Table of Contents
Advertisement
1. ALPC (Automatic Laser Power Control) Circuit
1-1. Block Diagram
CN 101
VREFPD
Optical
Pick-up
HOP-7531TS
FM
LD
PD
LDD
1-2. ALPC (Automatic Laser Power Control) Circuit Operation
The ALPC block detects the laser output power of the front monitor. The power signal detected with the PD for front monitor
detection is input the voltage from the VPD pin(126Pin) or the FPDM pin(127Pin), the reference signal of the input signal is
input from the VREFPD pin(128Pin). 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.
40
DESCRIPTION OF CIRCUIT
IC 121
AN22112A
128
APC
127 FPDM
19
126
VPD
D/A
D/A
D/A
D/A
D/A
D/A
LPF
VGA
VGA
49
50
SH3
SH2
Serial
I/F
Ave
S/H2
M
Erase
P
S/H3
X
Space
S/H1
51
SH1
IC 201
MN103S86G
A/D
Write
Strategy
S/H
Signal
ADSC
Hide quick links:
Advertisement
Table of Contents
