Patent ID: 7768889

Claim:
A laser power control circuit comprising: a system control module for respectively generating a first write channel target value, a second write channel target value, a first overdrive channel target value and a second overdrive channel target value in a calibration mode a driving module coupled to the system control module for driving a laser generator, the driving module comprising: a write channel control module for generating a first write channel signal and a second write channel signal according to the first and second write channel target values, respectively; a laser generator driving unit coupled to the write channel control module for driving the laser generator according to the first and second write channel signals; and an overdrive channel control module coupled to the laser generator driving unit and the system control module for generating a first overdrive channel signal and a second overdrive channel signal according to the first and second overdrive channel target values, respectively; and a detection module for detecting a first laser power value and a second laser power value of the laser generator, the first and second laser power values respectively corresponding to the first and second write channel signals; wherein the system control module comprises a logic control unit coupled to the laser generator driving unit for driving the laser generator driving unit according to a second duty cycle to drive the laser generator according to the first and second overdrive channel signals, the system control module determines a first mapping relationship between a write channel target value and a laser power value according to the first and second write channel target values and the first and second laser power values, and the system control module determines a predetermined write channel target value corresponding to a predetermined laser power value according to the first mapping relationship in a run mode.