Mediatek Corporation

Mediatek Incorporation

Ching-Chuan Hsu

Hsueh-Kun Liao

Yung-Chih Li

A laser power control unit used for controlling the laser power of an optical pick-up unit (OPU) is provided. The laser power control unit includes: at least one analog-to-digital converter (ADC) electrically coupled to the OPU for transferring a front photodiode output signal into a digital feedback signal; and at least one digital control circuit electrically coupled to the ADC for generating a power control signal and outputting the power control signal to the OPU in order to control the laser power of the OPU. The digital control circuit has a compensation circuit used for generating a compensation value according to a difference between the digital feedback signal and a digital target feedback signal so as to adjust the power control signal. The front photodiode output signal corresponds to the laser power of the OPU.

Laser power control unit and method for performing auto power control

A laser power controller for performing an auto power control to control the laser power of an optical pick-up unit (OPU) includes: a sample/hold circuit used for sampling and holding a front photodiode output signal to generate an analog feedback signal; an analog-to-digital converter (ADC) electrically coupled to the sample/hold circuit for transferring the analog feedback signal into a digital feedback signal; and a digital control circuit electrically coupled to the ADC for generating a power control signal and outputting the power control signal to the OPU in order to control the laser power of the OPU. The front photodiode output signal corresponds to the laser power of the OPU.

Growing community of inventors

Hsin-Chu Hsien, Taiwan

Ching-Chuan Hsu