Patent ID: 7626905

Claim:
A device for protecting a slicer in reading signals on a defect optical disc from disturbance and instability, said device comprising: a defect detection unit, receiving a plurality of defect detection signals for setting a plurality of defect flag signals, wherein said plurality of defect detection signals at least include an envelope signal of a RF signal and bit modulation signals; said slicer, receiving and digitalizing said RF signal comprising: a high pass filter, filtering said RF signal to generate a high-pass-filtered RF signal; a comparator electrically connected to said high pass filter, comparing said high-pass-filtered RF signal from said high pass filter with a referred DC level to generate a digitalized RF signal; a charge-pump unit electrically connected to said comparator, comprising a plurality of current sources to compensate said digitalized RF signal from said comparator; and a low pass filter electrically connected to said charge-pump unit and said comparator, filtering said digitalized RF signal from said charge-pump unit and generates a slice level to feedback to said comparator as said referred DC level; and a logic combination unit, performing logic operation on said defect flag signals in order to detect a specified defect and to trigger defect protection for said slicer.