Patent ID: 7379405

Claim:
A method for promptly protecting a voice coil motor in an optical disk drive from over current, comprising the following steps: (A) allowing a data signal processor (DSP) to execute a protect module for the voice coil motor every preset time interval; (B) the DSP executing the following further steps during execution of the protect module: (b1) reading tracking error (TE)/focusing error (FE) and determining if TE/FE is over a safety range; (b2) starting a gain decrease operation of a signal amplifier if TE/FE has been over the safety range for more than a first preset number of times so as to lower a control current outputting to the voice coil motor; and (b3) starting an operation of speed reduction and a low current operation of a controller to ensure that the voice coil motor is safe if TE/FE has been over the safety range for more than a second preset number of times.