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DESCRIPTION OF CIRCUIT
1. ALPC (AUTOMATIC LASER POWER CONTROL) CIRCUIT
1-1. BLOCK DIAGRAM
1-2. ALPC (AUTOMATIC LASER POWER CONTROL) CIRCUIT OPERATION
THE ALPC BLOCK DETECTS THE LASER OUTPUT POWER OF THE FRONT MONITOR. THE POWER SIG-
NAL DETECTED WITH THE PD FOR FRONT MONITOR
DETECTION IS INPUT THE VOLTAGE FROM THE VPD PIN(123PIN) OR THE FPDM PIN(127PIN), THE REF-
ERENCE SIGNAL OF THE INPUT SIGNAL IS
INPUT FROM THE VREFPD PIN(124PIN). THE ALPC BLOCK GENERATES THE SINGALS FROM THE INPUT
LASER POWER SIGNALS IN THE
FOLLOWING DETECTION SYSTEMS. THIS BLOCK HAS FOUR DETECTION PATHS:ALL AVERAGE VALUE
PATH, MULTI PULSE AVERAGE/PEAK VALUE
DETECTION PATH, ERASE/BOTTOM VALUE DETECTION PATH, SPACE/PLAYBACK POWER VALUE
DETECTION PATH.