplified fluctuating signal from the first amplified fluctuating signal to generate the push-pull signal; and a level decision unit electrically connected to the first and second amplifiers for controlling the amplitudes of signals amplified by the first and second amplifiers when the optical disc drive is switched from a first operating mode to a second operating mode.

Method and apparatus applied in optical disc drive for obtaining push-pull signal via adjusting amplifying gain according to fluctuating signals generated from photo detector of pick-up head

A laser power control system and related method for reducing a settling time in a target laser power transition are disclosed. The laser power control system includes a state decision circuit, for generating a state decision signal according to a selected operational state of a target circuit; a plurality of buffers, for storing a plurality of control data corresponding to a plurality of candidate operational states of the target circuit respectively; and a multiplexer, coupled between the state decision circuit and the buffers, for coupling a selected buffer of the buffers and the target circuit according to the state decision signal for outputting a control datum stored in the selected buffer to the target circuit.

Laser power control system and method

A signal processing apparatus includes sample and hold units for holding a plurality of analog photo diode signals. A signal holding controller generates control signals to the sample and hold units for holding the analog photo diode signals. Analog adjusting modules adjust the held analog photo diode signals. A multiplexer selectively couples one input end of the multiplexer to the output end of the multiplexer for outputting the adjusted analog photo diode signals. An analog to digital converter converts the adjusted analog photo diode signals into digital photo diode signals.

Signal processing apparatus and method for an optical disc drive

A method for controlling a specific output power level emitted from a laser diode (LD) in an optical pick-up head unit (OPU) is disclosed. The LD is configured to provide a plurality of output power levels for accessing/recording an optical disc. The method includes: determining a specific power control value according to a first output power level, a second output power level, a first power control value of the first output power level, and the specific output power level, wherein the first output power level is less than the specific output power level and greater than the second output power level; and driving the LD to emit the specific output power level according to the specific power control value, the first power control value, and a second power control value of the second output power level.

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Taipei, Taiwan

Ming-Jiou Yu